Evaporation of liquefied natural gas in power stations - using cooling water to provide heat for evaporation

摘要

An arrangement for vaporising liquefied natural gas in a power station is equipped with gas-fired boilers, steam turbines and a condenser cooled by recirculated water. A storage tank is provided for the liquefied natural gas, which is evaporated in stages and delivered to the boilers during periods when the supply of gas from a normal supply pipe is inadequate. The improvement is that the fluid stage in the evapn. of the gas takes place in a heat exchanger in which the heat is provided by the condenser cooling water. The thermal efficiency of the tower station is increased by utilising heat normally wasted in a cooling tower. The cooling tower duty is correspondingly reduced and the effect of the cooling tower on the environment is reduced. Additional electrical power can be generated by a subsidiary turbine in which a refrigerant is expanded. The refrigerant is condensed in the first stage of the liquefied natural gas evapn. process.