Kaihua Guo

Natural gas storage in hydrates with the presence of promoters

Abstract Hydrate technology is being developed for the storage and transport of natural gas. Micellar surfectant solutions were found to increase the gas hydrate formation rate and storage capacity. An anionic surfactant, a nonionic surfactant, their mixtures and cyclopentane were used to improve the hydrate formation of a synthetic natural gas (methane=92.05 mol%, ethane=4.96 mol%, propane=2.99 mol%) in a quiescent system in this work. The effect of an anionic surfactant (sodium dodecyl sulfate) on natural gas storage in hydrates is more pronounced compared to the effect of a nonionic surfactant (dodecyl polysaccharide glycoside). Cyclopentane could reduce hydrate formation induction time but could not improve the hydrate formation rate and storage capacity.

High temperature hot water heat pump with non-azeotropic refrigerant mixture HCFC-22/HCFC-141b

A water-to-water high temperature heat pump was studied experimentally. The performance of the system was characterized by refrigerant compositions, compressor RPM and water temperature change. For the experimental conditions of the inlet water temperature of evaporator of 40 °C and the inlet and outlet water temperatures of the condenser of 70 and 80 °C, respectively, the experiment shows that the coefficient of performance is maximum when the molar component of R22 is about 75%. It is shown that the maximum pressure of the system is under 2.5 MPa after taking R22/R141b as working fluids, even though the highest cooling water temperatures is about 80 °C.