Showing papers on "Biogas published in 1986"
TL;DR: In this paper, a two-stage process is developed, in which the propionate degradation is spatially separated from other conversions in which hydrogen is involved, and significantly better results were obtained with the two stage system as compared with a one-stage system with an equal total volume.
87 citations
TL;DR: The concentration of hydrogen in the biogas was monitored and was shown to have the potential of being a sensitive and rapid indicator of perturbation within the digester.
Abstract: A 6m3 pilot scale anaerobic contact digester treating brewery effluent was subjected to volumetric shock loadings. The concentration of hydrogen in the biogas was monitored and was shown to have the potential of being a sensitive and rapid indicator of perturbation within the digester.
74 citations
Book•
01 Jan 1986
TL;DR: The history, technology, and applications of anaerobic digestion, the biological process by which organic materials are degraded in the absence of oxygen to produce a combustible gas, methane, and carbon dioxide, are explored in this article.
Abstract: This report, one in a continuing subseries on ''integrated resource recovery,'' explores the history, technology, and applications of anaerobic digestion, the biological process by which organic materials are degraded in the absence of oxygen to produce a combustible gas, methane, and carbon dioxide.
53 citations
TL;DR: In this paper, anaerobic digestion of rice crop residues-husk and straw-was carried out in 190-litre metallic digesters, and a mixture of rice straw and cattle dung (1:1 dry weight basis) yielded 9·1% more gas than rice straw alone.
44 citations
TL;DR: In this paper, the authors present the present state of municipal solid waste disposal in Brazil, focusing on the particular situation in the City of Sao Paulo, and indicate the future trend of the anaerobic digestion approach for this residue.
40 citations
TL;DR: In this article, a new design of a collection-cum-storage water heater integrated with the dome of conventional Indian (KVIC) biogas units has been proposed and studied theoretically.
37 citations
TL;DR: Long-term fermentations of N-rich crops gave high methane yields and productivities at steady-state conditions without enrichment of chemical substances, and Acetogenic and methanogenic populations were higher in digester fed silages of lower C : N ratio.
36 citations
TL;DR: In this paper, an experimental study was undertaken to determine the effects of administering shock loads of sucrose to a laboratory-scale anaerobic effluent treatment plant (UASB reactor) treating diluted landfill leachate.
35 citations
31 citations
TL;DR: An integrated system for the bioconversion of poultry droppings for biogas production and utilization of the effluent for the production of the blue-green alga Spirulina platensis was studied and appears promising.
TL;DR: Use of an antibiotic-resistant strain of Salmonella typhimurium as a test organism to study its survival during anaerobic digestion showed that the organism is totally eliminated in nine days.
Abstract: Anaerobic digestion of night soil with cattle dung slurry in biogas plants is advocated in Indian villages as a means of disposal of human excreta in the absence of conventional sanitary systems. Although intestinal pathogens are likely to be eliminated during anaerobic digestion, there is no conclusive evidence that this is so. Large numbers of saprophytic organisms in the fermenting mass make it impossible to detect the residual pathogens. Use of an antibiotic-resistant strain of Salmonella typhimurium as a test organism to study its survival during anaerobic digestion showed that the organism is totally eliminated in nine days.
30 Apr 1986
TL;DR: A survey of existing systems and descriptions of various models in current use, as well as a detailed exploration of the technical aspects of anaerobic digestion in both the text and appendix is provided in this paper.
Abstract: This report summarizes the current and potential status and practice of anaerobic digestion in developing countries and provides an overview of the subject, plus practical data for building an anaerobic digester. Relevant information includes a survey of existing systems and descriptions of various models in current use, as well as a detailed exploration of the technical aspects of anaerobic digestion in both the text and appendix. Emphasis is on applying new engineering concepts to low-cost technologies, on energy, and on environmental and agricultural benefits. Energy and health benefits from digestion of night soil, septage, and sludges can be achieved by properly engineered and operated biogas technologies.
TL;DR: In this article, the concept of palm oil mill effluent treatment has changed, and there have been several research and development projects to investigate the utilization of the so called waste materials from the palm oil mills.
TL;DR: In this paper, experiments were conducted with pilot small-scale biogas digesters designed for the family level in developing countries, where four 3.5 m 3 ferrocement digesters equipped with manually operated mixers were fed a mixture of nightsoil, water hyacinth ( Eichhornia crassipes ) and rice straw and operated semi-continuously at hydraulic retention times (HRT) of 30, 50 and 70 days, corresponding to organic loadings of 1.2, 0.75 and 0.53 kg m −3 day −
Patent•
19 Mar 1986TL;DR: In this paper, a biogas stream is filtered to remove solid particulate matter therefrom and is then charged as fuel to the electric power producing combustion turbine for the production of electric power.
Abstract: Electric power is produced in an electric power generating combustion turbine using a biogas as fuel thereto, where a biogas, leaving a biomass gasification system at an elevated temperature of 650°-875° C. and containing tars, is partially cooled by injection of a spray of water thereto to a lower temperature of about 260°-555° but above that which would condense tars. The partially cooled biogas stream is then filtered to remove solid particulate matter therefrom and is directly charged as fuel to the electric power producing combustion turbine for the production of electric power.
TL;DR: In this article, two identical continuously stirred tank reactors (CSTR) of 125 m3 capacity were used to digest anaerobically dairy cow slurry of about 7% total solids (TS).
Patent•
10 Mar 1986
TL;DR: In this paper, the photosynthetic properties of microorganisms are exploited to fix carbon dioxide, SO2 and NOx in biological compounds with the aid of light energy and metal ions can be accumulated simultaneously.
