Abstract: Key processes of whole energy and substance recycling for large-scale biogas project includes collection and pretreatment of raw materials, anaerobic digestion, aerobic water disposal, purging, deposition and transportation of biogas, innoxious treatment of residue fluid and sludge, and crop application. Raw material configuration follows certain conditions after processing and purging. Then they are put into digestion tanks for biogas production under appropriate fermentation condition. Water and hydrogen sulfide (H₂S) must be removed from the gas. Water is usually removed by installment of dehydrates and H₂S is removed by desulfate temple filled with desulfurizer. The residue fluid and sludge can promote crop growth, improve crop quality and increase crop resistance to disease and pests.