Demonstration of a Concentrated Potassium Carbonate Process for CO₂ Capture

Abstract

A precipitating potassium carbonate (K2CO3)-based solvent absorption process has been developed by the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) for capturing carbon dioxide (CO2) from industrial sources, such as power plant flue gases. Demonstration of this process is underway using both a laboratory-based pilot plant located at The University of Melbourne and an industrial pilot plant located at the Hazelwood Power Station in Victoria, Australia. The laboratory-scale pilot plant has been designed to capture 4–10 kg/h CO2 from an air/CO2 feed gas rate of 30–55 kg/h. The power-station-based pilot plant has been designed to capture up to 1 tonne/day CO2 from the flue gas of a brown-coal-fired power station. In this paper, results from trials using concentrated potassium carbonate (20–40 wt %) solvent are presented for both pilot plants. Performance data (including pressure drop, holdup, solvent loadings, temperature profile, and CO2 removal efficiency) have been collected from each plant and presented for a range of operating conditions. Plant data for the laboratory-scale pilot plant (including temperature profiles, solvent loadings, and exit gas CO2 concentrations) have been used to validate and further develop Aspen Plus simulations, in anticipation of further work involving precipitation and the industry-based pilot plant.

CO2 capture with potassium carbonate solutions: A state-of-the-art review

“…Addition of 3 wt% boric acid to 30 wt% K 2 CO 3 did not show significant effect on the CO 2 absorption amount because boric acid caused the pH reduction and, consequently, the amount of OH − reduced the rate of the controlling kinetic reaction to form KHCO 3 from CO 2 . In another study, Smith et al (2013) used 20-40 wt% K 2 CO 3 without promoter in a laboratory-scale pilot plant. Capannelli et al (2013) compared the performance of MEA, PZ, and PC solutions on the CO 2 absorption rate in a polymeric membrane system.…”

“…As a result less water is needed for the stripper. This reduces the energy requirement Smith et al, 2013). The UNO MK 3 process is expected to yield significant cost reductions as compared to the amine-based processes.…”

Producing pipeline-quality biomethane via anaerobic digestion of sludge amended with corn stover biochar with in-situ CO2 removal

“…Surface-rich basic sites in the biochar, in particular, high K concentration (14.2 ash% K 2 O) promote in-situ CO 2 removal in the digester. Potassium carbonate (K 2 CO 3 ) has been widely used for CO 2 absorption in industry as a viable commercial process [35]. Additionally, various amino acids produced from sludge hydrolysis in the digester may promote potassium-mediated CO 2 absorption [36].…”

Review of solvent based carbon-dioxide capture technologies

“…CO2CRC and the University of Melbourne have been investigating K 2 CO 3 systems over a long period and the most recent development is a precipitating system termed UNO MK3 with several pilot facilities [114]. Trials at GDF SUEZ's Australia Energy plant at the Hazelwood Power Station in the Latrobe Valley, Victoria have recently been completed [115].…”