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我国几种典型磷矿反应特性和发泡特性的研究 总被引:8,自引:0,他引:8
研究了我国浏阳磷矿、开阳磷矿、清平磷矿和金河磷矿的反应活性、抗阻缓性和发泡特性,并对发泡性严重的磷矿进行了消泡实验。 相似文献
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磷矿浮选尾矿矿石特性研究 总被引:2,自引:0,他引:2
以贵州瓮福磷矿浮选后的尾矿资源为研究对象,研究了其反应活性、抗阻缓性及酸解反应工艺特性.得出,尾矿主要物相是白云石,其反应活性为99.65%,抗阻缓系数为12.87,最佳酸解反应工艺条件为:反应时间90 min,液固比3,浸出温度80℃,酸过量系数1.05,MgO的浸出率高于P2O5的浸出率(均高于95%).研究表明:瓮福磷矿浮选尾矿反应活性好,有一定的抗阻缓性,MgO和P2O5在酸解过程中近乎是同时浸出,只是前者略高于后者.本研究可为综合利用浮选尾矿中的镁、磷提供必要的基础理论依据,对低品位磷矿的利用有一定借鉴作用. 相似文献
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以湿法磷酸基础理论研究分析以湖北为代表的中品位磷矿的化学和物相组成、反应活性、抗阻缓性和发泡特性及磷酸氨化中和。分析总结用此类磷矿采用传统法生产磷铵过程中主要工艺指标的操作范围。分析结果表明此类磷矿的酸解能力及抗阻缓性能力和国内其他中品位磷矿没有大的区别,由此提出此类磷矿传统法生产磷铵的工艺控制范围。 相似文献
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介绍评价磷矿反应活性的实验装置;用磷矿在一定浓度酸液中,在一定温度、一定反应时间下的分解率表示磷矿的反应活性。实验研究了不同因素对磷矿反应活性的影响,并测试了11种磷矿的反应活性指数及抗硫酸的阻缓性能。评价方法与实验结果均具有参考价值。 相似文献
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介绍了磷矿组成和分类,我国磷矿资源特点,国内外磷矿的生产与消费。阐述了磷矿的反应活性和抗阻缓性是评判磷矿加工性能的主要因素。根据《全国磷资源开发》项目评审会的评判纪录,结合相关的理化数据和实践经验,从78个代表性磷矿样中整理出磷肥和磷复肥生产用矿进行评价。指出“酸热并举、以酸法为主发展高浓度磷复肥”是合乎我国磷矿资源实际情况的。 相似文献
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昆阳磷矿作二次矿生产节酸磷铵的实验室研究 总被引:1,自引:1,他引:0
对采用云南昆阳磷矿作二次矿生产节酸磷铵的可行性进行了系统的实验研究,并与已经工业生产验证的贵州开阳矿的可应用性进行比较,得到前者比后者更优越的结论。 相似文献
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Reactive extrusion and solid acid catalysis technologies were adopted in the pentaerythritol–melamine phosphate (PER‐MP) reaction to synthesize intumescent flame retardant, melamine salt of pentaerythritol phosphate (MPP), which was applied in flame retardant polypropylene (PP). This environment‐friendly synthesis method provided a solution to the problems of conventional methods. On one hand, reactive extrusion in a twin screw extruder can effectively mix and transfer viscous materials that usually results in a tough stir in a conventional reactor, and achieve a continuous synthesis process. On the other hand, the solid acid, silicotungstic acid (STA) serving as a catalyst, can maintain a satisfactory conversion even with a low extrusion temperature and a short residence time, thus effectively suppressing foaming in the process of the reaction. Furthermore, without removal like other catalysts in general chemical reactions, STA was kept in produced MPP to constitute a synergism flame retardant system, therefore further improved the flame retardancy. LOI and UL94 test showed that the STA‐catalyzed MPP (by reactive extrusion) possessed much better flame retardancy in PP when compared with the noncatalyzed MPP (by reactive extrusion), as well as present commercial MPP (by POCl3 method). In our investigation, the catalytic and synergistic effects of STA, as well as the related factors of the reactive extrusion affecting the conversion of the PER‐MP reaction, flame retardancy and mechanical performance of the corresponding flame retardant PP, were systematically investigated. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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滇池地区中低品位胶磷矿重浮选矿试验研究 总被引:6,自引:0,他引:6
