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  • 1.
    Alanne, Kari
    et al.
    Department of Energy Technology, Aalto University.
    Kari, Saari
    Department of Energy Technology, Aalto University.
    Mannu, Kuosa
    Department of Energy Technology, Aalto University.
    Md., Rahman
    Department of Energy Technology, Aalto University.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Microgeneration and Desalination Using Rotary Steam Engine (RTE) Technology2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper discusses the conditions to develop a micro-cogeneration plant based on biomass-fuelled rotary steam engine (RSE). The use of RSE in micro-cogeneration is justifiable due to relatively high electrical efficiency, capability of applying versatile thermal sources and low operational temperatures and pressures. At steam temperatures 200…300ºC, the electrical efficiency of 20 % may be obtained with the electrical power varying between 1…20 kWe. The other advantages of an RSE are that it is lubricant free and the noise level is low. In residential applications, an RSE may be considered an alternative for Stirling Engines and internal combustion engines, when integrated into a hydronic heating system and electrical grid. Another promising adaptation is desalination. A solar-powered RSE micro-cogeneration system would provide an inexpensive option to supply fresh water and electricity for the rural areas in developing countries that have access to sea water. A 10 kWe RSE plant combined with a once-through multi-stage flash (MSF) distillation plant is estimated to have potential of producing pure water from 180 to 800 kg/h.

  • 2.
    Alanne, Kari
    et al.
    Department of Energy Technology, Aalto University.
    Saari, Kari
    Department of Energy Technology, Aalto University.
    Jokisalo, Juha
    Department of Energy Technology, Aalto University.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Thermo-economic analysis of a micro-cogeneration system based on a rotary steam engine (RSE)2012Ingår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 44, s. 11-20Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A rotary steam engine (RSE) is a simple, small, quiet and lubricant-free option for micro-cogeneration. It is capable of exploiting versatile thermal sources and steam temperatures of 150 to 180 ºC, which allow operational pressures less than 10 bar for electrical power ranges of 1 to 20 kWe. An RSE can be easily integrated in commercially available biomass-fired household boilers. In this paper, we characterize the boiler-integrated RSE micro-cogeneration system and specify a two-control-volume thermodynamic model to conduct performance analyses in residential applications. Our computational analysis suggests that an RSE integrated with a 17 kWth pellet-fuelled boiler can obtain an electrical output of 1.925 kWe, in the design temperature of 150 ºC, the electrical efficiency being 9% (LHV) and the thermal efficiency 77% (LHV). In a single-family house inFinland, the above system would operate up to 1274 h/a, meeting 31% of the house’s electrical demand. The amount of electricity delivered into the grid is 989 kWh/a. An economic analysis suggests that incremental costs not exceeding € 1,500 are justifiable at payback periods less than five years, when compared to standard boilers.

  • 3. Asim, Muhammad
    et al.
    Imran, Muhammad
    Leung, Michael K. H.
    Kumar, N. T. Uday
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Kashif, Faiza
    Experimental analysis of solar thermal integrated MD system for cogeneration of drinking water and hot water for single family villa in Dubai using flat plate and evacuated tube solar collectors2017Ingår i: Desalination and Water Treatment, ISSN 1944-3994, E-ISSN 1944-3986, Vol. 92, s. 46-59Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents the experimental analysis performed on solar thermal integrated membrane distillation (MD) system using flat plate and evacuated tube collectors. The system will be utilized for cogeneration of drinking water and domestic hot water for single family in Dubai comprising of four to five members. Experiments have been performed in Ras Al Khaimah Research and Innovation Centre (RAKRIC) facility. The experimental setup has been installed to achieve the required production of 15-25 L/d of drinking water and 250 L/d of hot water for domestic purposes. Experiments have been performed on MD setup at optimized flow rates of 6 L/min on hot side and 3 L/min on cold side for producing the desired distillate. The hot side and cold side MD temperature has been maintained between 60 degrees C and 70 degrees C, and 20 degrees C and 30 degrees C. The total annual energy demand comes out to be 8,223 kWh (6,000 kWh is for pure water and 2,223 kWh for hot water). The optimum aperture areas for flat plate and evacuated tube collector field have been identified as 8.5 and 7.5 m(2), respectively. Annual energy consumption per liter for pure water production is 1, 0.85 and 0.7 kWh/L for different MD hot and cold inlet temperatures.

  • 4. Asim, Muhammad
    et al.
    Kumar, N. T. Uday
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Feasibility analysis of solar combi-system for simultaneous production of pure drinking water via membrane distillation and domestic hot water for single-family villa: pilot plant setup in Dubai2016Ingår i: Desalination and Water Treatment, ISSN 1944-3994, E-ISSN 1944-3986, Vol. 57, nr 46, s. 21674-21684Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents the feasibility study of installation of a solar-driven integrated MD desalination system for simultaneous production of pure drinking water and solar domestic hot water in United Arab Emirates (UAE) for a single-family villa comprising of 4-5 persons. In order to satisfy the current and future demand of water for domestic purposes, the desalination of seawater is considered to be one of the most effective and strategic technique in UAE. The stress on the underground water aquifers, rapid industrial growth, and increase in urban population in UAE results in the tremendous increase in fresh water demand during the past few decades. Since the local municipalities also provide the desalinated fresh water to the people but they mostly rely on bottled water for drinking purpose. In this paper, the pilot setup plant is designed, commissioned, and installed on site in UAE using air gap membrane distillation desalination process to fulfill the demand of 15-25 L/d of pure drinking water and 250 L/d of domestic hot water for a single-family villa. Experimental analyses have been performed on this setup during summer on flat plate solar collectors having different aperture areas (Experiments have been performed for aperture area of 11.9 m(2) in this research study for feasibility purpose). The average hot-side temperature ranges from 50 to 70 degrees C and average cold-side temperature of 35 degrees C.

  • 5.
    Birru, Eyerusalem
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Erlich, Catharina
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Beyene, Getachew
    Addis Ababa University, Ethiopia.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Assessing the potential of energy saving in a traditional sugar canemill during steady state and transient conditions: part I: basecase plant model2015Ingår i: Biomass Conversion and Biorefinery, ISSN 2190-6823Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sugar cane mills are energy intensive industries andalso have a large potential of providing surplus energy interms of heat or power. Identification of heat and mechanicallosses in sugar mills is one approach in indicating energysaving potential in sugar mills, especially in traditional mills.Such assessment of the energy flows in sugar mills needs to bedone both in steady state and transient conditions (where suddenstoppages occur). In this paper, such an approach is consideredwhere a base case plant is modeled for steady state andtransient state operations. For the transient state study, a typicalstoppage is chosen and three different scenarios aremodeled. Heat loss calculations are done for major cogenerationunits and for the amount accumulated of the surplus bagassewhen the steady state operation is estimated. The resultsof the models show that during steady state operation, thelosses related to mechanical prime movers is on the higherside as the mills and shredder are driven by steamand generatemechanical power higher than what is needed by the mills andthe shredder equipment themselves. In the transient statescenarios, where fuel oil is introduced during press mill stoppage,there is steam wasted (steam that could have been usedfor mechanical power generation) starting from the periodwhere the fuel oil is introduced until the power required duringthe stoppage is reached. The CO2 emission during the use offuel oil is also quite significant during the stoppage.

