Digestate containing 10% --20% of the humic acids, humic acid substances generated bicarbonate solution or aqueous ammonia humic acids in the molecular structure an acidic group, may increase the mass of active humic acid, and improve efficiency .

The method of retting humic acid fertilizer is methane, the retting extracted with biogas digester and organic rubbish or soil layer of waste (or mud) plus one 20-- biogas 30 cm thick stack shaped into a compost heap table great circle, and then cover the surface of the earth and these tapped, retting 15--20 days Serve biogas rot fertilizer. If retting biogas per cubic meter of calcium, magnesium, phosphate, or phosphate rock 20--25 kg into the marsh rot phosphate. The fertilizer is suitable for use as a base fertilizer, and the application amount per acre is 1000 kg.

According to the Beijing Agricultural College Division test, marsh rot fertilizer to increase yield of wheat, corn, eggplant, peppers and other significant corn may yield 13.8%, green pepper yield of 15%.