A process for the thermo-hydraulic control of gas hydrates

摘要

A process for the thermo-hydraulic control of gas hydrates under conditions of gas hydrate formation within a petroleum well by use of a Nitrogen Generation System/Foam, which process comprises: a) viscosifying an aqueous, equimolar solution of ammonium chloride and sodium nitrite having a concentration between 2.0 and 4.5 molar with hydroxyethyl cellulose having a concentration between 0.3 and 1.2 weight/volume maintaining the pH at a value between 8.0 and 8.3; b) adding between 1 and 2% by volume of a solution of acetic acid activator having a concentration of 40 volume % to the aqueous viscosified solution of step a) to obtain a nitrogen gas- and heat-generating foamed and viscosified fluid; c) contacting the nitrogen gas- and heat-generating foamed and viscosified fluid of step b) with the gas hydrate thereby causing the gas hydrate to dissolve as a consequence of the increase in temperature and reduction of pressure; d) recovering spent fluid and separating the aqueous phase.