Showing papers on "Biogas published in 1977"

Apparatus for the production of methane containing gas by hydrogasification

Abstract: An improved system for producing methane-containing product gas by the hydrogasification process. With the system, solid municipal waste is comminuted and dried following which it is introduced to the lock hopper receivers for transference to an elongate hydrogasification reactor. Synthesis gas is introduced to a lower region of the reactor and the comminuted waste, including inorganic materials, is dried and converted to methane-containing product gas and char. The char is removed from the system by a variety of separation systems including cyclone separators or aspirators and the inorganic fractured waste materials pass through the reactor but are undamaged and in a sterile condition ideally suited for recovery. A gasification reactor is incorporated with the system which receives char from the process as well as oxygen to produce the synthesis gas utilized in the hydrogasification reactor. Where no inorganic materials are present, the organic materials may be introduced both to the gasification reactor to produce synthesis gas as well as to the hydrogasification reactor to produce char end product gas. The char is removed from the product gas and returned to the synthesis gas producing gasification reactor. Drying may be carried out utilizing a fluidized sand bed drying technique.

Energy Solution in China

Abstract: There is a way to considerably alleviate the real energy crisis--while at the same time protecting the environment, increasing crop yields, improving sanitation, and easing household work: biogas generation, a simple technology, appropriate for the developing nations. It utilizes organic wastes to produce, through anaerobic fermentation, a stable, nonpoisonous fuel of medium heat value (typically a mixture of 70% methane, 30% carbon dioxide, and traces of hydrogen, nitrogen, and hydrogen sulfide; caloric value is between 5,300 and 6,300 kilocalories per cubic meter, depending upon a number of factors) which can be used for cooking and lighting as well as for fueling farm machinery and for power generation. (Natural gas, used in gas ranges, has a heat value of 7,180 kilocalories per cubic meter.) Although the People's Republic of China is now self-sufficient in crude oil and ranks third in the world as a coal producer, commercial energy is not available readily or cheaply in many parts of the country, which still has inadequate transportation and a densely populated countryside. Recent large-scale adoption of biogas generation in China shows how much could be accomplished on a worldwide basis with a relatively simple and efficient technology utilizing abundant and, what is mostmore » important, renewable local resources. The design of a successful water-pressurized tank consisting of loading, fermentation, and sludge chambers is described. The benefits of biogas utilization are summarized. (MCW)« less

A cost-benefit analysis of biogas production in rural india: some policy issues

Abstract: The cost of an anaerobic digester (biogas plant) in rural India appears to exceed the benefit of the biogas produced, measured in terms of the value of the coal or electricity needed to do an equivalent amount of cooking. However, biogas plants are net producers of energy, which means that they can reduce the drain on India's foreign exchange from imports of petroleum. Additional secondary benefits from biogas plants are discussed that might justify public subsidization to encourage their adoption despite the unfavorable cost-benefit ratio.

Thermophilic MethaneProduction fromCattle Waste

Abstract: intensive animal production systems (3, 9).This has created significant waste disposalproblems alongwith problemsofstreampollu-tion and odor control (16). Anaerobic bacterialconversion ofthis waste with methaneproduc-tion mayoffer a partial solution to these prob-lemsandalsoservetosupplementthesupplyofnatural gas. In an economic analysis ofmeth-ane production from municipal solid waste in-volving mesophilic anaerobic microbial diges-tion, Kispert et al. (12) found that the cost ofproducing methane is economically acceptablewhencompared with projected costs ofnaturalgas. Studies of Pfeffer (17) showed that meth-ane production from municipal organic refusemaybe economical if carried out at

Energy Consumption in Rural Households and Biogas Plants: Tasks Ahead

Abstract: The recent upswing in the price of crude oil has prompted many nations to look into other sources of energy. The large number of cattle in this country makes it possible to consider biogas plants as an alternate energy source. The Fuel Policy Committee has recommended the popularization of biogas plants in rural areas. In this paper, the authors have analysed policy options and problems faced by various agencies in the promotion, sales, and servicing of biogas plants. Primary data were collected by interviewing a selected sample of plant owners in Gujarat State. Discussions were also held with officials of the Gujarat Rajya Khadi Gramodyog Board and the Khadi Village Industries Commission, two of the agencies involved in the promotional work. After a detailed analysis of the data, the authors have recommended certain measures to improve sales and servicing facilities and to optimize returns.

China claims lead in biogas energy supply

Abstract: China's large peasant population is contributing animal manure and vegetable wastes for biogas generating plants in the densely populated rural areas. Biogas, combining a simple and efficient technology and renewable local resources, represents a feasible source of power which developing countries could emulate without rejecting the concept for political reasons. The People's Republic of China, although self-sufficient in oil and coal, adopted large-scale biogas generation as a goal in 1958. A review of China's progress emphasizes the use of local materials and local distribution from over four million digesters. Household cooking and lighting are the primary uses. The Chinese have acquired knowledge and expertise in digester design, stressing the importance of carbon/nitrogen proportions and maintaining the proper liquidity and pH in the digester. The advantages claimed for anerobic fermentation include savings in fossil fuels, labor, fuel wood and grass, and money, as well as improved hygiene, local power generation, and a general raising of the rural standard of living. (DCK)

Engineering, operation and economics of biodigestion

Abstract: The paper describes the necessary process steps in the production of biogas. The most important technical components and the various types of operation in digestion are presented. Consideration is also given to the technically possible gas yield from the organic substance, and to the possible tank loading of the digesters. The overall economic significance of energy production by means of anaerobic decomposition of the organic sludges will be shown in the light of an energy balance for the Federal Republic of Germany. Subsequently, detailed cost estimates of American investigations are briefly compared to those from Germany. The technical requirements on biomass produced for the purpose of a microbial energy conversion are described. Finally, necessary improvements in the digestion technique are mentioned.