Case study of a novel low rank coal to calcium carbide process based on techno-economic assessment

As calcium carbide (CaC2) production is an energy-intensive industry, a novel low rank coal to CaC2 (LRCtCC) process has been developed. This study is aimed to evaluate the techno-economic performance of the LRCtCC process. A model integrating particle swarm optimization and nonlinear programming (PSO-NLP) is developed to predict the behavior of coal pyrolysis. The techno-economic assessment of the LRCtCC process is analyzed. Results show that the power consumption of electric arc furnace is expected to drop to 2845 from 3169 kW·h/t with the hot material (HM) temperature increasing from 25 to 850 °C. The effect of increasing HM temperature is greater than that of adjusting the composition of fuel on system efficiency, cost of CaC2, and internal rate of return. In addition, the effects of typical economic factors on net present value (NPV) of the LRCtCC process are compared. Results show that variations of CaC2 price and power consumption pose a remarkable impact on NPV. The findings of this study suggest that the LRCtCC process would be an attractive method for the improvement of CaC2 production. •A PSO-NLP model was developed to predict the behavior of coal pyrolysis.•The effect of hot material temperature on the power consumption of CaC2 production was investigated.•The application of rotary hearth furnace gas and electric arc furnace gas was studied.•Sensitive analysis of the main parameters on economic performance was evaluated.