Biomass utilization for the process of gasification

SPĚVAK, J., HAVLICEK, M.: Biomass utilization for the process of gasifi cation. Acta univ. agric. et silvic. Mendel. Brun., 2008, LVI, No. 2, pp. 147–156 Biomass as one of the renewable resources of energy has bright future in utilization, especially in obtaining various forms of energy (heat, electrical energy, gas). According to the conception of energy policy of the Czech Republic and according to the fulfi llment of the indicators of renewable resources using until the year 2010, the research of thermophysical characteristics of biofuels was realized. There were acquired considerable amount of results by combustion and gasifi cation process on the basis of three-year project „Biomass energy parameters.” By means of combustion and gasifi cation tests of various (biomass) fuels were acquired the results which were not published so far. Acquired results are published in the fuel sheets, which are divided into four parts. They consist of information on fuel composition, ash composition, testing conditions and measurand overview. Measurements were realized for the process of combustion, fl uidized-bed gasifi cation and fi xed-bed gasifi cation. Following fuels were tested: Acacia, Pine, Birch, Beech, Spruce, Poplar, Willow, Rape, Amaranth, Corn, Flax, Wheat, Saffl ower, Mallow, and Sorrel. biomass, gasifi cation, pyrolysis, renewable resources, gasifi er tests, pellets, briquettes At present, the concern about biomass utilization grows in order to acquire various kinds of energy. The aim at the development of the biomass processing technologies is to attain the high operational reliability, performance, low operating costs and low capital expenditure. It is still to solve the matter of reducing injurants wasting the atmosphere. When solving these problems, it is not suffi cient just to know only basic biomass parameters, such as heating value, which is dependent on the water content. It is important to know also other parameters, which aff ect the transformation process in a given machinery. However, no suffi cient database of these parameters so far exists and also important is the fact that biofuels quality if aff ected by the area of their growing, too, i. e. soil type, fertilization, climatic effects, etc. For the illustration, from the total quantity of the fuel samples I am introducing the values and results of one of the fuel sample – rape – from the three processes. MATERIAL AND METHODS MEASUREMENT METHODOLOGY In this methodology is described the measurement procedure and which objectives were to solve. The part of this methodology is the operation process while experimental method data mining while biomass gasifi cation. Measurement 1.1 For each measurement it is necessary to fi nd out the following information: • fuel composition and characteristic (in our case particular biomass types) • operating parameters (temperature, pressure) • input and output materials fl ows (fuel, air, gas, ash) • output gas composition. At fi rst, each fuel type was analyzed; this analysis contained the following values: • low heating value, high heating value 148 J. Spěvak, M. Havlicek • proximate analysis (water content, ash content, fl ammable matters, volatile fl ammable matters) • ultimate analysis (C, N, O, H, S, Cl) • bio-chemical analysis (tannins, residuous compounds, lignin, holocellulose) • characteristic ash temperatures (deformation temp., sphere temp., hemisphere temp., fl ow temp.) • ash composition (P2O5, Al2O3, Na2O, SO3, SiO2, CaO, K2O, Fe2O3, MgO, TiO2, MnO,Cl, Pb, Cd, Cu, Hg, Cr, Ni, V, Zn). The spot fuel samples were analyzed in the accredi ted laboratories. Their brief characteristics and analy sis methodology is mentioned in the text below. Proximate and ultimate analysis of fuels and ash composition stated the accredited laboratory No. 1060 TUV NORD Czech, Ltd., Analytical Chemistry Laboratory, characteristic temperatures of ashes stated partly already mentioned laboratory TUV NORD Czech, Ltd., and the Brown Coal Research Institute, j. s. c., in Most. The bio-chemical analysis of fuel samples was done by the Department of Wood, Pulp and Paper at Faculty of Chemical Technology of University of Pardubice. Measuring procedure 1.2 For the measurement is stated the methodology, by course of it is proceeded and by course of it the spot operations are being done. • Fuel sampling for physiochemical analysis While fuel sampling the conventions according to Czech government standards CSN 44 1301 and CSN 44 1304 were followed. More sampling at various places of fuel storage was made; the sample consisted of sizes with various fractions. • Declaring the row material specifi c value The evergreen tree species samples were during the fi xed-bed gasifi cation tests dosed in the form of lump wood at sizes lower than 20 cm and of maximum humidity 20 %. Culm plants, except of amaranth, mallow and saffl ower, were gasifi ed in the form of pellets or briquettes. Amaranth was able to gasify in the form of shreddings and it was not need to modify it. It was unable to use mallow and saffl ower in the form of pellets, however the gasifi cation of shreddings from these two products was not successful. As supposed, the shreddings are not suitable for this type of gasifi cation generator. The fuel was supplied mainly in the form of pellets and briquettes – see Fig. 1 and Fig. 2 – as well as in the form of piece material. The illustration of waste – ash – is at the Fig. 7. 1: Fuel – pellets 2: Fuel – briquettes 3: NH3 and Cl gas-meter 4: Computer output Biomass utilization for the process of gasifi cation 149 5: The detail of analog instrument 6: Analog emissions instrument