Techno-Economic Analysis of Electric Boiler Integration for Direct Steam Generation in Ethylene Plants

This study proposes a steam generation system using electric boilers to use in an ethylene plant. It focuses on the effect of producing medium and low-pressure steam using electric boilers that are powered using renewable energy instead of producing high pressure steam using steam turbines that result in steam loss. The main parameter studied is the cost affiliated with this design. First, the cost difference between generating renewable energy and importing it is studied. It is found that generating renewable energy using wind ($0.081/kWh) and photovoltaic (PV) systems ($0.090/kWh) is more economical, while concentrated solar power (CSP) is significantly more costly at $0.237/kWh. In addition, sensitivity analyses were conducted to study the effect of the percentage loss from the condenser and the import cost of the renewable energy on the total cost. It was found that both parameters have a linear relation with the overall cost. When the import cost increased from $0.08/kWh till $0.2/kWh, the total cost increased by $0.12/kWh. Moreover, when the percentage loss increased from 1% to 10%, the total cost increase was minor, however, the increase in makeup water was 26,000 kg/hr.