Ecological sustainability assessment of building glass industry in China based on the point of view of raw material emergy and chemical composition

Severe environmental destruction is being driven by excessive resource consumption in the industrial production process. Therefore, there is a necessity to evaluate the sustainability of the production system. In this study, the emergy method has been adopted to assess the flat building glass production in China based on raw material and chemical composition. A series of problems including key contributors, primary sustainable indexes, unit emergy value (UEVs), sensitivity ratios, and waste impact was studied. The results illustrate that (1) the nonrenewable resources and imported resources showed the dominant impacts. (2) Silica sand and sandstone were the foremost items for the raw material angle emergy. (3) Excessive EIR, serious ELR, and tiny ESI were the main contributors to the unsustainability of the evaluated system. (4) Four UEVs were revealed, which are 1.69E + 12sej/kg, 1.80E + 12sej/kg, 1.60E + 12sej/kg, and 1.71E + 12sej/kg, respectively. (5) The nonrenewable resources showed the biggest fluctuation (7.09%), followed by imported resources (1.62%) in view of the raw material perspective; for the chemical composition, the nonrenewable resources were 7.15%, and imported resources were 1.49%, respectively. (6) Waste gas emissions were found as the major emergy contributor to the economic loss. Furthermore, positive solutions were discussed for improving the sustainability of glass production, including the proportion increase of renewable energy, recycling material replacement, and promotion of energy-saving equipment.