Study On Rapid Start-up Method Of Anaerobic Reactor

Due to the long generation cycle of anaerobic micro-organisms,the anaerobic reactors exit the common disadvantage of long-term of start-up.In general,the anaerobic reactor start-up time often takes several months or even longer,which to some extent affected the application of anaerobic technology.In addition,the high cost of the alkalinity during the operation of the anaerobic reactors is related to the economic viability of anaerobic process directly.The main purpose of this paper is to reduce the start-up times of anaerobic reactors and reduce the alkalinity dosage during the operation of anaerobic reactors.The seed sludge used in the test was anaerobic sludge,which preserved in the laboratory, and the sludge has been some of the characteristics of granular sludge.The wastewater was the artificial high concentration organic wastewater.Anaerobic reactor rapid start-up test was proceeded in the conditions of different volume load and alkalinity,and the removal rate of COD and the VFA were the control indexes,to investigate the starting speed and operating conditions under different starting strategies.In the best conditions,which were determined by laboratory simulated wastewater,the application of quick-start technology in industrial wastewater also was disscussed.The subject also compared the similarities and differences between UASB and ABR in the process of starting and operation,and analysed the technical and economic of the quick-start technology.The results of the test showed that,the best starting conditions of UASB are as follows: volume load 2.0kg/(m~3·d)),COD concentration about 2000mg/L,influent alkalinity 1500mg/L,HRT=24h and temperature 20～30℃.Under the conditions,UASB can start-up successfully in 10～15d and operate stably.After the success,UASB can operate stably under the conditions of low alkalinity,about 1000mg/L.And the best starting conditions of ABR are as follows:volume load 4.0kg/(m~3·d)),COD concentration about 4000mg/L,influent alkalinity 1000mg/L,HRT=24h and temperature 18～30℃.Under the conditions,UASB can start-up successfully in 7d around and operate stably.After the success,ABR can operate stably under the conditions of low alkalinity,about 500mg/L.The results of industrial wastewater application test showed that,in the best starting conditions,determined by simulated wastewater test in laboratory,saponin wastewater can not start up UASB successfully,and fruit juice wastewater can achieve the rapid start successfully, but should be operated stably in the conditions of higher alkalinity.While for ABR,with saponin wastewater and LAS wastewater,both can achieve rapid start of ABR successfully, and can operate stably in the conditions of lower alkalinity after starting-up.Comparative test results showed that,in best starting conditions,in the ways of starting conditions,starting speed,shock resistance capacity,alkalinity demand,processing capacity and treatment efficiency,etc,ABR was superior to UASB.Compared with conventional starting,quick-start technology was more ecnomical.