Laboratory evaluation of caricaceae plant as a locally sourced surfactant for gas hydrate inhibition in a laboratory mini flow loop

Abstract

The oil and gas business is serious business and involves millions of dollars so whatever mitigates flow assurance is taken seriously. One of such things is natural gas hydrates. Hydrates are crystalline solids formed when water under low temperatures and high pressures encapsulated natural gases (C₁–C₄). They form blockages and impede the flow of gas which can lead to the loss of millions of dollars and at times lead to personnel death. Mitigation of gas hydrates has always been with chemicals especially for areas like deep offshore where accessibility is difficult. The chemicals that are in use currently are generally synthetic, expensive and hazardous to lives and environment hence the need for readily available locally sourced materials that are eco-friendly. This study considers and screens a locally sourced surfactant from the plant family caricaceae’ Extract (CE) as a gas hydrate inhibitor in a locally fabricated 39.4-inch mini flow loop of ½ inch internal diameter (ID) which mimics the offshore environment. Various pressure plots (pressure versus time, initial and final pressure versus time and change in pressure versus time) show that the CE performed better than MEG with percentage volumes of gas left in the system for 0.01–0.05 wt% of the extract having values that ranged from 76.7 to 87.33, while volume left for MEG ranged between 70 and 74.67% (1–5 wt%). The CE performed better in small doses compared to those of MEG, in all weight percentages of study. Furthermore, the inhibition capacities which show the level of performance of the inhibitors was also used as a measure of inhibition for both inhibitors. The CE inhibited systems had values of 69.3, 80.7, 78.07, 79.82, and 83.3%, while that of the MEG inhibited system was 60.53, 55.26, 73.68, 72.81, and 66.67% for the various weight percentages considered. The CE should be developed as gas hydrate inhibitors due to its effectiveness and eco-friendliness.