Simulation and Optimization of Demercaptanization of Propane and Butane in South Pars Gas Refineries

Bijani, Abdolmotaleb; Esmaeili-Faraj, Seyyed Hamid; Daei Moghaddam, Mojtaba

Simulation and Optimization of Demercaptanization of Propane and Butane in South Pars Gas Refineries

Document Type : Original Research

Authors

A. Bijani ¹

S. H. Esmaeili-Faraj ²

M. Daei Moghaddam ³

¹ ACECR Institute of Higher Education (Isfahan Branch

² Assistant Professor, Chemical and Material Engineering, Shahrood University of Technology

³ Chemical Engineering Department, Quchan University of Technology, Quchan, Iran.

Abstract

Propane and butane that are the contents of LPG are separated from natural gas in the unit 107 of 5^th refinery of South Pars Gas Company (SPGC). The concentration of methyl mercaptan and ethyl mercaptan in the propane stream are 551 and 46ppm, respectively, and the concentration of these components in butane stream are 1218 ppm and 0.8%, respectively. In order to remove mercaptans from butane and propane, aqueous solution of sodium hydroxide with 15 to 20% wt. is used for the scrubbing. In this research, using the Petro-SIM software, which is a particular simulator for oil and gas industries, the units 113, 114, and 115 of 5^th refinery of SPGC are simulated. The results of the simulation are compared with the data of both experimental data and design documents, and they are goodly match. Then, using the software optimizer the operating parameters is optimized. The optimization results show that by increasing the extraction temperature in the unit of 115 up to 46 ° C, the concentration of mercaptan in the products can be reduced. The other independent parameters do not affect the final result of the process.

Keywords

simulation

Optimization

Demercaptanization

Petro-SIM software

LPG

Subjects

Petroleum Engineering

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