Steam Regeneration of Exhausted Activated Carbon Used in Natural Gas Dehydration by a Triethylene Glycol Unit

This study investigated the optimization of regeneration of exhausted activated carbon (EAC) by hydrocarbons used in natural gas dehydration plants. Various methods were used including chemical, thermal, and steam regeneration. The experimental results demonstrated the effectiveness of steam regeneration of EAC at low temperatures, which was further enhanced by pre-regenerating EAC with dilute acid (2.5% hydrochloric acid). In addition, an evaluation of the regenerated activated carbon (RAC)’s performance against hydrocarbons from exhausted triethylene glycol (ETEG) was conducted using three parameters: the iodine number in EAC, the refractive index, and the density of triethylene glycol (TEG) regenerated for testing the adsorption capacity. The results showed that the adsorption capacity of RAC to hydrocarbons from ETEG increased with rising temperature, resulting in highly pure, hydrocarbon-free TEG suitable for use in natural gas TEG dehydration plants. The optimized steam regeneration method with dilute acid pre-treatment demonstrated significant potential for improving the efficiency and sustainability of natural gas dehydration processes. These findings have important implications for the design and operation of steam regeneration units in industrial settings. Moreover, this study contributes to the growing body of research on sustainable and cost-effective methods for hydrocarbon removal in the gas processing industry.