  • 6.
    Birru, Eyerusalem
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Erlich, Catharina
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Beyene, Getachew
    Addis Ababa University, Ethiopia.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Upgrading of a traditional sugar cane mill to a modern milland assessing the potential of energy saving during steady stateand transient conditions: part II: models for a modifiedcogeneration unit2016Ingår i: Biomass Conversion and Biorefinery, ISSN 2190-6823, Vol. 6, nr 2, s. 233-245Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It is known that there is a significant amount ofthermal energy used for the sugar cane industry for the purposeof power production and for use in the sugar or ethanolprocessing in cane sugar industries. Likewise, it is understoodthat there are substantial amounts of waste heat that is notbeing recovered, in particular for traditional sugar mills. Regardlessof this, energy conservation is given less considerationas compared to operational convenience due to the factthat sugar mills are self-sufficient in energy (heat and power).The identification of such potential heat loss areas (especiallyduring transient conditions) suggests the sugar mills play avital role in energy saving. In this study, a modified setup ofthe base case plant considered in part I of this paper is assessedfor its energy potential and possible major heat losses duringsteady state and transient conditions where 2-h stoppage of themill presses are considered to occur. For the modified setup,there are two major scenarios considered having two subscenarioseach. The result of the assessment showed that thesteady state assumption scenario of the modified plant (wherebagasse drying is not considered) indicated a 20 % reductionin the losses considered which resulted in a 57 % power generationincrease as compared to the steady state model of thebase case plant. It is also possible to save excess bagasse bydrying the bagasse for later use during unexpected stoppage.The carbon dioxide emission (amounting 29 t/day in case 2aof this study) that occurs during the use of fuel oil during suchstoppages will thus be avoided. The simple economic analysisshowed that it is only in case 2a where fuel oil cost is includedin the operation cost that resulted in a negative NPV. Since therest of the scenarios use bagasse as a fuel which is free, theNPV for all was positive. For the electricity price of 0.04 US$/kWh and discount rate of 15 %, the minimum paybackperiod attained is about 3 years (case 1b) where the bagassemoisture content is 30 % whereas the maximum payback periodis 6 years (case 1a) where there is no bagasse dryingconsidered.

  • 7.
    Birru, Eyerusalem
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Erlich, Catharina
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Herrera, Idalberto
    University “Marta Abreu” of Las Villas (UCLV), Cuba.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Feychting, Sofia
    KTH, Skolan för industriell teknik och management (ITM).
    Vitez, Marina
    KTH, Skolan för industriell teknik och management (ITM).
    Abdulhadi, Emma Bednarcik
    KTH, Skolan för industriell teknik och management (ITM).
    Larsson, Anna
    KTH, Skolan för industriell teknik och management (ITM).
    Onoszko, Emanuel
    KTH, Skolan för industriell teknik och management (ITM).
    Hallersbo, Mattias
    KTH, Skolan för industriell teknik och management (ITM).
    Weilenmann, Louise
    KTH, Skolan för industriell teknik och management (ITM).
    Puskoriute, Laura
    KTH, Skolan för industriell teknik och management (ITM).
    A Comparison of Various Technological Options for Improving Energy and Water Use Efficiency in a Traditional Sugar Mill2016Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 8, nr 12, artikel-id 1227Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study is a comparison of four technological improvements proposed in previous works for the Cuban sugar mill Carlos Balino. These technological options are: (1) utilization of excess wastewater for enhanced imbibition; (2) utilization of waste heat for thermally driven cooling; (3) utilization of excess bagasse for pellets; and (4) modification of the cogeneration unit for maximum electric power generation. The method used for the evaluation of the technological options involves using criteria such as energy saving, financial gains, and CO2 emission saving potential. The results of the analysis show that the first three technological improvement options are attractive only during the crushing season. On the other hand, the last technological improvement option can be attractive if a year round generation of surplus power is sought. The first technological improvement option leads to only minor changes in energy utilization, but the increase in sugar yield of 8.7% leads to attractive profitability with an extremely low payback period. The CO2 emissions saved due to the fourth technological improvement option are the highest (22,000 tonnes/year) and the cost of CO2 emissions saved for the third technological improvement option (lowest) amount to 41 USD/tonne of CO2 emissions saved. The cycle efficiencies of the third and fourth technological improvement options are 37.9% and 36.8%, respectively, with payback periods of 2.3 and 1.6 years. The second technological improvement option is the least attractive alternative of the group.

  • 8.
    Chuanfeng, Liu
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Membrane Distillation and Applications for Water Purification in Thermal Cogeneration: A Pre-study2005Rapport (Refereegranskat)
  • 9.
    Fortkamp, Uwe
    et al.
    IVL Svenska Miljöinstitutet/IVL Swedish Environmental Research.
    Royen, Hugo
    IVL Svenska Miljöinstitutet/IVL Swedish Environmental Research.
    Klingspor, Magnus
    IVL Svenska Miljöinstitutet/IVL Swedish Environmental Research.
    Ekengren, Östen
    IVL Svenska Miljöinstitutet/IVL Swedish Environmental Research.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Woldemariam, Daniel
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Membrane Distillation pilot tests for different wastewaters: Separation of pharmaceutical residues and treatment of flue gas condensate with Xzero Membrane Distillation in Pilot Scale at Hammarby Sjöstadsverk2015Rapport (Refereegranskat)
    Abstract [en]

    The purpose of the project was to evaluate membrane distillation as an alternative separation technology for different water purification applications. Membrane distillation (MD) is a unit operation that uses water repellent (hydrophobic) membranes as a barrier for contaminated water. The driving force for the process is the vapor pressure over the membrane achieved by applying temperature differences between a warm and a cold side. The process takes place at temperatures below 100 °C and at ambient pressure. Pilot studies were performed at Hammarby Sjöstadsverk to test the separation of pharmaceutical residues from municipal wastewater after biological treatment as well as final treatment of flue gas condensate. In both cases, most target compounds were separated to a very high degree, often more than 90 %. The project also included energy studies that showed some potential for energy optimisation of the current equipment and provided input for energy efficient set-up, e.g. by using waste heat such as the return flow from district heating. Varying results for the single modules also indicated optimisation potential. The project was performed in cooperation between IVL Swedish Environmental Research Institute, Xzero AB as technology provider, and KTH (Royal institute of technology) for energy studies

  • 10. Hantsch, A.
    et al.
    Gross, U.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Heat Transfer Augmentation: Radiative-Convective Heat Transfer in a Tube With Fiber Array Inserts2010Ingår i: Journal of heat transfer, ISSN 0022-1481, E-ISSN 1528-8943, Vol. 132, nr 2Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Gas-phase heat transfer plays a critical role in many high temperature applications, such as preheaters, combustors, and other thermal equipment. In such cases common heat transfer augmentation methods rely on the convective component alone to achieve improved internal performance. Radiatively assisted heat transfer augmentation has been suggested as a way to overcome limitations in convective-only enhancement. One example of such a technique is the fiber array insert; thermal radiation emitted by tube walls is captured by a large number of slender fibers, which in turn convect heat to the flowing fluid. Previous numerical studies have indicated that this technique represents a promising enhancement method warranting further investigation. This paper presents results from an experimentally based feasibility study of fiber array inserts for heat transfer augmentation in an externally heated duct. Fibers composed of 140 mu m silicon carbide and 150 mu m stainless steel were assembled in arrays with porosities around 0.98, and were tested for empty-tube Reynolds numbers ranging from 17,500 to 112,500 and wall temperatures from ambient up to 750 degrees C. The arrays cause a significant pressure drop-roughly two orders of magnitude higher than the empty-tube case-but tube-side heat transfer coefficients were improved by up to 100% over the convective-only case in the low flow rate regime. The stainless steel fiber array exhibited similar heat transfer performance as the silicon carbide case, although pressure drop characteristics differed owing to variations in fluid-structure flow phenomena. Pressure drop data were roughly within the range of d'Arcy law predictions for both arrays, and deviations could be explained by inhomogeneities in fiber-to-fiber spacing. Heat transfer was found to depend nonlinearly on wall temperature and flow rate, in contrast to previously reported numerical data.

  • 11.
    Kabalina, Natalia
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. Universidade de Lisboa, Portugal.
    Costa, Mario
    Weihong, Yang
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Energy and economic assessment of a polygeneration district heating and cooling system based on gasification of refuse derived fuels2017Ingår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 137, s. 696-705Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Conventional district heating and cooling (DHC) systems are compelled to reduce their fossil fuel dependency while ensuring profitability as cooling and heating demands decline. One solution is to retrofit the system with a gasifier and product gas upgrading equipment so that the system will be able to diversify its fuel input, including biomass and waste resources, while simultaneously producing synthetic natural gas (SNG), synthetic gas (syngas) and char complementarily to heat, cold and electricity. The main objective of this study is to assess energetically and economically a polygeneration DHC system based on gasification of refuse derived fuels considering the following sub-product scenarios: char; char and syngas; char and SNG; and char, syngas and SNG. The results show that when char is the only sub product of the modified DHC system, the investment payback is 3 years, the discounted net cash flow (DNCF) is 142 mln USD, and the system trigeneration efficiency is 83.6%. When other sub-products are supplied by the system, its performance reduces but the system DNCF increases, while the investment payback remains constant.

