Raw natural gas must be processed to meet the sales specification of pipeline and gas distribution companies. Amine gas treating is one of the most common process for removal of acid gas. At the bottom of the absorption tower, rich amine solution leaves through an amine letdown valve before going to a flash tank, where a great portion of the physically absorbed gases separate from the amine solution. As a result, the rich amine letdown valve will see 2-phase flow through the system with entrained gas coming out of the solution, causing excessive vibration and severe erosion due to high velocity impingement of the liquid on the valve and trim. Proven valve solutions are available to address such problem if the phenomenon was overlooked at the design stage. If you are experiencing similar problem, the below case history may provide you the lead to addressing the problem.
http://www.documentation.emersonprocess.com/groups/public/documents/case_history/d351746x012.pdf