Impact Assessment of Thermal Discharge from the Kemen Power Plant Based on Field Observation and Numerical Simulation

Abstract

Zeng, Z.; Luo, Y.; Chen, Z.J.; Tang, J.J.; Wang, Y.H., and Chen, C.H., 2020. Impact assessment of thermal discharge from the Kemen power plant based on field observation and numerical simulation. In: Guido Aldana, P.A. and Kantamaneni, K. (eds.), Advances in Water Resources, Coastal Management, and Marine Science Technology. Journal of Coastal Research, Special Issue No. 104, pp. 351–361. Coconut Creek (Florida), ISSN 0749-0208.The impact of the Kemen Power Plant thermal discharge on temperature rise in the ambient waters in the Luoyuan Bay was studied using field observation and numerical simulation. The scope of influence, indicated by the maximum temperature rise envelope curves during the observation period, was determined through field measurements of water temperature in the study area. The measurements revealed that the surface water with temperature rise diffused along the shoreline to the upstream and downstream of the power plant after the thermal discharge entered the sea. The longitudinal diffusion distance along the direction parallel to the shoreline was significantly longer than the transverse diffusion distance along the direction perpendicular to the shoreline. The area with the maximum temperature rise was near the outfall. Under the field conditions given in this paper, the surface seawater temperature rise varied from a maximum of 10 °C near the outfall to 0.5 °C at a distance of 600 m from the shore. Temperature rise was mainly observed in the surface water, and the scope of influence rapidly diminished vertically with minimal temperature rise in the waters 3 m below the surface. Meanwhile, a 2-D tide field mathematical model and a thermal discharge diffusion model were developed to simulate the diffusion process of the power plant thermal discharge in the sea area. A comparison of the simulated results obtained under the same conditions as the field measurements showed that the established numerical model can effectively reflect the temperature diffusion of the thermal discharge, as well as the scope of full-tide maximum temperature rise at typical tide phases. Therefore, the numerical model of thermal discharge described in this paper can serve as a powerful tool to predict the impact of thermal discharge from power plants.