  • 12.
    Kabalina, Natalia
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi. Instituto Superior Tecnico, Universidade de Lisboa, Lisboa, Portugal.
    Costa, Mario
    Instituto Superior Tecnico, Universidade de Lisboa, Lisboa, Portugal.
    Weihong, Yang
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Energi- och ugnsteknik.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Impact of a reduction in heating, cooling and electricity loads on the performance of a polygeneration district heating and cooling system based on waste gasification2018Ingår i: Energy Journal, ISSN 0195-6574, E-ISSN 1944-9089, Vol. 151, s. 594-604Artikel i tidskrift (Refereegranskat)
  • 13.
    Kabalina, Natalia
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. Univ Lisbon, Portugal.
    Costa, Mario
    Weihong, Yang
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Production of Synthetic Natural Gas from Refuse-Derived Fuel Gasification for Use in a Polygeneration District Heating and Cooling System2016Ingår i: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, nr 12, artikel-id 1080Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nowadays conventional district heating and cooling (DHC) systems face the challenge of reducing fossil fuel dependency while maintaining profitability. To address these issues, this study examines the possibility of retrofitting DHC systems with refuse-derived fuel (RDF) gasifiers and gas upgrading equipment. A novel system is proposed based on the modification of an existing DHC system. Thermodynamic and economic models were established to allow for a parametric analysis of key parameters. The study revealed that such an upgrade is both feasible and economically viable. In the basic scenario, the retrofitted DHC system can simultaneously produce 60.3 GWh/year of heat, 65.1 GWh/year of cold, 33.2 GWh/year of electricity and 789.5 tons/year of synthetic natural gas. A significant part of the heat load can be generated from the waste heat of the upgrading equipment. The investment in retrofitting the polygeneration DHC system presents a payback period of 3 years.

  • 14.
    Kabalina, Natalia
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. Universidade de Lisboa, Portugal.
    Costa, Mario
    Weihong, Yang
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Santarelli, Massimo
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. DENERG Politecnico di Torino, Italy.
    Exergy analysis of a polygeneration-enabled district heating and cooling system based on gasification of refuse derived fuel2017Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 141, s. 760-773Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    District heating and cooling (DHC) systems, modified or retrofitted with integration of gasifiers and gas upgrading equipment, represent promising alternatives to traditional approaches since various scenarios of products complementary to heat, cold, and electricity can be realized, namely: char only; char and syngas; char, synthetic natural gas (SNG) and hydrogen (H-2); and char, syngas, SNG and H-2. This manuscript evaluates a polygeneration-enabled DHC system in detail (operation during a typical year) from exergetic and exergoeconomic perspectives. The base DHC system utilizes natural gas as fuel with a nominal capacity of 29 MW heat, 35 MW of cold, and 5 MW of electricity. The retrofit employs refuse derived fuel (RDF) as feedstock to an atmospheric gasifier with downstream gas clean-up, a gas turbine, and a heat recovery steam generator along with heat exchangers for integration with the base DHC system. The exergy analysis revealed that the polygeneration system presents adequate performance at all scenarios established. Among the sets of value-added products the combination of char and syngas is the most beneficial as the system efficiency reaches a value of similar to 72%. The outcomes of the exergoeconomic analysis support the exergy results. The lower production costs for value-added products are achieved for the maximum simultaneous char and syngas production, with each of these costs estimated to be 6.1 USD/GJ.

  • 15.
    Khan, E. U.
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Bundschuh, J.
    Biogas energy polygeneration integrated with air-gap membrane distillation (AGMD) as arsenic mitigation option in rural Bangladesh2016Ingår i: Arsenic Research and Global Sustainability - Proceedings of the 6th International Congress on Arsenic in the Environment, AS 2016, CRC Press/Balkema , 2016, s. 554-556Konferensbidrag (Refereegranskat)
    Abstract [en]

    Sustainable energy and drinking water access have been seen as major challenges for rural households in Bangladesh despite of governmental and non-governmental organizations have been made extensive efforts. This study contemplates a universal approach towards tackling both of these issues via biogas based polygeneration integrated with membrane distillation employed at the village level. The specific technologies chosen for the key energy conversion steps are as follows: plug-flow digester (co-digestion and mesophilic condition); internal combustion engine; and air-gap membrane distillation. The proposed techno-economic results show that daily electricity demand can be met with such a system while simultaneously providing 0.4 m3cooking fuel and 2–3 L pure drinking water. Cost analysis illustrates that the approach is highly favorable compare to other available system. The payback time of such system is between 2 and 2.5 years.

  • 16.
    Khan, Ershad Ullah
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Mainali, Brijesh
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Energi och klimatstudier, ECS.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Silveira, Semida
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Energi och klimatstudier, ECS.
    Techno-economic analysis of small scale biogas based polygeneration systems: Bangladesh case study2014Ingår i: Sustainable Energy Technologies and Assessments, ISSN 2213-1388, E-ISSN 2213-1396, Vol. 7, s. 68-78Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Access to electricity, clean energy, and safe drinking water services are genuine needs of the rural poor for their welfare. These needs can be addressed either individually or in an integrated approach. Biogas digesters are promising in the rural setting and integration of biogas production with power generation and water purification is an innovative concept that could be applied in remote areas of Bangladesh. This paper presents a new concept for integrated biogas based polygeneration and analyzes the techno-economic performance of the scheme for meeting the demand of electricity, cooking energy and safe drinking water of 30 households in a rural village of Bangladesh. The specific technologies chosen for the key energy conversion steps are as follows: plug-flow digester; internal combustion engine; and air-gap membrane distillation. Mass flows and energy balance, levelized cost of producing electricity, cooking gas and safe drinking water as well as the payback period of such a polygeneration system were analyzed. The results indicate that this polygeneration system is much more competitive and promising (in terms of levelized cost) than other available technologies when attempting to solve the energy and arsenic-related problems in Bangladesh. The payback period of such system is between 2.6 and 4 years.

  • 17.
    Khan, MD. Ershad Ullah
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Water purification of arsenic contaminated drinking water via air gap membrane distillation (AGMD)2014Ingår i: Periodica Polytechnica, Mechanical Engineering, ISSN 1587-379X, Vol. 58, nr 1, s. 47-53Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Arsenic contamination in shallow tubewell water is a serioushealth issue in Bangladesh and other Southeast Asian countries.Rural and remote areas in these locations continue toface tremendous challenges in providing access to affordableand safe arsenic-free drinking water. In recent years, intensiveefforts have been undertaken to identify appropriate technologiesfor arsenic removal. This study examines one approach byinvestigating the application of suitable membrane technologies,specifically air gap membrane distillation (AGMD), asa promising method for small-scale, low cost deployment. Theobjective of this study was to test an AGMD commercial prototype(nominal capacity of 2 L/hr) with three different feedstocks:arsenic-containing groundwater (medium concentration) andarsenic-spiked tap water (medium and high concentrations).Results show that the tested AGMD prototype is capable ofachieving excellent separation efficiency, as all product watersamples showed arsenic levels well below WHO accepted limits(10 μg/L) even for initial concentrations over 1800 μg/L.Parametric studies with focus on variation of coolant temperatureillustrate the possibility of integrating AGMD in variousthermal systems.

