陶瓷多管除尘器在治理复合肥尾气粉尘中的应用

我公司复混(合)肥生产线是一条多功能肥料生产线,硫基复合肥、尿基复合肥、氮磷肥、磷钾肥、磷酸二铵、重钙都是在同一条生产线生产。由于不同品种肥料尾气性质不同(如硫基和尿基复合肥粉尘吸湿性强,氮磷肥粉尘颗粒细(绝大多数粒径在10μm左右),磷钾肥和重钙尾气腐蚀性大(气体含氟)),对粉尘治理设备的要求也不同。我们一直在寻求好的干法除尘方法来缓解湿式     

基于大型尿基复合肥装置的技术改造实践

分析了采用尿素料浆法工艺技术的30万t/a尿基复合肥装置生产中存在的问题;从控制重钙氨化程度、改变造粒调节剂、增加废水回用、改进原料输送方式、增加气氨管线等方面论述了尿基复合肥装置的技术改造措施;对比了技改前后生产应用数据,总结了技术改造效果。     

近期畅销的化工产品

化肥 液氨,尿素,碳铵,硫铵,氯化铵,硝铵,磷铵,普钙,重钙,硝酸磷肥,硫酸钾,氯化钾,复合肥,钾氮肥     

普钙改为重钙途径的探讨

由于普钙含有效磷低,不能适应农业发展的需要,贵州省化工局化工情报中心站对改造普钙品种提出了看法。认为普钙改为重钙(或富钙),采用离心机过滤流程,直接生产45～47%P_2O_5的磷酸,用浓酸法生产重钙,投资最省,普钙的设备可以全部利用;成本基本上接近普钙,且属高效磷肥;可以节约产品运输费用60%。     

尿基复合肥转产硝基复合肥应注意的事项

尿基复合肥和硝基复合肥相互转产是复合肥生产中的重要一环,其相互转产过程类似,但尿基复合肥转产硝基复合肥难度更大。从转产准备、停车清理、开车准备和投产生产等方面阐述了尿基复合肥转产硝基复合肥时应注意的事项。     

熔融尿液联产复合肥的生产工艺

介绍熔融尿液联产复合肥的生产技术:利用氯化钾溶于尿液中可形成低熔化合物,采用喷浆圆盘造粒、无干燥工艺流程,生产各种规格高浓度尿基复合肥,该工艺生产尿基复合肥不用干燥产品水分可达标,大大降低了投资和生产成本,技术与经济优势明显。     

重过磷酸钙生产技术分析及对今后工作的建议

一、重过磷酸钙生产技术特点 重过磷酸钙是用磷酸分解天然磷矿粉所制得的高浓度水溶性磷肥。它的外观与普通过磷酸钙(简称普钙)相似。但其有效P_2O_5含量达45％—50％,比普钙高2.5—3倍,所以称重过磷酸钙(简称重钙)。重钙与普钙在生产技术上有相当大的不同,重钙的技术发展与湿法磷酸的发展有密切关系,其工厂规模一般较大,过程也更趋于连续化。     

乌石化高浓度尿基复合肥装置的工艺特点

对比国内几家大型尿基复合肥装置,重点分析INCRO尿基复合肥生产工艺的特点,通过对乌鲁木齐石化总厂尿基复合肥生产工艺流程的设计介绍,首次提出以16大系统划分尿基复合肥装置工艺流程的理念,同时提出大型尿基复合肥装置需改进处和技改措施。     

全自动尿基／硝基一塔两用复合肥生产技术

在已有尿基高塔熔体造粒复合肥生产装置中进行技术创新与升级,在生产过程中既可生产尿基复合肥,又可生产硝基复合肥,能够根据需要实现2种复合肥氮源的自动切换,即一塔两用的高塔熔体复合肥造粒技术。该技术无需干燥过程,与原同等规模的料浆法生产装置相比,年可节约标煤9000t、节电3．4×10^6kW·h,综合节能30％。     

发展湿法重钙的建议

重过磷酸钙(简称重钙)是一种重要的高浓度速效磷肥,有效磷含量高达40～50%P_3O_5,相当于普通过磷酸钙(简称普钙)的2.5～3倍。对幅员辽阔、需长途运输的我国来说,发展重钙比普钙更为经济。同时,重钙对     

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.     

