Recovery of Argon from Ammonia Purge Stream

Abstract

In the past 30 years, the chemical industry has been the subject of notable changes due to higher demands and increasing production and operational costs. As a result, it has become imperative for chemical industries to focus on the utilization of products having great economical potential. Chemical processes must be made efficient physically and within the reasonable constraints. Chemical engineers are obliged to find betteroperating strategies and products that are valuable yet easy to extract from an existing chemical process. The separation of Argon from the Purge Gas of FFC-1 can generate a revenue of 15 million US dollars per annum which is a significant step towards stability and economic benefit. It will provide positive contribution towards the plants’ profitability and in turn, prosperity of the country. Therefore, this study is focused on the statistical determination of optimum operating parameters for the separation of Argon from the purge gas stream at FFC-1. The separation of Argon from Ammonia purge gas will utilize available resources and convert it into revenue generator. In this project, two methods namely a cryogenic method and a membrane separation method have been proposed to recover Argon from the Hydrogen depleted purge gas that is, otherwise, being flared in the industry. The process begins with an adsorption column followed by a Palladium (Pd) membrane system to remove Methane and the remainder of Hydrogen, respectively. The cryogenic process consists of a cryogenic distillation column that separates Argon while the latter one features a cascaded polymeric membrane system to recover the same. Both the processes are presented with elaborate detail along with process flow diagrams, material and energy balances, equipment design, simulation, costing and HAZOP analysis. A comparison is given in the end as to determine which method works best.