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  • 1. Budinova, T.
    et al.
    Ekinci, E.
    Yardim, F.
    Grimm, Alejandro
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Björnbom, Emilia
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Minkova, V.
    Goranova, M.
    Characterization and application of activated carbon produced by H3PO4 and water vapor activation2006Ingår i: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 87, nr 10, s. 899-905Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Activated carbons have been prepared from woody biomass birch by using various activation procedures: a) treatment with phosphoric acid and pyrolysis at 600 degrees C in inert atmosphere, b) the same as in (a) followed by steam activation at the same temperature and c) treatment with phosphoric acid and direct pyrolysis in a stream of water vapor at 700 degrees C. The surface area and the porosity of the activated carbons were strongly dependent on the treatment after impregnation with H3PO4 (pyrolysis in inert atmosphere, steam pyrolysis or combination of both). Activated carbon, prepared by impregnation with phosphoric acid followed by steam pyrolysis (steam activation) had highly developed porous structure and the largest surface area among all prepared carbons (iodine number 1280 mg/g and BET surface area 1360 m(2)/g). The adsorption capacity of this sample for Hg(II) from aqueous solution was studied in varying treatment conditions: contact time, metal ion concentration and pH. The adsorption followed Langmuir isotherms and the adsorption capacity for Hg(II) at 293 K was 160 mg/g.

  • 2.
    Grimm, Alejandro
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Environmentally friendly utilization of biomass2007Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The thesis deals with various ways of utilization of biomass. Chapter 1 compares three biomass types: birch wood Betula sp., marine brown alga Fucus vesiculosus, and terrestrial moss Pleurozium schreberi, as precursors for preparation of biosorbents for removal of copper ions from diluted water solutions. Small sample doses (0.5 g/100ml) of the biosorbents prepared from alga and moss enabled more than 90 % removal of Cu (II) ions from diluted water solutions (5-20 mg/l). The sample from birch wood was less effective. The maximum sorption capacities (Xm) determined from the experimental equilibrium isotherms by applying the Langmuir model showed that the alga had the best copper-binding ability (Xm = 23.4 mg/g), followed by the moss (Xm = 11.1 mg/g), and the sawdust (Xm = 4.9 mg/g). The performance of the biosorbent prepared from birch was not satisfactory. The regeneration of the sorbents from alga and moss was performed using diluted HCl as eluent. No visible damages or performance losses were detected after five sorptiondesorption cycles.

    Chapter 2 deals with MnOx-Pd/Alumina-La catalysts for abatement of the emissions from wood combustion. Of primary interest is the calcination temperature used in preparation of the catalysts. Several catalysts are prepared using various calcination temperatures, 500, 600, 700 and 800 oC for 4 h in air and their activities and stabilities are compared. The activity tests were performed using gaseous mixtures containing combustibles representative for the flue gases from wood combustion, carbon monoxide (2500 ppm), methane (200 ppm) and naphthalene (50 ppm). The catalytic oxidation tests were performed in presence of 10 % O2, 12 % H20, 12 % CO2 and N2 (balance). The concentrations of the components in the gaseous mixture and the total flow of the mixture correspond to those in the flue gases from combustion (gas flow 2.5 l/min corresponding to a space velocity of approximately 20000 h-1). In presence of the catalysts carbon monoxide (CO) and naphthalene (C10H8) ignite almost simultaneously in the interval 150-200 ºC and are totally converted at temperatures a little above 200 ºC. The light-off temperatures of methane (CH4) are in the interval 600-650 ºC, and total conversion is reached at around 700 ºC. The most suitable calcination temperature for the catalysts prepared here is 700 ºC. Lower temperatures, 500 and 600 ºC, seem to result in formation of less stable catalysts. The catalysts calcined at higher temperature, 800 ºC, have stable performance in repeated tests, but lower activity.

