Effect and mechanism of paddy soil-enhanced simultaneous decontamination and resource recovery by aerobic granular sludge
Aerobic granular sludge(AGS)technology shows a great potential in simultaneous wastewater treatment and resource utilization,and how to enhance AGS technology is one of important research topics to promote its green development.Based on the excellent properties of the natural paddy soil which has the redox micro-environment and organic colloidal substances,it was proposed to introduce paddy soil into AGS system as a new inoculation source.Then the effects of adding paddy soil on the decontamination efficiency of the reactor,sludge granulation process,alginate-like exopolysaccharides(ALE)secretion,and microbial community structure were studied.The mechanism of simultaneous enhancement of AGS decontamination and reclamation through adding paddy soil was analyzed.The results indicated that when the inoculation ratio of paddy soil to activated sludge was 2:3,the start-up time of the reactor with paddy soil was about 30 days earlier than that of the control group.The SVI30 of mature granular sludge was about 76 mL·g-1,the MLSS was about 1.5 g·L-1,the average particle size reached 653.8 pm,and the ALE yield was 21.75 mg·g-1VSS.These characteristics were significantly better than those of the control group.In addition,the addition of paddy soil enriched the dominant bacteria OLB8(17.6％),Thiothrix(11.1％)and Micavibrionales(8.2％)in AGS,which contributed to the removal of total nitrogen from wastewater,and carbon capture as well as conversion to ALE.This study can provide method guidance for rapid start-up,stable operation and recovery of high value-added products of AGS system.
国家科技期刊平台
NSTL
万方数据
