化肥信息

化肥信息料浆法磷铵中和浓缩一体化新工艺料浆法磷铵中和浓缩一体化新工艺是由成都科技大学开发，与山东莱西市磷肥厂合作完成的３万吨级工业考核实验。该工艺是将“湿法磷酸氨中和”与“中和料浆蒸发浓缩”二个过程合并在一台蒸发器中完成，从而省去了现有料浆法磷铵装置...     

中和磷铵料浆无泵浓缩流程

中和磷铵料浆无泵浓缩流程漆平，汪朝生，周道勇（四川德阳市化工厂）１前言在３０ｋｔ／ａ磷铵料浆法浓缩装置上，国内通用设计均采用双效逆流蒸发流程，即中和后的料浆首先流入料浆缓冲槽，经加料泵送入Ⅱ效蒸发器内，料浆在Ⅱ效蒸发器内初步浓缩后，经过料泵送入Ⅰ效蒸...     

国内最简单的“料浆法”磷铵生产装置

国内最简单的“料浆法”磷铵生产装置应建康，蒋绍志，王佐才，蓝荣森（四川联合大学化工系）（四川省金河磷矿）“磷铵料浆中和浓缩一体化”新技术是近年来继“喷浆造粒内返料”技术之后，国内在“料浆浓缩法”磷铵生产工艺领域中所取得的一项最新的、较大的技术进步。该...     

论料浆法磷铵工艺的技术经济优势（续）

论料浆法磷铵工艺的技术经济优势（续）应建康钟本和张允湘（四川联合大学６１００６５）５物能消耗当采用相同质量磷矿作原料时，料浆法磷铵工艺的物料消耗，存在一定优势。在湿法磷酸部分已如前述，料浆法工艺在适当降低磷酸浓度指标后，由于洗涤率提高和机械损失减少，...     

复混肥生产技术综述

综述了复混肥料的生产技术和特点，介绍了团粒法，料浆法，熔体法以及挤压法生产颗粒复混肥的工艺流程。     

15万吨／年料浆法磷铵流程的方案比较

１５万吨／年料浆法磷铵流程的方案比较刘代俊，钟本和，张允湘（四川联合大学化工系）自“七五”以来，应用“料浆浓缩法”生产磷铵的流程，我国已建立了７０套３万吨／年规模的装置，两套６万吨／年规模的装置。磷铵料浆法流程的生产、管理、研究和设计已积累了丰富的经...     

节硫型料浆法磷铵新工艺通过鉴定

节硫型料浆法磷铵新工艺通过鉴定由四川联合大学和四川省南川市维丰化工总公司联合承担的国家“九五”重点攻关课题《节硫型料浆法磷铵新工艺》，于１９９６年６月２７日通过由化工部主持的专家技术鉴定。新工艺将传统的重过磷酸钙生产方法与“料浆法”磷铵生产工艺结合在...     

腐植酸钠在磷铵生产中固氮作用的研究

中和料浆浓缩法磷铵工艺生产过程中,随着磷铵料浆中和度上升,浓缩和干燥工序的氨逸出急剧增加,使料浆法工艺生产磷酸二铵十分困难。本文研究了中和料浆中加入腐植酸钠提高磷铵料浆固氮性能,从而减少磷酸二铵加工过程的氨损失。通过实验得出腐植酸钠的最佳加入量为中和料浆中P2O5含量的2%。     

磷铵装置料浆加热器严重结垢原因分析

针对料浆法磷铵装置料浆加热器严重结垢的问题,从低压蒸汽温度、原料磷酸指标、料浆指标、中和浓缩生产方式和料浆过滤器等方面进行分析,认为变更中和浓缩生产方式、延长料浆滞留时间是造成料浆加热器严重结垢的主要原因。     

粉状磷酸一铵中和浓缩工段工艺初步设计

本文主要介绍了粉状磷酸一铵（MAP）生产工艺，对SAI流程、Minifos流程、SAC流程等传统磷酸浓缩法工艺和中和料浆浓缩法磷铵新工艺做了简述对比，着重阐述了中和料浆浓缩法磷铵新工艺的发展、特点及前景。     

