THERMODYNAMIC ANALYSIS OF ELECTRIC POWER PRODUCTION TECHNOLOGIES IN COGENERATION SYSTEMS ON FPSO AIMING TO REDUCE CO2 EMISSIONS

Abstract

Oil platforms are complex structures used to host workers and equipmentneeded in offshore exploration. This study focuses on the platform's heatand electricity cogeneration plant, which supplies a process heat exchangersnet, and provides the necessary electricity for all the equipment used for theprocess and worker's accommodation in the platform. The platform demandwith maximum load is 75 MW, which could be achieved using four gasturbines (25 MW each), one of which is kept for backup purposes or usingsix dual-fuel engines diesel/natural gas (15 MW each), one of which is alsokept for backup purposes. Therefore, the thermodynamic analysis wasperformed - considering five specific demand points of the platform -comparing the two traditional configurations (gas turbines and dual-fuelengines diesel/natural gas) and a combined configuration. The combinedconfiguration is composed of three gas turbines and two dual-fuel enginesdiesel/natural gas (one of the gas turbines kept for backup purposes). Theconfigurations presented respectively 35.5%, 48.4% and 42.6% at highestoverall efficiency; 611.34 g/kWh, 373.45 g/kWh, 472.74 g/kWh at lowestCO2 emissions considering full attendance of electrical and thermaldemands. The configurations using only gas turbines and the combinedfully attended the thermal demand of the platform without using auxiliarypieces of equipment. Therefore, it was possible to observe that thecombined configuration presented several advantages concerning isolatedsystems, proving to be an excellent option for sustainable energygeneration, reducing emissions of polluting gases and greater flexibility ofits operation concerning to configuration only with turbines, and physicaloccupation in relation to configuration only with engines.