A novel zero-emission process for the co-production of power, natural gas liquid, and carbon dioxide based on shale gas

Abstract

This paper presents an integrated process with three products, namely carbon dioxide, power, and natural gas liquid, from the pollutant shale gas. The proposed system utilizes all shale gas for product generation, contributing to the zero CO2 footprint. The hydrocarbon recovery is performed through cold energy integration. An Aspen HYSYS code simulates the system to assess the 4E analysis. Results showed that the proposed structure's first and second laws efficiencies are 51.29% and 80.54%, respectively. This process includes natural gas liquids recovery unit, Allam power cycle, steam power cycle, NH3 power cycle, and ammonia-water power cycle. Exergy analysis illustrated that the largest exergy destruction, valued at 392.15 MW (a 52.81% contribution), happens in the absorption power cycle. Among all equipment, the combustion chamber has the highest exergy destruction. The environmental analysis revealed that the proposed process has zero carbon emission and 4866 tons of CO2 is produced. In the natural gas liquid recovery unit, due to the employing separation with a turboexpander, good refrigeration is provided for the shale gas, which results in the maximum hydrocarbon recovery of 4163 barrels/day. Moreover, besides providing all the power requirements of pumps and compressors, the proposed process generates 460.60 MW of power with a production cost of 8.36 $/MWh.