瓮福磷矿选矿试验及选矿厂生产调试

介绍了瓮福磷矿英坪矿段磷块岩富集的反浮选法和焙烧－消化－分级法的小试验、扩大试验指标，以及捕收剂代用的试验结果，重点介绍了选矿厂生产调试的浮选流程、药剂用量、生产设备和试生产指标。     

瓮福磷矿穿岩洞矿段磷矿石选矿研究

对瓮福磷矿穿岩洞矿段混合磷矿石进行了直接浮选、单－反浮选、反－正浮选和正－反浮选４种工艺流程的选别试验,结果表明,采用正－反浮选和反－浮选工艺处理该磷矿石,均可取得较好的试验指标。综合评价推荐的流程是正－反浮选流程。     

瓮福磷矿选矿厂精矿仓设计

瓮福磷矿选矿厂精矿仓首次采用网架式地面矿仓，造价低，空间利用率高，设备运行平稳可靠，操作灵活方便，工作环境好。超长梭式胶带布料机的设计也是成功的。     

瓮福磷精矿制取湿法磷酸评价试验

介绍瓮福磷精矿的物化性质,并通过反应活性试验,发泡性能试验及工艺条件试验对该矿制取二水物磷酸进行评价。     

瓮福磷矿a层矿和b层矿的混合选矿实践

瓮福磷矿a层矿为沉积型硅钙质磷块岩,b层矿为典型的沉积型钙(镁)质磷块岩,前者选矿工艺复杂、选矿成本高、回收率低,后者已连续生产12年.为了更好地开发利用a层矿,本研究对a、b混合矿进行了选矿小实验和工业试验.工业试验结果表明:利用现有的一次反浮选选矿工艺和药剂制度进行(a b)混合选矿是可行的,而且药剂用量比单独选别b层矿时的药剂耗量少,回收率高,混合精矿达部标优质Ⅱ类产品要求.     

瓮福磷矿浮选加药系统的改造

在选矿厂中,对小流量、腐蚀性的工艺介质进行检测和控制是实现选矿厂工业自动化的一个难题.瓮福磷矿选矿厂浮选工艺加硫酸和加WF-01原设计通过控制电磁阀的每分钟的开启次数和每次的时间间隔来控制添加量,但由于加药不平稳和元件故障频繁,工艺指标无法控制,全部改为手动测量和调节.     

瓮福磷矿反浮选泡沫消泡研究

瓮福年处理250万吨磷矿选厂采用反浮选工艺,排出的泡沫产品相当稳定,给尾矿浆的输送及筑坝带来不利影响。为此,我们经过多种消泡剂及消泡方法试验,筛选出京泰110消泡剂,并通过扩大试验获得较好的消泡效果。 一、试验内容及结果 1、泡沫的物理化学特性 显微镜观测浮选泡沫小,泡壁厚(1.31×10~(-4)毫米),有较多的固体颗粒,属持久性泡沫。每升瓮福磷矿尾矿浆中,平均泡沫体积98.2毫升;湿重26.15克,干重7.7克,含水70.5％;尾矿干重110克,泡沫干重占尾矿总重的6.91％。     

浮选磷精矿用D50旋流器分级的试验研究

利用实验室D50mm旋流器对贵州某磷矿的浮选精矿进行了分级，在试验中对设备的参数和操作条件进行了优选，获得了一部分高质量的粗粒级磷精矿，满足了磷精矿出口创汇的要求。     

大峪口浮选磷精矿絮凝剂筛选试验

浓密机跑浑是造成精矿损失和过滤困难的重要原因。大峪口磷矿经多次试验筛选出絮凝剂FeSO4，经工业性试验效果良好，从根本上解决了浓密机压耙现象．生产流程畅通，并产生较好的经济效益。     

瓮福磷矿a层矿正反浮选工艺研究

以贵州瓮福磷矿a层矿为研究对象,借助XRD、显微镜等对原矿性质进行分析,在此基础上开展了矿石磨矿矿浆质量分数和磨矿细度试验,确定合适的磨矿矿浆质量分数为75％、磨矿细度为-0.075 mm质量分数占80％.利用单因素条件试验和正交试验确定:合适的正浮选捕收剂WF-03用量为1.8 kg/t,调整剂Na2CO3和抑制剂N...     

