Study On The Effects Of Calcium Minerals And Goethite On Anaerobic Digestion Of Organic Matters

Anaerobic digestion is one of the effective ways for the treatment and reutilization of organic waste biomass.However,the methane yield was much and treatment efficiency was lower than the theoretical value.Recently promotion of anaerobic digestion process with the addition of inorganic mineral materials is paying more and more attention.In the current study several abundant minerals?calcium minerals,limonite?were explored as additives to improve the methane production yield and promote the anaerobic transformation of organic waste.The major research content and results were listed as follows:1)Effects of four kinds of calcium minerals,calcite,dolomite,gypsum and anhydrite on anaerobic methane production from organic wastewater were studied using the brewery wastewater as representative.Results showed that the removal efficiency of COD reach above 88%,while the control group was only 82%.On the other hand,the CH₄ yield was significantly increased,especially the promotion effect of dolomite,the accumulative methane production increased by 55%compared to the control.2)Effects of limonite on the methanogenic process of solid organic wastes were explored by using the mixture of livestock manures and corn straw,blue algae and corn biomass as the feedstock.As for the study of anaerobic digestion of livestock manures and corn straw,the addition of natural limonite can effectively promote the methane yield from.Compared to the control,when the concentration of limonite was 0.3 g/L,the biogas production in the reactor added with chicken manure,pig manure and cow manure were increased by?33.65±2.51?%,?23.55±3.69?%and?37.46±3.88?%respectively.In the blue algae and corn straw reactors,the addition of limonite enhanced the methane production yield.The yield of methane in the reactor with limonite was?290±22?mL/g VS,while the control was only?253±23?mL/g VS.3)Anaerobic biological filter constructed using limonite,mixture of limonite and gypsum were explored to investigate the treatment efficiency of domestic sewage.The removal efficiency of COD,N,P in domestic sewage was monitored.Results showed that efficiency of anaerobic biological filter constructed with mixture of limonite and gypsum was more effective.After a long term operation period,the removal efficiency of COD,ammonia nitrogen,nitrate nitrogen and phosphorus reached?88.15±0.84?%,?57.86±6.72?%,?60.97±3.45?%and?59.81±4.95?%,respectively.