Effect Of Different Modified Peanut Shell Charcoal On Municipal Sludge Composting

This paper studied the effect of different modified peanut shell charcoal on municipal sludge composting.The amount of sludge generated in China is increasing every year.The disposal of sludge has been concerned.Once it is handled carelessly,it may cause "secondary pollution" to the environment.At present,one treatment method suitable for sludge disposal is sludge composting.Utilization.Sludge aerobic composting can reuse sludge resources,but the harmful heavy metal content in sludge is the main obstacle to the application of sludge aerobic composting.Therefore,how to remove or passivate heavy metals in sludge is to solve the utilization of sludge composting resources.Premise.In this study,municipal sludge and wheat straw were used as composting materials,and 5%,15%,25%H2O2 modified peanut shell charcoal and 5%,10%,15%KOH modified peanut shell charcoal were added respectively.The carbon-nitrogen ratio was adjusted to 25:1 and the water content was 65%for composting.The whole process of temperature,pH,conductivity and water content during composting was monitored.The nutrients N,P,K and heavy metals Cu and Zn were observed before and after composting.The total amount of Mn and the exchangeable state,the reducible state,the oxidizable state,and the residual state were measured.research shows:(1)The addition of H2O2 and KOH modified peanut shell charcoal has little effect on the temperature,pH,water content and conductivity of the municipal sludge composting process.However,since the peanut shell charcoal itself is alkaline,the pH value of the whole process of adding the peanut shell charcoal is greater than that of CK,and the peanut shell charcoal with 15%KOH modified has the highest pH,because more KOH treatment is introduced.OH-(2)Adding H2O2 and KOH modified peanut shell charcoal can effectively improve the N,P and K contents of the heap after composting.After adding 25%H2O2 modified and 10%KOH modified peanut shell carbon compost,the highest growth rate of ammonium nitrogen was 29.58%,22.22%;25%H2O2 modified and 10%KOH modified peanut shell The growth rate of nitrate nitrogen in the carbon fertilizer composting was the highest,52.50%and 47.60%respectively;the 25%H2O2 modified and 10%KOH modified peanut shell carbon compost had the highest growth rate of total phosphorus,27.26%and 21.07%respectively;25%H2O2 modified and 10%KOH modified peanut shell carbon compost ended the highest growth rate of available phosphorus,32.61%,32.61%;25%H2O2 modified and 10%KOH modified peanut shell carbon compost ended The highest potassium growth rate was 13.89%and 19.64%respectively;25%H2O2 modification and 10%KOH modified peanut shell carbon compost ended the highest growth rate of available potassium,24.74%,21.09%,respectively,so 25%H2O2 The modified peanut shell charcoal is more conducive to the improvement of the heap fertilizer efficiency.(3)The mass fraction of H2O2 modified peanut shell carbon test group was 25%.After H2O2 modification,the passivation effect of peanut shell charcoal on Cu、Zn、Mn was more obvious.The passivation efficiency was 35.68%,26.70%and 25.46%,respectively.In the KOH modified peanut shell charcoal test group,the 10%KOH modified peanut shell charcoal has the most significant passivation efficiency for heavy metal Cu、Zn、Mn,which are 34.74%,25.40%and 24.35%,respectively,and can be obtained after 25%H2O2 modification.The peanut shell charcoal has a good passivation effect on heavy metals such asCu、Zn、Mn。...