  • 18.
    Khan, MD. Ershad Ullah
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Hybrid Renewable Energy with Membrane Distillation Polygeneration for Rural Households in Bangladesh: Pani Para Village Case Study2014Ingår i: 2014 INTERNATIONAL CONFERENCE ON RENEWABLE ENERGY RESEARCH AND APPLICATION (ICRERA), IEEE , 2014, s. 359-362Konferensbidrag (Refereegranskat)
    Abstract [en]

    Despite the country's rural electrification program, kerosene is the predominant source for lighting, and woody biomass is virtually the only the option available for cooking. Aside from this energy service challenges the rural population also struggles with unsafe drinking water in terms of widespread arsenic contamination of well water. Access to electricity, clean cooking gas, and safe drinking water services are genuine needs of the rural poor and are essential to improving welfare. These needs can be addressed individually or using an integrated approach. This study considers a holistic approach towards tackling both of these issues via integrated renewable energy-based polygeneration employed at the community level. The polygeneration unit under consideration provides electricity via a pV array and cow dung-fed digester, which in turn is coupled to a gas engine. Excess digester gas is employed for cooking and lighting, while waste heat from the process drives a membrane distillation unit for water purification. The system is sized to serve a community of 52 households (Pani Para, Faridpur District) with 14 kWe peak demand and 250 kWh/day primary electricity loads. Technical assessments and optimization have been conducted with HOMER. Results show that electricity demand can be met with such a system while simultaneously providing 0.4 m(3) cooking fuel and 2-3 L pure drinking water per person per day. Cost estimates indicate that this approach is highly favorable to other renewable options.

  • 19.
    Khan, MD. Ershad Ullah
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Optimization of hybrid renewable energy polygeneration system with membrane distillation for rural households in Bangladesh2015Ingår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 93, s. 1116-1126Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Despite the country's rural electrification program, kerosene is the predominant source for lighting, and woody biomass is virtually the only option available for cooking. The rural population also struggles with unsafe drinking water in terms of widespread arsenic contamination of well water. Biogas plants and pV are individually impractical to serve both cooking, lighting and water purification systems, and their combined applications are extremely limited. This study considers a holistic approach towards tackling both of these issues via integrated renewable energy-based polygeneration employed at the village level. The polygeneration unit under consideration provides electricity via a pV array and animal and agriculture waste-fed digester, which in turn is coupled to a gas engine. Excess digester gas is employed for cooking and lighting, while waste heat from the process drives a membrane distillation unit for water purification. Technical assessments and optimization have been conducted with HOMER (Hybrid Optimization of Multiple Energy Resources). Results show that daily electricity demand can be met with such a system while simultaneously providing 0.4 m3 cooking fuel and 2e3 L pure drinking water. Cost estimates indicate that this approach is highly favorable to other renewable options. The pay back period of such system is between 3 and 4 years.

  • 20.
    Khan, MD. Ershad Ullah
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Review of biogas digester technology in rural Bangladesh2016Ingår i: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 62, s. 247-259Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Bangladesh has been facing severe energy crises (lack of electricity and gas supply network) during the last three decades, especially in rural areas. These areas are characterized by their often inefficient use of woody biomass, mainly for cooking purposes. To avoid the resulting environmental degradation and achieve sustainable development, access to clean and affordable energy is essential. Upgrading existing biomass resources (i.e., animal manure, crop residues, kitchen waste and green wastes) to biogas shows significant promise in this respect. This article presents a review of the current status of biogas digester technology in Bangladesh with focus on households in rural areas, covering 75% of the total population. Currently there exists a substantial gap between technical and cost-effective potential and the achievable potential due to lack of technical knowledge, high installation and operation costs, feedstock availability and limited end user applications. As a result only one percent of the overall biogas potential, estimated at 14.5x106 m3/yr, has been achieved despite government programs for promoting digester installation. Via in-field surveys this review has identified problems in the construction, maintenance and operation of biogas digesters, particularly in overall performance of household digesters. Based on these results a number of operational and technology improvements are suggested. Three digester implementation scenarios are introduced, and performance and cost estimates are projected to 2040. The most ambitious scenario leads to a five-fold increase in biogas output as compared to today’s levels; levelized energy costs can be halved with proper choice of digester technology.

  • 21.
    Kivumbi, Bernard
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi. Department of Biosystems Engineering, Gulu University, Gulu, Uganda.
    Olwa, J.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Menya, E.
    Techno-economic assessment of municipal solid waste gasification for electricity generation: A case study of Kampala City, Uganda2015Ingår i: E-journal CIGR, ISSN 1682-1130, E-ISSN 1682-1130, Vol. 17, nr 4, s. 141-155Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study was aimed at assessing the techno-economic potential of municipal solid waste (MSW) generated in Kampala City for electricity production through gasification. The quantity, characteristics and gasification parameters were determined. In addition, the gasifier- engine system components were sized, and an economic analysis was conducted to obtain the net present value (NPV) and the payback period. This study found that 523 t/d of MSW is collected in Kampala City. The biomass component of MSW was found to be 459.5 t/d with moisture content of 71.09% on as-received basis. The physical characteristics of the gasified biomass included 11.8% moisture content, 88.2% total solids, 25.9% ash content and 57.7 kg/m3 bulk density. The resulting normalized producer gas constituted 11.64% H2, 13.70% CO, 16.09% CO2, 54.12% N2, 4.45% CH4 and lower heating value (LHV) of 4.75 MJ/Nm3. The design fuel flow rate of 0.23 kg/s, specific gasification rate (SGR) of 5089.29 kg h-1 m-2 and specific energy demand of 42.75 GJ m-2 h-1 were obtained. This yields a net electrical power output of 425.17 kW with an overall efficiency of 15.6%. The net annual electricity generation from a single gasifier-engine system was found to be 2.97 GWh/a. The economic analysis for this system worth $887 333 of investment cost yielded a payback period of 6.57 years while the NPV at 6% interest rate was found to be nine years with a value of $316 47.

  • 22.
    Kullab, Alaa
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Fakhrai, Reza
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    CFD Analysis of Spacer-Obstructed Channels in Membrane DistillationManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Spacers are used in desalination and filtration technologies to enhance the hydrodynamic conditions in flow channels, as well as to provide support and separation of membrane sheets. This paper present the main results of computational fluid dynamics (CFD) simulation for flow in spacer-obstructed flow channel for application in membrane distillation (MD). Flow of attack angle, spacer-to-channel thickness and void ratio were the main geometrical parameters that were studied; velocity profiles, shear stress and pressure drops were the main assessment criteria used for evaluation. Results show the flow of attack angle has a very minimum effect on the performance of spacers. The effect of spacer to channel thickness ratio was significant in all assessment parameters. Higher void ratios were found advantageous in promoting flow mixing, but resulted in lower sheer stress and reduced trans-membrane flux. In practice, the selection of the best case would include a trade-off between the cost of membranes needed to produce the required production and pumping.

  • 23.
    Kullab, Alaa
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Fakhrai, Reza
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Experimental evaluation of a modified air-gap membrane distillation prototype2013Ingår i: Desalination and Water Treatment, ISSN 1944-3994, E-ISSN 1944-3986, Vol. 51, nr 25-27, s. 4998-5004Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Modifications were implemented on a semi-commercial air-gap membrane distillation prototype to assess experimentally any improvement in its performance. The main changes were in the air-gap domain with focus on reducing the conductive heat transfer losses by reducing the physical support that separates the membrane from the condensation surface. Moreover, several feed channel spacers were tested as well and assessed based on their effect in increasing the mass transfer and imposed pressure drop. Results show that the modifications increased slightly the distillate mass flow rate by 9-11% and reduced the conductive heat losses by 20-24%. Spacer effect was found to be mainly in imposed pressure drop within the tested types.

  • 24.
    Kullab, Alaa
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Liu, Chuanfeng
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Solar desalination using membrane distillation: Technical evaluation case study2005Ingår i: Proceedings of the Solar World Congress 2005: Bringing Water to the World, Including Proceedings of 34th ASES Annual Conference and Proceedings of 30th National Passive Solar Conference, 2005, s. 2732-2737Konferensbidrag (Refereegranskat)
    Abstract [en]

    Membrane distillation (MD) is a promising desalination technology offering advantages of robustness, scalability, and improved environmental performance as compared to established methods. The aim of this research is to explore the potential of a small scale or stand-alone MD desalination system. The system under consideration consists of an air-gap membrane distillation (AGMD) unit integrated with non-concentrating solar thermal collectors. Scale-up of the MD unit was accomplished via experimental data obtained from an AGMD test facility, and trials were conducted with various feedstock TDS levels, temperatures, and flow rates. Laboratory data obtained from these and other studies demonstrate that MD unit performance is relatively insensitive to variations in feedstock qualities (e.g. pH, TDS levels). Solar data gathered from a case study (Gaza, Palestine) was employed in system simulations. The analysis shows that the system is capable of producing up to 8.5m3/hr of high quality water (< 10 ppm TDS). The power consumption was 150 kWh/m3 (with primary heat recovery), pointing to the need for further studies in ways to utilize low-grade waste heat.