根据滇池地区晋宁、昆阳、海口中低品位胶磷矿的矿物特性,确定以重浮联合流程选别中低品位胶磷矿。结果表明:利用重选预选减少入浮选量一定程度上降低了选矿成本,减小了浮选对环境的污染。 相似文献
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以沙土盆栽试验研究了微细磷矿粉提高土壤速效磷含量及其生物有效性。结果表明:磷矿粉有效磷含量、水溶性磷含量及土壤速效磷和水溶性磷含量随颗粒细度提高而提高,特别是大部分颗粒细度在20μm以下时,有效磷和水溶性磷含量增幅较大,越是难溶的磷矿粉提高幅度越大。当磷矿粉粒度达到大部分在20μm以下时,与0.100~0.075mm粒度所含有效磷相比,绵竹和昆阳的磷矿粉分别提高6.97和6.09倍,怀化和晋宁的磷矿粉分别提高5.96和2.64倍,安宁和开阳的磷矿粉分别提高2.59和0.84倍;6个产地的磷矿粉的水溶性磷含量提高1.20~8.56倍;晋宁和开阳的磷矿粉对产量贡献率分别提高24%和10%左右,而且分别提高土壤速效磷含量130%和53%。 相似文献
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以窑法工艺对云南晋宁低品位磷矿的碳热还原性能进行研究。采用4因素5水平正交实验探究反应温度、反应时间、碳过量系数、硅钙物质的量比对磷矿碳热反应还原率的影响。实验结果表明,影响磷矿还原率由大到小的顺序依次为,反应温度、碳过量系数、反应时间、硅钙物质的量比。反应温度为1 300 ℃、碳过量系数 为2.6、反应时间为1.5 h、硅钙物质的量比为1.5时,还原率可达到最高值94.27%。同时,对云南晋宁低品位混合型磷矿用于窑法磷酸生产的适应性进行评价,表明该混合型磷矿适用于窑法磷酸生产,研究结果对低品位混合型磷矿窑法工艺具有一定指导意义。 相似文献
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为改进湿法磷酸生产工艺,提高副产石膏的品质,缓解湿法磷酸中固体副产物磷石膏带来的环保压力,进行了磷-硫两步法酸解磷矿制磷酸的研究。着重对贵阳某磷矿在磷酸中的浸出行为进行研究。结果表明,磷矿粒度小于75 μm、搅拌速度为500 r/min、反应温度为70 ℃、五氧化二磷质量分数为40%、反应时间为60 min时,磷矿分解率达到98.5%。德罗兹多夫动力学经验模型能够较好地描述40%五氧化二磷中磷矿反应速率的变化规律,且阻缓系数较大,表观活化能为6.048 kJ/mol,表明40%五氧化二磷中磷酸分解磷矿的反应速率受扩散控制。酸解渣SEM和EDS分析表明反应产物磷酸二氢钙结晶析出是影响扩散的主要因素。 相似文献
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The role of mixtures of reactive bromine and phosphorus flame-retardant polyol intermediates as well as the individual bromine and phosphorus reagents in suppressing combustion of flexible polyurethane foams was investigated by means of the oxygen index flame test and charring techniques. Bromine alone appears to contribute to flame retardancy in the solid as well as the vapor phase. A substantial portion of the bromine from both aliphatic and aromatic bromide flame retardants was accounted for in the char, and this is also true when phosphorus is present. Ionic bromine appears to be the most effective elemental form. Like phosphorus, bromine alone in foams is also observed to increase the yield of char. Aliphatic bromide in mixture with phosphonate or phosphate gave enhanced flame retardancy, whereas, mixtures with phosphite are not beneficial. Maximum flame retardancy and char yields correlate well for bromine mixed with phosphate and phosphonate, whereas the relationship does not hold with phosphites. Charring experiments at 500°C with foams containing both phosphorus and bromine generally afforded a constant P/Br ratio, suggesting a specific chemical interaction for flame retardancy. Phosphate flame-retardant efficiency was sensitive to concentration of phosphorus in the foams. On the other hand, phosphonate and phosphite exhibited a constant level of fire resistance at phosphorus levels greater than 0.3%. 相似文献
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贵州织金磷精矿湿法磷酸工艺的探索 总被引:1,自引:0,他引:1
针对贵州织金地区磷矿石特点,用二水物湿法磷酸工艺对其浮选精矿进行萃取。通过考察温度、液固比、酸过量系数、时间等因数对P2O5转化率的影响,确定最佳工艺参数。实验结果表明:在反应温度75±3℃,酸过量系数1.03,液固比2.5∶1,反应时间3 h条件下,磷的转化率可达到97.75%。 相似文献