    Chapter 3 presents results from literature study on corrosion and deposit formation in combustion of biofuels. Contributing to understanding the reasons for corrosion and the methods for its abatement are the primary goals. The scope is limited to deeper insight of the role of chlorine and alkali in combustion of biomass and the possibilities for hampering their corrosive effects. The role of additives decreasing the corrosion and deposit formation as well as the effect of water and the prospective for availability of low-chlorine biofuels have also been examined.

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  • 3.
    Grimm, Alejandro
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Górdon, M.
    Zanzi, Rolando
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik. KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk teknologi.
    Björnbom, Emilia
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Catalytic oxidation of combustibles representative of flue gases from wood combustion2005Konferensbidrag (Refereegranskat)
  • 4.
    Grimm, Alejandro
    et al.
    KTH, Tidigare Institutioner, Kemiteknik. KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Pérez Gordón, Maria
    Zanzi, Rolando
    KTH, Tidigare Institutioner, Kemiteknik. KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk teknologi.
    Björnbom, Emilia
    KTH, Tidigare Institutioner, Kemiteknik. KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Laboratory tests of catalysts for total oxidation of combustibles representative for flue gases from combustion of wood2004Konferensbidrag (Refereegranskat)
  • 5.
    Grimm, Alejandro
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Suarez, José
    Facultad de Ingeniería Mecánica, Universidad de Oriente. Santiago de Cuba, Cuba.
    Björnbom, Emilia
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Zanzi Vigouroux, Rolando
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Preliminary tests with a birch wood pellets up-draft air gasifier2004Ingår i: International Scientific Conference of Mechanical Engineering, 2004Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    In Sweden and Cuba a variety of biomass have being investigated for energyconversion through termochemical processes into solid, liquids and gaseous products. Biomass gasification in fixed bed seem to be attractive option for the conversion ofagricultural and forest residues into gases suitable for use as alternative fuel in gasengines in rural areas, heat or electricity production.

    This paper discusses the performance characteristics of a up - draft gasifier withBirch wood pellets. The bench scale gasifier was designed and built in the Royal Istitute of Technology, Sweden.

    A series of parameters, such as the gas and liquids yields, temperatures and ash yield were measured as a function of the time.

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  • 6.
    Grimm, Alejandro
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Zanzi, Rolando
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Björnbom, Emilia
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Cukierman, A. L.
    Tecnología Especial, Depto Tecnología Farmacéutica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires.
    Comparison of different types of biomasses for copper biosorption2007Ingår i: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 99, nr 7, s. 25559-2565Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Three biomass, birch wood Betula sp., marine brown alga Fucus vesiculosus, and terrestrial moss Pleurozium schreberi, have been compared as raw materials for preparation of biosorbents for removal of copper ions from diluted water solutions. Small sample doses (0.5 g/100 ml) of the biosorbents prepared from alga and moss enabled more than 90% removal of Cu(II) ions from diluted water solutions (5-20 mg/l). The sample from sawdust was less effective.A pseudo-second-order rate model properly described the experimental kinetic data for the biosorbents. The maximum sorption capacities (X,) determined from the experimental equilibrium isotherms by applying the Langmuir model showed that the alga had the best copper-binding ability (X-m = 23.4 mg/g), followed by the moss (X-m = 11.1 mg/g), and the sawdust (X-m = 4.9 mg/g). No visible damages or performance losses were detected for the alga and moss after five sorption-desorption cycles using diluted HCl as eluent.

