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Microbial Fuel Cell Amalgamated with Other Existing Technologies for Efficient Power Generation and Simultaneous Wastewater Treatment
Published in Gunjan Mukherjee, Sunny Dhiman, Waste Management, 2023
Sanchita Bipin Patwardhan, Poojhaa Shanmugam, Shriya Jitendra Kalburge, Ayush Singha Roy, Jayesh Sonawne, Ram Prasad, Piyush K. Gupta, Soumya Pandit
One commercially available technology used for the treatment of wastewater is the MBR (membrane bioreactor), which can be combined with the MFC to reduce the cost of energy and develop the superiority of effluent (Gao et al. 2017). These advantages were the reason that many studies were conducted on the MFC-MBR system to check its efficiency and viability. The system born from the assimilation of the advantages of MFC and MBR was named a “bioelectrochemical membrane reactor” (Wang et al. 2009). Though the scheme of this bioreactor was quite complicated, it was capable of reaching an extreme power density of 4.35 W/m3. It also had improved contaminant removal, which was credited to the solid elimination and significant biomass retention (Gao et al. 2017). Another setup was reported which had increased O2 uptake in the aeration tank of the MBR with the use of MFC biocathode. The MBR was mounted in the MFC, where sections of steel mesh membranes acted as both filtration units and cathode. These mesh membranes had the advantage of being simply stripped and washed without affecting the anode chamber (Liu et al. 2011). A different study came up with a similar combination but using commercial cathode membranes (stainless steel) net altered using polypyrrole film treated by 9, 10-anthraquinone-2-sulfonic acid [AQS]. This added to fouling alleviation and the electrocatalytic denaturation of the pollutants via the bioelectricity which is generated (Hegab et al. 2016).
Membrane Bioreactor for Perchlorate Treatment
Published in Amitava Rakshit, Manoj Parihar, Binoy Sarkar, Harikesh B. Singh, Leonardo Fernandes Fraceto, Bioremediation Science From Theory to Practice, 2021
Benny Marie B. Ensano, Sivasankar Annamalai, Yeonghee Ahn
The addition of electron donor to the contaminated water must be carefully controlled as insufficient amount may lead to incomplete perchlorate removal, while over dozing, particularly for organic compounds, can stimulate substantial biomass accumulation in water distribution systems as well as the possible formation of toxic disinfection by-products (Gao et al. 2016). This constitutes one of the major drawbacks of the biological method. In lieu of this, scientists around the world have been searching for new and promising approach to improve the biodegradation process of perchlorate for both in situ and ex situ applications, the latter being more prevalent in practice. One emerging technology is the membrane bioreactor (MBR), which is the combination of membrane technology and biodegradation process. This paper puts an emphasis on the applicability of perchlorate treatment by MBR, its advantages over other treatment methods, limitation for practical implementations and some future challenges.
Physico-chemical treatment processes
Published in Nick F. Gray, Water Science and Technology: An Introduction, 2017
Two reactor designs are used in the activated sludge process (Section 11.1) to replace the post-settlement stage, which separates the final effluent from the microbial biomass, with membranes. External membranes are known as sidestream systems and behave exactly as the clarification step being an external unit (Figure 18.21), while internal or submerged membranes are submerged within the aeration tank (Figure 18.22 and Table 18.5). Membranes made from polymeric materials, such as acrylonitrite, polyethylene or polysulphone, and with a pore size of 0.1–0.4 μm are generally used. The membranes are configured as hollow fibre or flat sheets, ensuring high flow rates per unit area of membrane (i.e. flux) of 0.5–1.0 m3 m2 day−1 at pressures as low as 0.1 bar (104 Pa). Known as membrane bioreactors (MBRs), these systems are very compact as they are operated at high MLSS concentrations (16,000–20,000 mg L−1), with f/m ratios typically 0.02–0.4 and with long sludge ages. The long sludge age ensures maximum endogenous respiration resulting in relatively low sludge production rates of <0.3 kg kg−1 BOD. MBR systems produce very high-quality effluents with BOD <5 mg L−1, suspended solids <2 mg L−1 and a high removal efficiency of pathogens including bacteria and viruses. From an operational perspective, the replacement of the secondary settlement step means that traditional separation problems associated with floc morphology and denitrification (Table 11.3) are no longer relevant.
