摘要:
In the mesophile production of biogas, the temperature of the liquid used during anaerobic, methanogenic, fermentation is raised to the required temperature (about 35.degree. 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.
摘要:
A reactor for the anaerobic digestion of organic sludge and for the production of methane gas, comprises an essentially horizontal cylindrical vessel provided with an agitator rotating around an essentially horizontal shaft, an inlet for introducing the sludge to be digested at one end of said vessel, at its opposite end an outlet for removing the digested matter from the vessel and in the upper portion of the vessel an outlet/outlets for the recovery of methane gas. For returning the solids settled on the bottom of the vessel from the outlet end of the vessel to the inlet end of the vessel, the vessel comprises a channel connecting the outlet end of the vessel with the inlet end of the vessel and a device for guiding the solids to the front of the return channel and for their transport through the return channel by means of gas.
摘要:
Non-organic substances are separated from household garbage and the organic substances are fed in proportioned manner into a mixing tank (5) and converted into slurry by adding liquid. The slurry is crushed for homogenization purposes in a crushing means (10, 11) and passed into a closed holding container (13). It is then fed over a heat exchanger (15) and heated to 55.degree. to 60.degree. C. The slurry passes into a plurality of reaction vessels (16) in which the methane gas and carbon dioxide are produced. In a separating plant (22), the mixture of gaseous products is broken down into its components and some of the methane gas is recycled by bubbling it through both the holding tank and the reaction tank, the remainder being stored in gasholders (23). The organic substances are degraded much more rapidly through increasing the degradation temperature and as a result constructional expenditure can be reduced.
摘要:
The present invention relates to an anaerobic digestion process for organic wastes with a high efficiency and an improved recovery rate of methane.This process comprises the following steps: (1) anaerobically digesting organic wastes under simultaneous presence of facultative anaerobic bacteria and obligatory anaerobic bacteria, (2) separating the anaerobically digested slurry obtained from the step (1) into a liquor fraction containing the two groups of bacteria and an undecomposed solid fraction, (3) mixing the liquor fraction obtained from the step (2) with the surplus activated sludge slurry produced by anaerobically treating organic waste water, under anaerobic condition, (4) separating the mixed slurry obtained from the step (3) into a solid fraction containing the surplus activated sludge which has absorbed the two groups of bacteria and a liquor fraction, and recycling back the solid fraction obtained from the step (4) as the sources of the two groups of bacteria and nitrogen to the step (1).
摘要:
Described is a process for screening of microorganisms for the production of amylolytic enzymes. Microorganisms capable of amylolytic enzyme synthesis and growing on the surface of a solid medium are detected by identifying a zone of hydrolyzed starch surrounding each microorganism. The process is particularly useful for the detection of .alpha.-amylase activity in strains of Bacillus licheniformis as it employs a selection step under anaerobic conditions prior to the detection of the enzyme.
摘要:
Ethanol (C.sub.2 H.sub.5 OH) is produced efficiently by employing a drive-through pit in which carbohydrate-containing material is fermented by hydrolyzing agents such as enzymes. The configuration and depth of the pit are such as to permit conventional farm vehicles to have ready access to the pit, thereby enabling the pit to be loaded and unloaded conveniently. The pit is insulated on its sides and bottom and is closed at the top by a heat-insulating cover. The pit is heated to assist the fermentation process. After several days of heating, the pit is drained through a sediment trap and the filtered pit drainage is separated into concentrated ethanol and a mixture of water and enzymes. The solid residue left in the pit is removed for use as feed or fertilizer. The separated water and hydrolyzing agents are stored in a reservoir for subsequent flooding of the pit when a new quantity of carbohydrate-containing material is added to the pit.
摘要:
Derivatives of the newly discovered microorganism Thermoanaerobacter ethanolicus which under anaerobic and thermophilic conditions continuously ferment substrates such as starch, cellobiose, glucose, xylose and other sugars to produce recoverable amounts of ethanol solving the problem of fermentations yielding low concentrations of ethanol using the parent strain of the microorganism Thermoanaerobacter ethanolicus are disclosed. These new derivatives are ethanol tolerant up to 10% (v/v) ethanol during fermentation. The process includes the use of an aqueous fermentation medium, containing the substrate at a substrate concentration greater than 1% (w/v).
摘要:
A device for culturing microorganisms includes a vessel having a mouth for containing a culture medium and a stopper member for hermetically sealing the vessel. The stopper member is provided with a through hole on its peripheral wall for communicating with the inner atmosphere of said vessel.
摘要:
A process for improved methane production resulting in higher yield and higher production rates by anaerobic digestion of a mixture of plant material and organic waste. The process is suitable for production of synthetic natural gas and through anaerobic digestion of a mixture of plant material and organic waste allows better matching of organic waste and plant material feed supplies for year round operation. The process of this invention results in digester effluent which is easily dewatered and has a low concentration of soluble organics, providing easy disposal and recycling to the digester. The process of this invention may be used for methane production from plant material which is, by itself, recalcitrant to anaerobic digestion.
摘要:
Safety catalyst systems and their use in chemical reactions carried out in the gas phase, wherein the safety catalyst system comprises pelleted catalyst held loose in and throughout the holes and folds of a folded or rolled up metal foil net which is inside a container having holes for the inflow and outflow of gases. The safety catalyst system of the invention does not allow the formation of localized hot-spots or allow free catalyst dust to escape from the system, both of which are known disadvantages of prior art systems.