用后镁碳砖再生工艺的生命周期评价和能耗分析

基于生命周期评价（LCA）方法量化分析用后镁碳砖再生工艺过程中资源/能源消耗、污染物排放和环境影响潜力，其中用后砖再生料的添加比例控制在70%左右，电熔镁砂和石墨为配料。结果表明，生产1吨再生镁碳砖中全球变暖潜值最大，约1.45×103kg CO2 eq.，矿产资源耗竭、化石能源耗竭和人类非致癌毒性潜值较大，分别为7.20×102kg Cu eq., 3.49×102kg oil eq.和2.94×102kg 1,4-DCB eq.。归一化后的总环境影响为3.12，相对损害最大的影响为人类非致癌毒性，主要是生产过程中电力需求大造成；相对损害最大的生产单元过程是配料电熔镁砂和鳞片石墨的生产阶段，贡献了1.76，其次是原料加工、原料再生料的生产，分别贡献1.01和0.12，坯体制备、热处理和成品加工仅贡献了少量环境影响。

Life cycle assessment and energy consumption analysis of regeneration process of used magnesia carbon bricks

Based on the life cycle assessment (LCA) method, the resource/energy consumption, pollutant emission and environmental impact potential of used magnesia carbon bricks are quantified. The add proportion of used brick as raw material is controlled at 70%, and fused magnesia and graphite are used as ingredients. The results show that the global warming(GWP) is the largest in the production of 1 ton of recycled magnesia carbon bricks, which is 1.45×103kg CO2 eq., and the potential values of mineral resource depletion (SOP), fossil energy depletion (FFP) and human non-carcinogenic toxicity (HTPnc) are large, which are 7.20×102kg Cu eq., 3.49×102kg oil eq. and 2.94×102kg 1,4-DCB eq., respectively. After normalization, the total environmental impact is 3.12, and the impact of HTPnc with the largest relative damage is mainly caused by the large power demand in the production process. The production unit processes with the greatest relative damage are the production stage of fused magnesia and flake graphite, contributing 1.76, followed by raw material processing and raw material recycling, contributing 1.01 and 0.12, respectively. Blank preparation, heat treatment and finished product processing only contribute a small amount of environmental impact.