An insight on the advancements of biological technologies in the bioremediation of textile effluents
Published in Urban Water Journal, 2022
Swarnkumar Reddy, Jabez Osborne
Membrane bioreactors are a recently developed process that is used in wastewater treatment. MBR works on a hybrid process with two independent treatment processes. These bioreactors are the combination of suspended microbial systems and membrane technologies (Xiao et al. 2019; Iorhemen, Hamza, and Tay 2016). The cooperation of traditional ASP and membrane technology offers effective removal of several emerging contaminants that are resistant to ASP. MBRs are significantly effective in the removal of recalcitrant pollutants than activated sludge process and traditionally constructed wetland, this method offers higher removal of contaminants with two strategies: retention of sludge on membrane promotes biofilm formation for the degradation of pollutants and physical separation of larger sized compounds on the membrane Figure 2 (Cecconet et al. 2017; Martin et al. 2011; Frank et al. 2017). MBRs are widely used in various industries including food, paper, textile, and tannery industries. The efficiency of MBRs is highly limited by the presence of anoxic compartments, nature of the effluent, operational temperature, pH, and conductivity of the effluent (Neoh et al. 2016; Rodriguez-Sanchez et al. 2018). Membrane fouling is one of the major limiting factors that could be alleviated by washing or replacing the filters that makes the procedure cost-ineffective (Luo et al. 2017; Petta et al. 2017).
The fate and enhanced removal of polycyclic aromatic hydrocarbons in wastewater and sludge treatment system: A review
Published in Critical Reviews in Environmental Science and Technology, 2019
Xiaoyang Zhang, Tong Yu, Xu Li, Junqin Yao, Weiguo Liu, Shunli Chang, Yinguang Chen
The use of membrane bioreactor (MBR) to treat wastewater, especially industrial wastewater, has several advantages over conventional activated sludge technique, such as low and stable effluent concentration with low space requirement (Grandclement et al., 2017). The removal of PAHs in MBR has been reported by researchers. Fatone et al. (2011) studied three WWTPs operated with MBRs, and found that the removal efficiencies of the total PAHs varied from 19% to 92%. Gonzalez-Perez et al. (2012) investigated the variations of PHE, FLT and PYR in a full experimental MBR treating urban wastewater, and the results showed that all target PAHs had high removal efficiency (around 90%). Yan et al. (2016) combined MBR with coagulants to treat real textile dyeing wastewater, and found similar removal efficiency of the total PAHs, particularly FLU, ACY, FLT, BaA, BaP and IcdP, which could be completely removed. Mozo, Stricot, Lesage, and Spérandio (2011) also found the high removal both in cross-flow and dead-end MBRs.
Long-term MBR performance of polymeric membrane modified with Bismuth-BAL chelate (BisBAL)
Published in Environmental Technology, 2019
Turker Turken, Borte Kose-Mutlu, Selin Okatan, Gamze Durmaz, Mehmet C. Guclu, Serkan Guclu, Suleyman Ovez, Ismail Koyuncu
In the last two decades, Membrane Bioreactor (MBR) technology has exponentially grown because it offers over the conventional treatment processes via its advantages like a smaller footprint, advantageous effluent quality, and better process control. In the late 80’s, the development of submerged membrane technology, which could reduce the energy consumption during MBR operation by using aeration to induce a cross-flow condition and withdrawing purified water by low vacuum, allowed the adoption of MBR technology to other conventional applications [1]. Recent studies on advanced molecular biological techniques have revealed that the characteristics of a biocake formed on the membrane surface like porosity and bio-volume are closely associated with the permeability loss, which can be called as membrane biofouling in MBRs. One of the most important and common techniques is using additives in order to produce antibacterial membrane for biofouling prevention [2].