Development of a 250-kWe Class Supercritical Carbon Dioxide Rankine Cycle Power Generation System and its Core Components

Abstract

Korea Institute of Machinery & Materials (KIMM) investigated a supercritical carbon dioxide (sCO2) cycle for a heat recovery power generation system for several years. The objective of the study focuses on the development of the technologies and the establishment of the development procedure of turbomachinery, heat exchangers, and auxiliary equipment for the sCO2 power cycle. A motor-driven centrifugal starter pump with an inducer is developed for startup operation. The main pump-drive turbine module adopts magnetic bearings as axial and radial bearings to remove oil lubrication and exhibits a hermetic structure to eliminate leakage problems. The power turbine and a generator are linked via a gearbox in the power turbine-generator module. An oil bearing and floating ring seal with dry gas injection are applied to minimize sCO2 leakage. The recuperator is developed as a printed circuit heat exchanger (PCHE) owing to its high efficiency and compactness. The integrated test facility is designed as a 250-kWe class sCO2 recuperated Rankine cycle to evaluate the performance of the core modules as opposed to demonstrating the viability of a particular sCO2 cycle. The test facility is proven to successfully operate in startup mode and self-sustaining mode using the starter pump and the main pump-drive turbine module. An overview of the operation of the startup mode and self-sustaining mode is presented.