磷酸二铵造粒引风管堵塞的分析和解决

探讨磷酸二铵（DAP）生产过程中常见的故障原因分析及解决措施。     

Partial acidulation of an ‘unground’ phosphate rock: I. Preparation and characteristics

Partially acidulated phosphate rocks were prepared from unground North Carolina phsophate rock and H₃PO₄ by (i) mixing phosphate rock with the requisite amount of H₃PO₄, (ii) mixing with a portion of the acid followed by adding the remaining acid during granulation and (iii) single-step acidulation and granulation. The degrees of acidulation were 20, 30, 40 and 50%. Only 20% and 30% acidulations were done by method (iii). The phosphate rock granulated readily on addition of H₃PO₄ either as in method (ii) or (iii) and the products did not need external drying before storage. The citric and water soluble P showed that from the viewpoint of acid-phosphate rock interaction all three methods of preparation were satisfactory. The granules were equally strong as or stronger than commercially available single or triple superphosphate samples tested. The percent degradation on abrasion was less than 4% compared to about 8% for superphosphate and 0.4% for triple superphosphate. A sand incubation study suggested an interaction in the partially acidulated phosphate rock between the monocalcium phosphate component and unreacted phosphate rock which initially increased the solubility of P.     

The effects of nitrogen fertilizer form on the plant availability of phosphate from soil,phosphate rock and mono-calcium phosphate

A glasshouse trial using lettuce as the test crop, and laboratory incubations were used to evaluate the influence of various nitrogen fertilizers on the availability of phosphate from an unfertilized loamy sand soil and from the same soil fertilized with Sechura phosphate rock or monocalcium phosphate. The order in which nitrogen fertilizer form increased plant yield and P uptake from soil alone and from soil fertilized with the rock was ammonium sulphate > sulphurised urea > ammonium nitrate > urea > potassium nitrate. For each rock application (both 30 and 60 mg/pot) and for soil alone, increased P uptake by the plant correlated well with decreased soil pH. In soil fertilized with the soluble P form, monocalcium phosphate, the form of the nitrogen fertilizer had little effect on plant P uptake. Subsequent laboratory incubation studies showed that increased dissolution of soil-P or Sechura phosphate rock did not occur until acidity, generated by nitrification or sulphur oxidation of the fertilizer materials, had lowered soil pH to below 5.5. A sequential phosphate fractionation procedure was used to show that in soils treated with the acidifying nitrogen fertilizers, ammonium sulphate and urea, there was considerable release of Sechura phosphate rock P to the soil, amounting to 42% and 27% of the original rock P added, respectively.     

Synthesis,spray granulation and plasma spray coating of lanthanum phosphate nanorods for thermal insulation coatings

Nanorods of lanthanum phosphate obtained by a wet chemical precipitation route were granulated to obtain sizes in the range of 10–15 µm by spray drying from aqueous slurry of 35 wt% solid loading and 2 wt% of PVA binder. The powders thus obtained displayed enhanced flowability and were plasma sprayed on to stainless steel substrates resulting in the formation of adherent coatings of 150–180 µm thickness. These coatings were characterized using electron microscopy, X-ray diffraction analysis and Raman spectroscopy. X-ray analysis indicated phase instability of LaPO₄ during plasma spraying resulting in the formation of oxy and polyphosphates of lanthanum (La₂P₄O₁₃ and La₃PO₇). However, post deposition heat treatment of coated samples at 1100 °C for 2 h resulted in the reversible formation of stoichiometric lanthanum orthophosphate (LaPO₄). Raman spectral analysis was used to confirm the phase structure of the coatings deposited at various plasma input powers. The coatings obtained were found to effectively lower the thermal conductivity of the substrates from ~24 W/mK to less than 19 W/mK (~10%) even at 200 °C.     

