The Advancement in Membrane Bioreactor (MBR) Technology toward Sustainable Industrial Wastewater Management

Abstract

The advancement in water treatment technology has revolutionized the progress of membrane bioreactor (MBR) technology in the modern era. The large space requirement, low efficiency, and high cost of the traditional activated sludge process have given the necessary space for the MBR system to come into action. The conventional activated sludge (CAS) process and tertiary filtration can be replaced by immersed and side-stream MBR. This article outlines the historical advancement of the MBR process in the treatment of industrial and municipal wastewaters. The structural features and design parameters of MBR, e.g., membrane surface properties, permeate flux, retention time, pH, alkalinity, temperature, cleaning frequency, etc., highly influence the efficiency of the MBR process. The submerged MBR can handle lower permeate flux (requires less power), whereas the side-stream MBR can handle higher permeate flux (requires more power). However, MBR has some operational issues with conventional water treatment technologies. The quality of sludge, equipment requirements, and fouling are major drawbacks of the MBR process. This review paper also deals with the approach to address these constraints. However, given the energy limitations, climatic changes, and resource depletion, conventional wastewater treatment systems face significant obstacles. When compared with CAS, MBR has better permeate quality, simpler operational management, and a reduced footprint requirement. Thus, for sustainable water treatment, MBR can be an efficient tool.

Biochemical Characteristics of Laccases and their Practical Application in the Removal of Xenobiotics from Waters

“…The enzyme, as well as the structure, physicochemical properties and size of the expected biodegradation products affect the choice of the bioreactor membrane. Therefore, it is important to know the membrane characteristics, such as pore size, material, properties, presence of functional groups, hydrophilicity and surface charge [273,312,313]. A large surface area for enzyme attachment and good porosity and spatial structure are sought-after properties of good membrane support.…”

Utilizing ultrasonic vibrations to mitigate membrane fouling in domestic wastewater membrane bioreactors: a mini review

“…[6][7][8][9][10] Fouling arises from the deposition and accumulation of various dissolved and suspended constituents, including microbial cells, extracellular polymeric substances (EPS), colloidal particles and soluble microbial products (SMP) on the membrane surface and pores. 10,[14][15][16][17][18] Particulate fouling does not occur suddenly; instead, it is gradual. Fouling begins with the blocking of pores, where the deposition of particles near the opening limits the pore entrance.…”

“…Fouling begins with the blocking of pores, where the deposition of particles near the opening limits the pore entrance. 3,[13][14][15][16][17] Over time, this layer enhances due to the accumulation of additional particles, leading to complete pore blockage. In the second stage a thick cake layer forms, significantly affecting the membrane's efficiency and selectivity.…”

“…[7][8][9][10][11] However, a significant obstacle preventing their widespread integration is membrane fouling. 3,[5][6][7][8][11][12][13][14] Membrane fouling occurs when suspended or dissolved substances accumulate on the surface of the membrane or within the membrane's pores. [6][7][8] This accumulation significantly decreases the efficiency of MBRs, leading to a decrease in permeate flux, a significant increase in the transmembrane pressure (TPR), [15][16][17][18][19] reduced effluent quality and a shortened membrane lifetime.…”

“…MBRs are based on combining biodegradation with membrane separation, allowing these reactors to handle high organic and inorganic loadings compared to conventional systems and making them suitable for treating domestic and industrial wastewater 7‐11 . However, a significant obstacle preventing their widespread integration is membrane fouling 3,5‐8,11‐14 …”