Study Of Micro-electrolysis And Biological Technology In Refractory Industrial Wastewater Treatment

The situation of industrial wastewater pollution in China is serious,during more than 500 major rivers,more than 80%of rivers were contaminated with different degrees in our country at present.The main reason is that the emissions of a large number of different types of refractory wastewater,the wastewater will pose a large threat to water environment and human health,at the same time,the the sustainable development of related industries in our country were also greatly restricted.Therefore,the refractory industrial wastewater(dye wastewater and pharmaceutical wastewater)is major research object in this study,micro-electrolysis and biological technology were applied to the wastewater treatment.The main research contents and conclusions are as follows:(1)The preparation and performance tests research of iron-carbon micro-electrolytic material.The preparation process of iron-carbon micro-electrolysis material was as follows:the mass ratio of Fe2O3/C was 1:1 in the every 100 g of raw material,Fe2O3 and carbon powder were all 45 g,TiO2 was 6 g,carboxymethyl cellulose was 2 g,walnut shells powder was 2 g,sintering temperature was 900 ? and sintering time is 1 h.The optimize conditions of the iron-carbon micro-electrolysis in the wastewater treatment were as follows:initial pH was 3,the dosage of iron-carbon material was 66 g/L,aeration time was 1.5 h,coagulation time and pH were 11 and 1.5 h respectively.The iron-carbon micro-electrolysis material is applied to static beaker treatment of dye and pharmaceutical wastewater,the COD removal efficiency of more than 60%can be reached,the COD removal efficiency of pesticide wastewater reached more than 45%,the COD removal efficiency of papermaking wastewater reached more than 35%,and the removal efficiency of total chromium of electroplating wastewater reached more than 90%.For all these wastewaters treating by micro-electrolysis material,the color reduced to below 40 times.The structure of the dye molecules in the dye wastewater are destroyed after micro-electrolysis treatment,especially the main chromophoric groups of dye molecules were destroyed,the color of the dye wastewater was greatly reduced.(2)Study on the continuous iron-carbon micro-electrolysis process and continuous iron-carbon micro-electrolysis-UASB-SBR technology in dye wastewater treatment.The continuous iron-carbon micro-electrolysis process displayed good performance in treatment of the wastewater,with a color removal of 75%and COD removal of more than 60%.Effluent reflux technology can effectively reduce the amount of alkali used in the process.Sludge recycling can be research direction in the future.The power type kinetic equation was applied in the degradation of COD in the wastewater,the dynamic equation of the fitting was V=2.26x10-9 C2.86.Only UASB was applied to treat the actual dye wastewater,the wastewater can produce strong inhibition to UASB,the COD removal efficiency and gas production greatly reduced.The continuous iron-carbon micro-electrolysis-UASB-SBR process treated the wastewater,the COD removal efficiency of the combination process reached around 91%,the COD of the effluent declined to 70-98 mg/L,and the combination process exhibited a high ability to resist loading shock.The removal rates of total COD were ranked from high to low in the following order:iron-carbon micro-electrolysis>SBR>UASB.Iron-carbon micro-electrolysis can be effectively combined with a UASB-SBR by optimization of the HRT.(3)Preparation and application of aluminum-carbon microelectrolysis materials in high alkaline dye wastewater treatment.The optimum conditions for the ACMM were a mass ratio of aluminum to carbon of 1.26,a TiO2 mass percentage of 4.78%,an adhesive carboxymethyl cellulose mass percentage of 2%,a walnut shells powder of 3.54%,a sintering time of 88.5 min,and a sintering temperature of 500?.The optimize conditions of the aluminum-carbon micro-electrolysis in the wastewater treatment were as follows:initial pH was 12,the dosage of iron-carbon material was 200 g/L,and aeration time was 9 h.During the stable operation period of the continuous aluminum-carbon micro-electrolysis process,the COD improved by more than 50%,more than 50%of the NH4+-N was removed,color removal efficiency was higher than68%,and the biodegradability of the wastewater significantly improved.(4)The study on the development of biotechnology the PVA(polyvinyl alcohol gel balls used as biological carrier)in the pharmaceutical and dye wastewater treatment?In the aspect of anaerobic treatment of pharmaceutical wastewater,UASB filled with polyvinyl alcohol(PVA)gel beads(1#UASB);a UASB filled with traditional anaerobic granular sludge(2#UASB);and a UASB filled with traditional anaerobic granular sludge and granular active carbon(3#UASB).The domestication times for the 1#UASB,2#UASB,and 3#UASB reactors were 30,47,and 47 days,respectively.When the volume load was up to 7 kg COD/(m-d),the COD removal efficiency of the 1#UASB,2#UASB,and 3#UASB stayed in the range of 69%to 75%(deviation 1.8%),46%to 69%(deviation 8.6%),and 61%to 73%(deviation 4.0%),respectively.The highest the volume load reached for the 1#UASB,2#UASB,and 3#UASB were 12,7,and 8 kg COD/(m3·d),respectively.High-throughput pyrosequencing analysis showed that Levilinea,Syntrophorhabdus,Desulfovibrio and Acetobacterium were the dominant bacteria in the 1#UASB,2#UASB,and 3#UASB reactors' granular sludge.The bacteria abundance in the 1#UASB sludge were higher than for the 2#UASB and 3#UASB granular sludge.?PVA aerobic process treat the actual dye wastewater,the volume load of PVA process can reach to 2.2 kgCOD-m-3/d,temperature control was 30 ?,influent pH was 7.5,ratio of carbon to nitrogen was 140:1,the DO was 2.9-3.0 mg/L,the average COD removal efficiency of the PVA aerobic process rate reached around 85%,and with the increase of the concentration of the influent COD,the effluent COD was stability in range of 100-200 mg/L.During the long-term stable operation,production rate of excess sludge was 0.083 kgMLSS/(kg COD),this production rate is far lower than the traditional activated sludge process(0.5 kgMLSS/(kg COD));? Study on the improvement of micro-electrolysis process and in combination with PVA aerobic process,reverse osmosis filtration was set at the bottom of the micro-electrolysis reactor,and continuous aeration micro-electrolysis was instead of aeration micro-electrolysis combined aerobic micro electrolysis.The improved micro-electrolysis technology can reduce energy consumption and backwash water,the COD removal efficiency was steady at more than 60%.Dye wastewater was treated by micro-electrolysis-PVA aerobic process,influent COD was in the range of 500-660 mg/L,effluent COD of the micro-electrolysis was in the range of 140-380 mg/L,effluent COD of the PVA process was in the range of 68-140 mg/L.The COD removal efficiency of micro-electrolysis-PVA aerobic process was between 73%and 84%.