3种菌剂对小麦秸秆好氧堆肥降解效果比较

Effects of three microbial agents on wheat straw aerobic composting

为探讨不同菌剂接种对小麦秸秆好氧堆肥一次发酵阶段的处理效果,选用3种商业菌剂QD、DH和VT,并以厨余垃圾作为调节剂,进行了好氧堆肥发酵实验。通过研究堆肥过程中物料的温度、含水率、浸提液理化性质、挥发份固体(VS)含量和C/N比的变化情况,比较了3种菌剂对小麦秸秆好氧堆肥降解效果的影响。结果表明,QD、DH和VT处理下的物料均经历了升温、高温和降温期,温度峰值分别达到58.2、54.7和53.7℃,高温期分别维持了9、6和6 d;含水率和电导率(EC)均呈现先上升后下降的趋势;E4/E6、VS和C/N比均呈现降低的趋势;pH分别稳定在8.44、8.42和8.48;VS减少含量分别为18.87%、24.48%和22.08%。综合各项指标可看出,QD可以提高堆肥温度并满足堆肥无害化要求,DH可以促进物料中有机物的矿质化程度,3种菌剂对堆肥中腐殖质的形成和积累有着一定的促进作用。该研究结果可为筛选研制高效降解小麦秸秆的微生物菌剂提供理论基础,为解决受控生态生保系统(CELSS)中小麦秸秆等固体废物的资源化处理问题提供参考。

This experiment was designed to discuss the effects of different microbial agents on wheat straw degradation during the first aerobic composting stage.Three microbial agents(named as QD,DH and VT)were selected for the wheat straw and food waste aerobic composting,which were used as the main materials and nutrient additive,respectively.During the experiment,temperature,water content,physicochemical properties of extracts,volatile solid(VS)content and C/N ratio were studied,and the degradation efficiencies with different microbial agents were compared.The results showed that with QD,DH and VT addition the processes had all experienced heating,thermophilic and cooling phases,and the peak temperature reached 58.2,54.7 and 53.7℃,and the high temperature period kept 9,6 and 6 d,respectively.Water content and EC displayed the tendency of rising up at the beginning and declining in late.E4/E6,VS and C/N ratio showed a trend of decreasing.pH was stable at 8.44,8.42 and 8.48,respectively.The reduction content of VS was 18.87%,24.48%and 22.08%,respectively.In conclusion,QD can improve the composting temperature and meet the harmless requirements;DH can promote the mineralization of organic matter in the materials,and all the microbial agents have a positive influence on the formation and accumulation of humus in the composting.This experiment can provide the theoretical basis for screening and cultivating efficient bacterial strains for wheat straw composting,and also suggests some solutions for the resourceful treatment of biomass solid waste(particularly wheat straw)in CELSS.