Experimental investigation on thermal energy transportation by CO2 hydrate

Optimum conditions for an efficient long-distance thermal energy transportation system using CO2 hydrate slurry are evaluated in a lab-scale environment. The properties of CO2 hydrate grant its purpose as a secondary refrigerant considering the high dissociation enthalpy. High pressure and low temperature conditions are required for stable hydrate formation and therefore, tetrahydrofuran (THF) is selected to ease the formation conditions for pure CO2 hydrate. The experiments are conducted based on various THF concentrations, formation pressure, and temperature conditions. Two heat exchangers are installed for the formation and dissociation of CO2+THF hydrate slurry. Heat transfer rates for both heat exchangers and coefficient of performance are evaluated. Pressure drop is obtained during the transportation process from the formation heat exchanger to the dissociation heat exchanger. Consequently, a hydrate based optimized system is assessed for long-distance heat transportation applications.