DOI QR코드

DOI QR Code

Optimization Strategies for Amine Regeneration Process with Heat-Stable Salt Removal Unit

열 안정성 염 제거장치를 고려한 아민 재생 공정 최적화 전략

  • Lee, Jesung (Green Materials and Processes R&D Group, Korea Institute of Industrial Technology) ;
  • Lim, Jonghun (Green Materials and Processes R&D Group, Korea Institute of Industrial Technology) ;
  • Cho, Hyungtae (Green Materials and Processes R&D Group, Korea Institute of Industrial Technology) ;
  • Kim, Junghwan (Green Materials and Processes R&D Group, Korea Institute of Industrial Technology)
  • 이제성 (한국생산기술연구원 친환경재료공정연구그룹) ;
  • 임종훈 (한국생산기술연구원 친환경재료공정연구그룹) ;
  • 조형태 (한국생산기술연구원 친환경재료공정연구그룹) ;
  • 김정환 (한국생산기술연구원 친환경재료공정연구그룹)
  • Received : 2020.09.07
  • Accepted : 2020.09.23
  • Published : 2020.10.12

Abstract

In this study, we simulated an amine regeneration process with heat-stable salts removal unit. We derived the optimal operating conditions considering the flow rate of waste, the removal rate of heat-stable salts, and the loss rate of MDEA (methyl diethanolamine). In the amine regeneration process that absorbs and removes acid gas, heat-stable salt impairs the absorption efficiency of process equipment and amine solution. An ion exchange resin method is to remove heat-stable salts through neutralization by using a strong base solution such as NaOH. The acid gas removal process was established using the Radfrac model, and the equilibrium constant of the reaction was calculated using Gibbs free energy. The removed amine solution is separated and flows to the heat-stable salts remover which is modeled by using the Rstoic model with neutralization reaction. Actual operation data and simulation results were compared and verified, and also a case study was conducted by adjusting the inflow mass of removal unit followed by suggesting optimal conditions.

본 연구에서는 열 안정성 염 제거장치가 추가된 아민 재생 공정을 모사하고, 폐수 량, 열 안정성 염 제거 량, MDEA(methyl diethanolamine) 손실량을 고려한 최적 운전조건 도출 전략을 제시하였다. 산성 가스를 흡수 및 탈거하는 아민 재생공정에서 열 안정성 염은 공정 장비 및 아민 용액의 흡수 효율을 저해한다. 열 안정성 염 제거 방법 중 하나인 이온교환수지법은 NaOH와 같은 강 염기성 용액을 사용하여 중화반응을 통해 염을 제거시키는 방법이다. 공정 모델링 과정에서 산성 가스의 탈거 과정은 Radfrac 모델을 사용했고, 반응의 평형상수는 Gibbs 자유에너지를 사용하여 계산하였다. 탈거된 아민 용액의 일부는 열 안정성 염 제거 장치로 들어가게 되고, 제거 장치는 중화반응을 이용한 Rstoic 모델을 사용하였다. 실제 운전데이터와 시뮬레이션 결과를 비교하여 검증하였고, 제거 장치로 들어가는 질량 유량을 조절하여 사례연구를 하고 최적 운전 조건을 제시하였다.

Keywords

References

  1. H. Ghanbarabadi and B. Khoshandam, Simulation and comparison of Sulfinol solvent performance with amine solvents in removing sulfur compounds and acid gases from natural sour gas, J. Nat. Gas Sci. Eng., 22, 415-420 (2015). https://doi.org/10.1016/j.jngse.2014.12.024
  2. N. Verma and A. Verma, Amine system problems arising from heat stable salts and solutions to improve system performance, Fuel Process. Technol., 90, 483-489 (2009). https://doi.org/10.1016/j.fuproc.2009.02.002
  3. B. Strazisar, R. Anderson, and C. White, Degradation pathways for monoethanolamine in a $CO_2$ capture facility, Energy Fuels, 17, 1034-1039 (2003). https://doi.org/10.1021/ef020272i
  4. Y. Tavan, M. Moradi, and A. Rostami et al., Theoretical and industrial aspects of amine reclaiming unit to separate heat stable salts, Sep. Purif. Technol., 237, 116314 (2020). https://doi.org/10.1016/j.seppur.2019.116314
  5. H. J Liu, J. W. Dean, and S. F. Bosen, Neutralization technology to reduce corrosion from heat stable amine salts, NACE International, Orlando, Florida (1995).
  6. L. Cummings, G. D. Smith, and D. K. Nelsen, Advances in amine reclaiming - Why there's no excuse to operate a dirty amine system, Laurance Reid Gas Conditioning Conference, February, Oklahoma (2007).
  7. F. Pani, A. Gaunand, D. Richon, R. Cadours, and C. Bouallou, Absorption of $H_2S$ by an aqueous methyldiethanolamine solution at 296 and 343 K, J. Chem. Eng. Data, 42, 865-870 (1997). https://doi.org/10.1021/je970062d
  8. J. C. Polasek, J. A. Bullin, and S. T. Donnelly, Alternative flow schemes to reduce capital and operating costs of amine sweetening units, Bryan Research and Engineering. Inc, Bryan, Texas (2006).
  9. C. Chen and Y. Song, Generalized electrolyte-NRTL model for mixed-solvent electrolyte systems, AlChE Journal, 50, 1928-1941 (2004). https://doi.org/10.1002/aic.10151
  10. X. Tian, L. Wang, D. Fu, and C. Li, Absorption and removal efficiency of low-partial-pressure $H_2S$ in a monoethanolamine-activated N-methyldiethanolamine aqueous solution, Energy Fuels, 33, 629-635 (2019). https://doi.org/10.1021/acs.energyfuels.8b03550
  11. J. Lim and J. Kim, Optimization of a wet flue gas desulfurization system considering low-grade limestone and waste oyster shell, J. Korea Soc. Waste Manag., 37, 1-12 (2020). https://doi.org/10.9786/kswm.2020.37.1.1
  12. H. Meng, S. Zhang, C. Li, and L. Li, Removal of heat stable salts from aqueous solutions of N-methyldiethanolamine using a specially designed three-compartment configuration electrodialyzer, J. Membr. Sci., 322, 436-440 (2008). https://doi.org/10.1016/j.memsci.2008.05.072