The composite acidifier of superphosphate and sulfuric acid for swine slurry storage treatment: Assessment of gases emission reduction and stabilization

Abstract

To realize ammonia emission reduction, greenhouse gas emission reduction and stabilized treatment during manure slurry storage, a novel composite acidifier was proposed in this study. The composite acidifier was composed of superphosphate and sulfuric acid (SP-SA) at different proportions, and the performance of gas emission reduction and stabilization was also conducted. The composite SP-SA acidification could reduce 46.79% – 72.71% of ammonia emission and 38.95% – 69.21% of greenhouse gas emission. Due to the slow release of H⁺, groups with more superphosphate addition could reduce 5.68% – 10.71% of ammonia emission and 17.35% – 20.83% of greenhouse gas emission. All acidified groups could achieve total nitrogen loss ranged from 29.40% to 38.59%, attributed to the ammonia emission reduction. Compared to control group, a maximum removal rate of 35.05% for chemical oxygen demand and 40.63% for dissolved organic carbon could be obtained for the acidified group. The acidified group could reach stabilization on 20th d, which was 20 d earlier than control group. The composite SP-SA acidifier could be a candidate to swine manure slurry storage treatment, which possessed advantages of low pH maintaining, gases emission mitigation and fast stabilization.