Co-composting of sugarbeet vinasse: influence of the organic matter nature of the bulking agents used

07 Alternative combustion. Five fuels were used in the study consisting of three reed canary-grass samples with different ash contents from different growing sites in Sweden and additionally one of these materials was separated into a stem and leaf fraction. Flue gas emissions were measured and fuels and ashes were analysed. The variation in ash content did not affect the production of briquettes. Further, fuel containing only stem fraction showed the highest mechanical strength. The variation in ash content did not effect the flue gas emissions. The presented results showed low mean values for carbon monoxide (< 42 mg/MJ, except one experiment) and particles in the flue gas (< 150 mg/ Nm’) (no purification of flue gas). Emissions of nitrogen oxides were < 110 mg/MJ. The ash formed light voluminous big chunks where small parts showed a tendency to be sintered. The combustion experiments imply that spring-harvested reed canary-grass can be burned with success in combustion equipment that is designed for the differences in ash content. W99972 Carbon balance of sugarcane bioenergy systems Beeharry, R.P. Biomuss md Biomerg~, 2001, 20, (5), 361-370. An important criterion for hioenergy systems evaluation is their greenhouse gas mitigation potential. Sugarcane hioenergy systems are able to produce grid-hound surplus electricity but also have net COz emissions associated with the upstream fossil-fuel consumption for plantation management, transportation and processing of the fibrous biomass. However, when compared to coal-based power generation systems, sugarcane hioenergy systems are able to avoid COz emissions at rates that range between 1.081 and 1.137kg COz/k Wh depending on the cane-residue utilization strategy adopted. As a consequence, sugarcane bioenergy systems stand out as promising energy projects for funding under the Kyoto Protocol’s proposed clean development mechanism and joint implementation. 02lOO973 Co-cornposting of soybean residues and leaves in Hong Kong Wong, J.W.C. el rrl. Bioresource Trchnologp, 2001, 76. (2) 99-106. The goal of this project was to evaluate the feasibility of co-composting of soybean residues and leaves and the effects of turning frequency on compost quality. Soybean residues were mixed with leaves and sawdust in 1:1:3 (w/w wet weight) for achieving a C/N ratio of about 30. Three heaps of about 4 m3 of compost mixtures were prepared receiving a turning frequency of daily (pile A), 3-day (pile B) and weekly (pile C) turning. Different turning frequencies did not significantly affect the changes in pH and volatile solids throughout the composting period. High turning frequency caused a lower electrical conductivity and NH4N contents as well as a shorter duration of thermophilic phase, because of a high heat loss by evaporation and volatilization of ammonia in the pile. The highest C decompostion of 4% occurred in the pile with a 3day turning period, which coincided with the higher-nitrogen content in this treatment. All treatments with different turning frequencies reached maturation at 63 days as indicated by the soluble organic carbon, soluble NH,-N, C/N ratio and cress seed germination index. However, increasing the aeration during composting period was beneficial in accelerating the maturation process. Taking into consideration less labour and lower operation costs as compared to daily turning, it can he suggested that a 3-day turning frequency would be more appropriate for reaching acceptable quality of compost and ease in operation. 02/00974 Co-composting of sugarbeet vinasse: influence of the organic matter nature of the bulking agents used Madejon, E. et al. Eioresourcr Tcdmolog~, 2001, 76, (3), 2755278. Two composts were obtained by co-composting of a concentrated depotassified beet vinasse and two agricultural solid residues with different organic matter nature: grape mart (GM; lignin waste) and cotton gin trash (C; cellulosic waste). Composting was carried out in aerated piles with mechanical turning, in controlled conditions during 4 months. After 71 days of composting, a new addition of vinasse similar to the initial addition was made. Changes in temperature, pH and inorganic nitrogen followed a similar path for both mixtures. However, organic matter fractions showed different behaviour depending on the material co-composted with vinasse. Lower organic matter degradation was observed when GM was used as bulking agent due to its high lignin content. No phytotoxicity was detected in the end products. The chemical and physical properties of both vinasse composts suggest their possible use as fertilizer. 02/00975 Comparison of moist vs. air-dry biomass provision chains for energy generation from annual crops Heinz, A. er crl. Biornuss und Bioenrrg~, 2001, 20, (3) 197-215. Animal crops for energy generation from agriculture are usually processed as cereal bales with air-dry biomass. As a promising alternative a novel concept of moist biomass has been developed. In this concept biomass is produced in a ‘double-cropping system’ and processed via ensiling and mechanical dehydration. The aim of this paper is to describe the concept of moist biomass provision in

energy sources (bioconversion

energy)

