To solve the problem of low gas production rate and low utilization rate in northern regions in winter.A 3D thermal control model based on the theory of percolation is established.In this model

the marsh gas tank and the surrounding soil are seen as an organic whole

it makes the broth thermostatic by analyzing and controlling the soil temperature around the marsh gas tank.A solar energy marsh gas tank control system is designed

using solar energy heat-collecting system to heat the liquid material

and automatically control the temperature of the liquid material fluctuating in the range of ± 2 ℃.It simulates with Proteus and Matlab to verify the correctness of control model and system.