Effect Of Different Additives On Anaerobic And Aerobic Processing Duriing Bio-degradable Organic Waste Treatment

Biodegradable organic solid wastes come from a wide range of sources with a huge amount.The main treatment methods for biodegradable organic solid wastes are anaerobic digestion(AD)and aerobic composting.Therefore,based on the enhancement of direct interspecific electron transfer(DIET)process,the mechanism of improving the efficiency of anaerobic digestion and aerobic composting of biodegradable solid wastes by different additives was revealed.For aerobic composting of biodegradable solid wastes,the mechanism of improving the efficiency of anaerobic digestion and aerobic composting by different materials was studied,which is of great significance to realize its resource utilization through cleaner composting and anaerobic digestion treatment project.The results show that:In AD,thermally modified bentonite is a favourable source for enhancing methane yield from AD of chicken manure(CM).The maximum yield occurred when bentonite was calcined at 300 ? and 400 ?.Improved adsorption capacity and stabilization were observed in thermally modified bentonites,which mitigated the negative impacts of total ammonia nitrogen(TAN),free ammonia(FA),and pH on the digestion process.SEM images and EDS spectra revealed that pore adsorption and release of trace elements/cations might be the mechanism involved in enhanced methane production and also increased digestion of CM significantly.For better application,continuous experiments at intensive scale are necessary to confirm that thermally modified bentonite is also suitable for long-term digestion.Furthermore,microbial community analysis also should be performed in order to understand the responses of microbial communities to bentonite addition.The application of biochar could effectively enhance AD performance by accelerating the transformation of macromolecular substances to dissolved substrates,and increasing the buffering capacity of the AD system.Different types of biochar could improve methane production to different extent.fruitwood char pyrolyzed at 550'C achieved the highest cumulative methane yield of 294 mL/g VSadded,which is 69%higher than that of the control.Fruitwood char pyrolyzed at 550? also exhibited the largest specific surface area and highest TAN reduction capacity.Application of fruitwood biochar in AD is a sustainable and cost-effective practice that not only enhances the energy output but also allows for the reduction of operating costs.In composting,use of apple pomace(AP),citric acid(CA),elemental sulphur(ES),phosphoric acid(PA),magnesium hydrogen phosphate(PM),and calcium superphosphate(CP)additives had no negative effect on the sewage sludge compost sanification,but they improved N conservation through NH3 loss reduction.Compared to other treatments,the addition of CP increased the salinity of the compost;while the additions of ES and PA resulted in low NH3 volatilization,high N20 emissions,higher salinities,and compost products with low maturity.The related compost N loss,GHG emissions,and product maturity evaluation indicate that AP,CA,and PM are promising additives for use in producing high-quality compost.The addition of palygorskite significantly extended the duration of the thermophilic phase,promoted compost detoxification,accelerated organic matter degradation,and improved nitrogen conservation during the aerobic composting of biosolids.Moreover,the addition of palygorskite reduced the CH4,NH3,and N2O emissions,favored the reduction of DTPA-extractable Cu,Zn,Pb,and Cd contents,enhanced estrogen degradation during the biosolids composting,benefited the maturity of compost,and enhanced the quality of the end product.In aspect of economic efficiency,palygorskite addition at a proportion of 2%is recommended for biosolids composting.