Abstract

Large volumes of produced water are generated as a byproduct in activities of oil and gas exploitation, which can be reused in agriculture after a treatment process. Activated sludge treatment has been successfully used to remove oil from wastewater, but systematic studies on the toxicity of this effluent using this treatment are scarce in the literature. In this study, it was investigated the performance of an activated sludge system in the treatment of a synthetic produced water under different initial conditions in terms of salinity and oil and grease concentration. Furthermore, it was evaluated this effluent phytotoxicity in the germination, and seedling and plant growths of sunflower and corn seeds using untreated and treated synthetic produced water. Results revealed the activated sludge effectiveness in oil and grease and salinity removal from produced water, viz. high removal efficiency of 99.01 ± 0.28 and 91.07 ± 0.39%., respectively. Untreated produced water showed considerable toxic effects on the germination (74.67 ± 2.31% and 82.67 ± 2.31 for sunflower and corn seeds, respectively) and growth stages of sunflower and corn seed plants. The germination percentage was approximately 100% for both types of seed. The seedling and plant growth of the two seeds irrigated with treated produced water had similar performance when used tap water. These results highlighted the potential reuse as an unconventional water resource for plant irrigation of the synthetic produced water treated by an activated sludge process, which technology has showed high removal performance of salinity and oil.

摘要

在石油和天然气开采活动中会产生大量副产水，这些副产品经过处理后可以在农业中重复使用。活性污泥处理已被成功地用于去除废水中的油，但是使用这种处理方法对该废水的毒性进行系统的研究在文献中很少。在这项研究中，研究了活性污泥系统在不同初始条件下在盐度和油脂浓度方面在处理合成采出水方面的性能。此外，使用未经处理和处理过的合成采出水，评估了这种发芽中的植物毒性以及向日葵和玉米种子的幼苗和植物生长。结果表明，活性污泥在油脂中的有效性以及从采出水中的盐分去除，即。高去除效率分别为99.01±0.28和91.07±0.39％。未经处理的采出水对向日葵和玉米种子的发芽（向日葵和玉米种子分别为74.67±2.31％和82.67±2.31）和相当大的毒性作用。两种种子的发芽率约为100％。用自来水灌溉的两种种子的幼苗和植物生长具有相似的性能。这些结果突出表明，通过活性污泥工艺处理的合成采出水可作为非常规水资源用于植物灌溉，该技术已显示出较高的盐分和油脂去除性能。