ABSTRACT
The objective of this study was to investigate the performance of a laboratory-scale submerged membrane bioreactor (SMBR) system for the treatment of synthetic textile wastewater containing disperse red dye. The SMBR system was run aerobically in a continuous flow mode at five different hydraulic retention times (HRTs) of 24,18,14.4,11.28 and 8.4 h respectively, with an average permeate flux of 20 L/(m2 x h). The performance of the system was not adversely affected by decreased HRT and the consequent rise in the food/microorganism ratio (0.07 to 0.14 g BOD/(g SS x d)) and organic loading rate (OLR: 0.4 to 1.24 BOD kg/(m3 x d)). The average removal rate for COD, BOD and colour were 92.33%, 93.69% and 91.36%, respectively. To maintain a stable flux and prevent fouling, the membrane was covered with a cylindrical wire-mesh cage, and routine chemical backwashing and chemical cleaning procedures were adapted. Transmembrane pressure increased from 29.47 to 58.42 kPa (0.29 to 0.58 bar) during each run of HRT. The results indicated that synthetic textile wastewater could be treated very effectively by the SMBR system.
Subject(s)
Bioreactors , Coloring Agents/isolation & purification , Membranes, Artificial , Textile Industry , Ultrafiltration/methods , Waste Disposal, Fluid/methods , Biological Oxygen Demand Analysis , Biomass , Coloring Agents/chemistry , Equipment Design , Industrial Waste , Sewage , Waste Disposal, Fluid/instrumentationABSTRACT
Using the freezing-thawing procedure, a highly purified preparation of PPase from R. rubrum chromatophore membranes was incorporated into soybean phospholipid liposomes. The activity of reconstituted PPase was increased in the presence of the uncoupler, FCCP, and the antibiotics, valinomycin (+KCl) and nigericin (+KCl). Oligomycin did not exert any inhibiting action, while imidodiphosphate and NaF significantly decreased the activity of the PPase incorporated into the liposomes. Preincubation of both PPase and ATPase prior to their incorporation into the liposomes did not affect the activity of the reconstituted enzyme. It was concluded that the PPase from R. rubrum chromatophores when incorporated into the liposomes may function as a proton pump independently of the ATPase.
