[Objective] To address the issues of heat stable salts(HSS) accumulation

absorption performance degradation

and amine loss caused by amine solvent degradation in the 150 000 tons/year coal-fired flue gas carbon capture demonstration project by chemical absorption at Guoneng Jinjie Energy Co.

Ltd.

a 10 m³/h amine-based absorbent purification and recovery unit was developed to study its operational performance. A secondary recovery process was introduced to enhance the amine recovery efficiency. In this study

72-hour continuous operation of an industrial unit utilizing electrodialysis for amine absorbent purification and recovery was achieved

and the contents of HSS mass fraction

HSS removal efficiency

amine mass fraction

amine reclaiming efficiency

and mass concentration of suspended solids were tested to verify the operational performance of the unit. [Methods] Conductivity measurement was employed to rapidly assess the desalination endpoint during actual operation. Acidbase titration was utilized to determine the total HSS content in both standard solutions and the actual amine solution

while ion chromatography was employed to analyze the removal efficiency of specific HSS components. [Results] The HSS mass fraction was reduced from over 2% to below 0.9%

achieving a maximum removal efficiency of 91.72% after primary purification. Notably

the removal efficiencies for formate and oxalate reached 95.29% and 96.48%

respectively. After the primary purification process

amine recovery efficiency was only 86.16%. However

after the secondary recovery process

amine recovery efficiency reached as high as 96.89%. After being replenished to the absorption system

the mass fraction of amine remained stable between 12.3% and 13.0%. The filtration part demonstrated high efficiency in removing suspended solids

achieving an average removal efficiency of 75.9%. After filtration

the mass concentration of suspended solids was significantly reduced to 24.5～25.8 mg/L. [Conclusion] The control system monitors the threshold of the electric conductivity of the outlet amine solution

and uses it as a key node for controlling the desalination process. By gradually adjusting the appropriate desalination degree

it reduces the HSS mass fraction in stages. The unit demonstrates highly efficient and stable desalination performance and amine recovery capability during long-term continuous operation. The secondary recovery process markedly improved the amine recovery efficiency. These results verify the feasibility of this technology for industrial CCUS systems

providing critical technical support for amine solvent regeneration and the long-term operation of carbon capture engineering projects.