The distribution and change of temperature field will directly affect the gas production rate and gas production rate of the whole system. Biogas fermentation is greatly affected by temperature. In summer and autumn, the temperature of natural gas production, especially in winter, is low. The temperature of biogas fermentation raw materials is usually lower than 10 ℃. Biogas production is seriously affected. In order to meet the demand of natural gas supply throughout the year, it is necessary to strengthen the heat preservation work in winter and spring. The main measures are as follows:
(1) Add warm feces
加入人粪肥、马粪或堆肥后的新鲜干草等发热量原料，适当提高池液浓度至10 ~ 12%;
Add the raw materials of calorific value such as human manure, horse manure or fresh hay after composting, and properly increase the concentration of the tank liquid to 10 ~ 12%;
(2) Increase wind barrier and reduce temperature consumption
The biogas digester is built on the leeward or the northwest wall of the digester, which is also a simple method to reduce the temperature consumption;
(3) Straw covering and heat preservation
Covering ponds with crop straws or hay can also reduce temperature loss.
(4) Covered plastic greenhouse
&The biogas digester can be built on the plastic shed of animal circle, which is not only conducive to the winter heat preservation of livestock and poultry, but also conducive to the liquid temperature of the materials in the digester, and is the best measure for the winter and spring heat preservation of biogas digester.
(5) Increase liquid temperature
If possible, it is best to match with solar water heater, and use warm water to wash manure and feed it to the pond;
(6) Trenching to prevent cold
If conditions permit, a 50 cm wide trench deeper than frozen soil can be dug around the biogas digester to fill with manure and grass insulation materials, which can play a role in maintaining the temperature in the digester.