Green Assessment Method for Industrial Technology: A Case Study of the Saline Lake Industry

The sustainable utilization of the resources of the saline lake requires green technology applications, but now, the comprehensive evaluation methods to assess the sustainability of technology in the saline lake industry field are scarce. In this study, a model for assessing green technologies, reflecting elements of techno-economic evaluation, material flow analysis, life cycle assessment, eco-efficiency, circular economy, etc., is developed for assessing technology on technical, economic, and environmental aspects, comparing the technology of bischofite, a by-product of potash production, to fused MgO (target case) and magnesite to fused MgO (reference case) as the target to design three cases, namely, the target case, reference case, and blank case. The results show that in terms of comprehensive technology evaluation, the score of the target case is 70, slightly better than the reference case technology, which is reflected in better energy, water output rate, general industrial solid waste comprehensive utilization rate, etc. With regards to the environmental impact, the eco-efficiency value of the target case is 15.79 and the reference case is 4.03 owing to less SO2, CO2, and NO X emissions through the life cycle of the utilization of bischofite to fused MgO despite the fact that the net present value (NPV) of the target case (117 $/t pro.) is lower than that of the reference case (315 $/t pro.). Therefore, we conclude that the target case is superior to the reference case according to our multiple evaluation perspectives of economic, environmental, and technological considerations. The evaluation method can be more widely applied to the comparison of different technologies, especially in resource extraction, environmental protection, waste utilization, etc.