Optimization Process of an Air Dense Medium Fluidized Bed Separator for Treating High-Ash Non-coking Indian Coal

The performance of an air dense medium fluidized bed separator, used for coal cleaning, is significantly affected by the operating process parameters. Proper estimation of these parameters is of great importance from both operational and control standpoints. The existing literature reveals that the optimum operating range for these parameters has been experimentally determined by pursuing a traditional “one variable at a time approach” which fails to consider parameter interactions and sometimes misleading, especially when the behavior of two process parameters changes as a function of a third parameter. It is realized that the interrelationship among these process parameters have a significant effect on the overall performance of this separator. In this study, a detailed investigation is carried out to examine the interdependencies among these parameters and their interactional effect on the separation performance of an air dense medium fluidized bed separator. Response surface methodology is used for this purpose and empirical models for two key response parameters, namely, product ash content and combustible recovery, are developed. These empirical models are utilized to establish the new levels of the parameters to achieve the optimum performance of the equipment and subsequently these model predictions are validated against the experimental results. Preliminary results show a strong interaction among some operating parameters.     

碱性体系浸出废铅膏中的铅

利用碱性体系浸出废铅膏中的铅,分别探究了浸出时间、温度、NaOH浓度及固液比对铅浸出的影响。在单因素最佳条件下,通过Box-Behnken响应面优化探究了这4种因素对铅浸出的交互影响,经验证试验得到最佳浸出条件,并对最佳条件下浸出后的剩余固体做检测分析。结果表明,铅的最佳浸出条件为:浸出时间33 min、浸出温度75℃、NaOH浓度7 mol/L、固液比43(g/L);最佳条件下的铅浸出率为56.35%,浸出浓度为17.33g/L,浸出后剩余固体主要为PbO2,可回收提纯后直接利用。     

新钢3000mm中板生产线技术改造与品种优化

介绍新钢3 000 mm中板线技术改造的装备特点、生产工艺状况及改造后的品种结构优化效果,并对采用的新技术进行了论述。     

Optimization of Friction Welding Process Parameters for Joining Carbon Steel and Stainless Steel

 Friction welding is a solid state joining process used extensively currently owing to its advantages such as low heat input, high production efficiency, ease of manufacture, and environment friendliness. Materials difficult to be welded by fusion welding processes can be successfully welded by friction welding. An attempt was made to develop an empirical relationship to predict the tensile strength of friction welded AISI 1040 grade medium carbon steel and AISI 304 austenitic stainless steel, incorporating the process parameters such as friction pressure, forging pressure, friction time and forging time, which have great influence on strength of the joints. Response surface methodology was applied to optimize the friction welding process parameters to attain maximum tensile strength of the joint. The maximum tensile strength of 543 MPa could be obtained for the joints fabricated under the welding conditions of friction pressure of 90 MPa, forging pressure of 90 MPa, friction time of 6 s and forging time of 6 s.     

微波强化焙烧氧化锌烟尘提铟工艺优化研究

以锌冶炼过程产生的氧化锌烟尘为原料,采用微波硫酸化焙烧—水浸工艺提取铟。采用响应曲面法(RSM)对焙烧过程进行优化,以铟的浸出率为响应指标,选取焙烧温度、酸矿比、焙烧时间为考察因素,采用Box-Behnken Design(BBD)设计方案以三因素三水平设计试验,得出最优化的焙烧工艺条件,并获得拟合度高的二阶多项式模型。结果表明,微波硫酸焙烧氧化锌烟尘的最佳工艺条件为:焙烧温度208℃、酸矿比0.5(mL/g)、焙烧时间93min;在最佳焙烧条件下,铟浸出率模型预测值为92.89%,试验真实值为92.78%,模型可用于预测微波硫酸化焙烧氧化锌烟尘提铟的工艺。     

响应曲面优化微波干燥铅渣的工艺研究

采用微波加热技术对铅渣进行脱水。通过响应曲面法中心组合设计分析了干燥温度、干燥时间、物料厚度对脱水率的影响,并建立了相关的数学模型。方差分析表明,二次方数学模型拟合较好,物料厚度、干燥温度对脱水率的影响较干燥时间更为显著。优化工艺参数为干燥温度93℃,干燥时间10min,物料厚度19mm,相对脱水率达到68.21%,实际值与模型预测值相差0.73个百分点,干燥后铅渣的含水量为8.12%,可以满足后序工艺要求。     

