离子型稀土冶炼环境治理与工艺优化

Environment governance and process optimization of ion-adsorbed rare earth smelting

2011年10月1日起实施《稀土工业污染物排放标准》,新标准的实施对稀土冶炼生产的三废排放提出了更高的要求,文章结合南方某离子型稀土冶炼厂的环境治理现状,提出了三废治理的优化方案:优化废气治理工艺,提高酸雾吸收塔氯化氢吸收率,采用水膜除尘设施烟尘、提高二氧化硫的去除效果;优化废水治理工艺,将生产废水进行分类收集,对含重金属、钍、铀废水进行车间排口治理,对草酸沉淀上清液进行草酸、盐酸回收;对固体废弃物进行分类收集,并根据相关规定妥善处置;噪声治理,生产设备首先选用低噪声设备,其次采用消声、隔声、减震等措施.相关监测数据表明:废气、废水、噪声符合《稀土工业污染物排放标准》及其它相关标准污染物排放浓度限值要求.低放射性固体废物按规定建库集中堆放,危险固体废物累积一定数量后由有资质单位运输、处理,其它废渣按国家相关管理办法规范治理.

Emission Standards of Pollutants from Rare Earths Industry has been implemented since October 1, 2011 which puts forward higher standard for wastes emission （waste gas, waste water, waste residue and noise） of rare earth smelting plant. Optimum proposal is presented in accordance with environmental management status quo of an ion-adsorbed rare earth smelting plant in southern China： hydrogen chloride absorptivity of the acid mist absorption tower, as well as the removal efficiency of soot and sulfur dioxide of the water film dust removal installation are improved to optimize waste gas treatment technology; industrial waste water is separately collected, workshop drainage exits of the waste water containing heavy metal, thorium and uranium are governed, and supernatant in oxalic acid precipitation is recycled to optimize waste water treatment technology; waste residue is separately collected and dealt with according to relevant regulation; low noise equipments are preferred and measures, such as noise elimination, sound insulation and damping are taken to treat noise. Relevant monitoring data indicates that waste gas, waste water and noise meet the requirement of emission concentration of Emission Standards of Pollutants from Rare Earths Industry and other related standard. Warehouses are set up to stack low-level radioactive solid wastes which are transported and dealt with by qualified units after accumulating to certain amount, and other waste residues are governed in accordance with relevant administrative measures.