Life cycle environmental impact assessment of borax and boric acid production in China

Borax and boric acid are important primary products in China's boron industry. Their characteristic production technology has been adapted to the low ore grade. To analyze the environmental impacts of different borax and boric acid production processes and to promote cleaner production of boron industry, the life cycle assessment method of cradle-to-gate was applied in this study. GaBi4.4 software was used in the assessment and the environmental impacts were classified according to the CML2001 method. To show the degree of consumption of mineral resources and energy respectively, the abiotic depletion potential was divided into the mineral resources depletion potential and fossil energy depletion potential. A comparison between the mineral processing and entire system studied shows that energy consumption is important in life cycle environmental impacts. Boron production industries should refrain from using coal as their main heat source and try to use clean energy. A comparison between the borax production processes shows that the boron-rich slag is the cleanest material and that blast furnace gas can be used to reduce environmental impacts further in slow cooling link. A comparison between the boric acid production processes shows that flotation (I) is the cleanest process with the material of szaibelyite. Ludwigite should be processed after dressing to reduce the environmental impacts. Boron concentrate can be used to produce borax or boric acid as an alternative to szaibelyite but feasible production processes are still the focus of future research. (C) 2013 Elsevier Ltd. All rights reserved,