Enhancement Of Start-up And Demand Characteristics Of Alkalinity For Anaerobic Sequencing Batch Reactor

The discussion on process performance and start-up of ASBR system was on initial stage. ASBR process was characterised by relatively slow start-up and alkalinity demand similar to other high-rate anaerobic processes, and did not make full use of intrinisic kinetic advantages. Experimental works in this paper were focused on rapid start-up and minimization of alkalinity for ASBR, and objectives were: to exploit an enhancement technical method for ASBR rapid start-up, to present the process strategies to develop type A granular sludge predominated by Methanosarcina, and to achieve minimum alkalinity supplement. The methods and achievements in this paper were following :(1) Influences of three kinds of flocculating agent on specific methanogenic activities(SMA) were assessed using anaerobic toxicity assay(ATA), which were polychlorinated alumina (PAC), polyacrylamide (PAM) and polyquaternary ammonium salt(PQA), respectively. The anaerobic biodegradabilities of PAC, PAM,and PQA were investigated by biochemical methane potential(BMP) test. The settling performances and strength of bioflocculates were discussed using zone settling velocity(ZSV) and sludge volume index(SVI).From the results, PQA was finally selected as an accelerating agent to enhance granulation at start-up of anaerobic reactor, and tests gave dose in the range of 10~20mg/L, the ratio of PQA/sludg concentration was 1.6~3.2mg/g. It showed the method of once two days of adding PQA was the most effective for granulation. Further, that was put forword the influences of flocculating agent on SMA, settling performances and strength of bioflocculates, and anaerobic biodegradabilities of flocculating agent and dosage added should be regarded as indexes to...