A Mini Review of the Techno-environmental Sustainability of Biological Processes for the Treatment of High Organic Content Industrial Wastewater Streams

Abstract

Industrial wastewater contains complex and slowly biodegradable compounds often ineffectively treated by conventional activated sludge (CAS) systems. Alternatively, advanced anaerobic technologies are implemented. The current study reviews different potential anaerobic schemes, factors influencing their final performance and optimum combinations of operational/design parameters. Anaerobic membrane bioreactors, upflow anaerobic sludge blanket reactors, expanded granular sludge beds, anaerobic hybrid reactors and inverse fluidized bed reactors are discussed. Their major advantages include: low energy requirements, energy recovery through biogas generation and high organic load removal. pH~7, operation in a mesophilic environment and a hydraulic retention time long enough to enable anaerobic digestion in economically accepted reactor volumes are conditions that optimize the performance of anaerobic configurations. The evaluation additionally considers environmental aspects. The life cycle assessment of anaerobic industrial wastewater treatment reveals its positive environmental effect in terms of greenhouse gases emissions. Methane (a greenhouse gas) primarily contained in the biogas, despite being produced during anaerobic digestion, is utilized for energy production (heating, electricity) instead of being emitted to the atmosphere. Finally, anaerobic wastewater treatment is analyzed as part of the European Commission Innovation Deal that aims at converting conventional wastewater treatment plants to water resource recovery facilities able to combine sustainable wastewater treatment and water reuse. Response to Reviewers: Reviewer #1: The topic and the results of the current study are generally very

Treatment of Palm Oil Mill Effluent Using Membrane Bioreactor: Novel Processes and Their Major Drawbacks

“…Therefore, the rate of biogas (CH 4 ) production may significantly reduce because of the inactive methanogen bacteria at such low pH [44]. In addition, at a prolonging thermophilic condition, the flocs can easily disintegrate to form small particles sizes with varied ranges [232]. Subsequently, the generated particles easily initiate pore blockage, then afterwards develops into a dense cake layer on the membrane surface [232].…”

“…In addition, at a prolonging thermophilic condition, the flocs can easily disintegrate to form small particles sizes with varied ranges [232]. Subsequently, the generated particles easily initiate pore blockage, then afterwards develops into a dense cake layer on the membrane surface [232]. In this manner, it can be said that the mesophilic condition is more favourable to the physiological process of the microbes [208].…”

“…In this manner, it can be said that the mesophilic condition is more favourable to the physiological process of the microbes [208]. This is because at a higher temperature (> 55 • C) the metabolism of the microorganism is negatively denatured, thereby, retarding the rate of microbial activities [191,232]. Based on this note, efforts have been vetted by researchers to identify the optimal effects of temperature on MBR.…”

Enhancing Biochemical Methane Potential and Enrichment of Specific Electroactive Communities from Nixtamalization Wastewater using Granular Activated Carbon as a Conductive Material

“…This wide range is a result of the proportions of water corn and lime that vary in different nixtamal plants [4,5,7]. Its organic matter content makes nejayote a suitable waste for anaerobic digestion process rather than any aerobic process due to the huge amount of energy that is required to degrade its high organic load [8][9][10]. A biochemical methane potential (BMP) test is the most efficient means of identifying the methane production capacity, in anaerobic digestion, for any organic waste [11][12][13].…”

Determinação Da Produção De Biogás Em Uma Fábrica De Chocolates Para Fins De Aproveitamento Energético

“…Em geral, os efluentes das fábricas de chocolates e derivados contêm altas concentrações de matéria orgânica facilmente biodegradável, com o teor de Demanda Química de Oxigênio (DQO) variando entre 2500 e 5400 mg/L e Demanda Bioquímica de Oxigênio (DBO) entre 1840 e 4910 mg/L (BEAL; RAMAN, 2000;DIWANI et al, 2000;ERSAHIN et al, 2011). Estes efluentes não contêm ingredientes tóxicos, mas possuem alto teor de sólidos totais (ST), além dos valores elevados de DQO e DBO (COPETTI et al, 2013), já mencionados anteriormente, que podem ser tratados por sistemas de lodos ativados convencionais (MASSARA et al, 2017).…”