Enhanced Regeneration of Triethylene Glycol Solution by Rotating Packed Bed for Offshore Natural Gas Dehydration Process: Experimental and Modeling Study

Abstract

To address the problems of confined space for offshore application, rotating packed bed (RPB) was firstly used to enhance the regeneration of TEG solution in natural gas dehydration process. The performance of the regeneration, which was exhibited in terms of the desorption efficiency and mass transfer coefficient, was investigated experimentally. The effects of various operating parameters, including rotation speed, gas-liquid ratio, liquid flow rate, liquid inlet temperature, and inlet concentration of rich TEG were studied to assess the impacts on the regeneration process. It was found that the purity of regenerated TEG solution by RPB was basically above 99.7% under a common gas-liquid ratio of 45 (volume ratio), and even higher than 99.98% under the optimal conditions. A mass transfer model combined two-film theory and penetration theory was established, which could well predict the TEG solution regeneration performance in RPB. According to the established model and ASPEN simulation result, an RPB and a packed column were designed respectively for a specific TEG regeneration task. It was found the volume reduction factor of RPB was about 8, which showed well adaptation of RPB for the offshore natural gas extraction due to the outstanding mass transfer performance in the TEG regeneration process.