Study on Pollution Characteristics of Shale Refinery Wastewater Fu Yuting, Li Changbo, Zhao Guozheng, Liang Hui, Wang Shuo and Xu Hongzhu E3S Web Conf., 233 (2021) 01146 Published online: 27 January 2021 DOI: 10.1051/e3sconf/202123301146