Decarbonization Challenges and Opportunities of Power Sector in Uzbekistan: A Simulation of Turakurgan Natural Gas-Fired Combined Cycle Power Plant with Exhaust Gas Recirculation

Abstract

Power generation dependency on natural gas in Uzbekistan is high, with more than 85% of the country’s electricity production coming from natural gas. Hence, natural gas-fired power plants constitute the largest proportion of the country’s greenhouse gas emissions. Carbon capture, storage, and utilization (CCSU) play an essential role in reaching Uzbekistan’s reduction targets for carbon dioxide (CO2) emissions. In this study, one (450 MW) of the two identical blocks of a 900 MW Turakurgan natural gas-fired combined cycle power plant (NGCCPP), located in the Fergana valley in Uzbekistan, is simulated using Aspen Plus® commercial software and is validated with its open access project data prior to the evaluation of end-of-pipe CCSU unit integration. An optimal value of exhaust gas recirculation (EGR) is identified in order to further increase the CO2 content in the flue gas while reducing the flue gas flow rate. In addition, according to the simulation results, more than 2.16 Mt of annual CO2 emissions can be avoided when the capture plant is set at a 90% CO2 capture rate. Apart from that, the suitability of various CCSU integration methods such as absorption, adsorption, membrane separation, and CO2 bio-fixation is discussed, considering the power plant’s site-specific conditions and the obtained flue gas stream characteristics.

Keywords

• CO₂ capture
• decarbonization
• combined cycle power plant
• Uzbekistan