Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8128034 | Journal of Natural Gas Science and Engineering | 2018 | 8 Pages |
Abstract
This work evaluates the efficiency of the aqueous mixture of Methyl Diethanolamine (MDEA) and Diethanolamine (DEA) at various mass concentrations to remove CO2 and H2S from natural gas in an industrial sweetening unit in Fajr Jam Gas Refining Company located in the south of Iran and gives recommendations for modifying the process. The sweetening unit includes absorber and desorption towers, flash drum, lean and rich amine exchanger, kettle type reboiler and a reflux drum. The considered process is simulated by Promax simulator (version 3.2) taking into account operational constraints and sustainability of the environment. The validity of simulation has been evaluated by comparison between simulation results and the plant data. The main objective of this work is the modification of natural gas sweetening unit to achieve lower energy consumption. Thus, the effect of amine circulating rate and MDEA to DEA ratio on steam consumption in the regeneration tower, CO2 and H2S concentration in the treated gas, and the acid gas loadings have been investigated. Therefore, substitution of DEA solvent in the unit with the aqueous mixture of DEA and MDEA is proposed. In the examined cases, the mass concentration of MDEA and DEA lies between 15 and 45â¯wt% and 0-30â¯wt%, respectively, with the reference cases having MDEA 0â¯wt% and DEA 31.6â¯wt%. The results show that in the proposed cases of alternative mixtures including cases 1 (MDEA15â¯wt% and DEA 30â¯wt%), 2 (MDEA 20â¯wt% and DEA 25â¯wt%), and 3 (MDEA 25â¯wt% and DEA 20â¯wt%) the amount of reduction in amine circulation rate are between 11.1%v/v and 19.4%v/v compared to the original amine circulation rate. Likewise, steam consumption decreases between 24.4 %wt/wt and 27 %wt/wt. Influence of anti-foam injection for the different cases were also studied and it was found that anti-foam with the concentration of 5000 ppmv is more suitable for the optimum operation and is a more cost effective.
Keywords
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Earth and Planetary Sciences (General)
Authors
Mahdi Kheirinik, Nejat Rahmanian, Mohammad Farsi, Mehdi Garmsiri,