Wastewater treatment using adsorption process in column for agricultural purposes

Abstract Water is essential for life, important for the ecosystem and it is in great demand due to its scarcity. This study explored the reuse of the wastewater of the Water Treatment Plant in Gramame for agricultural purposes. A qualitative and quantitative investigation of the effluent was carried out through the characterization of its physical and chemical parameters, comparing the results to what is allowed by the current legislation, CONAMA Resolution 357/2005. After this process, the activated charcoal of coco-da-baia mesocarp, adsorbent material, was prepared and tested in a filter system in a column with a continuous flow and ascendant entrance, in which the kinetic effect was evaluated. This technique was evaluated by correlating the reduced values in the adsorption material, respecting the initial effluent concentration, obtaining a reduction of 50% in the hardness, 87.5% in chloride and 66.6% in acidity. These results verified the adequacy of the technique in potential hydrogenation (pH) and abrupt reduction of color and turbidity. This treatment is suggested to qualify the effluent for use in agricultural, safe for humans and the environment. The adsorbent substrate efficiency was verified by correlating it with the Thomas isothermal model.摘要 水是生命赖以生存的基础，对生态系统至关重要，且因其稀缺性而需求缺口巨大。本研究针对格拉马梅（Gramame）污水处理厂的废水，探索其农业回用的可行性。通过对出水的物理化学参数开展表征分析，本研究完成了定性与定量检测，并将检测结果与现行法规——巴西国家环境委员会（CONAMA）第357/2005号决议的允许限值进行比对。随后，本研究制备了巴伊亚椰（coco-da-baia）中果皮活性炭作为吸附材料，并在带有上进料口的连续流柱式过滤系统中开展测试，对其动力学效应进行评估。本研究通过关联吸附材料的去除率与原废水初始浓度对该处理技术进行性能评估，结果显示：硬度去除率达50%，氯化物去除率达87.5%，酸度去除率达66.6%。上述结果验证了该技术在pH值调控以及色度与浊度大幅降低方面的适用性。本研究建议采用该处理工艺，使废水达到农业回用标准，保障人体健康与生态环境安全。通过与托马斯（Thomas）等温吸附模型进行关联分析，验证了该吸附基质的处理效能。