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Objectives The aim is to solve the problems of low dehydration efficiency and high energy consumption in triethylene glycol dehydration process, and optimize the operating parameters. Methods The sensitivity analysis method and response surface method were used to optimize the operating parameters. (1) Sensitivity analysis method was used to select the rich liquid entering- tower temperature, reboiler temperature. lean TEG circulation volume flow. stripping gas volume flow as factor variables, and to select dry gas water dew point and operating cost as response values. and 25 groups of test data were simulated by HYSYS software. (2) The response surface method was used to analyze and optimize these operating parameters. Results The interaction between rich liquid entering-tower temperature and stripping gas volume flow rate had the most significant influence on the dew point of dry gas water. and the interaction between rich liquid entering-tower temperature and lean TEG circulation flow rate had the most significant influence on the operating cost. The optimal process parameters were as follows: The temperature of rich liquid entering tower was 144. 28 C, the temperature of reboiler was 205.4 C. the circulation flow rate of lean TEG was 4 m³/h, and the volume flow of stripping gas was 24. 96 m/h. Under the condition that the dew point of dry gas water met the requirements of external transmission and the natural gas treatment capacity was 3 000 X 10³ m³/d. the operating cost could be reduced by 693 300 yuan per year. Conclusions The response surface method can be used to provide the theoretical basis of field operation parameter optimization. [ABSTRACT FROM AUTHOR]

Petrochemical equipment is characterized by continuity, large scale, complexity of processes, and critical operation conditions. Based on auto-collected monitoring parameters, online prediction of critical process parameters can be used to maintain high reliability of petrochemical equipment, which is generally unpractical due to interference parameters and the difficulty in establishing prediction models. In this paper, a process parameter online prediction method for petrochemical equipment is proposed. Firstly, sensitive parameters are selected applying gradient boosting decision tree (GBDT). Then optimized Gaussian process (GP) is utilized to develop a mapping model in order to inference process parameter from auto-collected parameters. Natural gas water dew point online prediction method for triethylene glycol (TEG) dehydration unit is investigated. The effectiveness of the proposed method is verified on production data of a natural gas dehydration station. The method proposed provides a promising solution for process parameter prediction for petrochemical processes as well as other similar scenarios. [ABSTRACT FROM AUTHOR]

Objective Aiming at the problem of freezing and blocking of pipeline transportation in remote wells and scattered wells in the Tahe area, a pilot construction project of a small dehydration station which is unattended was carried out. Methods Considering the special problems of the skid, the skid-mounted molecular sieve dehydration plan was worked out. The export natural gas water dew point during the trial operation was detected and the complicated working conditions of sudden power outage was simulated to analyze the potential risk factors and take corresponding preventive measures. Results After testing, the highest water dew point of exported natural gas was-28 ℃, and the whole skid runs reliably. It can also ensure security even in sudden power outages in the absence of intervention. Conclusions The 200×10³ m³/d unattended molecular sieve dehydration skid has great advantages in cost, dehydration effect and safety operation, especially suitable for relocation-possible devices or remote areas. At the same time, it also has great adaptability for complex and changeable special working conditions. The skid can be actively promoted and applied. [ABSTRACT FROM AUTHOR]

In this study, a water- and heavy hydrocarbon-removal process of a natural gas refinery currently in operation using the temperature swing adsorption method is modeled and investigated. The aim of this process is to decrease the hydrocarbon dew point to −10 °C and diminish the water content of the gas to about 0.1 ppm. This unit consists of four beds with two layers in which two beds are in the adsorption state, while the others are kept in the regeneration state. The gas composition and the bed specification are obtained from the available data from the refinery. The Ergun equation is considered for the pressure drop calculation. The results show that the developed model can predict the outputs with good accuracy. Sensitivity analysis of operating condition parameters such as temperature, pressure, and regeneration gas flowrate are carried out. Analysis of the regeneration temperature proved that temperature reduction from 268 °C to 210 °C can improve recovery of the heavy components. In addition, the regeneration gas flow rate can be reduced to about 0.4 kmole·s−1 as an optimum value. Moreover, 303 to 310 °C is the optimum range for the feed temperature. Due to the presence of the air cooler in the upstream process, and according to the ambient air temperature, feed temperature can be decreased to obtain better results. [ABSTRACT FROM AUTHOR]

Objective In the gathering and transportation of natural gas mines with high hydrogen sulfide content, in order to effectively reduce the corrosion hazard of hydrogen sulfide to the system, dehydration is often used to control the water dew point. Methods Based on the research of dehydration technology of high sulfur natural gas at home and abroad, triethylene glycol solvent absorption method was selected as the dehydration treatment process of high sulfur natural gas in Shunbei No. 2 area. Considering the characteristics of high sulfur natural gas in Shunbei No. 2 area, the traditional triethylene glycol dehydration process was optimized and improved locally, and the separation process before the raw gas inlet adsorption tower and the flash-vapor recovery process were added at the same time. Based on the influence of the pre-heating location, regeneration purity and hydrogen sulfide, the paper adopted a two-stage low-liquid/high-liquid heat exchange pre-heating process and LNG gasification gas extraction process to form a dehydration process which is suitable for high-sulfur natural gas in Shunbei No. 2 area. Results After transformation, the dehydration process realized zero discharge of sulfur-containing tail gas from dehydration system by pressurized recovery, and the combination of efficient desulfurization and purification of triethylene glycol (TEG) realized by LNG gasification and gas stripping, the problem of corrosion and maintenance of regeneration device in acid environment was solved. Conclusions This dehydration process effectively promoted the realization of the overall development plan of Shunbei No. 2 area, and formed a high-pressure gathering and transportation dehydration process suitable for natural gas with high hydrogen sulfide content in Shunbei No. 2 area, which provides technical support for the further development of Shunbei natural gas blocks. [ABSTRACT FROM AUTHOR]

Natural gas dehydration is a crucial step in gas processing, and three-flow vortex tubes have numerous advantages over traditional dehydration methods. In this study, a three-flow vortex tube with a sintered metal porous material as the drain part was developed. Further, the gas–liquid behavior within the main tube and sintered metal porous material (SMPM) was experimentally analyzed. Owing to the different driving forces, the gas and liquid first separate in the main tube, followed by further separation in the SMPM. With the SMPM as the drain part, the adverse impact of the drain processes and the amount of discharged gas from the drain port can be minimized compared to the traditional drain part with an annular space. The cooling performance dominated the dehydration ability of the three-flow vortex tube, and the largest dew point drop was 18.3 °C. Further, the largest total moisture content reduction ratio of the two exits was 61.1% at an inlet pressure of 2.0 bar and cold mass fraction of 0.45. Thus, it was demonstrated that the three-flow vortex tube with SMPM as the drain part is a potential device for gas dehydration. • A three-flow vortex tube with a SMPM as the drain part was developed. • The gas–liquid behavior within the main tube and SMPM was analyzed. • The largest φ t o t a l of the two exits was 61.1% at P in = 2.0 bar and ε = 0.45. [ABSTRACT FROM AUTHOR]