Eureka! Institutional Repository

Μembrane Bioreactors (MBR) consist a relatively modern method widely applied in recent years in urban and industrial wastewater. They combine biological treatment with filtration through membranes for the separation of the final effluent from the suspended biomass. Their main advantage is that they can operate efficiently at very high concentrations of sewage, which can range from 5000-20000 mg / l, thus reducing the overall requirements of the tank volume. On the other hand main disadvantage of these systems is the clogging of the membranes, which affects both operational and financial terms. So on this project we examined the operation of a biological treatment’s pilot plant with membrane bioreactor at the premises of the ATEI Thessaloniki’s laboratory space, which treats industrial waste entering the facilities of the organic industrial zone of Thessaloniki without any pre-treatment, beyond that of sloughing. This specific waste is mainly characterized by the high organic load containing (average COD = 3000 mg / l). The reactor was in operation for more than 170 days and during this period three different residence times of solids (SolidRetentionTimes - SRTs = 30 , 20 and 15 days) were examined. The analyzes carried out, involved a) the examination of the influence of the SRT to the quality of the effluent, and b) the examination of the effect of the Hydraulic Retention  Time (HRT) to the output quality of the effluent at constant SRT equal to 20 days. The highest removals COD (99.2%) as well as small concentrations SMP observed for SRT = 20 days. Also in this SRT is significantly limited the phenomenon of clogging. The decrease of hydraulic retention time had a negligible effect on the removal of organic material.