Assisted Methane Hydrate Formation with the Addition of Promoters

Abstract

Natural gas hydrates play an important role in the largest reservoir of hydrocarbons on earth. The gas hydrates have received increasing attention in an excellent way of new technology for gas in large quantity storage and transportation. However, the main challenge to use methane hy¬drates has faced many challenges such as the slow formation rate, low growth rate during hydrate formation, and low conversion ratio of gas to solid hydrates leading to poor storage capacity. In this work, methane hydrate formation and dissociation in the presence of different Cyclopentane (CP), Tetra-n-butyl phosphonium bromide (TBPB) and Tetra-n-butyl ammonium bromide (TBAB) concentrations were investigated. The formation experiment was conducted in an unstirred system. The temperature was controlled between 2.5 and 4.0°C at 8 MPa. The hydrate dissociation experiment was performed after the completion of hydrate formation. The results showed that the presence of TBPB alone was not sufficient to promote methane hydrate formation. The addition of TBAB to promoted methane hydrate formation with only small amount of methane uptake. Increasing the concentration of CP improved methane consumption. However, the methane consumption in the presence of CP was higher than that with TBAB.