Effect Of Graphene Oxide/Graphene On Anaerobic Gas Production Performance Of Sludge

Municipal sludge is a kind of heterogeneous micelle with complex composition.If a large number of municipal sludge is stored everywhere or put into the sea without scientific and effective treatment,it will not only cause serious pollution to the environment,but also cause waste of resources.The improper treatment and disposal of municipal sludge will cause a series of problems,such as occupying land,producing odor gas,breeding mosquitoes and flies,endangering the growth of animals and plants,and polluting water bodies.Using scientific and effective sludge treatment and disposal technology can not only avoid the occurrence of a series of environmental problems mentioned above,but also utilize the residual organic matter in sludge to convert it into clean energy and realize the comprehensive utilization of waste.Anaerobic digestion technology can realize the harmlessness,reduction,stabilization and resource utilization of sludge,so it is one of the most widely used municipal sludge treatment and disposal technologies at home and abroad.The traditional sludge anaerobic digestion technology has the characteristics of long reaction period,low anaerobic rate and gas production efficiency,low biogas production and low methane content in biogas.Therefore,it has become a research hotspot to find new technologies for sludge treatment and disposal in cities and towns or to add appropriate materials to promote gas production in the process of anaerobic digestion.It was found that carbon-based functional materials could accelerate anaerobic digestion rate,increase gas production and methane production,and realize sludge recycling.The effect of graphene oxide and graphene oxide on anaerobic gas production of sludge was studied by using sludge solution with a certain solid-liquid ratio as substrate.The optimum concentration of graphene oxide and graphene was selected according to daily gas production,cumulative gas production,daily methane production,cumulative methane content,TCOD_Cr,SCOD_Cr,ammonia nitrogen,TN,phosphate and TP.?1?Study on the effect of graphene oxide on anaerobic gas production of sludge.In this study,seven groups of experiments were set up with blank I?0 mg/L graphene oxide?and blank II?no inoculum?.The concentration of graphene oxide was20,40,60,80 and 100 mg/L,respectively.It was found that the removal rates of TCOD_Crr and SCOD_Crr in the experimental group with 80 mg/L graphene oxide were the highest,67.34%and 78.82%respectively,27.48%and 33.68%higher than blank I?0mg/L graphene oxide?,24.24%higher than blank I?0 mg/L graphene oxide?,and20.12%higher than the cumulative methane content.The ammonia nitrogen of the experimental group with 100 mg/L graphene oxide concentration was unstable.The removal rates of TCOD_Crr and SCOD_Crr were the lowest,55.32%and 70.13%respectively,which were 0.77%and 6.48%higher than that of blank I?0 mg/L graphene oxide?.The cumulative gas production was 9.07%lower than that of blank I?0 mg/L graphene oxide?and the methane content was 4.90%lower than that of blank I?0 mg/L graphene oxide?.The removal rates of TCOD_Crr and SCOD_Crr were the lowest,respectively,with 80 mg/L graphene oxide The average pH of the experimental group was 7.78,indicating that appropriate concentration of graphene oxide had a better control effect on the pH of the system.Therefore,within the concentration range of graphene oxide studied,80 mg/L of graphene oxide is conducive to the anaerobic digestion of sludge,while 100 mg/L of graphene oxide can inhibit the anaerobic digestion of sludge.?2?Study on the effect of graphene on anaerobic gas production of sludge.In this study,seven groups of experiments were set up with blank I?0 mg/L graphene?and blank II?no inoculum?.The concentration of graphene was 20,40,60,80 and 100 mg/L,respectively.The experimental results show that the removal rates of TCOD_Crr and SCOD_Crr with 100 mg/L graphene are the highest,68.61%and 71.88%respectively,which are 24.02%and 45.63%higher than that of blank I?0 mg/L graphene?,35.23%higher cumulative gas production and 25.71%higher methane content than that of blank I?0 mg/L graphene?.Therefore,within the range of graphene concentration studied,the effect of graphene concentration of 100 mg/L on anaerobic digestion of sludge is obvious.In summary,the addition of appropriate concentration of graphene oxide and graphene in sludge anaerobic digestion process is conducive to sludge anaerobic digestion.