重钙装置改产磷铵后氨化造粒机内部构件的配置研究

重钙装置改产磷铵后,造粒机内的物料行为发生了变化,即“料浆涂布－水分蒸发－氨化反应”这一物理化学过程。喷氨孔与水平线的夹角是影响这一过程的重要因素,本文对夹角的确定进行了理论分析。在实验基础上,对造粒机预中和料浆喷头位置、氨分布管的长度和角度进行了重新配置。生产表明,重新配置的造粒机内部构件具有很好的造粒效果。     

Map manufacture using the pipe reactor

Texasgulf, at its Lee Creek, NC facility, has converted its Dorrco GTSP plant to alternate production of MAP, 11-52-0, or 11-55-0. The use of a TVA 10 inch Pipe Reactor has resulted in high ammoniation efficiencies, low emissions of fluorine and ammonia and completely satisfactory products. The Pipe Reactor, currently not used widely for MAP at capacities above 50 TPH, has advantages in being able to use high strength acid, resulting in low recycle and high capacity, with emissions well below Florida and EPA Standards.At Texasgulf, relative low strength acid (38% to 43% P₂O₅) is used. In this case, virtually all the available reaction heat is released into the granulator to raise the granulator temperature and maximize moisture elimination.The paper discusses the current state-of-the-art in Pipe Reactor processing, particularly in North America, compares alternate processes for MAP and discusses the operation of DAP using the Pipe.     

40万t／a重钙装置反应,造粒系统技改方案

简要评述我厂重钙装置反应、造粒系统工艺条件对操作的影响,提出影响反应、造粒工段操作的４条改进措施。     

Effect of recoating slurry compositions on the microstructure and properties of SiC reticulated porous ceramics

Silicon carbide reticulated porous ceramics (SiC RPCs) were fabricated by polymer sponge replica technique, followed by recoating with SiC slurries of two different sintering additives of MgO–Al₂O₃–SiO₂ (Slurry 1) and polycarbosilane (Slurry 2). The sintering temperature of SiC RPCs recoated with Slurry 2 was 1100 °C, which was 200 °C lower than that for one recoated with Slurry 1. The prepared SiC RPCs exhibited homogeneous microstructure and contained pores with different sizes which was entrapped in the strut of SiC RPCs, small pores with diameter lower than 4 μm and large pores with diameter higher than 10 μm. Bending strength of SiC RPCs recoated with Slurry 1 was two times higher than that for the non-recoated samples, which was 1.88 MPa and was a little higher than that for one recoated with slurry 2. At the same time, high thermal shock resistance and high refractoriness were achieved for SiC RPCs recoated with Slurry 2.     

Charakterisierung von Slurry‐ Fermentationsprozessen als Grundlage für die mathematische Modellierung

Characterization of the Slurry Fermentation for Modeling The criteria for the characterization of the classical fermentation processes: Submerged, Emerged and Solid‐State Fermentations do not sufficiently describe all processes in those systems. Slurry Fermentation is an independent fermentation system that covers or encompasses processes that do not correspond to the classical systems and therefore require theoretical characterization. Slurry is understood as a two‐phase, monodisperse system with a continuous liquid phase, characterized by a high suspension viscosity and a limited convective mass transfer. Three cases are distinguishable: (1) lower volume fraction, high suspension viscosity and diffusive mass transfer (2) high volume fraction, high suspension viscosity, and diffusive mass transfer and (3) high volume fraction, high suspension viscosity and micro‐convective mass transfer.     

重油催化油浆过滤技术概述

重油催化油浆具有重要的开发应用价值,但大量的残留催化剂颗粒限制了其作为高附加值产品的应用。催化剂颗粒的去除技术具有很强的实用性和经济价值。本文综述了近几年重油催化油浆过滤技术的发展概况,并列举了一些应用实例。     

