Experimental Study On Rapid Start-up Of UASB Reactor

In recent years,with the rapid development of industry and agriculture,water pollution has become increasingly serious.The effective treatment of waste water has become the primary concern of contemporary people.Up-flow Anaerobic Sludge Blanket?UASB?can not only effectively degrade organic matter in wastewater,cultivate granular sludge with better performance,but also reduce pollution.It is widely used in anaerobic wastewater treatment.The formation of Anaerobic Granular Sludge?AGS?is a symbol of the successful start-up of the UASB reactor and an important part of ensuring the stable and normal operation of the reactor.However,there are many factors influencing the formation of AGS,which always affect the startup of UASB reactor,resulting in a relatively long startup time of the reactor.Therefore,this experiment will study the effect of adding cations,changing the organic load mode and different influent water quality on the reactor startup process,and conduct a comprehensive analysis of the changes of various indicators and the reactor operating effect in this process.The purpose of this experiment is to explore the anaerobic granular sludge that can be quickly cultivated,and to explore the conditions for the rapid start-up of the UASB reactor to provide a reference for practical applications.The results are as follows:?1?When the cationic dosage is 100mg/L,the sludge concentration can be effectively increased,the sludge activity can be improved,the gas production can be increased,and the formation of granular sludge can be promoted.Among them,the promotion effect of Mg²⁺on sludge granulation is the best,followed by Ca²⁺,and the promotion effect of Fe²⁺is the weakest.At the end of the experiment,the growth rate of VSS in Mg²⁺reaction bottle was measured to be 8.91g/l,the growth rate of VSS/TSS was 36.23%,particle size 0.25?0.5mm of granular sludge was 14.2%,and particle size?1mm of granular sludge accounted for 4.6%.?2?The organic load of the reactor is increased by increasing the COD concentration of the reactor inlet water,shortening HRT and the combination of the two.At the end of the experiment,the organic load of N₃ reaches 5.25kgCOD/?m³·d?,which exceeds the design load by 5kgCOD/?m³·d?,N₂ is 4.16kgCOD/?m³·d?,N₁ is only 3.5kgCOD/?m³·d?,indicating that simultaneously increasing the COD concentration of the influent and shortening the HRT can quickly improve the reactor OLR in a shorter time Make the reactor quickly reach the design load.?3?The actual wastewater?R1 reactor?is doped with simulated wastewater and the actual wastewater?R₂ reactor?is used as the inlet water quality to start the reactor.The results show that the reactor can be started in both cases,but the former is ahead of the latter 10d to complete the start.At the end of the experiment,the activity of sludge in both reactors was relatively high,and the majority of granular sludge with a particle size of less than 0.1mm,the sludge with a particle size greater than 0.45mm in R1 reactor was 13%,and the R2 reactor was only 8%.