METHOD FOR MANUFACTURING METHANE FROM ORGANIC WASTE

PROBLEM TO BE SOLVED: To provide a method for manufacturing methane using an inexpensive facility where processing costs are reduced by producing methane gas simultaneously with efficient processing of organic waste.SOLUTION: There is provided a method that in a process of producing methane from hydrolysis water applying a subcritical reaction includes: disposing an acid fermentation tank 12 for producing organic acid and the like from hydrolysis water by using acid-forming bacteria, and a methane fermentation tank 22 for methane-fermenting an acid fermentation liquid from the acid fermentation tank 12; and arranging a lock material 25 of fine mesh made of high-polarity resin, as a bacteria adsorbent, inside the acid fermentation tank 12 and the methane fermentation tank 22 to form a high-density environment of the acid-forming bacteria and methanogens and create a highly efficient environment. In the acid fermentation tank, acid-forming bacteria are continuously added to the hydrolysis water while adjusting an amount so that production of organic acid is compensated, whereas in the methane fermentation tank 22, a coexistence and symbiosis environment of facultative bacteria and methanogens is constructed so that methane is efficiently produced while at the same time avoiding methane fermentation obstruction accompanying accumulation of propionic acid and the like.SELECTED DRAWING: Figure 1 【課題】有機生ゴミを効率的に処理すると同時にメタンガスを生成することにより、処理コストを削減した、安価な設備によるメタン製造方法の提供。【解決手段】亜臨界反応による加水分解水からメタンを生成する過程において、加水分解水から、酸生成菌により有機酸等を生成する酸発酵槽１２と、酸発酵槽１２からの酸発酵液をメタン発酵するメタン発酵槽２２とを設け、酸発酵槽１２とメタン発酵槽２２とに、高い極性を持つ樹脂からつくられたメッシュの細かなロック材２５を菌の吸着材として内部に配設して、酸生成菌およびメタン菌の高密度環境を形成し、高効率環境を作る。酸発酵槽では有機酸の生成を補償するように量を調節しながら酸生成菌を加水分解水に連続的に加え、メタン発酵槽２２では通性菌とメタン菌との共存・共生環境を構築して、プロピオン酸等の蓄積に伴なうメタン発酵阻害を避けると同時に効率的なメタン生成を可能にする方法。【選択図】図１