Study on the Effect of Feed Conditions towards Temperature Drop in the Joule Thomson Valve for Natural Gas Dehydration

In the oil and gas industry, the presence of water vapor and carbon dioxide has brought over much inconvenience to natural gas processing and transportation. Many technologies have been invented and applied to tackle this problem. The most common technologies that are being used for the dehydration of natural gas are absorption and adsorption. Common absorption material used are triethylene glycol (TEG) while common adsorption material used are silica gel and molecular sieve. By using the absorption and adsorption technique, large amount of moisture from the natural gas could be removed. This technology has been used in the industry for decades due to its promising efficiency. However, the packing column requires a large column space for maximizing the absorption amount. Next, high energy is needed for the regeneration of solid and liquid desiccants. Furthermore, the desiccant is exposed to the risk of poisoning when it is being exposed to heavy hydrocarbon and other gasses in the natural gas. Hence, a new method is being studied and the Joule Thomson Expansion throttling technique is proposed to remove the water vapor from natural gas and carbon dioxide mixture. The benefits of the proposed technique includes self- induced refrigeration, low operating cost, and simple mechanical design. In this project, the effect of feed conditions towards the temperature change in the Joule Thomson valve is investigated. The temperature change of the natural gas is important as condensation of water would happen providing that the temperature change is large enough. By achieving the dew point of the gas mixture, condensation process would occur. The investigation will be carried out using different feed pressure and different composition of gas mixtures. In addition, the simulation of the project is developed in HYSYS software built by AspenTech. The calculated value from the simulation is compared with the experimental data to study on the contributing factors towards the temperature change of the gas mixture. With the known temperature change, a further study could be carried out on the percent of water removal attainable.