流化床喷雾制备磷酸二氢钙成粒条件的实验研究

在底部直径为200 mm的锥形流化床中,研究了喷雾造粒制备粒状磷酸二氢钙的成粒条件,实验考察了喷淋密度、床层温度及流化气速等因素对成粒过程的影响,分析了磷酸二氢钙颗粒层式生长与团聚生长的机理,并给出了两种生长成粒的操作条件。     

Coupling granule properties and granulation rates in high-shear granulation

It is possible to link granulation rates to granule properties. The linkage is by multiple dimension population balance equations that, by means of simplifying assumptions, can be reduced to multiple one-dimensional (1-D) population balance equations (PBEs). Using simple physically based models, this paper demonstrates how multiple one-dimensional population balance equations can describe the results of high-shear granulation experiments of two different materials, calcium carbonate and lactose. Good agreement between experimental and simulated results was achieved enabling the granulation rates to be defined by two model parameters: the critical binder volume fraction and the aggregation rate constant. The modelling framework presented in this paper also provides a basis for the kinetic analysis of granulation experiments so that with further work, it is possible to determine the effect of process conditions and material properties on the model parameters.     

Foam granulation: Binder dispersion and nucleation in mixer-granulators

Traditional wet granulation method involves spraying of liquid binder onto a moving powder bed to granulate the powder particles in the granulator. A new alternative method of wet granulation has been developed where foam delivery of binder is used to granulate the powder particles.This study investigated binder distribution in wet granulation and focused on the nucleation stage, where nuclei are formed during the initial binder distribution. Nucleation experiments were used to study the formation of nuclei by the foam and spray delivery methods in a high shear mixer-granulator. The distribution of foams on a dynamic powder bed were also investigated by filming small portion of foams as they penetrated into moving powder beds under different powder flow conditions in a high shear mixer-granulator.Nucleation experiments in this study show that foam delivery tends to create a narrower nuclei size distribution during the early stage of wet granulation process compared to spray delivery at the same processing conditions, demonstrating the potential of foam granulation in achieving improved binder distribution. For foam delivery, the nuclei formation is influenced by the foam properties and powder flow conditions in the granulator. The experiments show that the narrowest nuclei size distribution is obtained by granulating with high-quality foam and intensive powder mixing conditions. Coarser nuclei are formed when low-quality foam is dispersed in a less intensively agitated powder. The interactions of foam quality and the powder flow pattern are discussed and two distinct wetting and nucleation mechanisms are proposed: (1) under bumping flow, a low-quality foam tends to induce localised wetting and nucleation. The wetting and nucleation is “foam drainage” controlled. (2) Under roping flow, foam will be dispersed by the motion of the agitated powder. The wetting and nucleation is “mechanical dispersion” controlled.     

NPK复混肥智能化粉体配料造粒装置及工艺流程

介绍智能化挤压造粒新技术在 NPK复混肥工艺中的应用。探讨如何解决干法挤压造粒在 NPK复混肥生产中出现的新问题     

氮化钒粉末造粒用胶粘剂的选择

氮化钒是VT包芯线粉芯材料的一种,经过破碎后细粉很多。为了改善粉末的流动性、提高细粉的利用率,提出了分级→造粒→干燥的工艺。该工艺流程的核心是造粒,而造粒工艺的关键是选择合适的胶粘剂。通过干球成粒率、干球落下强度、干球压缩强度、干球搅拌强度和干球外观形貌的对比,证明了淀粉胶粘剂的粘合效果优于石蜡粉,说明以低温淀粉胶粘剂为造粒用胶粘剂是合适的。     

5万t／a熔融尿素喷浆造粒装置若干问题的思考

介绍5万t/a熔融尿素喷浆造粒装置的工艺,阐述固体尿素熔融过程中缩二脲的控制、干燥系统设计以及装置设计的一些注意事项.