Acid Gas Recovery
Carbon dioxide (CO2) is an inevitable by-product in syngas production, be it ammonia, hydrogen or hydrogen/carbon monoxide (HYCO) syngas. Valuable food grade CO2 can be recovered from these gases. Excess CO2 is usually vented as a waste product. CO2 is present in natural gas, ethylene and ethylene oxide plants. Low levels of CO2 are usually removed by caustic. Regenerable solvents such as amines and potassium carbonate are often used to remove large quantities of carbon dioxide.
With regenerable solvents, CO2 and/or H2S is removed from the raw gas stream in an absorber. The solvent loaded with the acid gas (now called rich solution) is usually sent to a reboiled regenerator. Vapors generated in a reboiler strip the CO2 out of the rich solutions. A typical process flow diagram is shown below.
In some cases, such as high pressure applications, a physical solvent can be used to minimize heat consumption. Physical solvents can be regenerated by simple flashing thus eliminating the use of a reboiler.
Koch Modular designs and supplies complete acid gas removal systems (AGR). Our engineers have more than 35 years of experience in the field, enabling us to optimize the process and equipment to provide AGR systems that are reliable and yet economically attractive.
For more information on how Koch Modular can help with your particular application, fill out an online project inquiry form.