  • 25.
    Kullab, Alaa
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Experimental Evaluation of a Modified Air-gap Membrane Distillation Semi-Commercial PrototypeIngår i: Desalination, ISSN 0011-9164, E-ISSN 1873-4464Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Modifications were implemented on a semi-commercial Air Gap Membrane Distillation prototype to assess experimentally any improvement in its performance. These modifications were many focused on reducing the conductive heat transfer losses by reducing the physical support in the air gap that separate the membrane from the condensation surface. Several feed channel spacers were tested as well and assessed based in their effect in increasing the mass transfer and imposed pressure drop. Results show that the modifications increased slightly the distillate mass flow rate by 9-11 % and reduced the conductive heat losses by 20-24 %. Spacer effect was found to be mainly in imposed pressure drop within the tested types.

  • 26.
    Kullab, Alaa
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Membrane Distillation and Applications for Water Purification in Thermal Cogeneration: Pilot Plant Trials2007Rapport (Refereegranskat)
  • 27.
    Kullab, Alaa
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Membrane distillation and applications for water purification in thermal cogeneration plants2011Ingår i: Separation and Purification Technology, ISSN 1383-5866, E-ISSN 1873-3794, Vol. 76, nr 3, s. 231-237Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Water treatment is an important auxiliary process in all thermal cogeneration plants. In this context membrane distillation (MD) is a novel technology that has potential advantages in: the ability to utilize low-grade heat instead of electricity; reduced sensitivity to fluctuations in pH or salt concentrations. This research is a continuation of a previously conducted theoretical study where the performance of MD-based water treatment was explored via laboratory testing, system simulations of thermodynamic performance, and economic evaluations. The current paper, encompassing field trials, contains details of a test rig deployed at Idbacken Cogeneration Facility (Nykoping, Sweden) with a five-module MD unit capable of producing 1-2 m(3)/day purified water. District heating supply line was employed for heating while municipal water was used for cooling; feed stocks include municipal water and flue gas condensate. A long-term performance evaluation including thorough chemical testing of product water quality is presented. (c) 2010 Elsevier B.V. All rights reserved.

  • 28.
    Kullab, Alaa
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Guillen-Burrieza, Elena
    CIEMAT-Plataforma Solar de Almeria SPAIN.
    Experimental and Simulation of an Air Gap Membrane Distillation SystemIngår i: Desalination, ISSN 0011-9164, E-ISSN 1873-4464Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    This paper covers the details and results of experimental and simulation work carried on an Air Gap Membrane Distillation (AGMD) unit, as a part of EU MEDESOL research project. The aim of the experimental work, carried out during a two-week period, was (a) to evaluate the MD performance with saline water (35 g/l NaCl)  establishing an operation data base, and (b) to conduct a system simulation for the design and evaluation of a three-stage MD desalination system. Experimental results shows that production was 30-40% less in the case of using 35 g/l salinity compared with 1 g/l.  Experimental-based simulations of a three step MD system of two arrangement layout were employed to assess the heat demand. Specific thermal energy consumption was calculated as 950 kWht/m3 for a layout without heat recovery, and 850 kWht/m3 for the layout with one stage heat recovery.

  • 29.
    Kumar, Nutakki Tirumala Uday
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Co-Production Performance Evaluation of a Novel Solar Combi System for Simultaneous Pure Water and Hot Water Supply in Urban Households of UAE2017Ingår i: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 10, nr 4, artikel-id 481Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Water is the most desirable and sparse resource in Gulf cooperation council (GCC) region. Utilization of point-of-use (POU) water treatment devices has been gaining huge market recently due to increase in knowledge of urban population on health related issues over contaminants in decentralized water distribution networks. However, there is no foolproof way of knowing whether the treated water is free of contaminants harmful for drinking and hence reliance on certified bottled water has increased worldwide. The bottling process right from treatment to delivery is highly unsustainable due to huge energy demand along the supply chain. As a step towards sustainability, we investigated various ways of coupling of membrane distillation (MD) process with solar domestic heaters for co-production of domestic heat and pure water. Performance dynamics of various integration techniques have been evaluated and appropriate configuration has been identified for real scale application. A solar combi MD (SCMD) system is experimentally tested for single household application for production 20 L/day of pure water and 250 L/day of hot water simultaneously without any auxiliary heating device. The efficiency of co-production system is compared with individual operation of solar heaters and solar membrane distillation.

  • 30.
    Kumar, Nutakki Tirumala Uday
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Experimental modeling of an air-gap membrane distillation module and simulation of a solar thermal integrated system for water purification2017Ingår i: Desalination and Water Treatment, ISSN 1944-3994, E-ISSN 1944-3986, Vol. 84, s. 123-134Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Membrane distillation is a novel process that could be adapted effectively for many water purification applications. In recent years, several bench, pilot and commercial scale membrane distillation systems with production capacities ranging from 20 L/d to 50 m(3)/d were developed and tested. In this work, a single cassette air-gap membrane distillation (AGMD) module was characterized to identify the effect of process parameters on distillate flux and thermal efficiency. Favorable conditions to obtain distillate flow rate of 1.5-3 kg/h were determined on a bench scale experimental setup. Factorial design of experiments was conducted and response surface methodology (RSM) was applied to develop an empirical regression model relating operating parameters with AGMD system performance indicators. Operating parameters including hot feed inlet temperature (T-Hin), cold feed inlet temperature (T-Cin), feed flow rate (V-f) and feed conductivity (C-f) were considered. Distillate flux (J(d)) and specific performance ratio (SPR) were selected as the performance indicators for the modeling. The developed regression model using RSM was tested by analysis of variance. Regression analysis showed agreement with the experimental data fitted with second-order polynomial model having determination coefficient (R-2) values of 0.996 and 0.941 for J(d) and SPR, respectively. Numerical optimization has been carried out to identify optimal set of operating conditions for achieving desired operation. Also, dynamic simulation of the membrane distillation module integrated solar thermal system has been reported along with validation of the system model by comparing with the experimental data obtained from a pilot scale setup located in UAE.

  • 31. Kumar, Uday N. T.
    et al.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Co-generation of drinking water and domestic hot water using solar thermal integrated membrane distillation system2014Ingår i: Energy Procedia, 2014, s. 2666-2669Konferensbidrag (Refereegranskat)
    Abstract [en]

    Scarcity of fresh water sources, rapid industrial development and increase of urban population in arid regions like UAE lead to tremendous increase in bottled water dependency for drinking purpose. The bottling process right from treatment to delivery is highly unsustainable and hence we focus on the issue of providing pure drinking water in a sustainable way through solar domestic hot water (SDHW) systems. The shift towards sustainability in the oil rich region and recent growth of interest on Membrane Distillation (MD) technique at small scale application development by coupling with solar energy source has motivated us to develop a combined SDHW-MD pilot unit for feasibility analysis. Present application is to co-generate 20 l/day of drinkable water and 250 l/day of domestic hot water for a single family house/villa in UAE region. Experiments are performed for municipal water purification and compared with empirical equation based model developed using laboratory experimental data along with PolySun simulations. Monthly energy consumption and water production profiles have been obtained which would form a basis for detailed dynamic simulation and optimization of system performance.