Particle Classification Optimization of a Circulating Air Classifier

ABSTRACT

Undoubtedly, wet processing of ores requires huge quantity of water. This provides enough incentive for dry beneficiation of ores which has great promise predominantly from an environmental standpoint and water scarcity in the mining and processing industries. Therefore, the present investigation made an attempt to effectively address the issues related to dry classification of minerals. In this study, a three-factor-three-level Box–Behnken factorial design combined with response surface methodology (RSM) was employed for modeling and optimization of operational parameters of a circulating air classifier. The three main operating parameters studied were air flow rate, feed rate, and guide vane angle. The primary and interaction effects of operating variables were evaluated using RSM while generating the second-order response functions for both the responses, cut size and size selectivity increment. The values of cut size and size selectivity increment obtained using predictive models were in excellent agreement with the observed values. The optimization of these predictive response models resulted in the optimal values of air flow rate, feed rate, and guide vane angle for achieving better classification efficiency. This study establishes that the Box–Behnken factorial design combined with RSM effectively model the performance of circulating air classifier.     

多孔介质模型在稀土电解槽优化模拟中的应用

针对熔盐电解法制取稀土金属钕槽型结构,首次提出了多孔介质模型与表面化学反应相结合的方法研究阳极电解反应过程,通过在靠近阳极表面取1~2mm的薄层设立为多孔介质层,并在多孔介质层上增设化学反应,模拟研究阳极表面的化学反应、槽体内部流场运动情况以及气泡上浮过程,同时对比欧拉法的模拟结果得到了该模拟法与欧拉法模拟的区别及该法研究的优势。模拟结果表明,该方法更能反映实际电解过程气泡生成和运动规律。     

响应曲面法优化铝电解废阴极碱熔提纯工艺

通过响应曲面法优化铝电解废阴极碱熔提纯工艺过程。基于Box-Behnken Design（BBD）设计,研究了温度、时间、初始碱料比对废阴极碱熔除杂效果的影响,获得了影响因素与碱熔渣碳含量之间的二次数学模型,确定了碱熔脱杂最优工艺参数：碱熔温度550 ℃、碱熔时间180 min、初始碱料比2,此条件下碱熔渣碳含量95.47%,与预测值相差0.61个百分点。试验值与模型预测值相近,表明该模型可用于优化废阴极碱熔提纯过程。     

优化中厚板生产计划管理的实践

本文对新余钢铁股份有限公司中板生产线在生产计划安排上遇到的问题进行了分析,提出了改进措施,并对改进后的使用效果进行了评价。     

用废合金回收碳化钨制造硬质合金的工艺优化试验

用电子探针检测手段对比了回收碳化钨和一般碳化钨的不同特性,从回收碳化钨具有结晶完整、晶内缺陷少、化合碳充足等优良性能出发,用工艺优化手段弥补回收碳化钨氧含量高、夹杂物多等缺点,试制出了性能优于用一般碳化钨生产的硬质合金。     

焦家金矿磨矿介质配比优化试验研究与应用

针对焦家金矿选矿厂球磨机单位球耗高、磨机效率偏低和磨矿产品粒度组成不均匀等问题,基于矿石力学性质和磨矿循环产品粒度分布,采用段氏球径半理论公式计算得到推荐方案介质配比,并建立对照方案进行实验室磨矿对比试验,最终确定初装球方案为:Φ90:Φ70:Φ50:Φ40:Φ30=15:25:20:15:25.2016年10月26日...     

