田家村半自磨产品粗粒矿浆长距离管道输送参数优化

Parameter Optimization on Long Distance Pipeline Transportation of Coarse Ore Pulp from Semiautomatic Grinding in Tianjia Village

白马铁矿田家村半自磨产品设计采用6.5 km管道输送至磨选厂房,输送粒度为-3 mm,投产后管道经常堵塞,不能正常运行。为此,首先开展了矿浆粒度、流量、浓度、流速等输送工艺参数考察,结果表明:出口矿浆粗粒级减少、细粒级增加,输送过程中流量、流速下降,浓度上升形成堵塞;在此基础上,对输送系统进行了优化改造:调整半自磨筛板筛孔参数为2.5 mm×12 mm,一级泵叶轮直径由965 mm改为990 mm,将泵池结构由平底四角改造为三面坡结构,改造后输送系统运行平稳。为尽可能提高半自磨机处理能力,对优化后半自磨参数、矿浆管道粒度,矿浆流量、流速进行了考察,结果表明:优化后输送矿浆浓度得到提升、输送流量、流速超过了设计指标,确保了管道输送的稳定。为探讨输送系统进一步优化的可行性,开展了矿浆流变特性试验研究,试验了原矿浆体沉降特性、不同浓度矿浆的流变特性、临界流速,分析计算了摩阻损失,在综合分析浓度、粒度等参数对输送影响的基础上,将筛板尺寸调整为2 mm×12 mm,将一级泵站2台泵叶轮分别调整为870 mm和980 mm。输送系统参数优化后,半自磨台时平均613 t/h,管道流速3.44 m/s,实现了粗粒矿浆长距离管道输送稳定运行,对矿山企业管道输送有借鉴意义。

The semi-automatic grinding products of Baima Iron Mine in Tianjia Village were transported to the grinding plant by 6.5 km pipeline,which conveying particle size was-3 mm.Due to unreasonable design parameters at the initial stage of production,the pipeline was often blocked and cannot run normally.Through the analysis of the granularity,flow rate and velocity of ore pulp,some researches and improvements were carried out.The results show that the coarse particle size of export pulp decreases and the fine particle size increases,and the flow rate and velocity decrease and the concentration increase to form blockage in the conveying process.On this basis,the conveying system was optimized and transformed:the mesh parameters of the semi-autogrinding-sieve plate were adjusted to 2.5 mm×12 mm,the diameter of the impeller of the first stage pump was changed from 965 mm to 990 mm,the pump pool structure was transformed from flat bottom four corners to three-sided slope structure,and the conveying system ran smoothly after the transformation.In order to improve the processing capacity of semi-autogenic mill as much as possible,the parameters of semi-autogenic mill after optimization,slurry pipe size,slurry flow rate and velocity were investigated.The results show that the slurry concentration is improved after optimization,and the conveying flow rate and velocity exceed the design indexes,ensuring the stability of pipeline transportation.To study the feasibility of conveying system to further optimize and carry out the experimental study of the rheological properties of the pulp,test the original pulp body sedimentation characteristics,different concentrations of the rheological properties of pulp,the critical flow velocity,friction loss are analyzed and calculated by the comprehensive analysis on the impact of parameters such as concentration,particle size on transport,on the basis of adjust sieve plate size for 2 mm×12 mm.Adjust two pump impellers of the first pump station to 870 mm and 980 mm respectively.After optimizing the parameters of the conveying system,the average time of the semi-automatic grinding platform is 613 t/h,and the flow rate of the pipeline is 3.44 m/s.It realizes the stable operation of the long-distance pipeline conveying of coarse slurry,which is of reference significance to the pipeline conveying of mining enterprises.