Exploring Thermal Barrier and Sedimentation Simulation for Enhanced Performance in Grati Combined Cycle Power Plant

Abstract

PLTGU is a power generation facility that concurrently utilizes both steam and gas power plant technologies. It necessitates a cooling system to operate efficiently throughout its entire lifespan. If PLTGU Grati plans to increase its power capacity, there is a concern that the water discharged from the Water Outlet channel might not cool down sufficiently before re-entering the Water Intake channel. Additionally, sedimentation in the sea water uptake is causing siltation. Hence, this study focuses on the jetty extension project to address sedimentation and hot water spreading issues in PLTGU Grati. The numerical modeling analysis, conducted using the Delft3D software, indicates that in the case of power addition, Alternative Model 1 can reduce the highest temperature compared to the existing condition by 0.655°C. Similarly, Alternative Model 2 reduces the highest temperature by 0.090°C. Moreover, with power addition, sedimentation rate in Area 1 increases by 261.43 m3/month in Alternative Model 1, while in Alternative Model 2, it decreases by 969.47 m3/month compared to the existing condition. Considering the ability of Alternative Model 2 to effectively reduce the temperature in the inlet canals by 0.090°C, it provides the best solution to contain the spread of hot water in the PLTGU Grati area. Currently, PLTGU Grati employs a Cutter Suction Dredger (CSD) to periodically dredge the water inlet channel. Therefore, Alternative Model 2 is recommended as the optimal choice among the alternatives. Henceforth, detailed studies related to current patterns and sedimentation rates are presented comprehensively in this paper.