Evaluation of GHG emissions from the production of magnesia refractory raw materials in Dashiqiao, China

Greenhouse gas (GHG) emissions from the industrial sector are rapidly increasing in China. As the largest producer of magnesia-refractory raw materials in the world, the production of magnesia-refractory raw materials in Dashiqiao city causes severe environmental problems, such as greenhouse gas emissions, air pollution and high energy consumption. As Dashiqiao's pillar industry, the production of magnesia refractory raw materials has become a serious obstacle to its sustainable development. At present, most studies are mainly focused on the greenhouse gas emissions from magnesium production and the emissions from magnesia refractory raw material production have not been thoroughly investigated. This research addresses this important information gap. This study focuses on the carbon emissions from the production of five kinds of magnesia refractory raw material products. The results demonstrate that the estimated greenhouse gas emissions are 2.7 t CO2eq/t of caustic calcined magnesia, 3.1 t CO2eq/t of general dead-burned magnesia, 4.7 t CO2eq/t of middle grade dead-burned magnesia, 4.7 t CO2eq/t of single-phase process fused magnesia, and 7.8 t CO2eq/t of two-phase process fused magnesia. In 2014, the five production chains of the main magnesia refractory raw materials in Dashiqiao released 13.76 million t GHGs, in which the single-phase process fused magnesia accounted for 24%, while the caustic calcined magnesia and the middle grade dead-burned magnesia for 23% and 23%, respectively. As one of the most important magnesia producer and supplier, the magnesia related industry in Dashiqiao has emitted large amounts of GHGs during the past 90 years, resulting in a significant contribution to global warming potential and negative impacts on urban sustainable development. Therefore, the city needs the magnesia industry to make structural adjustments and technical improvements.