Optimization and sensitivity analysis of a multi-product solar grade silicon refinery: Considering environmental and economic metrics.

Abstract

[EN]Today, one of the main lines of solar energy development is the creation of environmentally friendly, waste-free and inexpensive solar grade silicon production technologies. Presently, the main solar grade silicon production technologies are based on the reduction of silicon hydrogen chloride compounds (trichlorosilane, tetrachlorosilane and silane). This paper will examine the results of the optimization of a multi-product silicon refinery, where the objective functions are Profit and Eco-indicator99. Seven scenarios are considered for the work. The best scenario (S4) showed a tendency to maintain a balance between Profit (98.66 M$/y) and the environmental indicator Eco99 (6.04 MP/y). Similarly, a sensitivity analysis was carried out by varying the market prices of each of the products obtained (solar grade silicon, TEOS at different purities, and chlorosilanes) with an increase of 10% and a decrease of 10%, resulting in multiple production scenarios depending on what the market dictates. By increasing the cost of solar grade silicon by 10%, the multi-product refinery achieves the highest profit (151.84 [M$/y] with an environmental impact of 9.8 [MP/y]), and by decreasing the cost of the same silicon by 10%, the lowest environmental impact is achieved (36 [M$/y] with an environmental impact of 3 [MP/y])