Hydrate-based technology for CO2 capture from fossil fuel power plants

Abstract

Hydrate-based CO2 capture is a promising technology. To obtain fundamental data for a flowing system, we measured the distribution of pore solution to analyse hydrate formation/dissociation and gas separation properties. An orthogonal experiment was carried out to investigate the effects of glass beads, flow rates, pressures and temperatures on it. Magnetic resonance imaging (MRI) images were obtained using a spin echo multi-slice pulse sequence. Hydrate saturations were calculated quantitatively using an MRI mean intensity. The results show that hydrate blockages were frequently present. During the hydrate formation and dissociation process, the movement of the solution occurred in cycles. However, the solution movement rarely occurred for residual solution saturations obtained with a high backpressure. The solution concentrate phenomenon occurred mostly in BZ-04. The highest hydrate saturation was 30.2%, and the lowest was 0.70%. Unlike that in BZ-01, there was no stability present in BZ-02 and BZ-04. The different CO2 concentrations for the three processes of each cycle verified hydrate formation during the gas flow process. The highest CO2 concentration was 38.8%, and the lowest one was 11.4%. To obtain high hydrate saturation and good separation effects, the values of 5.00MPa, 1.0mlmin−1 and 280.00K were chosen. For the gas flow process, only the pressure had a significant impact on gas composition, and all the factors had a significant impact on the gas composition of the depressurisation process. The temperature had a significant impact on the gas composition of the hydrate dissociation process. The flow rate did not have a significant impact on the composition of the depressurisation process.