Production method of biological carbon coated controlled-release fertilizer

The invention discloses a production method of a biological carbon coated controlled-release fertilizer and belongs to the technical field of recycling of agricultural waste and soil fertilizer. The production method comprises the following steps: crushing dry biomass material, performing pyrolysis for 0.5-12 hours under an anaerobic condition at 250-800 DEG C to form biological carbon granules, and cooling and grinding to obtain biological carbon powder with the particle size of 74-180 microns; screening granular fertilizer, transferring the screened granular fertilizer into a blast fluidized bed, preheating, and then spraying a binding agent to ensure that the surface of the continuously rolling granular fertilizer is coated with the binding agent and a uniform liquid layer is formed gradually; and spraying the biological carbon powder to the continuously rolling granular fertilizer, continuously heating to keep the material temperature at 60-70 DEG C, treating for 10-15 minutes so that the moving granular fertilizer is coated with the biological carbon powder and a coating layer is formed after curing, coating the fertilizer for 2-5 times, uniformly mixing, and then performing air drying or pelleting by virtue of a pelleting machine or performing compression mold forming. The controlled-release fertilizer obtained by the method disclosed by the invention is degradable and has a good controlled release effect.