  • 32. Link, Siim
    et al.
    Arvelakis, Stelios
    Paist, Aadu
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Liliedahl, Truls
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk teknologi.
    Sjöström, Krister
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk teknologi.
    Atmospheric fluidized bed gasification of untreated and leached olive residue, and co-gasification of olive residue, reed, pine pellets and Douglas fir wood chips2012Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 94, s. 89-97Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The fluidized bed gasification of untreated and pre-treated olive residue and pre-treated olive residue mixed with reed, pine pellets and Douglas fir wood chips is studied. Leaching is used as a pre-treatment process targeted on the elimination of alkali metals such as K and Na as well as chlorine to reduce/eliminate the ash-related problems during gasification. The leaching pre-treatment process could affect the producer gas composition toward the lower or higher yield of CO and H-2 of the producer gas depending on the moisture content of parent fuels. The lower total tar yield of the producer gas in the case of leached olive residue was observed compared to untreated olive residue. At the same time, there are present wider varieties of different tar components in the producer gas of the leached olive residue compared to the untreated one. The distinctions in tar composition and content between the leached and untreated olive residue are attributed to the alkali and alkali earth metal and chorine chemistry affected by leaching pre-treatment. The addition of woody fuels and reed at elevated proportions resulted in the lower LHV value compared to the leached olive residue. The tar content of the producer gas is seen to increase adding reed and woody fuels to the leached olive residue, i.e. the producer gas contained additional variety of tar components whereas phenol becomes one of the key components determining the total tar content, apart from benzene, toluene and naphthalene. This is seen to be due to the higher cellulose, hemicelluloses, lignin as well as higher chlorine content of the reed and woody fuels compared to the leached olive residue. The olive residue is seen to be better fuel for gasification compared with woody fuels and reed. Even more, we believe that the leached olive residue is better compared to all other tested fuel/mixtures in this study. It is seen that the proportions of different fuels in the mixture play role in the composition of the producer gas.

  • 33.
    Liu, Chuanfeng
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Applying Membrane Distillation in High-Purity Water Production for Semiconductor Industry2006Ingår i: Ultrapure Water: the definitive journal of high-purity water, ISSN 0747-8291, Vol. AprilArtikel i tidskrift (Refereegranskat)
    Abstract [en]

    While modern ultrapure water (UPW) systems are relatively well developed for semiconductor manufacturing, there is still room for improvement with regards to enhanced reliability, reduced environmental impact, and cost reductions. Membrane distillation (MD) is one promising alternative for high-purity water production that has several advantages compared to reverse osmosis (RO) and other technologies. In short, MD is a thermally driven process utilizing a hydrophobic membrane to produce high-purity water from a contaminated feedstock. Previous studies have shown that MD produces water with equal or superior quality to RO; in addition MD is relatively insensitive to process variations (e.g. pH, TDS levels, etc.), thus opening up the possibility of recycling rinse water. Low-temperature heat sources (i.e. under 100 °C) may be employed, thus allowing MD to be readily integrated into existing processes or even on-site cogeneration.

     

    This paper explores the viability of MD for high-purity water production in a typical semiconductor chip fabrication plant. A brief literature review is included along with water quality analysis reports on typical MD product water. System simulations are employed to highlight possible scenarios with cogeneration. Results show that the specific energy consumption in the case study is around 440 kWh/m3 (thermal) and 0.9 kWh/m3 (electrical).  The specific capital cost is around $1.2-1.5/ m3 for the MD facility. These findings provide a strong impetus towards demonstration trials and other follow-on research and development activities.

  • 34.
    Liu, Chuanfeng
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    The use of membrane distillation in high-purity water production for the semiconductor industry2006Ingår i: Ultrapure Water, ISSN 0747-8291, Vol. 23, nr 3, s. 32-38Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Air gap membrane distillation (AGMD) was investigated as a promising technology for water purification in the semiconductor industry. The AGMD facility considered includes one membrane module, consisting of 10 plastic cassettes stacked together, resulting in 9 feed channels and 9 permeate channels. Polytetrafluoroethylene (PTFE) membranes were employed with a porosity of 80% and a thickness of 0.2 micron (μm). The width of air gap of AGMD is 2 mm. During the experimental period, the pilot plant was operated in three kinds of flow conditions (e.g., 1.36 cubic meters per hour [m/h], 3.04 m3/h, and 2.72 m/h). For simplicity, identical flowrates were maintained for both hot and cold streams. When conducting the experiments, run-time data included pure water production rate, cold- and hot-side temperatures, conductivity of pure water, total dissolved solids (TDS), and pH. Results from laboratory trials were scaled up for use in system simulations featuring MD integrated with distributed heat and power generation from natural gas-fired engines.

  • 35.
    Lorenzi, Guido
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. IN+, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
    da Silva Vieira, Ricardo
    MARETEC/LARSYS, Environment and Energy, Scientific Area, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
    Santos Silva, Carlos Augusto
    IN+, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Techno-economic analysis of utility-scale energy storage in island settingsIngår i: Journal of Energy Storage, E-ISSN 2352-152XArtikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    The decarbonization of the electricity supply in isolated and remote energy systems is an open challenge in the transition to a sustainable energy system. In this paper, the possibility to increase the penetration of renewable energy sources for electricity generationon the island of Terceira (Azores) is investigated through the installation of a utility-scale energy storage facility. The electric power dispatch on the island is simulated through a unit commitment model of the fossil and renewable power plants that has the objective of minimizing the cost of electricity generation. Battery energy storage is employed to partially decouple production and supply, and to provide spinning reserve in case of sudden generator outage. Two technological options, namely lithium-ion and vanadium flow batteries, are compared in terms of net present value and return on investment, with the aim of supporting the decision-making process of the local utility. The economic evaluation takes also into account the degradation of the battery performance along the years. The results, obtained in a future-price scenario, show that both the technologies entail a positive investment performance. However, vanadium flow batteries have the best results, given that they produce a net present value of up to 242% of the initial capital invested after 20 years, with a return on investment higher than 20%. In this scenario, the renewable share can reachup to 46%, compared to the current 26%.

  • 36.
    Lorenzi, Guido
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. Universidade de Lisboa, Portugal.
    Lanzini, Andrea
    Santarelli, Massimo
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. Politecnico di Torino, Italy.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Exergo-economic analysis of a direct biogas upgrading process to synthetic natural gas via integrated high-temperature electrolysis and methanation2017Ingår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 141, s. 1524-1537Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Biogas upgrading to synthetic natural gas (SNG) is a viable and appealing route for power-to-gas because it combines waste management with the use of the surplus electricity that might arise in energy systems having a considerable share of renewable energy sources in their production mix. In this work, the exergo-economic performance of a biogas upgrading process through integrated electrolysis and methanation is assessed in connection with the current market status to test which conditions could make the proposed option economically viable. Two different configurations, which differ mainly for the operating pressure of the electrolyser, are compared. The exergy efficiencies are high (>80%) and exergo-economic costs of the produced bio-SNG in the two analyzed configurations are 5.62 and 4.87 c(sic)/kWh(exergy), for low- and high-pressure respectively. Lower values would be required for the bio-SNG to compete with fossil natural gas. We show how both the input electricity price and the capacity factor have a substantial impact on the economic sustainability of the process. Eventually, the monetary exploitation of the oxygen produced by electrolysis and the participation to the emission trading scheme could contribute further to improve the economic attractiveness of the process.

  • 37.
    Lorenzi, Guido
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Vieira, Ricardo da Silva
    Univ Lisbon, Inst Super Tecn, Environm & Energy Sci Area, MARETEC LARSYS, Ave Rovisco Pais 1, P-1049001 Lisbon, Portugal..
    Santos Silva, Carlos Augusto
    Univ Lisbon, Inst Super Tecn, IN, Ave Rovisco Pais 1, P-1049001 Lisbon, Portugal..
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Techno-economic analysis of utility-scale energy storage in island settings2019Ingår i: Journal of Energy Storage, E-ISSN 2352-152X, Vol. 21, s. 691-705Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The decarbonization of the electricity supply in isolated and remote energy systems is an open challenge in the transition to a sustainable energy system. In this paper, the possibility to increase the penetration of renewable energy sources for electricity generation on the island of Terceira (Azores) is investigated through the installation of a utility-scale energy storage facility. The electric power dispatch on the island is simulated through a unit commitment model of the fossil and renewable power plants that has the objective of minimizing the cost of electricity generation. Battery energy storage is employed to partially decouple production and supply, and to provide spinning reserve in case of sudden generator outage. Two technological options, namely lithium-ion and vanadium flow batteries, are compared in terms of net present value and return on investment, with the aim of supporting the decision-making process of the local utility. The economic evaluation takes also into account the degradation of the battery performance along the years. The results, obtained in a future-price scenario, show that both the technologies entail a positive investment performance. However, vanadium flow batteries have the best results, given that they can produce a net present value that exceeds 430% of the initial capital invested after 20 years, with a return on investment higher than 35%. In this scenario, the renewable share can reach up to 46%, compared to the current 26%.