Abstract: The urgently necessary decrease of carbon dioxide emission, which is formed in large amounts in the oxidation of fossil fuels, has previously appeared to be scarcely possible. The energy to be employed in physicochemical processes to decrease the emission is considerable (approximately 40 % of the combustion energy) and finally had to be repaid by carbon dioxide emission (1). The process presented here utilises the photosynthetic properties of microorganisms which can tolerate extreme pollutant loads to fix carbon dioxide, SO2 and NOx in biological compounds with the aid of light energy. Metal ions can be accumulated simultaneously. The process provides the uncomplicated direct introduction of exhaust gas/exhaust air into the illuminated culture. When sunlight is used, the process appears extremely favourably in the energy balance, since the pollutants are biologically converted into energy-rich compounds which can be utilised in turn (e.g. biogas).
TL;DR: Some methods of increasing biogas production from agricultural wastes were tested in this paper, which showed that adding inert but surface-active materials (glass marbles, plastic mesh and stone pebbles) to a cattle-dung digestion yielded 15% to 30% more gas than more gas control in batch digestions.
TL;DR: The anaerobic rotating biological contact reactor performed better than the fixed- film reactor on methane production and can maintain a constant active volume which is not possible in a fixed-film reactor.
TL;DR: The results indicate that H2S could be selectively and completely removed from the biogas until the silica gel became saturated, and the color ofsilica gel changed from blue to black.
Abstract: The removal of hydrogen sulfide from biogas by silica gel was systematically studied The results indicate that H(2)S could be selectively and completely removed from the biogas until the silica gel became saturated When it became saturated, the color of silica gel changed from blue to black The used silica gel could easily be regenerated and reused The factors that affected the purification of biogas by silica gel were found to be the flow rate of biogas, the regeneration temperature, the degree of saturation of the silica gel, and the water content of silica gel A mathematical model describing the operation of the adsorber was developed The breakthrough curves and mass transfer coefficients of H(2)S were also obtained
TL;DR: The effects of various wastes with castor cake in relation to biogas generation and digester microbiological activities were determined in this paper, where the physicico-chemical properties of cowdung, castor cakes, maize cob (grain removed), mixed vegetable wastes and weed samples and their proportion of mixing were characterised.
Patent•
05 Feb 1986
TL;DR: In this article, the authors describe a process for the preparation of liquid manure from cattle excrement, if appropriate after fermentation resulting in the production of methane, the liquid manure first being alkalinised with lime, before the separation of the sludge obtained and the conveyance of the residual water at the head of a rectifying column.
Abstract: Process for the preparation of liquid manure from cattle excrement, if appropriate after fermentation resulting in the production of methane, the liquid manure first being alkalinised with lime, before the separation of the sludge obtained and the conveyance of the residual water at the head of a rectifying column, in which the ammonia is driven off by steam, of which the condensation with the ammonia gives ammonia water, in which the ammonia is fixed to carbon dioxide to give ammonium carbonate as a result of the contact of the ammonia water with the biogas or with the fumes obtained as a result of the combustion of the biogas, the residual water being sterilised during the extraction of the ammonia.
TL;DR: The results demonstrated that a combination of anaerobic and aerobic treatment produced a very high degree of purification and substantial amounts of methane gas.
TL;DR: In this article, the anaerobic digestion of stillage from a pilot-scale wood-to-ethanol process was investigated using an 8-litre, continuously-fed reactor.
Abstract: The anaerobic digestion of stillage from a pilot‐scale wood‐to‐ethanol process was investigated using an 8‐litre, continuously‐fed reactor. A methanogenic consortium acclimated to Pinus radiata stillage was developed over 160 days by maintaining a low organic loading rate. The loading rate was then gradually increased to c. 4 kg COD m‐3 day‐1. Nutrient, alkalinity, and mineral requirements were quantified. Approximately 90% COD removal was obtained at specific COD utilisation rates up to 0.5 g COD g VSS ‐1 day‐1. The methane and true cell yields, per gram of soluble COD removed, were 0.313 1 CH4(STP) and 0.142 g VSS. The endogenous decay coefficient was 0.0083 day‐1.
TL;DR: A telephone survey of 75 landfill gas facilities in the U.S.A. was carried out at the end of 1983 as discussed by the authors, which showed that more than half of existing sites upgraded the heat content of the gas and two thirds of the plans for new facilities call for direct use of low heat content gas, primarily to generate electricity.
TL;DR: A multistage aquacultural system based on methanogenic bacteria, photosynthetic bacteria, microalgae, and floating macrophytes was developed to produce methane, protein supplements, and fibrous feeds from swine wastes under subtropical climatic conditions in the southeastern United States.
Patent•
26 Mar 1986
TL;DR: In the mesophile production of biogas, the temperature of the liquid used during anaerobic, methanogenic, fermentation is raised to the required temperature (about 35 DEG C) by aerobically prefermenting solid substrate at substantially ambient temperature and of appropriate moisture content to raise its temperature to a temperature greater than that required for the Anaerobic Methanogenic fermentation as discussed by the authors.
Abstract: In the mesophile production of biogas, the temperature of the liquid used during anaerobic, methanogenic, fermentation is raised to the required temperature (about 35 DEG C.) by aerobically prefermenting solid substrate at substantially ambient temperature and of appropriate moisture content to raise its temperature to a temperature greater than that required for the anaerobic, methanogenic, fermentation. Thereafter flooding the fermenting solid substrate with the liquid at substantially ambient temperature to increase the temperature of the liquid by heat exchange, and then removing the liquid and storing it in a heat insulated environment to reduce the moisture content of the solid substrate to a suitable degree. The above steps of aerobic prefermenting and flooding are repeated until the liquid has reached the required temperature, and then leaving the liquid in situ to enable anaerobic methanogenic fermentation to take place. In so doing the supply of external heat for the initial warming up of the substrate may be dispensed with, thereby improving the efficiency of the method.