18 Energy conversion and recycling

In the system, coal ash generated from boilers is monitored to measure specific values for fractionation before reaching to non-fractionated storage means and a part of the ash satisfying properties is directly transferred to storage areas of fractionated ash. Directly reusable ash without fractionation is not mixed with other ash in the system.

As the resource to voluntary action grows wider, a question must be held on the factors that influence the performance of a Voluntary Agreement as an environmental policy instrument. Our goal in this paper is to answer that question, outlining the main variables that make a Voluntary Agreement simultaneously efficient, effective and just. Using several articles on the subject of voluntary action, under the themes of ‘economic regulation’ and of contracts under ‘asymmetric information’, as well as available reports on the Portuguese and European experience on the use of Voluntary Agreements, we will undertake this objective following three steps: (i) underlining the main factors that justify the private and public option for Voluntary Action, (ii) presenting an analysis of the co-regulation process under the requirements of the three E criteria: efficiency, effectiveness and equity, (iii) finally concluding by presenting an ‘evaluation table’ that summarizes the elements that we found to be the most important for the ‘performance’ of the voluntary action in each one of those criteria.

18 ENERGY CONVERSION AND RECYCLING

02/01225 Biogeochemical and ecological considerations in designing wetland treatment systems in post-mining landscapes Kahn, M. Wrrsre Manu,cemen!, 2001, 21, (2), 191-196. Although wetlands have gained acceptance as important components of ecosystems in post-mining landscapes in the past decade, their roles in contaminant retention/removal have not been well integrated into the designing of restoration programs. This paper describes the integration of sediment microbial activities and natural precipitation processes, along with approaches to defining the contaminant load from the mine wastes. The contaminant removal rates, which can be expected by a wetland sediment, are summarized and how they need to be reflected in the wetland size required, and the carbon supply which is needed. Contaminant loading from mining wastes can be balanced by wetland ecological processes, including wetland primary production and microbial mineralization in the sediment. This ecological engin- eering approach is demonstrated using case studies on hard-rook mining waste in Canada.

02/01226 Chlorine removal from a mixture of waste plastics as a condition for their use for energy manufacture and for use as recycled material Sobolewski, A. e/ ul. Ochr. Powietrx Pro/d. Oldpadow, 2000, 34, (S), 1X3-188. (In Poland) Effect on thermal utilization of PVC presence in waste plastics is discussed. The thermal processing of waste plastics by thermolysis in bitumen is characterized. Results of experiments concerning the thermal decomposition of waste plastics in coal tar pitch carried out under different conditions are also discussed. The effect of time and final temperature of thermolysis of waste plastic on the chlorine content in the final solid product was determined. The thermolysis in bitumen is recommended as the method of waste plastics processing to obtain a semi-finished product which can used as fuel in power plants, for coking, and chemical industry.

02/01227 Clean combustion of coal, utilization of byproduct from the combustion, and products thereof Zheng, C. and Zheng, D. PCT Int. Appl. WO 01 30,944 (Cl. ClOL9/10), 3 May 2001, CN Appl. 2,000,103,328, 6 Mar 2000. 36. (In Chinese) Coal is mixed with a clean combustion aid containing activated SiOz, by grinding with the aid to form ‘affiliated particles’ by adsorption, and burnt in a suspended condition in furnace; where the aid contains activated SiOz containing material l-50, quick lime 5-98, carbide slag O-80. Fe rich material O-10, P containing material O-10, elec. phosphorus slag O-5, and desulfurization catalyst O-5 parts and the aide is mixed at 6-55 parts with 50-95 parts powdered coal. The clean combustion aid reduces emission of SO,, No, CO and COz during coal burning. The byproduct contains CzS 5-75, CsA l-40, CsAF l-40 parts and has ignition loss O-5 parts. The combustion byproduct is used as reinforcing agent in cement.

