화학공학소재연구정보센터
International Journal of Energy Research, Vol.43, No.11, 5879-5896, 2019
Water usage and energy penalty of different hybrid cooling system configurations for a natural gas combined cycle power plant-Effect of carbon capture unit integration
Electric power generation from thermoelectric power plants is associated with a negative impact on water availability, referenced as the water-energy nexus, which is aggravated by climate change. In the present study, the effect of four different hybrid cooling system configurations on water usage and power penalty of a natural gas combined cycle has been investigated. The hybrid cooling system with a parallel connected indirect dry cooling system and wet cooling system is the most conventional studied hybrid cooling system in the literature, while the other studied hybrid configurations in the present study are novel regarding their effect on water requirement and power penalty. Simulations were conducted using the COCO 3.3 software and have been validated using data sets from a reference natural gas combined cycle plant, both with and without carbon capture unit, which is available in the literature. Four hybrid cooling system configurations were explored to evaluate their water requirements and power penalty. Other conventional cooling systems such as closed cooling, once-through, and direct and indirect dry cooling methods were simulated with and without postcombustion carbon capture (PCCC) integration for comparison. It was found that the hybrid configuration, including indirect air-cooled condenser and natural draft wet cooling tower, has the best performance as compared to the other conventional and hybrid cooling systems, amounting to 2.038 (gal/min)/MWnet, 1.573 (gal/min)/MWnet, and 12.29 MW for water withdrawal, consumption, and energy penalty, respectively, for the case of a unit without PCCC unit and 3.9 (gal/min)/MWnet, 2.928 (gal/min)/MWnet, and 15.177 MW for water withdrawal, consumption, and energy penalty, respectively, for a unit with carbon capture unit. It was confirmed that the PCCC integration approximately doubles the water withdrawal and consumption for all cooling systems. In addition, the indirect air-cooled condenser and wet cooling tower is still the best performing cooling system with PCCC integration.