湿容量在烧结混合料制粒中的应用

Application of the Moisture Capacity in the Granulation Process of Sintering Mixture

优化制粒是烧结生产中提高产量和质量,降低能耗的重要措施。水分控制是制粒生产中的重要环节,它影响到制粒颗粒的强度和粒度组成,决定了生料层的透气性。为提高制粒生产中加水量的控制水平,文章对湿容量在铁矿石烧结生产中的应用作了相关研究。物料湿容量是指单位质量的烘干物料在一定温度和压力下所能容纳的最大含水量。实验室试验及工业试验表明:①物料的吸水过程规律显著,湿容量是物料重要的吸水特性参数;②湿容量与物料制粒的适宜含水量成线性关系,相关系数R=93.1%;③可通过物料的CaO、Al2O3、MgO、<0.2mm的粒级含量及0.2～0.7mm的粒级含量等理化指标来预测湿容量。为提高湿容量的预测效果,比表面积、孔隙率、接触角等物性参数的影响也必须加以考虑。

Optimizing granulating is an important method to improve the output and quality of the sintering production and to reduce energy consumption. Moisture control, the vital step in process of granulating, affects the strength and size of the granule, thus determines the raw mix bed permeability. In order to improve the control level of water addition in the granulation, this paper presents some related work about the application of the moisture capacity in iron ore sintering production. The moisture capacity refers to maximum water content allowed for unit mass of dried material at a given temperature and pressure. Laboratory test and industrial experiment show that： 1 ） there is a significant rule for water absorption of the materials, moisture capacity is an important parameter for water absorption of materials; 2） it is a linear relationship between moisture capacity and the optimal water content, the correlation coefficient R = 93.1% ; 3） moisture capacity can be predicted via the physical and chemical parameters, like the percentage of CaO. A1203 . MgO, as well as the percentage of particles with size below 0.2 mm and size between 0.2 mm to 0.7 ram. In order to increase the prediction accuracy of moisture capacity, the influence of some parameters like specific surface area, porosity, contact angle, and so on, should be taken into account.