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Summary Carbon dioxide conversion into beneficial products has received very much attention in recent years to decrease industrial CO2 emissions. In this context, integration of gas to liquids (GTL) process with an iron‐based Fischer‐Tropsch (FT) reactor with ammonia and urea synthesis plants was investigated. The main motivation of the proposed integration is to reuse a released CO2 stream from the GTL process and to enhance the commercial process economy. The required hydrogen for ammonia comes from polymer electrolyte membrane (PEM) electrolyzers running by solar power. Latin hypercube design (LHD) approach was applied to model the profitability and carbon efficiency of the process. Optimization was conducted to maximize the carbon efficiency and profit index of the overall process using the model‐based calibration (MBC) toolbox of MATLAB. The results demonstrated that at the optimum case, the proposed integration is capable of producing 48 t/h of urea and also utilizing about 35 t/h of CO2 produced in the GTL process. The results were compared with another configuration in which a cobalt‐based FT reactor was integrated with ammonia and urea processes. The results suggest that profitability, carbon efficiency, and urea production of the process configuration with a Co‐based FT reactor is higher than the iron‐based configuration while the wax production rate of the iron‐based configuration is higher than that of the Co‐based process. Techno‐economic feasibility study of the zero CO2 emission process represents that the carbon efficiency of around 100% could be obtained.

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The performance improvement of a manufacturing system is a major component of maintaining the position of a company in the present competitive world. In the present dynamic environments and complex markets and based on the responding time significance, the optimisation of the performances has become a vital factor for the companies and their competitive. In this paper, simulation software is applied to evaluate the process of water pump manufacturing in Iran Godakht Company, in order to determine the barriers present in supplying the final customers with their needed products, and then some suggestions are offered to meet these barriers. To do so, the production process was assessed. Then their time distribution was determined for the simulations. In the next step, the ARENA Software was utilised to perform the modelling of the manufacturing process and based on the results, three new scenarios were introduced, and finally, multi-criteria decision-making approaches were applied to select the optimised scenario.