Creative absorber design and optimization for CO2 capture with aqueous piperazine. (January 2022)

• Record Type: Journal Article
• Authors: Gao, Tianyu; Rochelle, Gary T.
• Is Part Of: International journal of greenhouse gas control. Volume 113(2021)
• Publication Date: 2022-01
• Subjects: Carbon capture -- Piperazine -- Absorber design -- NGCC -- Pump-around; Greenhouse gases -- Environmental aspects -- Periodicals; Air -- Purification -- Technological innovations -- Periodicals; Gaz à effet de serre -- Périodiques; Gaz à effet de serre -- Réduction -- Périodiques; Air -- Purification -- Technological innovations; Greenhouse gases -- Environmental aspects; Periodicals; 363.73874605
• DOI: 10.1016/j.ijggc.2021.103534
• Languages: English
• ISSNs: 1750-5836

Abstract

Highlights: Creative absorber design using pump-around intercooling for a 460 MW NGCC power plant. Reduced absorber capital cost by using 7.6 m packing and eliminating DCC and trim cooler. Improved performance by using low pump-around temperature and high circulation rate. Flexible absorber operation strategy for various ambient temperatures. Abstract: The Texas Carbon Management Program is preparing a Front-End Engineering Design (FEED) of the PZAS TM (Piperazine with the Advanced Stripper TM ) for CO2 capture at a natural gas combined cycle power plant in West Texas. This paper develops the absorber design for the capture system and studies the operational strategies of the absorber in response to ambient temperature swing. The design uses 2 absorber trains, and each train integrates absorption and a water-wash section in one column. Each column has a cross-section area of 174 m 2 and consists of 3 sections of MellapakPlus® 252Y structured packing. Packing heights for each section are 3, 4.9, and 2.7 m from top to bottom. A pump-around intercooler applied at the bottom bed circulates solvent and eliminates the direct contact cooler. The baseline CO2 removal rate is 90% and will vary between 78% and 90% with ambient temperature. The system uses air cooling to eliminate cooling water usage. The water balance in the system will be managed by operating the water wash at a high circulation rate (1300 kg/h) to condense water during the night and make up for water loss during the day. The proposed design reduces the capital cost of the absorber column by minimizing the packing height and eliminating the direct contact cooler (DCC), and improves the energy cost by lowering the pump-around intercooling temperature and increasing the pump-around rate. Table of contents: Image, graphical abstract