  • 7.
    Zanzi Vigouroux, Rolando
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk teknologi.
    Björnbom, Emilia
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Grimm, Alejandro
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Biosorbentes para la remoción de cobre (II) en soluciones acuosas2005Konferensbidrag (Refereegranskat)
  • 8.
    Zanzi Vigouroux, Rolando
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Björnbom, Emilia
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Soria, Santiago
    Dept. of Chemical and Environmental Engineering, Univ. of Zaragoza, Spain.
    Grimm, Alejandro
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    FIXED BED UPDRAFT GASIFICATION OF BIOMASS2005Ingår i: 14th European Biomass Conference and Exhibition, ETA-Florence, Italy and WIP-Munich, Germany , 2005Konferensbidrag (Refereegranskat)
    Abstract [en]

    The paper presents the initial work performed in a newly built updraft gasifier. Densified woody biomass, birch, in form of pellets with a diameter of 8 mm and a length between 5 and 15 mm has been used as a raw material for batch autothermal gasification using air as an oxidation agent. The main objectives were to study the effect of the treatment conditions on the distribution of the products and the composition of product gas to establish the suitability of the gasifier to produce combustible gas with sufficiently high calorific value.The amount of the biomass used in the experiments was varied between 1 and 4 kg and the flow rate of the oxidation agent, air, was varied from 1,1 to 2,6 m3/h. Increased airflow rates favored higher temperatures, however, excessively high airflow rates resulted in fast consumption of the biomass and it also favored combustion over gasification and thus formation of lower amounts of combustible products. High airflow rates caused also higher yields of liquid products, due to the shorter residence time of the tar-rich gas in the gasifier and thus unfavorable conditions for tar cracking.

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  • 9.
    Zanzi Vigouroux, Rolando
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk teknologi.
    Grimm, Alejandro
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Kemisk reaktionsteknik.
    Fixed (slow-moving) bed updraft gasification of agricultural residues2006Konferensbidrag (Refereegranskat)
    Abstract [en]

    A laboratory-scale countercurrent fixed-bed gasifier has been designed and constructed to produce datafor process modelling and to compare the gasification characteristics of several biomasses. Densified woodybiomass, birch, in form of pellets with a diameter of 8 mm and a length between 5 and 15 mm has been used as a rawmaterial for batch autothermal gasification using air as an oxidation agent. The main objectives were to study theeffect of the treatment conditions on the distribution of the products and the composition of product gas to establishthe suitability of the gasifier to produce combustible gas with sufficiently high calorific value. The influence of theair flow rates on the composition of the producer gas has been studied. The amount of the biomass used in theexperiments was varied between 1 and 4 kg and the flow rate of the oxidation agent, air, was varied from 1,1 to 2,6m3/h.

  • 10.
    Zanzi Vigouroux, Rolando
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Grimm, Alejandro
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik.
    Soria, Santiago
    Deptamento de Ingeniería Química y Tecnologías del Medio Ambiente, Universidad Zaragoza.
    Gasificación de pellets de madera en un reactor en flujo ascendente2006Ingår i: Revista Ciencias Exatas, ISSN 1516-2893, Vol. 12, nr 1, s. 63-69Artikel i tidskrift (Refereegranskat)
    Abstract [es]

    El trabajo presenta los resultados de la gasificación de madera pelletizada de abedul en un reactor discontinuo de lecho ascendente. En los experimentos realizados se cargo el gasificador y se realizo el ensayo sin volver a alimentar el gasificador. Es decir se gasificó solo una carga. Se varió la carga utilizada (3 y 4 kg de madera pelletizada) y el flujo de aire (entre 1.1 m3/h y 2.6 m3/h). El gas producido por la gasificación esta compuesto de CO2, CO, H2, CH4 y hidrocarburos livianos. Las mayores concentraciones de los gases producidos por la gasificación y ricos en energía son 19% de CO, 7% de H2, 4 % de C4, y 1% de hidrocarburos livianos [C2 (etano, eteno y acetileno)]. El efecto predominante del aumento del flujo de aire es una mayor temperatura en el gasificador. El proceso de gasificación mejora debido a una mayor temperatura y a un aumento de la cantidad de dióxido de carbono producida por una mayor combustión. A mayor velocidad de gasificación aumenta la producción de monóxido de carbono y el contenido calorífico del gas producido es mayor. La cantidad de líquidos aumenta con el flujo de aire.

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