Husain Atif, Ayub Sohail, Khan Afzal Husain, Alam Shah Saud, Hasan Mohd Abul
Department of Civil Engineering, Aligarh Muslim University, Aligarh, India.
Civil and Architectural Engineering Department, College of Engineering and Computer Sciences, Jazan University, Jazan, 45142, Saudi Arabia.
J Environ Manage. 2025 Sep;391:126502. doi: 10.1016/j.jenvman.2025.126502. Epub 2025 Jul 12.
This study investigated the sustainable approach to removing and recovering chromium by chemical precipitation using sodium hydroxide (NaOH) and sulfuric acid (HSO). The raw tannery wastewater was studied under varying pH and agitation speed to assess and optimize the process variables using an atomic absorption spectrometer, exhibiting promising removal and recovery rates. The highest chromium removal efficiency of 96.9 % was obtained at a pH of 10.0 with an agitation speed of 500 rpm, while the maximum recovery efficiency of 83.4 % was achieved at pH 2.8 under similar conditions. The life cycle environmental impacts were also assessed for 10 different indicator categories, including particulate matter (PMFP), stratospheric ozone depletion (ODP), human damage ozone formation (HOFP), ecosystem damage ozone formation (EOFP), terrestrial acidification potential (AP), marine eutrophication (ME), global warming potential (GWP), mineral resource scarcity (MRS), water consumption (WC), and fossil resource scarcity (FRS). The scope of the LCA study is to estimate the energy consumption and environmental burden of recovery of chromium from tannery wastewater and evaluate whether the proposed method is environmentally justifiable. Environmental impacts associated with 1 Kg of recovered chromium were utilized as the functional unit for this study to correlate the inputs and outputs of the process using GREET.net v2022 software. Furthermore, the cost analysis showed that chromium recovery could generate an estimated net profit of 588,248 USD/year, confirming the economic viability of the process. This research offers significant insights into improving chromium recovery efficiency while reducing environmental and economic costs, presenting a scalable solution for industrial wastewater treatment.
本研究调查了使用氢氧化钠（NaOH）和硫酸（HSO）通过化学沉淀去除和回收铬的可持续方法。在不同的pH值和搅拌速度下对制革厂原废水进行了研究，以使用原子吸收光谱仪评估和优化工艺变量，显示出有前景的去除和回收率。在pH值为10.0、搅拌速度为500转/分钟时，铬的去除效率最高，为96.9%；而在类似条件下，pH值为2.8时，回收率最高，为83.4%。还对10种不同的指标类别进行了生命周期环境影响评估，包括颗粒物（PMFP）、平流层臭氧消耗（ODP）、人类损害臭氧形成（HOFP）、生态系统损害臭氧形成（EOFP）、陆地酸化潜力（AP）、海洋富营养化（ME）、全球变暖潜力（GWP）、矿产资源稀缺（MRS）、水资源消耗（WC）和化石资源稀缺（FRS）。生命周期评估（LCA）研究的范围是估计从制革厂废水中回收铬的能源消耗和环境负担，并评估所提出的方法在环境方面是否合理。本研究将与1千克回收铬相关的环境影响用作功能单位，以使用GREET.net v2022软件关联该过程的输入和输出。此外，成本分析表明，铬回收每年可产生估计净利润588,248美元，证实了该过程的经济可行性。这项研究为提高铬回收效率同时降低环境和经济成本提供了重要见解，为工业废水处理提供了一种可扩展的解决方案。