  • 38. Lucisano, M. F. C.
    et al.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Visualization of liquid-vapor phase change phenomena in impulse technology2006Ingår i: TAPPI Journal, ISSN 0734-1415, Vol. 5, nr 6, s. 15-21Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper addresses two unresolved aspects in the physics of impulse technology. In our initial study, we used a modified laboratory platen press to investigate contact phenomena at the interface between the wet web and the hot press. We replaced the heated press platen with a preheated glass plate and used high-speed photography to visualize the interfacial interactions. The results confirm that little or no steam is formed before the point of maximum applied load for contact times typical of industrial pressing operations (25 ms). Steam generation during the nip compression phase could be observed only for pulse lengths well beyond-those encountered in industrially relevant impulse press nips (250 ms). In a complementary study, flashing phenomena were investigated in STFI's FlashLab, an experimental facility for the study of phase-change phenomena in water-saturated porous media. Model experiments under well-defined conditions showed that delamination can be prevented by an appropriate unloading strategy. Moreover, we observed that flashing-assisted displacement dewatering occurred when the hydraulic pressure was released. We discuss its significance for impulse pressing efficiency in this report. Application: Insights from this study will help in the further development and possible commercialization of impulse drying systems.

  • 39. Lucisano, M. F. C.
    et al.
    Petrini, J. B.
    Martin, Andrew R.
    KTH, Tidigare Institutioner                               , Energiteknik.
    The role of evaporative dewatering in impulse pressing2003Ingår i: TAPPI Journal, ISSN 0734-1415, Vol. 2, nr 3, s. 26-32Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The objective was to link heat transfer to water removal mechanisms, specifically evaporative dewatering, in impulse pressing experiments. Two independent laboratory devices-a platen press and a shoe press-were used to impulse press fiber webs made from softwood bleached kraft (SBK) over a range of basis weights (20 200 g/m(2)). In the platen press experiments, evaporative dewatering was evaluated by comparing the measured heat input to the amount of heat theoretically required to vaporize the water in excess of unheated wet pressing. Evaporative dewatering was found to be most pronounced for lightweight sheets, and enhanced dewatering can be attributed to this mechanism and other high-temperature mechanisms for basis weights above 60 g/m(2). In the shoe press experiments, a composite sheet of five 30-g/m(2) webs was used to evaluate profiles for resulting dryness, density, and water retention value (WRV) in the thickness direction. Evaporative effects were confined principally to the layer directly in contact with the heated surface.

  • 40.
    Mainali, Brijesh
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Energi och klimatstudier, ECS.
    Hassan, Ahmed
    Khan, Ershad
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Silveira, Semida
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Energi och klimatstudier, ECS.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Addressing the rural energy and drinking water needs by using Biogas in rural Bangladesh2012Konferensbidrag (Övrigt vetenskapligt)
  • 41. Manna, A. K.
    et al.
    Sen, M.
    Martin, Andrew R.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Pal, P.
    Removal of arsenic from contaminated groundwater by solar-driven membrane distillation2010Ingår i: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 158, nr 3, s. 805-811Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Experimental investigations were carried out on removal of arsenic from contaminated groundwater by employing a new flat-sheet cross flow membrane module fitted with a hydrophobic polyvinylidenefluoride (PVDF) microfiltration membrane The new design of the solar-driven membrane module in direct contact membrane distillation (DCMD) configuration successfully produced almost 100 per cent arsenic-free water from contaminated groundwater in a largely fouling-free operation while permitting high fluxes under reduced temperature polarization For a feed flow rate of 0120 m(3)/h, the 013 mu m PVDF membrane yielded a high flux of 74 kg/(m(2) h) at a feed water temperature of 40 degrees C and, 95 kg/m(2) h at a feed water temperature of 60 degrees C. The encouraging results show that the design could be effectively exploited in the vast arsenic-affected rural areas of South-East Asian countries blessed with abundant sunlight particularly during the critical dry season.

  • 42.
    Martin, Andrew
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Fransson, Torsten H.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Gronli, Morten
    Bredesen, Arne M.
    SUSPOWER and ENGAS: Two major European research infrastructures in the gas turbine and energy conversion fields2006Ingår i: Proceedings of the ASME Turbo Expo 2006, Vol 1, 2006, s. 1015-1022Konferensbidrag (Refereegranskat)
    Abstract [en]

    Since the mid-1990's the European Commission (EC) has provided funding for transnational access schemes that open up existing major research facilities to outside users. In the current 6th Framework Program, two out of 14 funded projects - SUSPOWER and ENGAS - are of prime interest to the gas turbine community. SUSPOWER (KTH, Stockhom, Sweden) encompasses unique large-scale experimental facilities within the area of sustainable thermal power generation. Topics of key interest include high-temperature air combustion, catalytic combustion, gasification, aeroelasticity of turbine/compressor blades, film cooling aerodynamics, and stator/rotor interactions. ENGAS (NTNU, Trondheim, Norway) includes a complex array of specialized laboratories in the topic of environmental gas management. Relevant research topics include combustion of hydrogen and hythane, biomass gasification, CO2 absorption and sequestration, membranes for hydrogen and CO2 separation, gas storage in rock caverns, and hydrogen production and storage. This paper presents information on these projects along with a brief overview of previous EC transnational access activities as related to gas turbine research and development.

  • 43.
    Martin, Andrew
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Jonsson, Hans
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Tillämpad termodynamik och kylteknik.
    Martinac, Ivo
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Uthålliga byggnadssystem.
    Sustainable Energy Engineering:  An International Master Degree Program2002Ingår i: Proc. Engineering in Sustainable Development Conference, October 24th/25th 2002, Delft, The Netherlands, 2002, s. Paper no. 143-Konferensbidrag (Refereegranskat)
  • 44.
    Martin, Andrew R.
    et al.
    KTH, Tidigare Institutioner, Energiteknik.
    Drotz, M.
    Talja, R.
    Kaijaluoto, S.
    Puumalainen, T.
    Energy analysis of impulse technology: research-scale experimental papermaking trials and simulations of industrial applications2004Ingår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 24, nr 16, s. 2411-2425Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The impact of impulse technology on a system-wide level has been investigated in this study for non-integrated fine paper and linerboard mills. Impulse unit data were obtained from STFI's EuroFEX research paper machine and correlations were developed in order to predict performance (dewatering, electricity consumption) under commercial operating conditions. Mill analyses were conducted for different configurations (i.e. one or two impulse units with and without web preheating) operating with roll temperatures of 200-320 degreesC. Results show that the ingoing dryness to the dryer section can be increased within a wide span, from 7 to 27 percentage points depending upon the grade and operating parameters. Even though electricity consumption rises dramatically from the inductively heated rolls, overall fuel savings of up to 20% can be achieved with either one or two impulse units operating at 200 degreesC (external power plant efficiency assumed to be 45%). Impulse technology appears to be neutral in terms of production costs since increases in energy costs are expected to be counterbalanced by savings in feedstock materials and enhanced product quality. Estimates show that this technology can lead to substantial reductions in dryer section sizes for new installations or alternatively enhance productivity in existing paper machines.

  • 45.
    Martin, Andrew R.
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Lucisano, M. F. C.
    Characterizing liquid-vapor phase change phenomena in impulse technology with resistivity probes2006Ingår i: TAPPI Journal, ISSN 0734-1415, Vol. 5, nr 5, s. 22-26Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study used resistivity probes for the dynamic detection of liquid-vapor phase change inside wet paper webs undergoing impulse pressing. The probes were made from thin copper wires insulated with a high-temperature polymeric material (overall diameter-of 50 mu m). The gap between the exposed ends served as the probe tip. The validity of this technique in impulse pressing experiments was demonstrated in two ways: (1) tests with both dry and wet sheets showed that the probe response was unaffected by the fiber network itself; and (2) heated trials with low applied pressure and long residence times (> 1 s) clearly showed the propagation of a vapor front through the sheet, as predicted by theory. Impulse pressing, experiments were subsequently conducted with a platen press under realistic operating conditions (i.e. surface tempera tures up to 300 degrees C, nip residence times of approximately 25 ms, and maximum applied pressure around 4 MPa). Results show that steam was detected inside the sheet only upon unloading of the hot nip for the layers closest to the heated surface.

