光辅自耦合藻-菌颗粒污泥处理系统特性

Characteristics of light-assisted self-coupling algae-bacterial granular sludge treatment system

在当前温室气体成为生态环境严重威胁的背景下,探究了实验室条件下光辅助自耦合藻-菌颗粒污泥处理系统达到最佳处理效果时,系统所需的曝气量大小。本工作首先阐述了该系统的培养过程,接着考察了藻类供氧完全替代曝气(零曝气)的情况下系统处理效果,最后探究了适当增加不同曝气量(0.2,0.4,0.6,0.8 L/min)的条件下系统处理效果。结果显示,在零曝气条件下经过12 h的处理,出水COD、总磷、总氮浓度分别降至76.70,1.09,3.52 mg/L,各指标浓度下降趋势明显,继续增大水力停留时间出水能够达标,但处理成本随之增大。对比几种不同曝气量条件,在0.2 L/min曝气量条件下系统各项出水指标效果达到最佳,COD、总磷、总氮浓度分别降至25.6,0.40,1.67 mg/L。因此0.2 L/min为系统最佳曝气量,在保证处理效果的同时能够为污水厂节能减排带来可观效果。

Self-coupled microalgae-bacterial granular sludge(algal-bacterial granular sludge,ABGS)is a new type of granular sludge.Through the symbiosis of algae and granular sludge,it not only solves the problem that the algae suspension growth is difficult to collect and treat,but also can use the photosynthesis of algae to provide oxygen for aerobic granular sludge,saving a lot of energy consumption.It provides new ideas for solving the problem of excessive energy consumption in sewage plants.Under the background that greenhouse gases have become a serious threat to the ecological environment,to explore when the light-assisted self-coupling algae-bacterial granular sludge treatment system achieves the best treatment effect,the amount of aeration required by the system.In this work,the cultivation process of the system was first described,and then the treatment effect of the system under the condition that algae oxygen supply completely replaced aeration(zero aeration)was investigated.Finally,the treatment effect of the system under the condition of appropriately increasing different aeration rates(0.2,0.4,0.6,0.8 L/min)was explored.The results showed that after 12 h of treatment under zero aeration conditions,the effluent COD,total phosphorus,and total nitrogen concentrations decreased to 76.70,1.09,and 3.52 mg/L,respectively.The concentration of each index had an obvious downward trend,and the effluent can meet the standard by continuing to increase the hydraulic retention time,but the processing cost will increase accordingly.Therefore,it was necessary to appropriately increase aeration to improve the efficiency of sewage treatment.Compared with several different aeration conditions at the level of one-tenth of the aeration required by the aerobic granular sludge treatment system,under the condition of 0.2 L/min aeration rate,the effect of each effluent index of the system reached the best.The concentrations of COD,total phosphorus,and total nitrogen were reduced to 25.6,0.40,and 1.67 mg/L,respectively.Therefore,0.2 L/min was the optimal aeration rate of the system,which can bring considerable effects to the energy saving and emission reduction of the sewage plant while ensuring the treatment effect.