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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]

Dehydration is a critical operation in natural gas conditioning as it reduces the potential for corrosion, hydrate formation and freezing in process equipment and transportation pipelines. Water dew point adjustment is particularly challenging in the remote ultra-deepwater natural gas reserves of the Brazilian Pre-Salt fields due to their very high carbon dioxide contents – from 30% up to 90% in raw natural gas – which is a consequence from the carbonaceous rock of the reservoir structure and long term elevation of carbon dioxide content due to its injection for early enhanced oil recovery. Under this scenario, the study evaluates the impact of the carbon dioxide content of the natural gas on the performance of water dew point via water adsorption on 4 Å Zeolite molecular sieve beds. Process simulation with adsorption simulator Adsim (Aspen Technology, Inc), at varying operation pressures and carbon dioxide contents in raw natural gas, indicated that, although adsorption meets water removal specification in a condensation free operation, the high fugacity of carbon dioxide penalizes the dehydration performance due to probably two facts: (i) higher carbon dioxide fugacity in the humid natural gas imply higher saturation water content in the gas phase, which increases the service of dehydration units; and (ii) higher carbon dioxide fugacity in the humid natural gas establishes a discreet adsorption competition with water resulting in 6.5% increase of adsorbent bed volume for operating pressures of 35 bar or higher. [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]

Triethylene glycol (TEG) is one of the most effective sorbents for natural gas dehydration. There are many processes using this approach but none of them can combine high performance and economical energy consumption. In this study hydrocarbon-water phase behavior was investigated for different TEG concentrations in different natural gas dehydration processes. The equilibrium correlations were investigated for predicting water dew point as a function of TEG concentration. The effect of TEG concentration on the outlet gas dew point was also determined using phase envelope diagrams. The results showed that the (DRIZO) process achieved the most significantly reduces water dew point followed by conventional stripping gas dehydration process. Moreover, TEG was modified using potassium formate as additive. The results showed that the absorption capacity of the modified TEG was improved, that is almost duplicated. This modification augments the performance of the proposed mixture which can be potentially applied to a real scale process. [ABSTRACT FROM AUTHOR]