Mesquita Patrícia da Luz, Souza Cássia Ribeiro, Santos Nilza Tatiane G, Rocha Sônia Denise Ferreira
a Mining Engineering Department , Universidade Federal de Minas Gerais , Pampulha, Belo Horizonte , Brazil.
b Chemical Engineering Department , Universidade Federal de São João del-Rei - Campus Alto Paraopeba , Fazenda do Cadete, Ouro Branco , MG , Brazil.
Environ Technol. 2018 Jun;39(12):1544-1556. doi: 10.1080/09593330.2017.1332691. Epub 2017 Jun 5.
Water reuse in industrial processes has been an increasing need encouraged in recent years. However, as the streams are recycled, solutes accumulate, thus requiring purification techniques. Membrane processes (reverse osmosis and electrodialysis) have been implemented and in order to increase the reuse of water at its highest level, crystallization has been evaluated to remove salts from the concentrate produced and get a feasible disposal. Nevertheless, contaminants affect the crystallization performance, thus making the removal of residual organics important for both the efficiency of crystallization and the increase of water reuse. In this context, aiming at establishing a sustainable virtuous circle, bone char (0.5-1.4 mm particle size, mesoporous structure) was used to remove refractory organics from an electrodialysis concentrate effluent (C-EDR) from a Brazilian petroleum refinery, at a lab-scale, in a fixed-bed adsorption column. Bone char selectively and partially removed the refractory organics, a complex mixture of long-chain hydrocarbons, aromatic compounds, carboxylic acids, amines and amides. The maximum adsorption capacity increased with the increase in bed depth and reduction in flow rate. A maximum removal of 35.60 mg g was achieved for the highest bed depth evaluated (12.9 cm). The breakthrough curves indicated that bone char could adsorb part of the organic compounds from the C-EDR. The scaling up was possible for the C/C ratios of 0.55, 0.60 and 0.65, providing a service time at about 16 days for 45% removal efficiency for typical real operational conditions used in the refinery.
近年来，工业生产过程中的水回用需求日益增长。然而，随着水流的循环利用，溶质会不断积累，因此需要采用净化技术。膜工艺（反渗透和电渗析）已得到应用，为了最大程度地提高水的回用率，人们对结晶法进行了评估，以从产生的浓缩液中去除盐分并实现可行的处置。然而，污染物会影响结晶性能，因此去除残留有机物对于提高结晶效率和增加水回用率都很重要。在此背景下，为建立可持续的良性循环，采用了粒度为0.5 - 1.4毫米、具有介孔结构的骨炭，在实验室规模的固定床吸附柱中，去除巴西一家炼油厂电渗析浓缩液流出物（C - EDR）中的难降解有机物。骨炭选择性地部分去除了难降解有机物，这些有机物是长链烃、芳香族化合物、羧酸、胺和酰胺的复杂混合物。最大吸附容量随床层深度的增加和流速的降低而增大。在所评估的最高床层深度（12.9厘米）下，最大去除量达到35.60毫克/克。穿透曲线表明骨炭可以从C - EDR中吸附部分有机化合物。对于C/C比为0.55、0.60和0.65的情况，可以进行放大，在炼油厂典型的实际运行条件下，去除效率为45%时，可提供约16天的服务时间。