济钢中板厂生产工艺的优化

本文介绍了济钢中板厂为实现与新建中厚板厂产品结构的互补，加速产品的低成本生产与升级、增强产品的竞争力，在对本厂的技术装备、工艺条件进行系统分析后，采用超级钢开发的先进技术思想，结合本厂控轧控冷系统的不断完善，着重进行了以四辊轧机为中心、机前机后控温为手段、轧后加速冷却为保障的多种生产模式的工艺完善与优化。     

甲酸—硝酸还原浸出低品位软锰矿

用甲酸为还原剂在硝酸体系中浸取低品位软锰矿,通过单因素试验和响应面法考察了甲酸用量、硝酸浓度、液固比、反应时间和反应温度对锰、铁、铝浸出率的影响。结果表明,当甲酸用量一定时,影响锰浸出率的因素主次依次是液固比、硝酸浓度、反应时间和反应温度。当甲酸用量为3 mL、硝酸浓度0.45mol/L、液固比5.6、反应温度90℃、反应时间2.5h时,锰、铁和铝的浸出率分别为91.01%、43.06%、21.61%。     

中心组合设计优化SG-5型PVC稀土复合热稳定剂的研究

采用正交设计与中心组合设计法优化了以硬脂肪酸镧、硬脂肪酸高铈、硬脂肪酸钕为复合热稳定剂的配方,得到了这三种稀土化合物对SG-5型PVC热稳定性产生作用的响应面图,探讨了稀土金属离子对PVC的稳定机理;检测了产品的性能。优化结果表明,以SG-5型PVC0.5g、硬脂肪酸镧为0.013g、硬脂肪酸钕0.0196g及硬脂肪酸高铈0.02g所组合得到的PVC树脂,其热稳定温度达到183.3℃,并能稳定35分钟以上,比正交实验结果180.8℃提高2.5℃,其力学性能优于正交结果。La3 、Ce4 、Nd3 对PVC树脂的热稳定作用与它们离子半径的大小及与自由基成键的能力和吸附能力呈正相关性。     

响应面法优化从电解锰阳极液中回收硒工艺

采用响应面设计优化铁炭微电解法回收电解锰阳极液中硒的工艺条件,研究搅拌速率、铁炭比和反应时间对硒回收率的影响。结果表明,各因素对硒回收率的影响大小顺序为:搅拌速率>铁炭比>反应时间,三者之间两两的交互作用均较弱。最优工艺条件为:搅拌速率199r/min、铁炭比1.94g/g、反应时间192min。在此条件下,硒的回收率可达到96.34%,与模型预测值96.52%无显著差异。     

酒钢CSP流程SPCC钢LF精炼渣-钢平衡及渣成分优化

 利用热力学计算软件FactSage确定了精炼渣中MgO质量分数合理范围为4%~8%,以6%最佳。由工业取样结果结合FactSage分析了1873K时SiO2-CaO-Al2O3-6%MgO准三元系液相区及CaO饱和的固液两相区渣-钢平衡。结果表明:高碱度高w(CaO)/w(Al2O3)(C/A)精炼渣有利于钢液的低氧低硫和低硅控制,但并非造得越“白”越好,相反过高的CaO对脱氧和硅含量控制不利。通过钢渣平衡分析得到了酒钢SPCC精炼渣优化成分范围(质量分数)为：CaO为50%~55%,Al2O3为30%~36%,SiO2为1%~6%,MgO为4%~8%,6%为最佳,碱度为9.0~14.0,w(CaO)/w(Al2O3)为1.5~1.8,实验室渣-钢平衡试验和工业生产结果均验证了优化的渣系较原渣系精炼效果更加优越,能够同时降低钢中总氧、硫和硅含量,也能有效控制钢中夹杂物的成分。     

韶钢3450 mm中厚板产线矫直机辊面缺陷的工艺改进

针对韶钢3 450 mm中厚板生产线由于矫直机辊面缺陷造成的大量故障停时问题,对矫直机矫直辊辊面缺陷情况进行跟踪,将辊面缺陷分成三大类,并对每种类型缺陷产生的原因进行详细分析,指出每类缺陷产生的根本原因,提出工艺改进措施。通过系列工艺改进措施,将矫直机辊面缺陷造成的工艺故障停机时间减少近90%,大大缩短了修磨时间和降低了工作强度。     

包钢350km/h钢轨用连铸坯的生产工艺优化

文章根据包钢炼钢厂生产350 km/h铁路钢轨用连铸坯的生产实践,分析了350 km/h铁路钢轨用连铸坯炼成率低的原因,通过采取相应的措施使350Km/h铁路钢轨用连铸坯合格率大幅提升,满足了生产需要。