φ4.75m×18.5m带内反料装置喷浆造粒干燥机的工艺设计

介绍４．７５ ｍ ×１８．５ ｍ 带内返料装置喷浆造粒干燥机的工艺设计、主要技术参数,并与不同干燥机的使用情况进行对比,生产表明：设计满足了１０万吨／年硫基ＮＰＫ复合肥的干燥要求,干燥设备尚具有一定的增产潜力。     

复混肥转鼓造粒机的改造

介绍巴陵分公司100 k t/a复混肥装置2台转鼓造粒机,内衬改为氯丁橡胶后,如何解决了粘壁问题。安装挡圈滑轨调节挡圈位置后,可灵活改变造粒区与抛光区的长度,从而使造粒机能适应高、中、低浓度复肥的生产,使造粒机生产能力提高20%,清理时间从2~3 h减为0.5 h,成球率从65%提高到85%,产品外观改善、质量提高。     

尿素熔融喷浆造粒工艺生产高氮复混肥

介绍在团粒法工艺的基础上,用尿素熔融成尿液或尿素车间二段蒸发器的尿液,采用喷浆造粒工艺生产w(N)25%~28%高氮复合肥的工艺要点:控制尿素用量占40%以下,尿液w[(NH2)2CO]≥99%;控制造粒w(H2O)≤2.5%;要求造粒物料温度≥60℃。改进干燥机内部结构,控制大风量低温干燥条件,4年的生产表明:工艺状况稳定,产品产量质量提高,消耗降低。     

公路拓宽地基强夯振动传播规律研究

利用FLAC 3D数值计算软件,建立了强夯振动的有限差分模型,分析了路侧地基强夯振动在公路路基、路面中的传播规律。以关键测点的振动加速度与锤底土动压力值作为分析指标,分析了夯锤落距(锤重)、夯锤直径对路基、地基的振动和地基加固效果的影响规律。通过公路拓宽室内模型试验,验证了数值分析的可靠性。结果表明,在1 500 k N·m夯击能下,采用6 m的夯锤落距(对应夯锤锤重为25 t)、1.5 m或2.0 m夯锤直径可以获得理想地基加固效果,且对周边环境振动影响最小;路基坡脚处强夯振动加速度较平面地形衰减更为显著;路面结构中振动加速度总体呈现快速衰减趋势,内侧加速度最大值为3.9 m/s2,路面基层、底基层内的强夯振动加速度基本一致,均小于面层的振动加速度。     

两步氨化法生产硫基复合肥技术

介绍两步氨化法生产硫基复合肥的原理和流程.及对传统硫基复合肥工艺的若干改进.该工艺在硫酸氢钾溶液中通入气氨并添加一种可改变物料结晶性状及输送性能的物质,从而可大大降低物料水分,达到高效、节能、提高产品质量的目的;并且采用部分固体物料从返料中加入,有利于养分调节,可生产高氮、高磷及通用型产品,产品外观质量好,水分低,不易结块.     

原位反应包膜控释复合肥的养分释放

利用静态水中溶出实验和模拟土壤环境的淋溶实验,研究了含生物质油的包膜原料经原位反应制得包膜复合肥的养分释放.用电导率法和吸光度法分别对离子型养分K+、H2PO4-和NH4+和总氮素的释放进行了研究.结果表明,以生物质油为基本原料,在复合肥表面原位反应包膜可以制得符合欧洲标准委员会规定的控释肥;养分的释放速率与包膜材料组成和膜的化学结构等因素有关.     

复合肥生产的粉尘治理与回收

针对复合肥生产粉尘大、操作环境差、尾气不能达标排放的问题,进行了粉尘治理和回收的技术改造,介绍改造的工艺流程及主要设备.改造后不仅改善了环境,尾气实现达标排放,而且原料收率明显提高,年回收成本达262.5万元.     

我国复合肥行业的现状和未来发展

介绍了我国复合肥行业现状:产业规模快速发展,实现自给自足;产能过剩,产业集中度低,市场亟待完善;资源瓶颈削弱了产业竞争力;农化服务体系建设滞后,制约市场发展.指出在国家政策的支持和引导下,复合肥仍是未来的发展方向.复合肥行业应注重降低成本、科技创新,提升产品的复合化率、专用化率.产业整合是大势所趋,大型央企在整合中将扮演重要角色.     

