In this study, the combination of chemical, biological and MEMBRANE processes was investigated for landfill leachate treatment. In order to reduce the contamination level, the chemical coagulation process was used by coagulants such as aluminum sulfate and poly aluminum chloride. Also, the optimum pH range and concentration of the coagulant were determine following by the biological process of activated sludge. Finally, the leachate separation of the aerobic BIOREACTOR was carried out by FO-MBR MEMBRANE process and the effect of powder activated carbon adsorbent was studied on this process. The results showed that the amount of COD in leachate decreased by 48% after pretreatment using coagulants (optimum concentration of 1 g/l and pH = 8). Then, the COD removal rate reached to 24% by using the aerobic activated sludge process under optimum aeration conditions, F/M = 0. 312 COD/MLSS. d ratio and 24h hydraulic retention time. In the last section, the usage of synthesized cellulose MEMBRANE in form of the frame and plate modules immersed in the aerobic BIOREACTOR of the FO-MBR process, was examined. Furthermore, 2 g/l powder activated carbon adsorbent was used to improve the performance of this process and the reduction of MEMBRANE fouling, which improved the performance of the landfill leachate wastewater treatment system by increasing the COD removal rate from 74% to 92% as well as the changes in MLSS concentration during the 4-day FO-MBR process increased by 24% compared to the absence of adsorbent.

Bioethanol is a second generation biofuel that has recently received attention due to limited fossil fuel resources and air pollution cause of fossil fuels. In this study production of bioethanol from lignocellulosic material of corn fiber in a MEMBRANE BIOREACTOR was investigated. Acid pretreatment was used to increase the fraction of cellulose to 41%. The strain of saccharomyces cerevisiae was used as yeast. In most previous works the experimens have been performed in batch systems, whereas in this study simultaneous saccharification and fermentation (SSF) were performed in a continuous ultrafilteration MEMBRANE reactor, where the product is removed to prevent the inhibitory effect of the product on bioethanol production yield and enzyme deactivation. Experimental design and optimization was carried out by Design Expert software. The optimum conditions were determined to be: temperature (38.5°C), agitation speed (631.2 rpm) and surfactant concentration (0.08%v/v). Under these conditions the predicted ethanol yield was 87.8% and the actual experimental value was 84.2%.

MEMBRANE BIOREACTOR Technology (MBR) can be used as a one-stage process for treatment of various kinds of wastewater which produces good effluents for reuse. In this research using MBR for oily wastewater has been investigated. A tubular micro filtration MEMBRANE was used for separating and recycling biomass, suspension, and heavy molecules which leave the BIOREACTOR. The temperature was maintained between 34-36 C˚ and COD ranges 500-2000 mg/L. The removal efficiency was between 93-97 percent, and MLSS concentration in BIOREACTOR gradually increased to 16.2 g/L.

A 0.15 mm dead-end immersed hollow fiber MEMBRANE and filamentous fungus Aspergillus oryzae were used in a MEMBRANE BIOREACTOR (MBR) for treatment of baker’s yeast wastewater. The fungus was adapted to the wastewater in the BIOREACTOR for two weeks before continuous process. Average organic loading rate of 4.2 kg COD/m3.d was entered the BIOREACTOR. COD and BOD5 of the wastewater were reduced to 488 and 70 mg/L, respectively, over a period of 45 days, while the turbidity of the wastewater reduced from 134-282 NTU to less than 2.5 NTU in the permeate stream. Critical flux and a suitable operating flux were determined as 6.7 and 5 L/m2 h, respectively. The system was able to efficiently reduce the turbidity and suspended solid by 99.4% and 98.3%, respectively, resulting in a clear effluent.

