HTC Solvent Reclaimer System at Searles Valley Minerals Facility in Trona, California

Abstract

Chemical solvents such as alkanolamines that are used for CO2 capture from flue gases are vulnerable to quality deterioration which causes a number of operational challenges due to the accumulation of degradation products and other types of impurities within the solvent. To maintain solvent absorption efficiency and avoid operating problems, it is important to continuously remove the accumulated contaminants from the solvent by including a reclaiming process within large commercial CO2 capture plants. The new HTC solvent reclaimer system, called delta Reclaimer, has been integrated within the 800 ton per day CO2 amine capture plant at the Searles Valley Minerals Facility (SVM) to remove the undesirable contaminants from a solvent slipstream and return the clean solvent back to solvent circulation in the CO2 plant. The detailed analysis of the feed stream, product stream and waste stream shows that the delta Reclaimer is capable of removing most of the undesirable impurities and restoring the solvent to its original purity at a high recovery rate and minimum energy consumption. At normal operating conditions the recovery rate of the MEA solvent reaches 98% and the steam consumption is about 1 lb steam (40 psig) per 1 lb of recovered solvent. Very concentrated waste is collected periodically while the reclaimer process is in continuous operation. This technique contributed to a huge reduction of the quantity of waste collected for disposal.