我国复合肥行业面临的挑战

分析我国复合肥行业与市场面临的原材料上涨、成本增加、市场开放、出口开征关税、取消优惠政策等不利因素的挑战,提出应加快企业间并购步伐;接受市场整合,降低经营风险;产品创新的同时大力进行营销创新;坚决打击仿冒伪劣复合肥等应对挑战的措施.     

复合肥营销原理初探

从产品组合、定价、销售渠道3个方面对如何将市场营销原理应用于复合肥销售中进行了阐述.并指出:基于销售额和利润的最大化、基于市场保护、基于农民的施肥习惯是复合肥营销策略中品种策划工作的基本原则;产品组合要通过应用成本导向定价法和目标定价法对复合肥定价策略进行指导;通过有效的营销渠道建设既能够整合复合肥企业现有资源,又可以实现安全畅通的销售模式,对复合肥企业应对新形势下的市场竞争至关重要.     

Drying process optimization for an API solvate using heat transfer model of an agitated filter dryer

Drying an early stage active pharmaceutical ingredient candidate required excessively long cycle times in a pilot plant agitated filter dryer. The key to faster drying is to ensure sufficient heat transfer and minimize mass transfer limitations. Designing the right mixing protocol is of utmost importance to achieve efficient heat transfer. To this order, a composite model was developed for the removal of bound solvent that incorporates models for heat transfer and desolvation kinetics. The proposed heat transfer model differs from previously reported models in two respects: it accounts for the effects of a gas gap between the vessel wall and solids on the overall heat transfer coefficient, and headspace pressure on the mean free path length of the inert gas and thereby on the heat transfer between the vessel wall and the first layer of solids. A computational methodology was developed incorporating the effects of mixing and headspace pressure to simulate the drying profile using a modified model framework within the Dynochem software. A dryer operational protocol was designed based on the desolvation kinetics, thermal stability studies of wet and dry cake, and the understanding gained through model simulations, resulting in a multifold reduction in drying time.     

Correlation of laboratory and production freeze drying cycles

The purpose of this study was to develop the correlation of cycle parameters between a laboratory and a production freeze-dryer. With the established correlation, key cycle parameters obtained using a laboratory dryer may be converted to those for a production dryer with minimal experimental efforts. In order to develop the correlation, it was important to consider the contributions from the following freeze-drying components: (1) the dryer, (2) the vial, and (3) the formulation. The critical parameters for the dryer are the shelf heat transfer coefficient and shelf surface radiation emissivity. The critical parameters for the vial are the vial bottom heat transfer coefficients (the contact parameter Kcs and separation distance lv), and vial top heat transfer coefficient. The critical parameter of the formulation is the dry layer mass transfer coefficient. The above heat and mass transfer coefficients were determined by freeze-drying experiments in conjunction with mathematical modeling. With the obtained heat and mass transfer coefficients, the maximum product temperature, Tbmax, during primary drying was simulated using a primary drying subroutine as a function of the shelf temperature and chamber pressure. The required shelf temperature and chamber pressure, in order to perform a successful cycle run without product collapse, were then simulated based on the resulting values of Tbmax. The established correlation approach was demonstrated by the primary drying of the model formulation 5% mannitol solution. The cycle runs were performed using a LyoStar dryer as the laboratory dryer and a BOC Edwards dryer as the production dryer. The determined normalized dried layer mass transfer resistance for 5% mannitol is expressed as RpN=0.7313+17.19l, where l is the receding dry layer thickness. After demonstrating the correlation approach using the model formulation 5% mannitol, a practical comparison study was performed for the actual product, the lactate dehydrogenase (LDH) formulation. The determined normalized dried layer mass transfer resistance for the LDH formulation is expressed as RpN=4.344+10.85l. The operational templates Tbmax and primary drying time were also generated by simulation. The cycle run for the LDH formulation using the Edwards production dryer verified that the cycle developed in a laboratory freeze-dryer was transferable at the production scale.     

In vitro evaluation and intra-articular administration of biodegradable microspheres containing naproxen sodium

The camu-camu, like many other Amazonian fruits, shows an excellent potential for use due to its high vitamin C content, and the use of these natural resources could result in greater development of the Amazonian region. Few studies have been conducted with this fruit, and such studies are necessary in order to develop the required technology to allow for its utilization, thus avoiding or at least decreasing wastage of such a rich raw material. The principle objective of this study was to develop a process for the microencapsulation of camu-camu juice, optimizing the operational conditions. The processing conditions consisted of blanching at a temperature of 95 ± 2;°C for 2 min, followed by cooling in an ice bath and juice extraction using a brush type depulper. The juice was dried with gum arabic or malt dextrin in a mini-spray dryer using an air entry temperature of between 100-160°C and wall material concentration varying between 5-35%, in accordance with a factorial experimental design. Both the air entry temperature and the amount of wall material, plus the interaction between the two, gave significant positive effects at the level of 5% probability on the yield of juice powder. The optimum conditions for juice yield and vitamin C retention were established as 15% wall material and an air entry temperature of 150°C.     