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。     

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--尿素系复肥生产技术简论

国内重过磷酸钙、尿素供应可靠，充分利用这两种原料生产高浓度复合肥，不仅生产成本较低，且能缓解国内重过磷酸钙和尿素的销售压力。就重过磷酸钙一尿素系复肥小型生产装置，介绍了其工艺流程和主要控制参数，并提出了提高产品水溶性的措施。     

A discussion of the methods for comparing the relative effectiveness of phosphate fertilizers varying in solubility

Because various phosphate (P) fertilizers differ widely in their solubility, it is commonly observed that crop response to P fertilizers varies under the same soil and crop conditions. Furthermore, a major problem encountered in the methods for determining the relative effectiveness (RE) of water-insoluble P fertilizer (e.g., phosphate rock) with respect to water-soluble P fertilizers, e.g., single superphosphate (SSP) and triple superphosphate (TSP), is that their growth response curves are usually nonlinear and often do not share a common maximum yield. In this paper, we review and discuss the advantages and disadvantages of the three most commonly used methods for calculating the RE of phosphate rock with respect to TSP (or SSP). The three methods are vertical comparison, horizontal (substitution rate) comparison, and linear-response comparison.     

Factors affecting the agronomic effectiveness of phosphate rock for direct application

Phosphorus (P) is critically needed to improve soil fertility for sustainable crop production in large areas of developing countries. In recent years, phosphate rock (PR) for direct application has been tested in tropical acid soils as a potential alternative to conventional water-soluble P fertilizers like single superphosphate (SSP) and triple superphosphate (TSP). Some developing countries have PR deposits which, if used to supplement other imported P fertilizers, would allow a saving of much needed foreign exchange. Solubility of P fertilizers is not the only criterion in selection of the most suitable P fertilizer. This paper discusses the results of experiments to compare the relative agronomic effectiveness (RAE) of various PR sources with respect to SSP or TSP as influenced by four important factors: PR sources, soil properties, management practices, and crop species. Under certain conditions, PRs can be agronomically effective.     

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.     

Efficient fertilizer use for increased crop production: The humid Nigeria experience

Fertilizer use in Nigeria, though growing, is still very low especially if considered in relation to the growing food needs of the country. Efforts have been made through scientific investigations to find ways of increasing fertilizer use efficiency in the humid zone of the country. Investigations have been carried out mainly on nitrogen, phosphorus, potassium, mixed and compound fertilizers. The secondary nutrients sulphur, calcium and magnesium as well as the micronutrients have received comparatively little attention. In the Southeastern humid zone, a considerable effort has been made to solve the problem of soil acidity through liming. Interaction of the primary nutrients under field conditions has not been investigated sufficiently.Results of experiments carried out on comparisons of P sources, urea placement methods and interaction of N, P, K, S fertilizers in the Ultisols of Southeastern Nigeria show that single superphosphate was superior to Togo phosphate rock, partially acidulated Togo phosphate rock, and diammonium phosphate for the production of maize. Methods of application of urea did not significantly affect maize grain yield. There was no significant interaction of N, P, K, S in the Ultisol but S was limiting. An application of a minimum of 45 kg/N/ha appears to be threshold for positive response to P by maize stover. More effort is needed to understand nutrient interaction in the Ultisols which are dominant in the humid Southern zone of Nigeria.     

Effectiveness of different phosphatic fertilizers measured using labelled superphosphate and phosphorus taken up by plants

The agronomic effectiveness of three P fertilizers (diamonium phosphate, rock phosphate and compost) was studied in a greenhouse experiment using wheat. A radioisotopic method, using triple superphosphate labelled with³²P, was used to evaluate the P in dried tops that was derived from i) the soil, ii) labelled superphosphate and iii) the fertilizer being studied.The ratio between P uptake from each fertilizer and P uptake from the soil was used to compare the effectiveness of the different fertilizers. P derived from diammonium phosphate was greater than P derived from the soil, except in one soil. P derived from rock phosphate was always lower than P derived from the soil. The effectiveness of compost depended on soil type. Compost can produce two kind of effects: i) a direct P contribution and ii) an indirect effect improving P uptake from the soil. The radioisotopic method can be used to study the effectiveness of fertilizers even when there are no differences in yield.     

利用部分过磷酸钙为磷源喷涂和氨化造粒法生产多品种硫基复合肥的工艺研究

介绍以过磷酸钙或重钙为部分或全部磷源,生产多品种,低、中、高浓度硫基复合肥的工艺原理,流程,设备选型,工艺指标,技术要点。该工艺已在很多工厂实施,运行效果很好。