Dagar Sumit, Singh Santosh Kumar, Gupta Manoj Kumar
Department of Environmental Engineering, Delhi Technological University, New Delhi 110042, India.
Environmental Management Division, Central Pulp and Paper Research Institute, Saharanpur 247001, India.
Membranes (Basel). 2023 Feb 6;13(2):199. doi: 10.3390/membranes13020199.
This recent study aims to evaluate the efficacy of membrane filtration on recovery of water resource from agro-waste such as bagasse, crop-based pulp and paper mill waste. A mini pilot scale membrane system having a combination of pre-treatment filter unit (pre-filter, sediment filter and pre-carbon filter), ultra-filtration and reverse osmosis with spiral wound configuration were employed to evaluate the water reuse efficacy of effluent coming from the secondary clarifier of the conventional treatment plant of the mill. The operational conditions were optimized using Taguchi method at pH 8, temperature 32 °C, and pressure 2 bar and a flow rate of 60 l/hr. The qualities of the effluent from the secondary clarifier, and the permeate from both the combination, viz. Combination 1 (pre-treatment + ultra-filtration) and Combination 2 (pre-treatment + ultra-filtration+ reverse osmosis) were analyzed and the percentage reduction in pH, TDS, TSS, BOD, COD, Color, Lignin, Potassium and Sodium were calculated. The elimination of TDS, COD and BOD with Combination 1 was not promising (<22%). However, the installation of a RO membrane greatly reduced (>88%) the contaminants in both paper mill effluents. The obtained qualities of water from all the combinations were compared with the tolerance standard for reuse as process water. The quality of effluent from the secondary clarifier did not agree with any class of water quality. The permeate from the combination of pre-treatment and UF sufficiently reduced the TSS to reach the requirement. However, the combination of (pre-treatment + UF + RO) adequately complied with the quality standard required for reuse in the making of all grades of paper.
这项最新研究旨在评估膜过滤技术从甘蔗渣、农作物制浆造纸厂废料等农业废弃物中回收水资源的效果。采用了一个小型中试规模的膜系统，该系统结合了预处理过滤单元（预过滤器、沉淀过滤器和预碳过滤器）、超滤和螺旋缠绕式反渗透，用于评估造纸厂传统处理厂二次沉淀池流出的废水的中水回用效果。使用田口方法在pH值为8、温度为32℃、压力为2巴、流速为60升/小时的条件下对操作条件进行了优化。分析了二次沉淀池流出的废水以及两种组合（即组合1：预处理+超滤；组合2：预处理+超滤+反渗透）的渗透液的水质，并计算了pH值、总溶解固体（TDS）、总悬浮固体（TSS）、生化需氧量（BOD）、化学需氧量（COD）、颜色、木质素、钾和钠的去除百分比。组合1对TDS、COD和BOD的去除效果不佳（<22%）。然而，安装反渗透膜大大降低了（>88%）造纸厂两种废水中的污染物。将所有组合得到的水质与作为工艺用水回用的耐受标准进行了比较。二次沉淀池流出的废水水质不符合任何一类水质标准。预处理和超滤组合的渗透液充分降低了TSS，达到了要求。然而，（预处理+超滤+反渗透）组合完全符合所有等级纸张生产中回用所需的质量标准。
