Biogas genset methane bacteria working conditions and environment
Appropriate concentration of dry matter biogas genset methane bacteria not only to eat, to drink. Methane bacteria in the process of growth, development, reproduction, all need enough water. Water is an important part of methane bacteria, organic material in the biogas fermentation must have the right amount of moisture. If too little water content in the material liquid fermentation, the fermentation raw material too much, the concentration of the fermentation liquor is too large, methane bacteria and can't eat so many, is likely to cause a substantial accumulation of organic acids, is not conducive to methane bacteria breeding, fermentation will be hampered, and at the same time it brings difficulties to stir. If too much water, fermented liquid dilute, unit volume little, organic matter content in gas production rate, less conducive to make full use of the pool, so the biogas fermenting liquid must maintain a certain concentration of dry matter. According to many years practice, the rural household biogas digester is general requirement for fermentation raw material of dry matter content of 6% ~ 12%, and in this range, the biogas initial concentration is lower, and it is easy to start. High summer and early autumn ChiWen, raw materials decompose quickly, can lower concentration, general is 6% ~ 8%. Winter and early spring ChiWen low, raw materials decompose slowly, dry material concentration should be kept in 10% ~ 12%. The suitable temperature is one of the important conditions for production of biogas fermentation temperature, when the biogas fermentation temperature directly affect the digestion rate and gas rate of raw material, within the scope of the optimum temperature the higher the temperature, the faster growth, reproduction, methane bacteria produce gas. Temperature is not appropriate, methane bacteria growth slow, less gas or gas. Microorganism is sensitive to temperature changes at the same time, the temperature rose or fell sharply, will affect the life activities of microorganism, worsen gas condition. Biogas fermentation with wider range of temperature, average 8 ~ 60 ℃ can produce methane. Below 10 ℃ or above 60 ℃ were severely inhibit microbial survival, reproduction, affect the gas. People place the biogas fermentation is divided into three fermentation area, which is 10 ~ 26 ℃ to room temperature fermentation, 28 ~ 38 ℃ fermentation temperature in the area, to 46 ~ 60 ℃ high temperature fermentation area. Some industrial fermentation of organic waste water, waste, such as the winery eduction of vinasse, due to the discharge temperature is above 70 ℃, no needs to add heat to improve the external temperature, fermentation materials commonly used high temperature fermentation. Urban sludge, industrial organic wastewater, large and medium-sized livestock feces, etc, the appropriate use of temperature fermentation. Rural biogas fermentation, because of the limitation of conditions, generally USES the normal temperature fermentation, winter ChiWen low yield less gas or gas. In order to improve the pool temperature, in the northern cold region, more than the pool built in plastic greenhouse or solar livestock shed, increase ChiWen, improve gas production of winter, often producing gas. Continuous dynamic frequently stirred fermented liquid fermentation have close relationship with increasing gas production. Rural household biogas digester in static state, generally can be divided into three layers: the upper is scum layer, fermentation raw material is more, less methane bacteria, not make full use of raw material, if the scum is too thick, can also affect the gas into the gas tank. Middle is a clear liquid, water more, less fermentation raw material. Is the lower sediment, raw materials, fermentation strains of biogas is rich, is one of the important parts to produce biogas. Pool, therefore, often do not churn, had a great influence on biogas production. Some raw materials for biogas digester and very full, but the gas production is more and more small, one of the most important reason is the fermented liquid surface formed a thick crust. Appropriate pH pH value is the value of hydrogen ion concentration index commonly known as, acidic or alkaline degree of numerical solution. Biogas microbial growth, reproduction and asked for fermentation of raw material keep neutral or slightly alkaline ph ( The pH = 6. 5 to 7. 5) , acid and alkali will affect the gas. The test showed that pH between pH = 6 ~ 8, all can produce gas, with pH = 6. 8 to 7. 5 gas production rate is high, the pH value is lower than 4. 9 or higher than 9 are not gas. Pool early biogas fermentation, due to the activities of the bacteria produce acid to produce large amounts of organic acids, decreased pH value, as the fermentation to proceed, on the one hand, part of the ammonia neutralization of the organic acid ammoniation bacteria, methane bacteria use organic acids into methane on the other hand, pH value and return to normal, so the cycle continues keep pH within the pool at 7. 0 ~ 7. 5, within the scope of the normal fermentation. So pool inside the material liquid fermentation, just keep a certain moisture content, inoculum and appropriate temperature, it will be normal fermentation, does not need to adjust. Such as pool initial startup, feeding concentration is too high, the number of methanogens in inoculum and insufficient, or to the pool inside a lot of chicken manure, potato slag, cause fermentation material liquid concentration is too high, can be caused by the speed of the methane-producing disorders of volatile acid accumulation, resulting in a decline in pH, caused the biogas failed to start or run. At this point, reveal a part of the material liquid, by adding the same amount of new material liquid, dilute the volatile acid, or add the right amount of plant ash, lime clarified liquid ph adjustment.