Energy and exergy analyses of a novel integrated process configuration for tri-generation heat, power and liquefied natural gas based on biomass gasification

Abstract

Using renewable sources like biomass is a proper solution for solving the problem of deficiency of fossil energy simultaneously with the increasing trend of energy consumption in the world.In the present study, an integrated system of liquefied natural gas production was investigated through rice husk gasification and providing the needed power of the cycle by integrated gasification combined cycle, in a way that surplus heat generated in integrated gasification combined cycle was used in absorption refrigeration system to reduce liquefied natural gas cycle consumed power which resulted in the reduction of the cycle specific power from 0.2405 kWh/kg to 0.1794 kWh/kg. Pre-combustion carbon dioxide capture was used to absorb the generated carbon dioxide of the integrated system and its effect on system operation was studied and reported. Sensitivity analysis was performed by investigating the effect of generated nitrogen injection to the combustion chamber and also the effect of the generated steam rate on the suggested integrated system operation. Results show that combined heat and power efficiency gets to 48% in whole with the increase of steam production rate to 7 kg/s. The results obtained from the exergy analysis show that overall exergy efficiency and total irreversibility of the proposed system is 74.10% and 63,242 kW, respectively.