The aim of this study was the increasing of leachate quality using integrated MEMBRANE BIOREACTOR (MBR). The reactor was fed with treated leachate with overall 70-1360 mg/l chemical oxygen demand (COD). The analysis of COD, biochemical oxygen demand (BOD5), total suspended solids (TSS), and total dissolved solids (TDS) were performed in feed and filtrate, whenever the system reached steady state twice a week for 6 months. In all loading rate, BOD5 concentration was less than the standard limit. The removal efficiency of COD in all experiments was up to 80%. Up to 99% of solids, which may mainly include colloidal solids, were removed with micropore MEMBRANE. There was no significant difference between TDS concentration in feed and filtrate. It was concluded that MBR is a versatile technology with high throughput and can treat compost leachate below standard limit if used after appropriate processes.

The objective of this study was to evaluate the feasibility of treating refinery wastewater to meet the applicable discharge limits and agriculture use standard consistently using MEMBRANE BIOREACTOR (MBR) technology to reduce either the environmental impacts of refinery waste water discharge or operational problems of common activated sludge process (ASP). A pilot scale submerged MEMBRANE BIOREACTOR with a MEMBRANE module that consists of 56 flat sheet poly (ether sulfone) (PES) ultra-filter MEMBRANEs was used in this study. The effluent of the dissolved air floatation (DAF) unit from wastewater treatment plant of Tehran refinery was used as a feed. Trials on different MEMBRANE fluxes and hydraulic retention time (HRT) were conducted. The results have shown that the hydraulic retention time of 15.87 (hr) was more applicable. The percentage removal of COD, BOD5, TOC, Oil and grease, TSS, and color was 97.32, 92.58, 96.36, 99.18, 99.99, and 95.58 respectively.The results showed that the quality of the product consistently met the requirement for agriculture use and discharge to the surface water. Due to an increase in mixed liquor suspended solids concentration from 6000 mg/l to 9900 mg/l at the end of experiments, the removal rate was increased from 86.00% at the first stage to 97.32% and 95.22% at the second and third stage respectively. It was concluded that it was feasible to treat the wastewater using SMBR technology.

The MEMBRANE BIOREACTOR technology has been proven to be a single step process in efficient treatment of wastewater, either directly or after pretreatment by reverse osmosis. In this study, a pilot scale experiment was studied to treat a synthetic municipal wastewater sample. The aerobic reactor with a submerged MEMBRANE used in this work was continuously aerated for organic matter oxidation, nitrification and phosphorous uptake as well as for fouling control. The mixed liquor was recycled from the aerated zone to the anoxic zone for denitrification. The MEMBRANE had a nominal pore size of 0.1 μm and a filtration area of 4.0 m2. The performance of submerged MEMBRANE BIOREACTOR was examined in order to determine the removal efficiency of organic compounds and nitrogen in different solid retention times (10, 20, 30, and 40 days) under a continuous inflow of the synthetic municipal wastewater. Results indicated that the submerged MEMBRANE BIOREACTOR could efficiently remove the pollutants. Average removal rates of chemical oxygen demand, total Kejeldahl nitrogen removal, total nitrogen and phosphorous reached to as high as 99.3%, 98.1%, 85.5%, and 52%, respectively. Furthermore, concentrations of nitrate and nitrite in the last stage were well reduced and reached to 5.3 and 0.047 mg/L, respectively.

MEMBRANE technology is one of the few non-pollutant choices when selecting a treatment process. A MEMBRANE with suitable pore size can remove almost all pollutants without using any chemicals. In this research, chromium, zinc and lead were removed from synthetic wastewater by a MEMBRANE BIOREACTOR. The results showed that by using a MEMBRANE BIOREACTOR, the COD removal efficiency was increased in all conditions in comparison with that of an activated sludge process system. According to the test results, in the case of having heavy metals; Chromium with a concentration below 50 mg/l, the removal efficiency was shown to be about 95% and at these concentrations, chromium has no toxic effect on micro-organisms. However, the Activated Sludge Process showed poor removal efficiency in the case of having zinc. But when ASP was used in conjunction with the MEMBRANE, the removal efficiency was increased to 76%. MEMBRANE showed an improvement of efficiency from 44% to 65% in the case of having 50 mg/l of lead.