南方离子吸附型稀土企业温室气体排放核算方法研究

Study on the accounting method of greenhouse gas emission of ion absorbed rare earth enterprises in South China

南方离子吸附型稀土企业是工业企业主要的温室气体排放源之一,对于我国碳达峰具有重要影响。国家层面尚未公布南方离子吸附型稀土行业统一的核算方法,温室气体排放核算边界、范围、方法有待进一步明确,制约了国家对其温室气体排放的研判和认识。从燃料燃烧、过程排放、净购入电力和热力四个方面建立了南方离子吸附型稀土产业链上三种不同类型企业,即稀土矿山企业、冶炼企业、金属及合金企业的温室气体排放核算方法。通过分析案例企业情况可知,电力消费是三种类型企业的最主要温室气体排放源,单位产品温室气体排放量按从大到小排序为金属及合金企业、冶炼企业、稀土矿山企业。生产过程中草酸分解排放、阳极效应排放也是稀土企业温室气体重要的组成部分;降低单位产品的电力消耗,特别对于金属及合金企业而言,是未来稀土产业温室气体减排的重点方向;减少草酸和阳极电极的使用也是南方离子吸附型稀土企业减少温室气体排放的优化路径之一。

Ion adsorption rare earth enterprises in South China are one of the main sources of greenhouse gas emissions of industrial enterprises,which has important influence on peak carbon emissions.The unified accounting method of greenhouse gas emission accounting for the ion adsorbed rare earth enterprises in South China has not been published at the national level,and the boundary,scope and method need to be further clarified,which restricts the country’s judgment and understanding.Establishes the accounting methods for greenhouse gas emissions of three different types of enterprises in ion-adsorption type rare earth industry chain,namely rare earth mining enterprises,smelting enterprises,metal and alloy enterprises,from the perspectives of fuel combustion,process emissions,net purchase of electricity and heat.The analysis of case enterprises shows that power consumption is the main source of greenhouse gas emissions of three types of enterprises,and the order of greenhouse gas emissions per unit product is metal and alloy enterprises,smelting enterprises and rare earth mining enterprises.Oxalic acid decomposition emission and anode effect emission in the production process are also important components of greenhouse gases in rare earth enterprises.Reducing power consumption per unit of product,especially metal and alloy enterprises,is the key direction of greenhouse gas emission reduction in the rare earth industry in the future.And reducing the use of oxalic acid and anode electrodes is also one of the optimal paths for ion absorbed rare earth enterprises in South China to reduce greenhouse gas emissions.