Improved Paraffin-Deposition-Profile Estimation in Hydrocarbon Pipelines and Effective Mitigation Review

Abstract

Flow of paraffinic hydrocarbon liquids within extended pipeline networks or wells, where the environment/bulk temperature is below the cloud point or wax-appearance temperature (WAT), could result in precipitation of wax from the bulk fluid. Precipitated wax crystals from crudes deposits on the inner pipe wall could lead to reduced flow area or even complete blockage and could present a costly problem in the production and transportation of petroleum products. Timely removal of such deposits is extremely important to avoid associated problems. This paper illustrates a numerical approach to estimate the deposition profile and its effect on flow-related parameters. Later, the procedure is validated with field data from a North Sea offshore production facility. This paper also seeks to propose a feasible solution to avoid such flow-assurance issues; in doing so, current commonly practiced reduction and preventive methods are reviewed. Previously, providing thermal insulation with aerogel foam had proved to be the most effective option in preventing wax from precipitating. A relatively new approach is discussed in this paper, which allows for minimizing the usage of insulation material in an attempt to reduce the implementation cost of the proposed precaution. Theoretical implementation of the procedure was also conducted to identify its effectiveness, which was later found to be elimination of the deposition completely.

Application of Flue Gas Foam-Assisted Steam Flooding in Complex and Difficult-to-Produce Heavy Oil Reservoirs

“…This indicates that foam injection is conducive to controlling gas mobility and reducing gas production rate. In addition, due to the presence of foam, the gas is trapped in the foam, which increases gas retention. − …”

“…In addition, due to the presence of foam, the gas is trapped in the foam, which increases gas retention. 34 − 37 …”

Experimental study on flue gas foam-assisted steam flooding: investigating characteristics of enhanced oil recovery and gas storage

“…At this time, the number of foams entering the model should be consistent with the number of output theoretically, and the pressure difference curve fluctuates around a certain equilibrium value. Due to the high viscosity between molecules of heavy oil, a small amount of gas cannot break through and is wrapped in heavy oil to form the state of foam oil and then produced together, indicating that gas is not completely separated from oil and flows, and some of it miscibles into heavy oil molecules, which plays a certain role in improving the fluidity of oil (JPT staff, 2006;Bybee, 2010;Sheikh Mohammad Samiur and Chacko, 2013;Singh, 2014;Karatum et al, 2016). Therefore, it can be inferred that the existence states of flue gas in the model may include such as flue gas locked by foam liquid film, flue gas dissolved in heavy oil and single-phase free gas.…”