Methanol inhibition and CO2 injection effects on hydrate phase equilibria: Experimental and modeling investigation

One of the main problems that occurs in the gas reservoirs is related to the hydrate formation while producing from a well, either in production strings or lines. Effective parameters which lead to hydrate formations are: high pressure in strings, low wellhead temperature together with water presence; and hence, the high possibility of having this phenomenon in the reservoirs is quite obvious for the gas wells. Hydrate formation in production lines and facilities will also lead to different impediments such as: complete or partial closure in production lines and heat exchangers, erosion of the equipment, pressure reduction, and etc. In this research, the conditions of hydrate formation, using the experimental data from one the Iranian sour gas field have been investigated. In addition, the inhibition effect of methanol on the hydrate-forming conditions has been explored. Finally, the experimental data have been compared with model and the effect of CO2 injection on hydrate phase diagram was evaluated using the presented model.