Author(s)

Likang Zhao ¹, Haiquan Zhong ¹, Guoxin Liu ², Chuangen Zheng ¹, Jian Yang ¹, Xiaoyi Dong ¹

Affiliation(s)

¹ State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu, 610500, China
² CCDC Sulige Project Managment Department, Erdos, Inner Mongolia, 017000, China

Corresponding Author

Haiquan Zhong

ABSTRACT

Wax formation in oil and gas wells can limit the recovery rate of the well and can lead to well shutdown in severe cases. It is therefore important to predict the deposition of waxe during oil and gas production. In order to study the deposition pattern of wax in the wellbore, the wellbore flow and heat transfer processes were analysed, and a method for predicting the wellbore flow, temperature, and pressure was developed and coupled to the pressure and temperature. By analysing the thermodynamic equilibrium conditions of the system, the point of wax precipitation is determined based on the change in phase state of the system. A new simplified wax deposition prediction model incorporating diffusion, shear deposition, and the effects of ageing and stripping was developed by writing a program based on Fick's diffusion theory. A sensitivity analysis of wax deposition revealed that the thickness of wax formation increases as the production time gets longer, decreases as water content and fluid production increases, and the depth of the wax formation point becomes shallower, while the variable of dissolved oil to gas ratio has little effect on wellbore wax formation. 

KEYWORDS

Well Wax Formation, Pressure-Temperature Coupled Model, Thermodynamic Model, Wax Deposition Model

CITE THIS PAPER

Likang Zhao, Haiquan Zhong, Guoxin Liu, Chuangen Zheng, Jian Yang, Xiaoyi Dong, Prediction and Simulation of Wax Deposition in Oil and Gas Wells. Environment, Resource and Ecology Journal (2023) Vol. 7: 69-78. DOI: http://dx.doi.org/10.23977/erej.2023.070110.

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