超声波强化微生物对偶氮染料AO7的生物降解机理研究

建立了SBR反应器中超声波辐射和好氧活性污泥联合作用的方法,研究了超声波对偶氮染料AO7生物降解的影响.最优操作参数为:超声波强度,6.4 W/L;进水葡萄糖浓度,2 000 mg/L;曝气流量,0.4 mL/min;超声波辐射时间间隔,5min;超声波频率,25 kHz.超声波强度与进水葡萄糖浓度是影响AO7生物脱色的主要因素.生物脱色速率先是随超声波强度的增加而增加,达到一定程度后超声波强度的增加反而使脱色速率降低.生物脱色速率随着进水葡萄糖浓度增大而增大.实验同时发现超声波可以加速微生物对AO7降解产物的进一步降解.超声波辐射对微生物的膜渗透性有一定作用,随着超声波强度的增加,微生物的膜渗透性增大,但膜渗透性的增大与微生物对AO7的加速降解不成线性关系.

Improvement of Acid Orange 7 Biodegradation by Ultrasound Assisted Bioreactors

A combination technique of ultrasound(US) exposure and aerobic activated biomass in a Sequencing Batch Reactor(SBR) has been developed.The study was carried out to investigate the effect of US on the biological color removal of textile effluents containing azo dye Acid Orange 7(AO7).The optimum parameters were found to be: US intensity,6.4 W/L;glucose influx,(2 000) mg/L;aerate flux,0.4 mL/min;US exposure interval,5 min;US-frequency,25 kHz.US intensity and glucose influx were the predominating factors.The bio-decolorization rate increased as US intensity increased,at a certain level it decreased if US intensity continually increased.The decolorization rate had been improved with the increasing of glucose influx.Based on the experiment data,it was found that the US exposure not only significantly increased AO7 bio-decolorization rate but the bio-degradation efficiency of AO7 degradation product.The cell membrane permeability was improved by US exposure.However no linear relationship between the improvement of permeability and the bio-decolorization rate was found.