An investigation of the cooling, heating and power systems integration with carbon capture and storage for LNG carriers

Abstract

This study investigates the cooling, heating and power (CHP) systems integration with the carbon capture and storage (CCS) for different LNG carriers. Different integration levels of conventional waste heat recovery, boil-off natural gas (BO-NG) reliquefaction, CO₂ capture and liquefaction, and ORC systems are modelled and simulated using Aspen HYSYS. Thermoeconomic optimisation is also carried out using Genetic algorithm method. Results demonstrate that using CCS system is more cost-effective than paying European Union carbon tax for LNG carriers. Integrating the BO-NG and CO₂ liquefaction cycles could reduce the total life cycle cost of the CCS system up to 17%. Optimised results show that selecting working pressure is very critical for the liquefaction of BO-NG and CO₂. CHP system using ORC reduces the energy penalty of the CCS system, however, it increases the total life cycle cost of the system due to its initial cost and relatively low exergy efficiency.