  • 46. Mohan, G.
    et al.
    Kumar, U.
    Pokhrel, M. K.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    A novel solar thermal polygeneration system for sustainable production of cooling, clean water and domestic hot water in United Arab Emirates: Dynamic simulation and economic evaluation2016Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 167, s. 173-188Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, a novel solar thermal polygeneration (STP) system for production of cooling, clean water and domestic hot water is modeled and analyzed for the weather conditions of United Arab Emirates (UAE). The system comprises of solar collectors for production of thermal energy, single stage LiBr-H2O absorption chiller (VAC) for providing air conditioning to office cabins and membrane distillation (MD) modules for clean water production along with domestic hot water generation as by-product. The performance of STP is analyzed with three different solar collectors - flat plate collectors (FPC), evacuated tube collector (ETC) and compound parabolic collector (CPC). The system is modeled and dynamically simulated using TRNSYS software for optimization of various design parameters like slope of the collectors, mass flow rate through the collector loop, storage capacity and area of collectors. Combined and system efficiency of the STP system has been determined for optimum conditions. Economic benefits are analyzed for different collectors and fuel costs savings. A lowest payback period of 6.75 years is achieved by STP with evacuated tube collector field having gross area of 216 m2. STP system has cumulative savings of $520,000 over the life time of the project through roof top solar collector installation. In terms of environmental benefits, 109 metric tons/year of CO2 emissions would be avoided and hence the overall payback period would be reduced by 8% based on cost saving through carbon credits. Economic and environmental benefits were aided by steady system performances of absorption chiller (35 kW), membrane distiller (80 l/day) and heat recovery system (1.2 m3/h) throughout the year. The complete simulation results of the STP system is utilized for the development, installation and testing of a polygeneration system at RAKRIC.

  • 47.
    Mohan, Gowtham
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi. CSEM UAE Innovat Ctr LLC, Swiss Ctr Elect & Microtechnol, Ras Al Khaymah, U Arab Emirates.
    Dahal, Sujata
    Kumar, Uday
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi. CSEM UAE Innovat Ctr LLC, Swiss Ctr Elect & Microtechnol, POB 31208, Ras Al Khaymah, U Arab Emirates.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Kayal, Hamid
    Development of Natural Gas Fired Combined Cycle Plant for Tri-Generation of Power, Cooling and Clean Water Using Waste Heat Recovery: Techno-Economic Analysis2014Ingår i: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 7, nr 10, s. 6358-6381Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tri-generation is one of the most efficient ways for maximizing the utilization of available energy. Utilization of waste heat (flue gases) liberated by the Al-Hamra gas turbine power plant is analyzed in this research work for simultaneous production of: (a) electricity by combining steam rankine cycle using heat recovery steam generator (HRSG); (b) clean water by air gap membrane distillation (AGMD) plant; and (c) cooling by single stage vapor absorption chiller (VAC). The flue gases liberated from the gas turbine power cycle is the prime source of energy for the tri-generation system. The heat recovered from condenser of steam cycle and excess heat available at the flue gases are utilized to drive cooling and desalination cycles which are optimized based on the cooling energy demands of the villas. Economic and environmental benefits of the tri-generation system in terms of cost savings and reduction in carbon emissions were analyzed. Energy efficiency of about 82%-85% is achieved by the tri-generation system compared to 50%-52% for combined cycles. Normalized carbon dioxide emission per MW.h is reduced by 51.5% by implementation of waste heat recovery tri-generation system. The tri-generation system has a payback period of 1.38 years with cumulative net present value of $66 million over the project life time.

  • 48.
    Mohan, Gowtham
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. American University of Ras Al Khaimah, United Arab Emirates.
    Kumar, N. T. Uday
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik. American University of Ras Al Khaimah,United Arab Emirates.
    Pokhrel, Manoj Kumar
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik.
    Experimental investigation of a novel solar thermal polygeneration plant in United Arab Emirates2016Ingår i: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 91, s. 361-373Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The demands for space air conditioning and clean drinking water are relatively high in Middle East North African (MENA) countries. A sustainable and innovative approach to meet these demands along with the production of domestic hot water is experimentally investigated in this paper. A novel solar thermal poly-generation (STP) pilot plant is designed and developed for production of chilled water for air conditioning using absorption chiller, clean drinking water with membrane distillation units and domestic hot water by heat recovery. The STP system is developed with a flexibility to operate in four different modes: (i) solar cooling mode (ii) cogeneration of drinking water and domestic hot water (iii) cogeneration of cooling and desalination (iv) trigeneration. Operational flexibility allows consumers to utilize the available energy based on seasonal requirements. Performance of STP system is analyzed during summer months in RAKRIC research facility. Energy flows in STP pilot plant during peak load operations are analyzed for all four modes. STP system with trigeneration mode utilizes 23% more useful energy compared to solar cooling mode, which improves overall efficiency of the plant. Economic benefits of STP with trigeneration mode are evaluated with fuel cost inflation rate of 10%. STP plant has potential payback period of 9.08 years and net cumulative savings of $454,000 based on economic evaluation.

  • 49.
    Navarathna, Nalin
    et al.
    KTH, Tidigare Institutioner                               , Energiteknik.
    Fedulov, Vitali
    KTH, Tidigare Institutioner                               , Energiteknik.
    Martin, Andrew
    KTH, Tidigare Institutioner                               , Energiteknik.
    Fransson, Torsten
    KTH, Tidigare Institutioner                               , Energiteknik.
    Web-based, interactive laboratory experiment in turbomachine aerodynamics2004Ingår i: Proceedings of the ASME Turbo Expo 2004, Vienna, 2004, Vol. 1, s. 885-891Konferensbidrag (Refereegranskat)
    Abstract [en]

    Remote laboratory exercises are gaining popularity due to advances in communication technologies along with the need to provide realistic yet flexible educational tools for tomorrow's engineers. Laboratory exercises in turbomachinery aerodynamics generally involve substantial equipment in both size and power, so the development of remotely controlled facilities has perhaps not occurred as quickly as in other fields. This paper presents an overview of a new interactive laboratory exercise involving aerodynamics in a linear cascade of stator blades. The laboratory facility consists of a high-speed fan that delivers a maximum of 2.5 kg/s of air to the cascade. Traversing pneumatic probes are used to determine pressure profiles at upstream and downstream locations, and loss coefficients are later computed. Newly added equipment includes cameras, stepper motors, and a data acquisition and control system for remote operation. This paper presents the laboratory facility in more detail and includes discussions related to user interface issues, the development of a virtual laboratory exercise as a complement to experiments, and comparative evaluation of Virtual, Remote and Local laboratory exercises.

  • 50.
    Navarathna, Nalin
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Fedulov, Vitali
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Martin, Andrew
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Fransson, Torsten
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Web-Based, Interactive Laboratory Experiment in Turbomachine Aerodynamics2010Ingår i: Journal of turbomachinery, ISSN 0889-504X, E-ISSN 1528-8900, Vol. 132, nr 1, s. 011015-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Remote laboratory exercises are gaining popularity due to advances in communication technologies along with the need to provide realistic yet flexible educational tools for tomorrow's engineers. Laboratory exercises in turbomachinery aerodynamics generally involve substantial equipment in both size and power, so the development of remotely controlled facilities has perhaps not occurred as quickly as in other fields. This paper presents an overview of a new interactive laboratory exercise involving aerodynamics in a linear cascade of stator blades. The laboratory facility consists of a high-speed fan that delivers a maximum of 2.5 kg/s of air to the cascade. Traversing pneumatic probes are used to determine pressure profiles at upstream and downstream locations, and loss coefficients are later computed. Newly added equipment includes cameras, stepper motors, and a data acquisition and control system for remote operation. This paper presents the laboratory facility in more detail and includes discussions related to user interface issues, the development of a virtual laboratory exercise as a complement to experiments, and comparative evaluation of virtual, remote, and local laboratory exercises.

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