comparison with air-dry biomass provision. To assess the advantages and disadvantages of .the two concepts, they are compared with each other regarding environmental and economic aspects. The methodological approaches used as well as selected results are presented. Among others, the results show that the provision of moist biomass could be advantageous concerning some environmental aspects but the energy provision costs are significantly higher. 02lOO976 Continuous acetone-ethanol-butanol fermentation by immobilized cells of Closfridium acetobutykum Badr, H.R. er al. Biomm~ and Bioenerg~, 2001, 20, (2), 119-132. Eight Closrridium crcerohu/~/icum strains were examined for a-amylase and strains B-591, B-594 and P-262 had the highest activities. Defibered-sweet-potato-slurry (DSPS), containiyg 39.7 g starch I- , supplemented with potassium phosphate (I .O g I ), cys\eine-HCI (5.0 g I ), the antifoam (polypropylene glycol, 0.1 mg mll ), was used as continuous feedstock (FS) to a multistage bioreactor system for acetone-ethanol-butanol (AEB) fermentation. The system consisted of four columns (three vertical and one near horizontal) packed with beads contaming immobilized cells of C. ace/ohu/ylicum P-262. When DSPS was pumped into the bioreactor system, at a flow rate of 2.36 ml min , the effluent had 7.73 g solvents I (I .56, acetone; 0.65, ethanol; 5.52 g, hutanol) and no starch. Productivity of total solvents synthesized during continuous opemtion were 1.0 g I-’ h-’ and 19.5% yield compared to 0.12 g I h ’ wrth 29% yield using the batch system. DSPS was proposed for AEB fermentation in a continuous mode with immobilized P-262 cells that are active amylase producers which will lead to cost reduction compared to the hatch system. 02lOO977 Conversion of cotton cocoon shell to liquid products by supercritical fluid extraction and low pressure pyrolysis in the presence of alkalis Caglar, A. and Demirbas, A. Energy Conversion and Mmcrgemenr, 2001, 42, (9) 1095-I 104. Ground cotton cocoon shell was converted to liquid products by supercritical fluid extraction (SFE) using acetone and water as solvents and NaOH, NazCOs, KOH and KzCOs as alkalis in an autoclave at temperatures of 508,523, 543, 563,583,623 and 650 K. The yields from SFE with acetone were 35.6% at 508 K and with water were 69.1% at 653 K. The yields from liquefaction with water were 80.2% and 86.2% using NaOH and KOH (sample-to-alkali ratio was 1:l) at 573 K for 30 min, respectively. The oxygen contents of the products were 22.9% and 28.9% from the extractions (at ~491 K) and the low pressure pyrolyses (at range of 439-469 K), respectively. The maximum yield of product was obtained from the water extractions with KOH additive. The maximum yields of extracts increased from 56.5% to 89.6% obtained from the water extraction runs with 100% KOH additive at the temperature range of 508-653 K. 02/00978 Development of fuel production technology from biomass resources Fukuda, H. Eco Ind., 2000, 5, (2), 5514. (In Japanese) A review with eight references. A process of biodiesel fuel production from plant oil is proposed using methanolysis with lipase. Two useful technologies for this are described. One is an intelligent bioreactor based on immobilization of yeast with porous polyurethane support. The utility of this bioreactor is verified for conversion from acetanilide to p-acetaminophene with P 450 mono-oxygenase. The other is expression of hetero-gene on the cell using signal sequence and GPI anchor attachment signal sequence found in n-agglutinin from yeast. 02/00979 Evaluating the feasibility of biomass pyrolysis oil for spray combustion applications Krumdieck, S.P. and Daily, J.W. Combus/. Sci. Techno/, 1998, 134, (I6), 351-365. Current fuel conversion technology is a result of decades of experience with fossil fuels. The liquid fuels derived from the pyrolysis of biomass are significantly different from fossil fuel oils. The chemical and physical properties of typical pyrolysis oils were investigated and compared to fossil fuels. Special fuel handling requirements for the hio-oil were incorporated into a fuel delivery system design and a laboratory scale spray combustor system was constructed. The implications of the viscosity and surface tension on the atomization were analysed, leading to an experimental combustion chamber and air swirler design. Hot-gas filtered pyrolysis oil made from poplar wood at NREL was used in the combustion experiments. Emissions were monitored and CFR 40 part 60 methods were used to sample stack gas. These results were used to determine optimal operating conditions. It was concluded that, within specific constraints, an industrial size boiler or furnace could be constructed and operated to reliably burn pyrolysis oil. The boiler, when operating at optimal combustion conditions, would not violate the US Clean Air Act emissions standards (as currently proposed). Fuel and Energy Abstracts

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