DIMETHYL ETHER PLANT DESIGN FROM CO2 KRAKATAU STEEL WITH CAPACITY OF 33,000 TON/YEAR

Abstract

The carbon dioxide emission has been increasing as the use of massive fossil fuel. Therefore, the research has been conducted to converted CO2 into valuable chemicals. The promising chemical from CO2 is dimethyl ether (DME) as it has potential to reduce the carbon dioxide and to minimize the use of imported Liquified Petroleum Gas (LPG). This plant is planned to be established in Cilegon, Banten, in 2026 with a land area of 168,822 m2. The DME production capacity in this plant is 33,000 ton/years which operates for 330 days in a year. Another raw material for synthesis of DME is hydrogen. The hydrogen is obtained from water splitting in electrolyser. The first synthesis is the CO2 hydrogenation to methanol in fixed bed multitube reactor with the help of a catalyst of Cu/ZnO/Al2O3. The unreacted reactant will be further reacted in the second reactor to increase the conversion. The unreacted reactant from second reactor will be recycle to the first reactor. The product from both reactors will be continued to the distillation purification process so that the methanol purity will higher. The methanol then will be reacted to DME and water in the fixed bed multitube reactor with the help of Al2O3 catalyst. The DME then will be further purify in the purification unit using distillation column. This plant does not produce toxic industrial waste thus made this plant environmentally friendly. The utility needed for this process include 225,925.902 kg/hr superheated steam, compressed air 235.133 kg/hr, 194,409 kg/hr water from Nandra Krenceng Reservoir, 20,100 kg/hr ethylene and kg/hr 6,500 ethylene glycol as refrigerant. The number of workers required is 154 workers. From the economic analysis, the results obtained that the total capital investment (TCI) required amounted to IDR 2,137,702,878,472.42 and working capital amounted IDR 1,191,682,574,203.57. For full capacity, the Pay Out Time during the year 2.2, Rate of Investment of 44.68%, Breakeven Point of 13.82%, Shutdown Point of 7.68% and Discounted Cash Flow of IDR 1,750,852,326,748.65. From this economic review, capacity of 33,000 tons per year is feasible to be established in Indonesia.