CO2 desorption from activated DEA using membrane contactor with vacuum regeneration technology

Nidia Intan Listiyana,Siti Nurkhamidah,Yusuf Zaelana,Yeni Rahmawati,Hafan Rofiq Syahnur,A.C Kumoro,A.W Lothongkum,S.A Roces,P.T.S Nam,X Rong,M.T Phong,L Yung,M.A Hussain,W.R.W Daud,Hadiyanto Hadiyanto

doi:10.1051/matecconf/201815608012

Abstract

Carbondioxide (CO2) content in natural gas must be removed because it inhibits liquefication process of natural gas. CO2 gas separation technology using membrane contactor has been developed, however solvent regeneration using membrane contactors are still rare because it requires a larger energy. The regeneration process by using membrane vacuum technology was put forward to reduce the regeneration energy consumption. In this work, arginine, piperazine (PZ), and potassium carbonate (K2CO3) as activators were added into diethanolamine (DEA) solution to form aqueous solutions of activated DEA. The experiment of CO2 desorption from activated DEA was carried out in hollow fibre membrane contactor (HFMC). The solvent with rich CO2 at 30-70°C was flowed in the lumen of the hydrophobic polypropylene HFMC, and the shell side was maintained at a reduced pressure by a vacuum pump at 20 kPa. The effect of solvent temperature and activators were investigated to get CO2 desorption flux and regeneration efficiency. Experimental result shows that increasing of solvent temperature could enhance CO2 desorption flux and regeneration efficiency. Instead of that, the activated DEA also give better result compared with non-activated DEA. Among three activators, K2CO3 give the best result for desorption flux and regeneration efficiency.

Highlights

Natural gas is the third largest natural resource in the world after coal and petroleum
In the process of Liquefied Natural Gas (LNG) processing, CO2 content must be removed to prevent icing during natural gas liquefaction process, because the process runs at very low temperatures of -161 ° C while the freezing point of CO2 around -78.4°C [14]
The reversible reaction equilibrium constant and CO2 diffusivity in DEA solution increased with the solution temperature, which leads to the improvement of desorption performance as well

Summary

Introduction

Natural gas is the third largest natural resource in the world after coal and petroleum. Natural gas processing industry is an important sector in supplying energy or fuel. Combustion of natural gas only produce half of CO2 and 33% compared to oil. The high potential of natural gas resources increasing efforts to develop more effective and efficient processing in terms of operations, economics, and environment. In natural gas processing processes where the main component is a hydrocarbon must be separated from impurity components such as CO2, H2S, N2, and water vapor as they may affect the quality and processing of natural gas further. CO2 as an impurity in natural gas can cause corrosion of piping and equipment, otherwise CO2 is able to decrease the heating value of natural gas [15]. In the process of Liquefied Natural Gas (LNG) processing, CO2 content must be removed to prevent icing during natural gas liquefaction process, because the process runs at very low temperatures of -161 ° C while the freezing point of CO2 around -78.4°C [14]

Methods

Discussion

Conclusion