一种降低过磷酸钙水分的方法

介绍一项新的研究成果，在过磷酸钙生产中加入一种添加剂，可以控制过磷酸钙含水量达到１４％，而且每吨过磷酸钙成本只增加２～３元，并可提高过磷酸钙一个品级，具有显著的经济效益。     

油页岩微波干燥过程分析及模拟

以柳树河油页岩为原料,分别在100℃热风温度和不同的微波功率的干燥条件下进行试验;用Weibull分布函数对油页岩的干燥曲线进行拟合分析,结合尺度参数估算水分有效扩散系数。结果表明:加速干燥阶段脱除的是油页岩颗粒的表面水;前期存在预热过程,温度升高,水分析出很少;随后干燥速率显著增大。恒速阶段析出的也是表面水,受物理脱附作用的影响;功率越大,恒速段时间越短。降速第一阶段主要是大孔隙中水分的脱除,降速第二阶段主要是中孔和微孔中水分的汽化。临界水分比随功率的增加而升高。Weibull分布函数准确模拟了油页岩微波干燥曲线;尺度参数α值随功率增加而减小,功率大于550 W后减小幅度降低;微波干燥的形状参数β1,即升速段出现在干燥前期;估算的水分有效扩散系数随功率增加而增大。微波干燥和热风干燥时相比,油页岩颗粒形态并没有发生显著变化。     

湿法过磷酸钙水分达标的工艺技术

我公司磷肥厂于１９８７年建成投产,最初采用干法生产,由于原料工段粉尘污染严重,维修费用高等原因,于１９９１年改造为浓酸矿浆法生产过磷酸钙,改造后产品水分经常超标。为了确保产品质量,近几年在工艺指标控制及设备改造方面采取了一系列措施,达到了预期的效果,...     

过磷酸钙造粒,干燥与熟化时间关系的探讨

通过过磷酸钙造粒、干燥，以加快过磷酸钙的熟化速度，缩短熟化期，提高过磷酸钙的生产能力。     

微波及辐射真空干燥过程中的干燥动力学及能量消耗

The general objective of this work is to analyze energy input in a vacuum process with the incorporation of microwave heating. Thus, necessary criteria for designing an efficient freeze-drying operation are considered through the analysis of strategies based on the combination of different intensities of raxiiant and microwave heating.The other aim of this research topic is to study the kinetics of drying in relation to mass transfer parameters.Five freeze-drying strategies using both heating systems were used. Consequently, energy input could be related to diffusivity coefficients, temperature and pressure profiles during dehydration of the product and analyzed in comparison to a conventional freeze-drying process.     

微波加热测定硫磺中的水分

<正> 硫磺中水分的测定,历来采用控温加热挥发失重的方法。国标GB2452-81规定在80℃控温烘箱中加热3小时,称量至恒重而后计算烘去的水分。国际标准ISO3426-1975和英国标准B.S4113-1967也作了相似的规定,前者将温度定在80℃,后者则定在105℃。在控温加热过程中,基体硫磺和被测组分水分同时被加热。     

湿法过磷酸钙生产中产品水分的达标

湿法过磷酸钙生产中产品水分的达标徐为温（福建省沙县化肥厂８６５５００）自矿浆浓酸法生产过磷酸钙的方法问世以来，众多厂家就被成品水分超标的问题所困扰。水分超标不仅是内在质量问题，还使产品的物理性能变坏，水分一旦超过１５％．产品会发粘、结块。即使装包前经...     

微波干燥在日用陶瓷工业生产中的应用

介绍了微波干燥在日用陶瓷工业生产的应用条件和使用特点,实现对产品的快速脱水干燥的过程,微波是一种频率极高的电磁波。     

Accurate Determination of Moisture Content of Organic Soils Using the Oven Drying Method

Abstract

The accuracy of moisture content values determined for organic soil using the oven drying method is dependent on the oven drying temperature. Some charring of the organic fraction occurs at the standard oven drying temperature of 110 ± 5°C; pore water remains in the soil when temperatures below 100°C are used. A new technique to determine the specific oven drying temperature that yields the correct value of the moisture content for organic soils is presented. Routine moisture content tests should be conducted at the standard oven drying temperature; moisture content values determined on the basis of the recommended oven drying temperature of 60°C include a larger error. A moisture content parameter is introduced to facilitate direct comparison of moisture content values calculated on the basis of different oven drying temperatures.     

