Laboratory of Bioremediation and Metagenomics Research (LBMR), Department of Environmental Microbiology (DEM), Babasaheb Bhimrao Ambedkar University, Vidya Vihar, Raebareli Road, Lucknow, 226 025, U.P., India.
University Centre of Research and Development, Department of Chemistry, Chandigarh University, Gharuan, Mohali, 140413, Panjab, India.
Chemosphere. 2023 Sep;336:139192. doi: 10.1016/j.chemosphere.2023.139192. Epub 2023 Jun 21.
Tannery wastewater (TWW) has high BOD, COD, TS and variety of pollutants like chromium, formaldehydes, biocides, oils, chlorophenols, detergents and phthalates etc. Besides these pollutants, TWW also rich source of nutrients like nitrogen, phosphorus, carbon and sulphur etc. that can be utilized by microalgae during their growth. Direct disposal of TWW into the environment may lead severe environmental and health threats, therefore it needs to be treated adequately. Microalgae are considered as an efficient microorganisms (fast growing, adaptability and strain robustness, high surface to volume ratio, energy saving) for remediation of wastewaters with simultaneous biomass recovery and generation of value-added products (VAPs) such as biofuels, biohydrogen, biopolymer, biofertilizer, pigments, bioethanol, bioactive compounds, nutraceutical etc. Most microalgae are photosynthetic and use CO and light energy to synthesise carbohydrate and reduces the emission of greenhouse gasses. Microalgae are also reported to remove heavy metals and antibiotics from wastewaters by bioaccumulation, biodegradation and biosorption. Microalgal treatment can be an alternative of conventional processes with generation of VAPs. The use of biotechnology in wastewater remediation with simultaneous generation of VAPs is trending. The validation of economic viability and environmental sustainability, life cycle assessment studies and techno-economic analysis is undergoing. Thus, in this review, the characteristics of TWW and microalgae are summarized, which manifest microalgae as potential candidates for wastewater remediation with simultaneous production of VAPs. Further, the treatment mechanisms, various factors (physical, chemical, mechanical and biological etc.) affecting treatment efficiency as well as challenges associated with microalgal remediation are also discussed.
制革废水（TWW）具有高 BOD、COD、TS 和多种污染物，如铬、甲醛、杀生剂、油、氯酚、洗涤剂和邻苯二甲酸酯等。除了这些污染物，TWW 还富含氮、磷、碳和硫等营养物质，这些物质可以被微藻在生长过程中利用。直接将 TWW 排放到环境中可能会导致严重的环境和健康威胁，因此需要进行充分处理。微藻被认为是一种有效的微生物（生长迅速、适应性强、菌株健壮、高表面积与体积比、节能），可用于修复废水，同时回收生物质并产生增值产品（VAPs），如生物燃料、生物氢、生物聚合物、生物肥料、色素、生物乙醇、生物活性化合物、营养保健品等。大多数微藻是光合作用的，它们利用 CO 和光能合成碳水化合物，并减少温室气体的排放。微藻还被报道可通过生物积累、生物降解和生物吸附从废水中去除重金属和抗生素。微藻处理可以替代传统工艺，同时产生 VAPs。利用生物技术进行废水修复并同时产生 VAPs 的趋势正在上升。正在进行经济可行性和环境可持续性的验证、生命周期评估研究和技术经济分析。因此，在本综述中，总结了 TWW 和微藻的特点，表明微藻是废水修复同时生产 VAPs 的潜在候选物。此外，还讨论了处理机制、影响处理效率的各种因素（物理、化学、机械和生物等）以及与微藻修复相关的挑战。
