Aqueous and solid ammonium sulfate fertilizers and methods of producing

Abstract

Aqueous and solid ammonium sulfate fertilizers derived from an organic feedstock and a mineral sulfate compound. The aqueous fertilizers have at least 3.5% nitrogen and at least 4% sulfur, and the solid fertilizers have about 21% nitrogen and about 24% sulfur. Methods for producing the fertilizers include preparing an organic feedstock by causing organic waste to undergo anaerobic digestion, removing solids from the organic feedstock to produce an organic liquid effluent, performing a distillation process on the organic liquid effluent to strip and concentrate a vapor that contains ammonia, carbon dioxide, and water and cool the vapor to produce a condensed solution containing ammonium bicarbonate and/or ammonium carbonate, and contacting the condensed solution with the mineral sulfate compound to cause a reaction therebetween and produce an aqueous ammonium sulfate product. An evaporation process can be performed on the aqueous ammonium sulfate product to produce a dry, solid ammonium sulfate product.

Dependencies are inferred from the claim text.