Accurate Determination of Moisture Content of Organic Soils Using the Oven Drying Method

The accuracy of moisture content values determined for organic soil using the oven drying method is dependent on the oven drying temperature. Some charring of the organic fraction occurs at the standard oven drying temperature of 110 ± 5°C; pore water remains in the soil when temperatures below 100°C are used. A new technique to determine the specific oven drying temperature that yields the correct value of the moisture content for organic soils is presented. Routine moisture content tests should be conducted at the standard oven drying temperature; moisture content values determined on the basis of the recommended oven drying temperature of 60°C include a larger error. A moisture content parameter is introduced to facilitate direct comparison of moisture content values calculated on the basis of different oven drying temperatures.     

微波加热测定盐酸小檗碱的水分

用微波加热测定盐酸小檗碱中的水分。研究表明,将微波炉调于ＭＥＤＬＯＷ档,加热时间控制４５ｍｉｎ,所测定盐酸小檗碱中水分的结果与药典法测定的结果一致。     

气相色谱法测定过磷酸钙中三氯乙醛

过磷酸钙中的三氯乙醛用异丙醇提取,采用气相色谱法、微电子捕获检测器(ECD)进行测定。该方法具有快速、简单、灵敏度高等优点,适合过磷酸钙中三氯乙醛的测定。     

Analysis of Moisture Content and Density of Pears During Drying

Abstract

Solar dried pears of the “S. Bartolomeu” variety are a very much appreciated and preferred dried food product in Portugal. Nevertheless, the traditional solar drying is carried out at open air during the months of 07 and 08, and this nowadays is a disadvantage for larger productions. This work is to evaluate the possibility of producing dried pears from this and other varieties, maintaining the characteristics of the traditional dried pears. In this study four different types of pears were studied, including “S. Bartolomeu” as a basis for comparison and the drying method employed was the traditional one. From the results it was concluded that, although the behaviour of the four varieties do not vary significantly, one particular variety (“D. Joaquina”) is a good alternative to the “S. Bartolomeu” pear.     

Analysis of Moisture Content and Density of Pears During Drying

Solar dried pears of the “S. Bartolomeu” variety are a very much appreciated and preferred dried food product in Portugal. Nevertheless, the traditional solar drying is carried out at open air during the months of 07 and 08, and this nowadays is a disadvantage for larger productions. This work is to evaluate the possibility of producing dried pears from this and other varieties, maintaining the characteristics of the traditional dried pears. In this study four different types of pears were studied, including “S. Bartolomeu” as a basis for comparison and the drying method employed was the traditional one. From the results it was concluded that, although the behaviour of the four varieties do not vary significantly, one particular variety (“D. Joaquina”) is a good alternative to the “S. Bartolomeu” pear.     

卡尔费休库仑法测定熔结环氧粉末水分含量

通过对卡式炉温度、终点判定模式、滴定反应时间的实验分析研究,建立了卡尔费休库仑法测定熔结环氧粉末中水分含量的优化实验方法。实验条件为卡式炉温度100℃,延迟时间终止模式,滴定时间18 min。该方法适用于水分含量0.70%的熔结环氧粉末的水分测定,精密度实验相对标准偏差为1.14%,回收率范围为93.6%~99.4%。     

卡尔费休法测定尼龙66切片的含水量

针对前期使用卡尔费休法检测尼龙66切片含水量时存在较大实验偏差,与检测要求存在差距的问题,对载气种类、萃取时间、试样量、滴定度等影响因素逐一进行了分析和优化,得到了测定的最佳操作条件:萃取时间延长至1200 s,以使试样反应完全,提高检测平行性;对一定质量的试样,减少试样质量误差对测定结果产生的影响;根据试样含水量的大小,调节滴定度,保证仪器的最佳试剂消耗量。采取上述优化措施后,尼龙66切片含水量检测结果的平均偏差不大于5%,极大地提高了测量的准确率,达到了国标要求。     

原子吸收分光光度法测定过磷酸钙中铬含量

用原子吸收分光光度法测定过磷酸钙中铬含量。实验研究适宜的分析条件,结果表明:试液中加入w(K2S2O7)10%的焦硫酸钾溶液10mL作为抑制剂,加入盐酸(1+1)2mL控制酸性介质的酸度,测定准确度较高,回收率为93.6%～101.1%。     

丹参快速水分测定法的探究

探究丹参在实验室里利用快速水分测定法的实用价值,为实验室其它原料快速水分法的推广提供数据依据。利用快速水分与烘干水分做对照试验。在快速水分温度适宜的情况下实验数据与烘干的水分相一致。利用快速水分法代替烘干测定法测定原料水分,可以极大的提高测定速度,并提高了工作效率,节约了电力成本。