富过磷酸钙料浆固化条件的实验室研究

采用二水物湿法稀磷酸与硫酸的混酸分解四川清平磷矿制取富过磷酸钙，研究了影响料浆固化的因素。结果指出，原料硫酸与磷酸的配比、混酸中氢离子浓度和含水量是影响富过磷酸钙固化的主要条件。得出用四川清平磷矿制取固化良好的富过磷酸钙的适宜条件范围     

用四川清平磷矿制富过磷酸钙的中试

用四川清平磷矿制富过磷酸钙的中试涂敏端，费德君，曹尚崇，魏贵方（四川联合大学化工系）（四川省绵竹磷肥厂）１前言富过磷酸钙（简称富钙）系用混酸（硫酸和磷酸）分解磷矿制成。产品的主要成分是磷酸一钙Ｃａ（Ｈ＿２ＰＯ＿４）＿２·Ｈ＿２Ｏ和硫酸钙，还含少量游离...     

磷矿性质与重过磷酸钙生产的关系

本文从磷矿在磷酸中的反应动力学和重过磷酸钙物料物系的溶解度性质出发,讨论了重过磷酸钙生产对磷矿质量和性质的要求。鉴于我国不少磷矿的反应活性偏低和(或)杂质特别是镁含量较高,对重钙生产产生不利的影响。本文对我国重过磷酸钙生产建设中原料磷矿的选择和工艺选择提出了原则建议。     

硫磷混酸分解磷矿反应动力学研究

采用四川清平磷矿和金河磷矿、贵州福泉和开阳磷矿为原料，试验研究了用硫磷混酸分解磷矿制取富过磷酸钙的反应动力学，分析了影响反应速度的主要因素，导出了用硫磷混酸分解磷矿的动力学方程式及判别过程的控制步骤。     

富过磷酸钙制造技术的研究

研究了分别用热法磷酸、湿法磷酸与硫酸组成的混酸，分解其磷矿制造富过磷酸钙时混酸用量，混酸浓度、磷酸代替量、陈化时间等工艺条件及其影响，对富过磷酸钙的制造工艺技术有一定的参考价值。     

尿素过磷酸钙的新工艺研究

通过一系列的实验室试验和小型中间连续试验，明确了宜昌磷矿制尿素过磷酸钙的可行性。通过与先前实验的比较，可以认为在制尿素过磷酸钙时，宜昌磷矿的反应活性介于摩洛歌磷酸与开阳磷矿之间。通常，较低的熟化温度对尿素过磷酸钼产品的品质有利，研究表明，尿素过酸酸钙新工艺较“固化无机酸工艺更适合我国国是值得应用。     

关于过磷酸钙成品结块问题的探讨

关于过磷酸钙成品结块问题的探讨张在灿，何俊（武穴市化工总厂）用宜昌磷矿生产过磷酸钙，由于该磷矿硬度大、难分解，大都采用于法生产。但成品出厂后几乎都存在结块现象。我厂采用宜昌磷矿生产过磷酸钙，针对成品存在的结块现象，１９９３年进行了探索，有效地控制了磷...     

过磷酸钙生产中磷矿的搭配

介绍磷矿的杂质对过磷酸钙生产的影响，并总结出不同磷矿的搭配方法。根据云浮市磷肥厂的生产实践，说明不同性质的磷矿搭配使用的可行性和重要性。     

结合四川磷矿特点发展磷肥工业

本文讨论了四川金河、清平磷矿在品位、品质、比表面及微晶结构上的特点，指出：结合因矿制肥政策，四川什邡磷矿系应针对现有产品普通过磷酸钙进行改造，改善磷矿的反应活性，以提高产品的有效养分，提高产品质量。     

磷酸中杂质镁对重过磷酸钙生产的影响

研究磷酸中不同含量的杂质镁对磷酸物性、磷矿酸解反应过程及重过磷酸钙产品质量的影响，结果表明：加入杂质镁后，不仅磷酸的粘度、密度和中和度有较大变化，而且影响重过磷酸钙产品的质量和磷矿的分解率。     

国外富过磷酸钙生产技术动态

本文介绍了国外富过磷酸钙生产技术的新进展。讨论了富过酸钙在我国的发展前景。     

Long-term residual value of North Carolina and Queensland rock phosphates compared with triple superphosphate

The effectiveness of large single applications of North Carolina reactive rock phosphate, Queensland non-reactive rock phosphate, and Calciphos, were compared to the effectiveness of superphosphate in field experiments in south-western Australia for up to 11 years after application. As measured using plant yield, superphosphate was the most effective fertilizer in the year of application, and relative to freshly-applied superphosphate, the effectiveness of the superphosphate residues declined to be about 15 to 65% as effective in the year after application, and 5 to 20% as effective 9 to 10 years after application. Relative to freshly-applied superphosphate, all the rock phosphates were 10 to 30% as effective in the year of application, and the residues remained 2 to 20% as effective in the 10 years after application. The bicarbonate soil test reagent predicted a more gradual decrease in effectiveness of superphosphate of up to 70% 10 years after application. For rock phosphate, the reagent predicted effectiveness to be always lower than for superphosphate, being initially 2 to 11% as effective in the year after application, and from 10% to equally as effective 10 years later. Therefore rock phosphates are unlikely to be economic alternatives to superphosphate in the short or long term on most lateritic soils in south-western Australia.     