Benefit of microwaves in case of heat-sensitive agglomerate drying

The microwave assisted vacuum drying of heat-sensitive materials is increasing in the pharmaceutical industry since the eighties. This paper deals with results of two experiment series obtained on a laboratory scale single pot dryer (Collette Ultima 251). Firstly water was heated up to the boiling point exclusively by predetermined microwave energy and then by various wall temperatures in order to determine the convection efficiency of the system. The experiments were carried out at fixed pressure level (80 mbar) and with optimum bowl load (15 kg). According to the demonstrated idea each single pot system efficiency can be specified at any type and quantity of load. With the help of the presented results the second experiments were designed to compare the microwave and convection efficiency of the single pot system during granule drying. A placebo granule was dried either by an exclusive convection or microwave method up to the determined LOD (< 0.5%). According to the tests extreme high wall temperature (85 degrees C) had to be used to achieve the same drying time--and efficiency--as with the usage of dielectric heating. Based on the results it can be stated that the shorter drying time under favourable conditions is the advantage of microwave radiation over the conventional technique.     

Preclinical pharmacokinetics and interspecies scaling of a novel vitronectin receptor antagonist.

Allometric scaling may be used in drug development to predict the pharmacokinetics of xenobiotics in humans from animal data. Although allometry may be successful for compounds that are excreted unchanged or that are oxidatively metabolized (with corrections for metabolic capacity), it has been more challenging for compounds excreted primarily as conjugates in bile. (S)-10, 11-Dihydro-3-[3-(pyridin-2-ylamino)-1-propyloxy]-5H-dibenzo[ a, d]cycloheptene-10-acetic acid (SB-265123) is a novel alphavbeta3 ("vitronectin receptor") antagonist. In this study, the in vivo pharmacokinetics and in vitro plasma protein binding of SB-265123 were examined in four species: mice, rats, dogs, and monkeys. In monkeys and dogs, SB-265123 exhibited moderate clearance, whereas low clearance (<20% hepatic blood flow) was observed in the rat, and high clearance (>70% hepatic blood flow) was seen in the mouse. The concentration-time profiles indicated the possibility of enterohepatic recirculation; subsequent studies in bile duct-cannulated rats demonstrated extensive biliary excretion of an acyl-glucuronide of SB-265123. In allometric scaling to predict the disposition of SB-265123 in humans, various standard correction factors were applied, including protein binding, maximum lifespan potential, and brain weight; each failed to produce adequate interspecies scaling of clearance (r(2) < 0.72). Consequently, a novel correction factor incorporating bile flow and microsomal UDP-glucuronosyltransferase activity in each species was applied, demonstrating substantial improvement in the correlation of the allometric plot (r(2) = 0.96). This study demonstrates a novel allometric correction that may be applicable to compounds that undergo conjugation and biliary excretion.     

Quantitative real-time monitoring of dryer effluent using fiber optic near-infrared spectroscopy

This paper describes a method for real-time quantitation of the solvents evaporating from a dryer. The vapor stream in the vacuum line of a dryer was monitored in real time using a fiber optic-coupled acousto-optic tunable filter near-infrared (AOTF-NIR) spectrometer. A balance was placed in the dryer, and mass readings were recorded for every scan of the AOTF-NIR. A partial least-squares (PLS) calibration was subsequently built based on change in mass over change in time for solvents typically used in a chemical manufacturing plant. Controlling software for the AOTF-NIR was developed. The software collects spectra, builds the PLS calibration model, and continuously fits subsequently collected spectra to the calibration, allowing the operator to follow the mass loss of solvent from the dryer. The results indicate that solvent loss can be monitored and quantitated in real time using NIR for the optimization of drying times. These time-based mass loss values have also been used to calculate "dynamic" vapor density values for the solvents. The values calculated are in agreement with values determined from the ideal gas law and could prove valuable as tools to measure temperature or pressure indirectly.     

