Production of dicalcium phosphate by treatment of phosphate rock concentrate with nitric acid

This paper presents results laboratory experiments to test a new process for manufacture of dicalcium phosphate. The process is based on the nitric acidulation of phosphate rock concentrate, followed by neutralization of the extract liquor with calcium carbonate. The precipitated dicalcium phosphate is then separated from calcium nitrate solution by filtration. The dicalcium phosphate thus obtained contains 44–47% total P₂O₅ and can be used as fertilizer or, with an additional low pH filtration step, as animal feed supplement.     

硝酸分解磷矿生产饲钙、硝酸磷肥、硝酸钠的工艺技术

开发用硝酸分解磷矿制备饲料磷酸氢钙、工业硝酸钠及硝酸磷肥工艺,高效利用中低品位磷矿资源的技术,可将贵州丰富的磷、煤资源及国内的芒硝资源优势转化为产业优势,减少磷化工对硫资源的过度依赖,提高磷矿资源利用率,避免了磷石膏的排放,促进企业清洁生产,发展循环经济,实现可持续发展。     

磷酸氢钙国际市场状况调查

本文针对国外牙膏用、食品用及医药用磷酸氢钙的生产及市场状况做一简单的介绍 ,并对我国磷酸氢钙的发展提出了建议。     

饲料级磷酸氢钙中钙含量不稳定因素的研究

通过实验,分析饲料级磷酸氢钙中钙含量不稳定的影响因素,磷矿粉m(MgO)/m(P2O5)、生石灰中MgO含量对磷酸氢钙中钙含量影响最大,二段中和pH值及产品结晶水的含量对磷酸氢钙中钙含量也有一定的影响。研究结果表明:饲钙产品w(Ca)要达20%以上,磷矿粉中m(MgO)/m(P2O5)应控制在11%以下,生石灰的w(MgO)最好控制在3%以下;同时,二段中和pH值控制在5.8～6.3与中和溶液温度控制在50℃以下,有利于产品的结晶水形成和获得粗大的产品结晶。     

In-situ and dump leaching technology: Application to phosphate rock

The technology of in-situ and dump leaching, used widely by hydrometallurgists, can be applied with advantage to the exploitation of phosphate rock deposits especially those low in limestone. Nitric or hydrochloric acids of certain concentrations would be used instead of H₂SO₄ and the solutions obtained treated to remove radium and recover uranium and the lanthanides if desired, then evaporated to crystallize the double salt CaXH₂PO₄H₂O, where X = Cl or NO₃; this can be decomposed at 200°–250°C to form dicalcium phosphate, CaHPO₄, a high grade marketable product. Nearly all the acid required for leaching can be regenerated and recycled.     

饲料级磷酸氢钙标准样品的研制

简述了饲料级磷酸氢钙标准样品的研制过程，并对样品作了稳定性试验，对搅拌设备的搅拌均匀性和物料的均匀性进行了测定，并由国家认可实验室进行了定值数据的监测。通过对比实验证明了国家实验室之间的无差异性。实验数据表明了所测定的饲料级磷酸氢钙产品是稳定和均匀的，同时简要介绍标准样品的研制程序，为开发其他化工行业标准样品奠定了基础。     

饲料级磷酸氢钙用矿探讨

利用二段中和法生产饲钙的生产数据分析发现,为达到m(P2O5)/m(F)≥220,不同磷矿所需控制的一段中和pH值有很大差异,对于易脱氟的磷矿控制pH较低(2.2~2.3)即可达到脱氟要求,而此时m(P2O5)/m(R2O3)值较小,即随铁、铝带走的磷损失少,可大大提高饲钙生产的技经指标,获得较好效益。因此,饲钙用矿,首先应考查其脱氟性能,这是决定饲钙生产经济效益的主要因素。并提出了磷矿特性对目的产品适用性的概念。     

矿粉脱氟法生产饲料级磷酸氢钙主要工艺指标控制

根据连云港新磷矿化有限责任公司所用磷矿的特点,探讨矿粉脱氟法生产饲料级磷酸氢钙工艺过程中脱氟、萃取、中和3个关键岗位工艺指标的控制.选择适合的工艺控制指标,取得了良好的效果,与传统二段中和法比,硫酸、石灰消耗明显减少,P205回收率提高15％～20％.     

酸热法脱氟磷酸钙的生产

阐述了酸热法脱氟饲料磷酸钙生产工艺流程短、焙烧温度低、生产成本低等优点，提出应该重视酸热法脱氟磷酸钙的生产。     

回收低浓度磷酸液中的磷生产饲料级磷酸氢钙

介绍采用两级反应法回收低浓度磷酸液中的磷生产饲料级磷酸氢钙的反应原理,考察了中和液p H、干燥条件对产品质量的影响。结果表明,控制中和液p H 5.8~6.0、干燥温度100℃以下、干燥时间1~2 h,所得产品符合GB/T 22549—2008标准,具有良好的经济效益。     

世界磷矿生产消费格局及其变化

介绍世界磷矿资源分布、生产消费格局及其变化。世界磷矿资源分布比较集中,其中以摩洛哥储量最多;世界磷矿石主要用于磷肥生产,其消费量呈增长趋势,其中美国磷矿石消费量下降、中国磷矿石消费量增长,磷矿石价格波动下降;世界磷酸盐产能、产量均增长,磷肥供应持续过剩,预测磷肥供应格局将向中东、北非地区转移。     

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.     