仿真探讨磷矿组分对过磷酸钙生产的影响规律

过磷酸钙是我国传统的磷肥品种之一,采用工艺计算方法,仿真探讨了磷矿中主要组分氟磷酸钙、碳酸钙(镁)、三氧化铁(铝)和氟化钙对过磷酸钙生产指标的影响规律,结果表明:氟磷酸钙质量分数增大,过磷酸钙产品的质量指标(有效P2O5、游离磷酸P2O5、游离水等的质量分数)随之增大,产率和硫酸消耗定额也随之增大,磷矿消耗定额随之降低...     

The effect of direct application of phosphate rock on increasing crop yield and improving properties of red soil

Field experiments, designed to evaluate the effect of direct application of phosphate rock, were carried out on red soil (Ultisol) uplands at three different places. The results indicated: (1) for the first year's crop, the rapeseed yields with phosphate rock treatment and triple superphosphate treatment were almost identical when their rate of phosphorus application was the same; (2) when the same level of phosphorus fertilizer was applied, the residual effect of phosphate rock was better than that of triple superphosphate, and the residual effect of all phosphorus fertilizers on winter crop yields increased with the increase of the amount of Phosphorus applied; (3) with the application of phosphate rock, the pH value, the amount of available phosphorus and exchangeable Ca and Mg of soils went up, whereas the content of active Al in soils decreased. Therefore, the direct application of phosphate rock to red soil also has an important role in improving soil properties.The project was financially supported by American Phosphate Foundation, PPI/PPIC and National Natural Science Foundation of China.     

Effectiveness of partially acidulated phosphate rock as a source to plants in calcareous soils

In a series of greenhouse experiments granulated phosphate fertilizers prepared by mixing triple superphosphate with phosphate rock and partially acidulated phosphate rock, ranging in their content of water souble P from 95 to 17 per cent of total P were applied to neutral and slightly alkaline (pH 6.9–7.8), sandy loam to clay soils ranging in calcium carbonate content from 2 to 35 percent. Dry matter yield of clover, alfalfa, millet or maize were obtained, P uptake determined and sodium bicarbonate extractable P in soil measured. In one field experiment triple superphosphate was compared to mixture of triple superphosphate and phosphate rock on maize. X ray difraction on one triple superphosphate — phosphate rock mixture and on one partially acidulated phosphate rock showed that both fertilizers contain mainly monocalcium phosphate and fluorapatite. After incubation in soil the dicalcium phosphate content rose and the monocalcium phosphate disappeared.Parameters received in greenhouse experiments and in the field indicate that phosphate fertilizers composed of superphosphate and up to 50 percent phosphate rock are as efficient source of P to plants on calcareous and slightly alkaline soils as superphosphate. If this indication would be proven in extensive field experimentation it would lead to savings in acid consumption and in fertilizer manufacturing plant capacity for calcareous soils.     

The residual value of superphosphate and rock phosphates for lateritic soils and its evaluation using three soil phosphate tests

The residual value of superphosphate and several rock phosphates was measured in three field experiments in Western Australia. The rock phosphates were Christmas Island C-grade ore, calcined C-grade ore (Calciphos) and apatite rock phosphates. The predictive capacity of the Colwell, Olsen and Bray 1 soil tests for phosphate were also evaluated.As measured by yields of variously wheat, oats, barley or clover, the effectiveness of an initial application of superphosphate decreased to about 50% of that of newly applied superphosphate between years 1 and 2, and further decreased to about 20% over subsequent years. At low levels of application, all the rock phosphates were between 10–20% as effective as superphosphate in the year of application for all experiments. Relative to newly applied superphosphate their effectiveness remained approximately constant in subsequent years for two experiments and doubled for the other experiment.The Colwell soil test predicted that the effectiveness of superphosphate decreased to about 45% between years 2 and 3, followed by a more gradual decrease to approximately 15%. At low levels of application, the effectiveness of the rock phosphates as predicted by the Colwell soil test values was initially very low relative to superphosphate (2–30%), and remained low in subsequent years (2–20%). For superphosphate treated soil, the proportion of the added phosphorus extracted generally increased as the level of application increased. By contrast, for rock phosphate treated soil, the proportion of added phosphorus extracted decreased as the level of application increased.For all three experiments there were highly significant positive correlations between amounts of P extracted by the three soil tests. Consequently all soil tests were equally predictive of yield but usually for each soil test separate calibrations between yield and soil test values were required for the different fertilizers and for each combination of fertilizer and plant species and for each year.     

