TECHNOLOGY SELECTION OF SULFUR RECOVERY FOR LOW H2S ACID GAS AND HEAT UTILIZATION FOR A MOTIVE FLUID OF STEAM TURBINE

• Main Author: Sunaryono
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/33523
• Institution: Institut Teknologi Bandung

In natural gas processing industry, the removal process of acid gases such as H2S and CO2 is needed in order to meet sales gas specification. Several gas fields in Indonesia have concentration of H2S 1,000-6,000 ppm and CO2 2-5%-mole. Acid gas from the Acid Gas Removal Unit will be treated to the Acid Gas Conversion Unit to convert as stable product and tail gas comply with the emission limit regulation. A preliminary analysis based on qualitative criteria has been performed to 4 (four) technologies including process Claus Selectox, Wet Oxidation (Redox), Thiopaq and Wet Sulfuric Acid (WSA). The Claus Selectox and WSA technology has been selected will be evaluated further the process performance and the economic analysis. From simulation result with capacity of 6-20 MMscfd and H2S 2-12%-mole shows that all two technology can convert acid gas meet the elemental sulfur/sulfuric acid product specification and tail gas comply with the emission limit regulation. The Claus Selectox technology can produce elemental sulfur of 91 Ton/day (99,9%-wt) and heat utilization of 8.2 MMBtu/hr (electricity 0.6 MW) require capital cost of MUS$ 31.2. On the other hand, the WSA technology can produce sulfuric acid of 284 Ton/day (98.2%-wt) and heat utilization of 139 MMBtu/hr (electricity 9.7 MW) require capital cost MUS$ 22.6. The WSA technology (IRR=16.25%, NPV=MUS$41.1 and POT=6.5 years) gives more economical benefit compared to the Claus Selectox technology (IRR=6.62%, NPV=MUS$9.32 and POT=11.9 years). From the process performance and the economic analyses that have been done for this study, the WSA technology is recommended as a preferred technology to recover low H2S in acid gas and heat utilization for generating the electricity power. Keywords: Natural Gas, Acid Gas Removal Unit, Acid Gas Conversion Unit, Claus Selectox technology, Wet Sulfuric Acid technology