| Bio-electrochemical system assisted anaerobic baffled reactor(BES-ABR)can deal with high concentration organic wastewater and seperate phases at the same time.Besides,it can reduce the accumulation of volatile fatty acids;Upflow Anaerobic Sludge Blanket(UASB)reactor is a classical technique of anaerobic biological treatment,good for anaerobic granular sludge cultivation,has adaptability for many types of wastewater,doesn't need special separate equipment,hydraulic situation is good.These experiments are aimed at the operate characteristics of BES-ABR,mesophilic UASB,thermophilic UASB reactor,in which the ABR volume is 3.5L,UASB volume is 5L.The mesophilic temperature scale is(35±1)? as the thermophilic temperature scale is(52.5± 2.5)?.The experimental results show that the experimental operation in contrast to mesophilic BES-ABR and UASB,mesophilic UASB and thermophilic UASB,under same temperature,BES-ABR can deal higher sludge hydrothermal dewatering filtrate concentration than UASB;the gas production of thermophilic UASB is higher than mesophilic UASB,but lower removal rate of COD and gas production efficiency.When the influent sludge hydrothermal dewatering filtrate COD concentration is 19000mg/L,BES-ABR COD removal rate kept above 75%;daily volume production of CH4 can reach 1600 m L/(L.d);total VFA concentration scale is 6000-13000 mg HAC /L,the removal rate of VFA gradually increased from 60% to more than 85%;The range of ammonia nitrogen that inhibits methane production is 1.76-2.20g/L,the removal rate of ammonia nitrogen was stable at about 27%;each compartment sludge loading kept at 0.14~0.39,0.035~0.20,0.078~0.11,0.078~0.15 kg COD/(kg SS.d)to make sure more than 54% COD removal rate,respectively,the best sludge loading in each compartment are 0.14,0.035,0.078,0.078 kg COD/(kg SS.d);volume loading in each compartment which were maintained at 2.81~14.68,0.89~8.02,0.97~6.17,0.94~6.38 kg COD/(m~3.d)can make sure more than 54% of COD removal rate,the best volume loading in each compartment are 6.24,1.75,2.18,2.12 kg COD/(m~3.d).COD removal rate of mesophilic UASB after the stable operation is about 75%,the sludge hydrothermal dewatering filtrate COD concentration limit of mesophilic UASB is between 17080-18510mg/L;single day single reaction volume of CH4 production is 8.90~239.86 m L/(L.d),when the concentration of COD increase to 18510mg/L,the gas production performance nearly drop to zero;when the influent COD concentration is below 18510mg/L,the removal rate of VFA was stable at about 97%;when the influent COD concentration is less than 17080mg/L,the removal rate of NH4+-N ranges from 25%-50%;sludge loading scale is 0.06~0.39 kg COD/(kg SS.d),the best sludge loading scale is 0.22~0.39 kg COD/(kg SS.d);volume loading scale is 3.14~19.16 kg COD/(m~3.d),the best volume loading is 19.16 kg COD/(m~3.d).When hermophilic UASB is stable,the removal rate of COD is above 65%;CH4 production is from 14.58 to 520.24 m L/(L.d);the removal rate of VFA reaches 85%,and then increase the influent COD to 24000mg/L,the removal rate of VFA decline in 186 th days,the effluent VFA reached 6243 mg HAC/L,VFA removal rate is only 48%,it means that the reactor has been acidified,effluent VFA concentration is directly related to acidification;the NH4+-N inhibited concentration is range 0.97 to 1.45g/L,compare to other research,it's much more narrow,and after that,it changes little;the effluent p H is in the range of 6.99~7.97,and after the reactor operation is stable,it is basically stable at around 7.7;the alkalinity of effluent is in the range of 2157.38~7665.37 mg Ca CO3/L;ORP is in the range of-186~-419 m V,most fall in the scale of suitable methanogens gas-producing range;the best sludge loading scale is 0.10~0.24 kg COD/(kg SS.d),the optimum volume loading scale is 13.29~15.08 kg COD /(m~3.d). |
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