Parameters optimization for vermicomposting of cow dung and changes of properties of composting residues
Vermicomposting is one of the ways to utilize livestock and poultry manure resources.In this study,cow dung was used as the main material,supplemented with different additives in the vermicompost reactor.The suitable parameters were optimized for the production of vermicompost by using the L16 (44+32 ) orthogonal design,and fur-ther study was conducted to reveal the changes of physicochemical properties and adsorption properties on Pb2+and Cd2+of the composting residues.The results showed that both rice bran and the effective microorganisms (EM) bac-terial agent could promote the growth and reproduction of earthworms,and improve the physicochemical properties of the derived composting residues.It was feasible to add biochar,struvite and shell powder into the cow dung vermi-compost reactor.The best adsorption effect for Pb2+and Cd2+was found in the derived composting residues from cow dung vermicompost reactor with struvite addition,and their adsorption rates reached up to 96.50％ and 49.95％,re-spectively.The optimized parameters for the cow dung vermicomposting were as follows∶the mixture of cow dung,rice bran and EM bacterial agent at the mass ratio of 7∶3∶1 was used as the main material,supplemented with 4％(mass fraction) struvite or biochar,with the moisture content of 70％-80％,inoculated with 12 earthworms based on 150 g dry substrate,and vermicomposted for 40 days.The present study could provide scientific basis for the utili-zation of livestock and poultry manure,and the prevention of the migration of Pb2+and Cd2+in the soil.
vermicompostingeffective microorganism (EM) bacterial agentstruvitebiocharheavy metal
万方数据
维普