Effectiveness of Ecophos compared with single and coastal superphosphates

Ecophos is a possible alternative phosphorus (P) fertilizer to single and coastal superphosphate for clover pasture (Trifolium subterraneum) on P leaching, sandy, humic podzols in the > 800 mm annual average rainfall areas of south-western Australia. Ecophos and coastal superphosphate are partially acidulated rock phosphates (PARP) fertilizers. Ecophos is made from calcium iron aluminium (crandallite millisite) rock phosphate. Coastal superphosphate is made from apatite. The sandy humic podzols are known to promote extensive dissolution of rock phosphates, including the untreated rock phosphate present in PARP fertilizers. In this field study (early April 1992 to end of October 1994), the effectiveness of the PARP fertilizers was calculated relative to the effectiveness of single superphosphate (relative effectiveness or RE), using yield and P content of dry clover herbage. The RE of the PARP fertilizers varied markedly between assessments, both within and between years, from being much less effective than single superphosphate, to equally or much more efective. This great diversity in RE is attributed to the different extents P can be leached in the soil, depending on seasonal conditions. It is concluded that Ecophos is a suitable alternative P fertilizer for the soil and environment studied.     

Evaluation of two rock phosphates and a calcined rock phosphate as maintenance fertilizers for crop — pasture rotations in Western Australia

Two long-term (11 and 12 y) field experiments in south-western Australia are described that measured the relative effectiveness of three rock phosphate fertilizers (C-grade ore, Calciphos and Queensland (Duchess) rock phosphate), single, double and triple superphosphate. The experiments were on established subterranean clover (Trifolium subterraneum) — based pasture that had received large, yearly, applications of single superphosphate for many years before the experiments began so that in the first year the nil phosphorus (P) treatment produced 80 to 90% of the maximum yield. The experiments were conducted using a rotation of one year cereal crop (oats,Avena sativa at one site, and barley,Hordeum vulgare, at the other): 2 y pasture, a typical rotation on farms in the region. Five levels of each P fertilizer were applied every third year with the crop. Grain yield of cereals, P content of grain, pasture yield, and bicarbonate-soluble P extracted from the soil (available P) were used to estimate fertilizer effectiveness values.The three superphosphate fertilizers had identical values of fertilizer effectiveness. Superphosphate was always the most effective fertilizer for producing grain. The rock phosphate fertilizers were one-seventh to one-half as effective per kg P as superphosphate when assessed on the yield or P content (P concentration × yield) of grain within each cropping year. Bicarbonate-extractable soil P values demonstrated that superphosphate was two to fifteen times as effective as the rock phosphate fertilizers. The relationship between grain yield and P content in grain (i.e. the internal efficiency of P use curve) was similar for the different P fertilizers. Thus for all P fertilizers yield was not limited by other factors as it varied solely in response to the P content, which in turn presumably depended on the P supply from the fertilizers.The relative agronomic effectiveness of rock phosphates is greater for marginally P deficient soils than for highly P deficient soils but rock phosphate remains less effective than superphosphate. We conclude that the rock phosphates studied should not be substituted for superphosphate as maintenance fertilizers for soils in Western Australia that are marginally deficient in P. This result is consistent with the results of many field experiments on highly P deficient soils in south-western Australia. These have shown that a wide variety of rock phosphate fertilizers are much less effective than superphosphate in both the short and long term.     

重过磷酸钙产品的推广和应用

重过磷酸钙是由磷酸分解矿粉后得到的高浓度磷肥,是重要的磷肥品种。重过磷酸钙可直接施用,也可作为制造其它三元肥料的原料。本文全面回顾上海化工研究院在重钙的研制工作中所取得的成果,并对今后有关重钙相关技术的开发提出了有益的设想和建议,以期推动重钙生产的进一步发展。     

The comparative agronomic effectiveness of rock phosphate and superphosphate for banana

The agronomic effectiveness of three rock phosphates (Idaho, Florida and North Carolina) as influenced by mycorrhizal inoculation withGlomus aggregatum was evaluated using small banana (Musa paradisiaca L.) corms as planting material. The treatments included superphosphate and a no-P control. The soil was fumigated to eliminate mycorrhizal propagules. The amount of P added was based on the quantity of material needed as superphosphate to establish 0.2 mg P L^–1 in solution. Plants were grown in an Oxisol in 9-liter pots for 3 months after growth commenced. Plant dry weight, P percentage in the 3rd leaf, and total P uptake were increased when plants fertilized with insoluble rock phosphates were inoculated with mycorrhiza-producing fungi. Phosphorus uptake by plants fertilized with Idaho, Florida, and North Carolina rock phosphates was 0.18, 0.42, and 0.97 as much as by plants fertilized with superphosphate. The beneficial effect of mycorrhiza on phosphate uptake was 136, 30, 2 and 24% for plants fertilized with Idaho, Florida and North Carolina rock phosphate, and superphosphate, respectively.