Agronomic evaluation of fertilizer products derived from Sukulu Hills phosphate rock

Partial acidulation of phosphate rock (PR) or compaction of PR with soluble P fertilizers can improve the usefulness of unreactive PR for use as P fertilizer. A greenhouse study was conducted to evaluate nonconventional phosphate fertilizers derived from a low reactive Sukulu Hills PR from Uganda. Raw PR (which contained 341.0 g kg^–1 Fe₂O₃), beneficiated or concentrate PR, partially acidulated PR (PAPR) and PR compacted with triple superphosphate (TSP) were evaluated. Compacted materials had a P ratio of PR:TSP = 50:50. PAPR materials were made by 50% acidulation with H₂SO₄. TSP was used as a reference fertilizer. Fertilizers were applied to an acidic (pH = 5.4) Hiwassee loam (clayey, kaolinitic, thermic Rhodic Kanhapludults) at rates of 0, 50, 100, 200, 300 and 400 mg P kg^–1 soil. Two successive corn (Zea mays L.) crops were grown for 6 weeks. Compacted concentrate PR + TSP and raw PR + TSP were 94.4 and 89.7% as effective as TSP, respectively, in increasing dry-matter yields for the first corn crop. PAPR from the concentrate was 54.8% as effective as TSP. Raw PR, concentrate PR and the PAPR from the raw PR were ineffective in increasing dry-matter yields. The same trends were obtained when P uptake was used to compare effectiveness. Ineffectiveness of the raw PR and its corresponding PAPR was attributed to a high Fe₂O₃ content in the raw PR. Bray I and Pi paper were found to be nearly equally suitable at estimating available P in the soils treated with responsive fertilizer materials. Mehlich 1 overestimated available P in soil treated with raw PR, concentrate PR or the PAPR from the raw PR.     

微波在快速测定饲料级磷酸氢钙中全磷的应用

采用微波作用使饲料级磷酸氢钙消解和生成沉淀一步完成,对实验参数进行了探索。结果表明,在酸性介质中,正磷酸根与钼酸铵微波作用生成黄色的磷钼酸铵沉淀,沉淀经过滤、洗涤,用碱标准溶液溶解,过量的碱溶液用酸标准溶液滴定,可掌握生产中全磷的变化趋势,实现边生产边监控边调整。     

氢化物发生原子吸收光谱法测定饲料级磷酸氢钙中微量铅

介绍一种饲料级磷酸氢钙中微量铅的测定方法。用盐酸溶液溶解后的试样,在HCl-K3Ye（CN）6-NaBH。反应体系中,采用氢化物发生原子吸收光谱法测定铅含量。本方法相关系数r=0．9987,加标平均回收率范围在98．45％～100．75％．     

Induced phosphorus fixation and the effectiveness of phosphate fertilizers derived from Sukulu Hills phosphate rock

A greenhouse study was conducted with two surface, acidic soils (a Hiwassee loam and a Marvyn loamy sand) to measure the effect of increasing P-fixation capacity, on the relative agronomic effectiveness (RAE) of phosphate fertilizers derived from Sukulu Hills phosphate rock (PR) from Uganda. Prior to fertilizer application, Fe-gel was added to increase P-fixation capacity from 4.4 to 14.3% for the Marvyn soil and from 37.0 to 61.5% for the Hiwassee soil. Phosphate materials included compacted Sukulu Hills concentrate PR + Triple superphosphate (CTSP) at a total P ratio of PR:TSP = 50:50; 50% partially acidulated PR (CPAPR) from Sukulu Hills concentrate PR made with H₂SO₄; and Sukulu Hills concentrate PR (PRC) made by magnetically removing iron oxide from raw PR ore. Triple superphosphate (TSP) was used as a reference fertilizer. After adjusting soil pH to approximately 6, P sources were applied at rates of 0, 50, 150, and 300 mg total P kg^–1 soil. Two successive crops of 5 week old corn seedlings (Zea mays L.) were grown. The results show that the RAE of the phosphate materials measured using dry-matter yield or P uptake generally decreased as P-fixation capacity was increased for both soils. CTSP was more effective in increasing dry-matter yield and P uptake than CPAPR. PRC alone was an ineffective P source. Soil chemical analysis showed that Bray 1 and Mehlich 1 extractants were ineffective on the high P-fixation capacity Fe-gel amended Hiwassee soil. Mehlich 1 was unsuitable for soils treated with PRC since it apparently solubilizes unreactive PR. When all of the soils and P sources were considered together, Pi paper was the most reliable test for estimating plant available P.     

用湖南浏阳磷矿生产过磷酸钙

阐述浏阳磷矿的缺点及其对过磷酸钙生产的影响。云浮市磷肥厂采用浏阳矿生产过磷酸钙 ,提高成品转化率的措施为 :将浏阳矿与开阳矿合理搭配使用 [m(浏阳矿 ) / m (开阳矿 )≤ 1],矿粉粒度 <0 .14 7mm的占 96 %以上 ,采用低温低浓工艺和控制较稀的混化料浆 ,并适当延长搅拌时间和熟化期。采取上述措施后 ,成品转化率达到87.3% ,拓宽了磷矿的来源     

用混合磷矿石生产优等品磷酸二铵的措施

甘肃瓮福公司采用云南、贵州、四川多个矿点磷矿石生产磷酸二铵(DAP),根据磷矿石杂质含量和杂质转化率,采取数据模型法确定科学的配矿比例,并加强配矿管理,合理地控制关键工艺指标,达到稳定生产,磷酸二铵优等品达95%以上。     

脱氟磷酸三钙生产技术新进展

简要评述脱氟磷酸三钙的性质,生产原理和世界生产及应用情况,重点介绍上海化工研究院"以煤粉为燃料的脱氟磷酸盐制造方法"的生产流程和特点.     

利用磷矿中氟资源生产冰晶石

提出应该利用磷肥生产副产氟硅酸（或氟硅酸钠）代替萤石生产冰晶石，并介绍其生产技术和在我国没有大规模工业化生产的原因及目前尚存在的问题。