För närvarande finns det ett stort intresse att utveckla ett ekonomiskt och framkomligt system för omvandling av biomassa till flytande bränslen och kemikalier, då hanteringen av bränslen väsentligt underlättas.

Under 2014, fick avdelningen för Energiteknik, KTH, uppdraget att undersöka och dokumentera KDVs process för konvertering av biomassa till flytande bränsle: Bland annat ingick att analysera processens produkt och restprodukter. Idag marknadsförs tekniken av Alphakat, Eppendorf, Tyskland. Alphakat gör gällande att KDV erbjuder en alternativ teknik för produktion av bränsle, inklusive syntetisk-diesel från fasta bränslen såsom biomassa. Det övergripande syftet med projektet var att samla information, tekniska data, processdata och genomföra test och analysera produkten. Detta för att få en uppfattning om huruvida KDV kan tekniskt användas föratt konvertera biomassa till diesel. Emellertid, KDVs tekniska potential, särskilt för omvandling av biomassa till flytande bränsle kunde inte bevisas baserat på resultaten av den nu aktuella undersökningen med den tillhandahållna informationen av företaget.

Produkten av processen analyserades enligt ASTM D6715. De relevanta egenskaperna för KDVs produkt dokumenterades genom noggranna tester. Men huruvida produkten kommer från biomassa kunde inte garanteras då KDV är en oljebaserad process. Påverkan av så kallade “Carrier oil”, på produktens kvalitet och kvantitet kan vara betydande då en stor del av värmevärdet hos bränslet kan komma från denna olja. KDVs potential för produktion av flytande bränsle från biomassa kan inte bevisas.

Vi bedömer att en fördjupad teknisk och vetenskaplig utvärdering av KDV är ett nödvändigt och viktigt steg för att framtiden underlätta kommande investeringar i KDVs teknologin. Denna utvärdering bör utföras i en laboratorieskala, med hjälp av avancerad mätutrustning, i en kontrollerad miljö som kunde garantera vetenskaplig dokumentation och övervakning av processen.

Förvätskning av biomassa ser vi som lovande då faktorer som medger attförnybara bränslen och kemikalier då kan göras tillgängliga för en allmän användning då de har en stor miljömässig fördel.

Converting CO2 and steam (H2O) into synthesis gas is a new route to recycle them to fuels. Conversions are performed via a two-step conversion method in which catalysts are heated up and cooled down repeatedly with CO and H2 as the products. To make the method economic, solar energy is employed to drive conversion systems. A solar-driven system with fluidized bed reactors is proposed for CO2 conversion in this paper, and numerical models are built to study its performance and find out the optimum working condition. The investigation proves that system is a competent candidate to power the two-step conversion of CO2 for the carbon recycle and the syngas production.

A model has been developed for thermodynamic cycle of the solar thermal production of power, heating and cooling utilizing nano fluid as a working fluid in Organic Rankine Cycle. The proposed working fluid provides enhancement in power, heating, and cooling as useful outputs. Initial studies were performed with silver-nano pentane as a working fluid in the cycle. This work extends the application of the cycle to working fluids consisting of organic fluid mixtures. Nano Organic fluid could be used successfully in solar thermal power plants, as working fluids in Rankine cycles. An advantage of using nano fluid as a working fluid is that there are mature experiences with building components for these fluids. A commercially available modeling program has been used to model and investigate the performance of the system. The potential and advantages of using nano fluid are discussed. It is found that the thermodynamic efficiencies achievable with nano organic fluid, under optimum conditions, are higher than those obtained from the base fluid. Further, the size of heat exchangers, evaporator, and condenser are lower than those using the base fluid.

In this work, a thermodynamic model based on theoretical and experimental data is developed for utilizing nano fluid organic Rankine cycle (nORC) in a trigeneration hybrid system. The trigeneration hybrid system composed of a solid biomass boiler, gas turbine cycle, a nORC, cooling, and a heating system. The exergy of the system analyzed; moreover, environmental impact assessments and interrelated parametric studies are examined. The results show higher exergy efficiency for the hybrid trigeneration employed nORC, and indicate that carbon dioxide emissions for utilizing nano fluid in nORC trigeneration system are less than conventional working fluid system.

KTH Royal Institute of Technology (KTH) is one of European’s key centers of innovation and intellectual talent for almost two centuries. Recognized as Sweden’s most prestigious technical university, KTH is also the country’s oldest and largest. Computerized simulation technique was recognized as a fundamental component of the higher-education sector at KTH as early as the fifties. Although the utilization of these tools in research is now considered to be standard, the educational aspects are not. In this field, the method of instruction followed by practice is considered to be a superior pedagogic method compared to lecture to many. The current method emphasizes on demonstrative activities of the learners known as phenomeno-graphic learning. However, phenomeno-graphic learning is viable if there are breadth and depth in the physic, mathematic, computer science and graphic, operational strategy and methodology, etc. illuminating weakness of learning by doing method.  

This work aims to report the success and progress of the course, numerical methods in energy technology, which utilizes Computational Fluid Dynamics cods such as STAR-CCM+ as the tool. Learning methodology is based on instructional design and andragogically approach that offers an elaboration on the mechanism of learning process and its premeditated in context of a prescribed framework. The results indicated the prominence of student sensitive and constructive learning process and the advantages of using a preferred framework in guiding the students in a pertinent context (area). The method particularly incorporates the constructivist principles that lead to enhance the learning process. In addition, the conclusions of this study similarly illuminate the vast potentials of computational fluid dynamic for research, evaluation and educational purposes.

The solar energy has been employed to provide the heat for CO2 conversions for several years except for its use on power generation, since it is one of the most common renewable energy resources and the total amount is enormous; However, the dominant method is to concentrate solar rays directly on reactants, relying on the design and quality of the receivers a lot. The operation and maintenance of the receivers require extra attention due to the delicate structure of the receivers and the potential contamination on the lenses from the chemical reactions. To steer clear of the shortcoming, a solar-driven catalytic reactor has been designed and analyzed in this article. The reactor drives the endothermic reactions with the heat source of hot gases, which are produced in solar receivers upriver, thus the flexible and necessary operations on the catalytic reactor could be peeled off from the solar receiver, and the potential contamination on the optical components in the solar receiver could be avoided. The design processes and details are described, the heat performance is simulated and analyzed, and efficiencies are theoretically calculated in this article. The solar-driven catalytic reactor exhibits the possibility of the practical use of solar energy in CO2 conversion and recycle.

Due to the challenges of demands on alternative fuels and CO2 emission, the conversion of CO2 has become a hot spot. Among various methods, two-step conversion of CO2 with catalyst ceria (cerium oxide, CeO2) appears to be a promising way. Solar energy is commonly employed to drive the conversion systems. This article proposes a solar-driven system with fluidized bed reactors (PER) for CO2/H2O conversions. N-2 is used as the gas of the heat carrier. The products of CO/H-2 could be further used for syngas. To evaluate the capability of the system for exporting work, the system was analysed on the basis of the Second Law of Thermodynamics and the reaction mechanism of ceria. Heat transfer barriers in practical situations were considered. The lowest solar to chemical efficiency is 4.86% for CO2 conversion, and can be enhanced to 43.2% by recuperating waste heat, raising the N-2 temperature, and increasing the concentration ratio. The analysis shows that the method is a promising approach for CO2/H2O conversion to produce syngas as an alternative fuel.