Prediction and Prevention of Wax Deposition in MERO-006T: A Thermodynamic Modelling Approach

Abstract

MERO-006T is an oil development well that was drilled and completed in the Q2100X reservoir. The well came into production in March 1988 and has been plagued with incessant wax build up leading to loss of oil production several times over a period of 17years. Several wax cutting activities have been carried out to restore production in the well, however due to the frequency of wax build up leading to loss of revenue and the difficulty of the swamp terrain where the well is located, it became pertinent to adopt a more optimal, cost effective and long-term approach to address the frequent deferment caused by wax build up. Research indicates that a wax inhibition tool (Silver HAWG) can be deployed in the well to address wax build up issue though historical deployment in some wells have not been very effective due to suboptimal installation depths in these wells. Hence, it became pertinent to determine the optimal depth for installation of the wax inhibition tool in MERO-006T. This paper highlights the thermodynamic modelling approach adopted to determine the Wax Appearance Temperature in MERO-006T, the well modelling approach to estimate the depth which wax formation would occur and the optimal depth to place the wax inhibition tool based on lifecycle production expectations from the well. Installation of the Silver HAWG is expected to restore ca. 500 bopd, improve well availability by 30% and avoid biannual costs of ca. $2mln associated with repeated wax treatment in the well.