초록 ▼

The present invention relates to a process for digestion treatment of organic wastes that are difficult to digest, with a high efficiency and an improved recovery rate of methane. The wastes, before subjected to anaerobic treatment, are heated at 55°-75°C. within an acid or alkaline solution for dis

The present invention relates to a process for digestion treatment of organic wastes that are difficult to digest, with a high efficiency and an improved recovery rate of methane. The wastes, before subjected to anaerobic treatment, are heated at 55°-75°C. within an acid or alkaline solution for dissolving digestible ingredients and the insoluble ingredients are eliminated before being transferred to an anaerobic digestion step. By exercising a pre-treatment for dissolving and separating digestible ingredients, the size of the container will be minimized as a result of the shortened time required for digestion and the recovery rate of methane will be improved.

대표청구항 ▼

An anaerobic digestion process comprising the following steps: (1) Heating and stirring a mixture of crushed organic waste and the waste water obtained in step (9) at a temperature of 55°-75°C., while maintaining the pH of said mixture at 2.5-4.0 for making a slurry from said mixture, (2) Obtaining

An anaerobic digestion process comprising the following steps: (1) Heating and stirring a mixture of crushed organic waste and the waste water obtained in step (9) at a temperature of 55°-75°C., while maintaining the pH of said mixture at 2.5-4.0 for making a slurry from said mixture, (2) Obtaining a separated liquid portion and a residue from the slurry recovered from the first step by solid/liquid separation, (3) Anaerobically digesting the separated liquid portion recovered from the second step under neutral to slightly alkaline conditions by introducing liquefaction and gasification bacteria to said liquid portion, (4) Obtaining separated water by removing digestive sludge from the slurry obtained from the third step by solid/liquid separation, (5) Aerobically treating the separated water obtained from step (4), (6) Obtaining an effluent by solid/liquid separation from the liquid aerobically treated in step (5), (7) Mixing together a part of the separated water obtained from step (6) with the residue obtained from the step (2), (8) Obtaining washed residue and waste wash water from the mixture at the seventh step by solid/liquid separation, and (9) Supplying said waste wash water obtained in step (8) to step (1). An anaerobic digestion process comprising the following steps: (1) Heating and stirring a mixture of crushed organic waste and the waste wash water obtained in step (9) at a temperature of 55°-75°C., while maintaining the pH of said mixture at 8.0-9.8 for making a slurry from said mixture, (2) Obtaining a separated liquid portion and a residue from the slurry recovered from the first step by solid/liquid separation, (3) Anaerobically digesting the separation liquid portion recovered from the second step under neutral to slightly alkaline conditions by introducing liquefaction and gasification bacteria to said liquid protion, (4) Obtaining separated water by removing digestive sludge from the slurry obtained from the third step by solid/liquid separation, (5) Aerobically treating the separated water obtained from step (4), (6) Obtaining an effluent by solid/liquid separation from the liquid aerobically treated in step (5), (7) Mixing together a part of the separated water obtained from step (6) with the residue obtained from the step (2), (8) Obtaining washed residue and waste wash water from the mixture at the seventh step by solid/liquid separation, and (9) Supplying said waste wash water obtained in step (8) to step (1).