Preliminary Plant Design of Sweet Gas From Natural Gas at a Capacity of 250.000 Ton/Year.

Oleh :
Ezz Aldeen Abdelmawla - I0522125 - Fak. Teknik

AbstractThe increasing demand for energy in Libya, particularly for electricity generation, has intensified the need for a reliable supply of high-quality natural gas. However, raw natural gas produced from Libyan reservoirs contains significant concentrations of acid gases, primarily hydrogen sulfide (H₂S) and carbon dioxide (CO₂), which reduce its heating value, promote equipment corrosion, and pose environmental and operational challenges. This study presents the preliminary design of a natural gas sweetening plant with a production capacity of 250,000 tons per year, aimed at improving natural gas quality to meet commercial pipeline specifications and support Libya’s growing domestic energy demand.The proposed plant utilizes the chemical absorption process with methyldiethanolamine (MDEA) as the sweetening solvent due to its high selectivity for H₂S removal, lower regeneration energy requirements, superior chemical stability, and reduced corrosion compared with conventional amine solvents. Process selection was carried out through a comparative evaluation of available gas sweetening technologies, including chemical absorption, physical absorption, adsorption, and membrane separation. MDEA-based absorption was selected based on its technical performance, economic feasibility, and widespread industrial application.The design capacity was determined by analyzing projected domestic natural gas demand, production trends, export levels, and the capacities of existing gas processing facilities. Demand forecasting indicates a continuous increase in natural gas consumption driven by electricity generation, while Libya's abundant gas reserves provide sufficient feedstock to sustain long-term plant operation. A capacity of 250,000 tons per year was selected as the optimum scale to complement existing processing infrastructure while maintaining operational flexibility and economic viability. The proposed plant is strategically located near the Messla Field to minimize feed gas transportation costs, utilize existing pipeline infrastructure, and facilitate downstream distribution through Marsa El Brega and the Greenstream Pipeline.The proposed facility is expected to produce pipeline-quality sweet natural gas with H₂S concentrations below 5 ppm and CO₂ concentrations below 4 mol%, making it suitable for domestic power generation and export markets. In addition to enhancing energy security and supporting sustainable industrial development, the project contributes to environmental protection by reducing acid gas emissions and improving the overall efficiency and value of Libya's natural gas resources.Keywords: Natural gas sweetening, MDEA, Claus Process , Sulfur Recovery Unit (SRU) ,Tail Gas Treatment Unit (TGTU).