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The basic principle of anaerobic storage using biogas is as follows: under sealed conditions, taking advantage of the high levels of methane and carbon dioxide, low oxygen content, and non-toxic nature of methane in biogas, the gas composition in the storage environment is adjusted to create a state of partial oxygen deficiency. This helps to control the respiration rate of grains, fruits, and vegetables, reducing material loss during storage and thereby achieving safe storage conditions. The equipment is covered with a layer of polyethylene plastic sheeting with a thickness of 0.1–0.2 millimeters over the grain silo, and the edges are sealed to the walls. At its top, a copper tube is installed as an exhaust channel, which is connected to an oxygen meter or carbon dioxide analyzer (used to measure the gas content or carbon dioxide level in the grain pile at any time). At the bottom of the grain pile, a radial air intake diffuser is placed, which is connected to a biogas flow meter. After the operation and control equipment has been installed and checked for any leaks or blockages, the biogas supply valve can be opened to allow biogas to enter the grain pile. Driven by the pressure of biogas, the gas inside the grain pile is expelled from the exhaust pipe at the top of the silo, passing through measuring instruments before being released outside. When the amount of gas introduced reaches 1.5 times the volume of the grain pile, and the oxygen content drops to 1%–5% while the carbon dioxide content rises to 20%–30%, the exhaust pipe and the biogas switch are turned off, and the silo is sealed for 3–5 days. This process kills the main pests that infest grains, such as corn weevils and mung bean weevils, and the pest-free period can last for about a year. Precautions: Plastic tents and pipeline systems must be tightly sealed; open flames or smoking are strictly prohibited in the warehouse. The grain stored there should be dry, and the biogas supplied must first be dehydrated, with regular ventilation being necessary.