4E analyses of a novel multi-generation system based on methanol-steam reforming integrated with scramjet multi cooling cycle and ammonia synthesis

Abstract

A state-of-art multi-generation plant integrated with a scramjet multi-cooling cycle for power, hydrogen, ammonia, and freshwater generation was analyzed from an energy, exergy, exergoeconomic as well as environmental (4E) standpoint. The coolant of the cooling cycle was the fuel of the scramjet cycle and in terms of optimizing consumed power, this cycle is benefiting from four-stage compressors. To improve the rate of hydrogen production, a methanol steam reforming procedure was employed. To provide fresh water, a reverse osmosis membrane was employed and integrated into the plant. To consider the powers of input design variables on the implementation criteria of the plant and reduce CO and CO2 emission, an exhaustive parametric investigation was performed. The thermodynamic efficiencies, the sum unit cost of the products, the system emission rate, and the environment penalty cost rate as well as values of the products as the multi-generation plant's performance criteria were computed. Raising the hydrogen mole fraction caused an increase in the emission rate.