02/01226 Coal ash treatment system with improved reusability Komatsu, Y. cl N/. Jpn. Kokai Tokkyo Koho JP 2001 116,238 (Cl. F23JI/O2), 27 Apr 2001, Appl. 1999/292, 160. 14 Ott 1999. 6. (In Japanese)

02/01229 Composition of recycle oil helps determine coke yield Li, X. and Lin, R. Oil Gus J., 2001, 99, (IO), 6466. A method to determine the composition and coke yield of recycle oil in delayed coking was described. The method estimates the subfraction content and cut fraction distribution of the coking feedstock. That is, it estimates the content of the heavier hydrocarbons that come off the bottom of the fractionator to be recycled to the furnace. To show the effect of throughput ratio (TPR) on coke yield, coking experiments of feedstock with varied TPR were also conducted.

02/01230 Fuel treatment systems Murata, K. et crl. Jpn. Kokai Tokkyo Koho JP 2001 115,174 (Cl. ClOL3/10), 24 Apr 2001, Appl. 1999/294,078, I5 Ott 1999. 16. (In Japanese) The systems have a means supplying a raw fuel slurry, a reactor generating a fuel gas by a hydrothermal reaction of the slurry, and a means separating the fuel gas from remaining solid and water. The raw fuel may be biomass, wastes, and coal.

02iO1231 Long-term effects of intercropping and bio-litter recycling on soil biological activity and fertility status of sub-tropical soils Manna, M.C. and Singh, M.V. Bioresource Technolog,v, 2001, 76, (2), 143-150. On-farm field experiments were carried out at two sites having 38- and lo-year-old orchard cropping systems under sub-tropical climatic regions to evaluate changes in organic carbon accumulation and chemical and microbiological properties of the soils. Under a system of different intercropped fruit trees, the cultivating of coconut (Cocos nucifero L.) intercropped with guava (Psi&m guujuvu L.) enhanced the soil microbial activity approximately 2-fold after 38 years over IO years of the same mtercropped system. Soil organic carbon increased from 3.4 to 7.8 and 2.4 to 6.2 g kg ’ after 38 years and IO years, respectively, following the establishment of orchards. The increase was attributed to greater recycling of bio-litters. Levels of dehydrogenase, phosphatase and soil microbial biomass under field conditions generally depended more on the nature of the cropping system than on soil types. Similarly, average carbon inputs of bio-litter to the soil in monocrop (0.98 Mg ha year ) was less than intercropped fruit trees (2.07 Mg ha year -). The average level of soil microbial biomass carbon was I I58 kg ha- (O- 0.15 m depth) and the organic carbon turnover rate was 8.5 year- after 38 years of intercropped fruit trees, which resulted in a lower ratio (I .8 I) of carbon inputs to soil microbial biomass carbon.

02lO1232 Method for removing sulfur oxides from flue gas by using waste residuals from soda plant Wang, Q. Faming Zhuanli Shenqing Gongkai Shuomingshu CN 1,268,387 (Cl. BOlD53/50), 4 Ott 2000, Appl. 99,112,131, 29 Mar 1999. 4. (In Chinese) The method comprises allowing flue gas to contact with the white slurry from soda plant in a reactor. The reactor is spray absorption tower, Venturi absorption tower, packed absorption tower, bubble absorption tower, sieve-plate absorption tower, column tray type absorption tower, or moving-bed absorption tower. The white slurry is prepared from the residue and seawater or fresh water, and the solid content is lo-20%. Fly ash and lime may also be added to the white slurry.

02/01233 Organic matter components and aggregate stability after the application of different amendments to a horticultural soil Albiach, R. et rrl. Bioresource Technology, 2001, 76, (2), 125-129. The effects of usual or recommended rates of application of five organic amendments (24 t/ha year of MSW compost, sewage sludge, and ovine manure, 2.4 t/ha year of commercial vermicompost, and 100 l/ha year of a commercial humic acids solution) on the soil contents of organic matter, total humified substances, humic acids, carbohydrates and microbial gums, and the structural stability of aggregates were investigated. Four and five years after the beginning of the experiment, significant increments in most of the parameters studied were found after the application of organic residues, whereas the two commercial amendments did not produce any significant change, suggesting that rates recommended by the producers and imposed by their high prices are too low to be useful. MSW compost yielded the highest increases, even if the amount of organic matter applied as ovine manure was very similar. Organic matter and carbohydrates appeared to be the parameters most closely related to soil aggregate stability.

Fuel and Energy Abstracts March 2002 151