Cashew gum microencapsulation protects the aroma of coffee extracts

Microencapsulation of materials rich in volatile compounds by spray drying presents the challenge of removing water by vapourization without loss of odour and/or flavour components. Crioconcentrated coffee extracts rich in odour components were used as a substrate core to evaluate microencapsulation with cashew gum from Anacardium occidentale L. In Brazil, cashew gum is a low cost alternative to the traditional Arabic gum. A suspension containing coffee extract and the wall material was dissolved in water and then passed through a spray dryer. Core microcapsules were microwave-assisted extracted (MAE) and the aroma protection of the microcapsules produced was evaluated using gas chromatography and mass spectroscopy (GC/MS). The external morphology and size distribution of the microcapsules were obtained by scanning electron microscopy (SEM) and light scattering techniques, respectively. When comparing Arabic and cashew gum microencapsulation of coffee extracts both wall materials were observed to have similar aroma protection, external morphology and size distribution. Sensory analysis was employed to examine flavour protection and consumer preference with microencapsulation. These biochemical, sensory and structural data suggest that low cost cashew gum is a well suited alternative for odour microencapsulation to the more costly Arabic gum currently used in Brazil.     

Model-based approaches for ivabradine development in paediatric population,part I: study preparation assessment

The main objective was to help design a paediatric study for ivabradine, a compound already marketed in adults, focusing on: the paediatric formulation evaluation, the doses to be administered, the sampling design and the sampling technique. A secondary objective was to perform a comparison of the prediction of ivabradine pharmacokinetics (PK) in children using a physiologically-based pharmacokinetic (PBPK) approach and allometric scaling of a population pharmacokinetic (PPK) model. A study was conducted in order to assess the relative bioavailability (Frel) of the paediatric formulation and a similar Frel was observed between the paediatric formulation and the adult marketed tablet. PBPK modelling was used to predict initial doses to be administered in the paediatric study and to select the most appropriate sample time collections. The dried blood spot technique was recommended in the clinical trial in children. Simulations obtained by both the PBPK approach and allometric scaling of a PPK model were compared a posteriori to the paediatric study observations. Both PPK and PBPK approaches allowed an adequate prediction of the PK of ivabradine and its metabolite in children.     

SFD—SMTD二级干燥装置用于悬浮聚氯乙烯和双嘧达莫中间体干燥的中试

旋转闪蒸干燥器（ＳＦＤ）和旋流中等滞时干燥器（ＳＭＴＤ）组成二级干燥装置,ＳＦＤ快速除去物料中的表面水分,而ＳＭＴＤ进一步除去结合水分,能提高热效率和生产能力。进行了该二级干燥器用于悬浮聚氯乙烯（ＰＶＣ）树脂和双嘧达莫中间体“四羟物”干燥的中试。ＳＦＤ与ＳＭＴＤ的直径分别为３００和４００ｍｍ,Ｓ－ＰＶＣ滤饼含湿量约２５％,双嘧达莫中间体“四羟物”约６２％。经干燥得到含湿量分别≤０．３％和≤０．５％     

A comprehensive quantitative and qualitative evaluation of extrapolation of intravenous pharmacokinetic parameters from rat, dog, and monkey to humans. I. Clearance.

This study was conducted to comprehensively survey the available literature on intravenous pharmacokinetic parameters in the rat, dog, monkey, and human, and to compare common methods for extrapolation of clearance, to identify the most appropriate species to use in pharmacokinetic lead optimization, and to ascertain whether adequate prospective measures of predictive success are currently available. One hundred three nonpeptide xenobiotics were identified with intravenous pharmacokinetic data in rat, dog, monkey, and human; both body weight- and hepatic blood flow-based methods were used for scaling of clearance. Allometric scaling approaches, particularly those using data from only two of the preclinical species, were less successful at predicting human clearance than methods based on clearance as a set fraction of liver blood flow from an individual species. Furthermore, commonly used prospective measures of allometric scaling success, including correlation coefficient and allometric exponent, failed to discriminate between successful and failed allometric predictions. In all instances, the monkey tended to provide the most qualitatively and quantitatively accurate predictions of human clearance and also afforded the least biased predictions compared with other species. Additionally, the availability of data from both common nonrodent species (dog and monkey) did not ensure enhanced predictive quality compared with having only monkey data. The observations in this investigation have major implications for pharmacokinetic lead optimization and for prediction of human clearance from in vivo preclinical data and support the continued use of nonhuman primates in preclinical pharmacokinetics.