Lipids in the germ,endosperm and pericarp of the developing maize kernel

Acyl lipids were quantified in the germ, endosperm and pericarp of LG-11 maize kernels at eight stages of development from 9 to 87 days after pollination (DAP). Changes in the lipids are discussed in relation to morphological events in the developing kernel. Storage lipids (triglyceride, steryl ester) and membrane lipids (diacylphospholipids) accumulated in germ until 52-76 DAP, then decreased slightly without formation of lipid degradation products, lated in endosperm until 36-42 DAP and then decreased. Maximum values for galactosyldiglycerides and diacylphospholipids (nonstarch lipids) were reached at 16-23 DAP, and all decreased to very low values at maturity. Loss of these functional (membrane) lipids during the period of endosperm cell filling is unexpected. Starch contained 82% of the lysophospholipids and 64% of the free fatty acids in endosperm at 76 DAP. Endosperm lysophospholipids increased until 76 DAP and then decreased slightly, while free fatty acids increased continuously mostly inside starch granules at all stages of development, and any possible decrease after 76 DAP was masked by acids formed by hydrolysis of aleurone and endosperm nonstarch lipids from 52 DAP. In DAP, and phospholipids decreased after 42 DAP. Loss of these lipids is associated with senescence of most pericarp tissue. Triglycerides and steryl esters accumulated steadily to maturity, while the main accumulation of unsaponifiables occurred after 52 DAP about the time of suberin formation.     

Nitrogen-15 and sulfur-35 balances for fertilizers applied to transplanted rainfed lowland rice

A field experiment was conducted on a poorly-drained Aeric Paleaquult in northeastern Thailand to determine the effect of N and S fertilizers on yield of rainfed lowland rice (Oryza sativa L.) and to determine the fate of applied¹⁵N- and³⁵S-labeled fertilizers. Rice yield and N uptake increased with applied N but not with applied S in either sulfate or elemental S (ES) form. Rice yield was statistically greater for deep placement of urea as urea supergranules (USG) than for all other N fertilizer treatments that included prilled urea (PU), urea amended with a urease inhibitor (phenyl phosphorodiamidate), and ammonium phosphate sulfate (16% N, 8.6% P).The applied¹⁵N-labeled urea (37 kg N ha^–1) not recovered in the soil/plant system at crop maturity was 85% for basal incorporation, 53% for broadcast at 12 days after transplanting (DT), 27% for broadcast at 5–7 days before panicle initiation (DBPI), and 49% for broadcast at panicle initiation (PI). The basal incorporated S (30 kg ha^–1) not recovered in the soil/plant system at crop maturity was 37% for sulfate applied as single superphosphate (SSP) and 34% for ES applied as granulated triple superphosphate fortified with S (S/GTSP). Some basal incorporated¹⁵N and³⁵S and some broadcast¹⁵N at PI was lost by runoff. Heavy rainfall at 3–4 days after basal N incorporation and at 1 day after PI resulted in water flow from rice fields at higher elevation and total inundation of the 0.15-m-high¹⁵N and³⁵S microplot borders. Unrecovered¹⁵N was only 14% for 75 kg urea-N ha^–1 deep placed as USG at transplanting. This low N loss from USG indicated that leaching was not a major N loss mechanism and that deep placement was relatively effective in preventing runoff loss.In order to assess the susceptibility of fertilizer-S to runoff loss, a subsequent field experiment was conducted to monitor³⁵S activity in floodwater for 42 days after basal incorporation of SSP and S/GTSP. Maximum³⁵S recoveries in the floodwater were 19% for SSP after 7 days and 7% for S/GTSP after 1 day. Recovery of³⁵S in floodwater after 14 days was 12% for SSP and 3% for S/GTSP.This research suggests that on poorly drained soils with a low sorption capacity, a sizeable fraction of the fertilizer S and N remains in the floodwater following application. Runoff could then be an important mechanism of nutrient loss in areas with high probability for inundation following intense rainfall.     

Isotopic discrimination associated with symbiotic nitrogen fixation in stylo (Stylosanthes hamata L.) and cowpea (Vigna unguiculata L.)

A glasshouse study was carried out to determine the isotopicdiscrimination (B values) and the isotopic fractionation factors ()associated with symbiotic nitrogen fixation in stylo (Stylosantheshamata L.) and cowpea (Vigna unguiculata L.Walp). The B values are required to improve the accuracy of estimates ofnitrogen fixation based on the differences in the natural abundance of¹⁵N between nitrogen fixing and non-fixing plants. The B values ofplants grown in nitrogen free media for stylo were –1.60, 82 days after planting (DAP) and –1.86, 98 DAP and –1.48, 49DAP and –1.51 for cowpea shoots 73 DAP. Theisotopic fractionation factors for stylo and cowpea were 1.0016, 82DAP and 1.0019, 98 DAP and 1.0018, 49 DAPand 1.0015, 73 DAP, respectively.