沼氣,顧名思義,就是沼氣,是有機物在厭氧條件下的混合物,通過微生物發(fā)酵而形成的一種混合物氣體。我們經(jīng)常看到,在沼澤里,在下水道里,或在糞池里,都有氣泡冒出來,如果我們劃一根火柴,就能把它點燃。這是天然生成的甲烷。由于這種氣體初是在沼澤中發(fā)現(xiàn)的,所以被稱為甲烷。人畜糞便、秸稈、污水等有機物在密閉的沼氣池中,在厭氧(無氧)條件下發(fā)酵,從而產(chǎn)生沼氣。沼氣是一種可以燃燒的混合氣體。沼氣是微生物對有機物進行厭氧消化產(chǎn)生的可燃氣體。沼氣是多種氣體的混合物,通常含有50%到70%的甲烷,其余是二氧化碳和少量的氮氣、氫氣和硫化氫。它的性質(zhì)與天然氣相似。
Biogas, as the name implies, is a mixture of organic substances under anaerobic conditions, which is formed by microbial fermentation. We often see bubbles coming out in swamps, sewers or cesspools. If we strike a match, we can light it. It's natural methane. Since this gas was first found in swamps, it is called methane. Biogas is produced by anaerobic (anaerobic) fermentation of human and animal manure, straw, sewage and other organic matters in a closed biogas digester. Biogas is a combustible mixture. Biogas is a combustible gas produced by anaerobic digestion of organic matter by microorganisms. Biogas is a mixture of many gases, usually containing 50% to 70% methane, the rest is carbon dioxide and a small amount of nitrogen, hydrogen and hydrogen sulfide. Its nature is similar to that of natural gas.
沼氣是有機物在隔離空氣和保持一定濕度、溫度、ph等條件下,經(jīng)過多種微生物(統(tǒng)稱沼氣細菌)分解而產(chǎn)生的。細菌分解有機物產(chǎn)生沼氣的過程叫做沼氣發(fā)酵。這是產(chǎn)甲烷的基本原理,即厭氧機理,人工產(chǎn)甲烷必須具備兩個條件:,必須有嚴格的厭氧環(huán)境;二是發(fā)酵原料充足,菌劑充足,發(fā)酵濃度、發(fā)酵溫度、ph值適宜。發(fā)酵的生化過程可分為三個階段:
Biogas is produced by the decomposition of a variety of microorganisms (collectively referred to as biogas bacteria) under the conditions of air isolation and maintaining a certain humidity, temperature, pH, etc. The process of biogas production by bacteria is called biogas fermentation. This is the basic principle of methanogenesis, i.e. anaerobic mechanism. Artificial methanogenesis must have two conditions: first, there must be a strict anaerobic environment; second, there must be sufficient fermentation raw materials, sufficient bacterial agents, and appropriate fermentation concentration, fermentation temperature and pH value. The biochemical process of fermentation can be divided into three stages:
階段1(液化階段):可發(fā)酵細菌使用由細菌分泌的胞外酶分解等大型分子有機物家禽糞便、作物秸稈和廢水處理的大豆產(chǎn)品成小分子化合物如單糖、氨基酸、甘油和脂肪酸,溶于水。
Stage 1 (liquefying stage): fermentable bacteria use large molecular organics such as extracellular enzymes secreted by bacteria to decompose poultry manure, crop straw and soybean products for wastewater treatment to form small molecular compounds such as monosaccharide, amino acid, glycerin and fatty acid, which are soluble in water.
第二階段(制酸階段):發(fā)酵菌將小分子化合物分解成乙酸、丙酸、丁酸、氫和二氧化碳等,再轉(zhuǎn)化成乙酸、氫和二氧化碳,供產(chǎn)甲烷菌利用。
The second stage (acid making stage): fermentation bacteria decompose small molecular compounds into acetic acid, propionic acid, butyric acid, hydrogen and carbon dioxide, and then convert them into acetic acid, hydrogen and carbon dioxide for methanogens to use.
第三階段(產(chǎn)甲烷階段):產(chǎn)甲烷菌菌落,利用上述三種產(chǎn)甲烷菌分解轉(zhuǎn)化甲酸、乙酸、氫和二氧化碳小分子化合物產(chǎn)生甲烷。沼氣發(fā)酵的三個階段相互依存、連續(xù)不斷,保持著動態(tài)平衡。在沼氣發(fā)酵的初始階段,和第二階段起主要作用,同時也是第三階段的作用。在沼氣發(fā)酵的后期,三個階段的作用是同時進行的,經(jīng)過一定的時間,保持一定的動態(tài)平衡,繼續(xù)正常的產(chǎn)氣。
The third stage (methanogenic stage): methanogenic bacteria colony, using the above three methanogenic bacteria to decompose and transform formic acid, acetic acid, hydrogen and carbon dioxide small molecular compounds to produce methane. The three stages of biogas fermentation are interdependent and continuous, maintaining a dynamic balance. In the initial stage of biogas fermentation, the first and second stages play the main role, but also the third stage. In the later stage of biogas fermentation, the three stages are carried out at the same time. After a certain period of time, maintain a certain dynamic balance and continue to produce gas normally.