The thermodynamic analysis and adjusting methods for reliquefaction plant on board LEG carriers

Publisher Summary This chapter covers the thermodynamic analysis and adjusting methods for reliquefaction plant on board LEG carriers. The real capacity of the reliquefaction plant on board the ethylene carrier depends on the knowledge and skills of the ship cargo engineer to a great extent. Aimed at optimum operation, thermodynamic analyses are made on refrigerating cycles of the plant. The maximum cooling rate mode and the optimum energy-conservation mode are brought forward. Ethylene tank temperature is forecasted; optimum-operating mode is chosen, and the division point is determined. The key thermodynamic parameters of liquid and vapor include saturation pressure and temperature, specific volume, enthalpy, entropy, exergy, available energy, etc. The plant working condition varies all the time. According to Mollier diagram and regarding refrigeration coefficient (ɛ) as goal function, the thermodynamic calculation has been carried out (computational process omitted). Meanwhile, various influencing factors and working parameters of the plant are discussed.