Compound Cleaning Agent for Oily Sludge from Experiments and Molecular Simulations

Lixin Wei; Yang Song; Kun Tong; Shiling Yuan; Shuixiang Xie; Lijun Shi; Xinlei Jia; Xiaoheng Geng; Haiying Guo

doi:10.1021/acsomega.1c02286

Compound Cleaning Agent for Oily Sludge from Experiments and Molecular Simulations

ACS Omega. 2021 Dec 3;6(49):33300-33309. doi: 10.1021/acsomega.1c02286. eCollection 2021 Dec 14.

Authors

Lixin Wei^{1

2

3}, Yang Song³, Kun Tong^{1

2}, Shiling Yuan^{1

2

4}, Shuixiang Xie^{1

2}, Lijun Shi³, Xinlei Jia^{3

5}, Xiaoheng Geng^{1

2

5}, Haiying Guo^{1

2

5}

Affiliations

¹ State Key Laboratory of Petroleum Pollution Control, CNPC Research Institute of Safety & Environment Technology, Beijing 100000, China.
² Department of Environment Technology, CNPC Research Institute of Safety & Environment Technology, Beijing 100000, China.
³ School of Petroleum Engineering, Northeast Petroleum University, Daqing 163318, China.
⁴ School of Chemistry and Chemical Engineering, Shandong University, Jinan 250013, China.
⁵ College of Chemical Engineering and Safety, Binzhou University, Binzhou 256600, China.

Abstract

This paper reported a new oily sludge compound cleaning agent formula, which used a combination of molecular simulation and experimental methods to study its interfacial formation energy (IFE), and exciting results were obtained. From a total of 24 surfactants in five categories, sodium silicate (Na₂SiO₃), sodium dodecylbenzene sulfonate, and fatty alcohol polyoxyethylene polyoxypropylene ether (JFC-SF) were screened out because of their excellent washing oil effect. Under a reasonable orthogonal system, when the mass ratio of the three surfactants was 3:1:1, the oil desorption effect was the best, the oil residual rate could reach 2.13%, and the oil removal efficiency could reach 93.53%. Verified by the molecular dynamics simulation module, the absolute value of the interface binding energy was the largest at this compound ratio, which was 465.71 kcal/mol. More importantly, we have discussed in depth the mechanism of adsorption and permeation of oily sludge by cleaning agents. Through single-factor influence experiments, the following optimized working condition parameters of the cleaning agent were determined: cleaning conditions with an agent content of 4%, a temperature of 70 °C, a stirring speed of 400 rpm, a cleaning time of 30 min, and a liquid-solid ratio (L/S) of 4:1. The research results laid the foundation for resource utilization, harmlessness, and reduction of oily sludge in the Liaohe oilfield.