Effects of phosphogypsum and superphosphate on compost maturity and gaseous emissions during kitchen waste composting

Compost supplementation with nutrients and microorganisms in composting process.

Comparative study of lead sorption onto natural perlite, dolomite and diatomite

Impact of struvite crystallization on nitrogen losses during composting of pig manure and cornstalk.

A laboratory scale experiment of composting in a forced aeration system using pig manure with cornstalks was carried out to investigate the effects of both phosphogypsum and dicyandiamide (DCD, C2H4N4) as additives on gaseous emissions and compost quality. Besides a control, there were three amended treatments with different amounts of additives. The results indicated that the phosphogypsum addition at the rate of 10% of mixture dry weight decreased NH3 and CH4 emissions significantly during composting. The addition of DCD at the rate of 0.2% of mixture dry weight together with 10% of phosphogypsum further reduced the N2O emission by affecting the nitrification process. Reducing the phosphogypsum addition to 5% in the presence of 0.2% DCD moderately increased the NH3 emissions but not N2O emission. The additives increased the ammonium content and electrical conductivity significantly in the final compost. No adverse effect on organic matter degradation or the germination index of the compost was found in the amended treatments. It was recommended that phosphogypsum and DCD could be used in composting for the purpose of reducing NH3, CH4 and N2O emissions. Optimal conditions and dose of DCD additive during composting should be determined with different materials and composting systems in further study.

Fang Dai

Papers

Use of potassium dihydrogen phosphate and sawdust as adsorbents of ammoniacal nitrogen in aerobic composting process.

Production and concentration change of ammonia in aerobic compost