新型干燥器在硫酸钡生产中的应用

在硫酸钡生产过程中,传统工艺采用的干燥设备是回转窑干燥器,其存在能耗高、污染环境、设备腐蚀严重等缺点.介绍了一种应用于硫酸钡干燥的新型高效节能环保型组合干燥装置--特制螺旋干燥器和特制盘式连续干燥器.阐述了新型干燥设备的工作原理及干燥工艺流程.分析了新型干燥设备应用于硫酸钡干燥过程所具有的特点,并与回转窑干燥设备在环保、节能等方面进行了比较.结果表明,在硫酸钡的干燥中,新型干燥设备热效率高,物料损失小,占地面积小,粉尘产生量极少,耗煤量小.     

间苯二甲酸双羟乙酯-5-磺酸钠的合成研究

采用间苯二甲酸二甲酯-5-磺酸钠(SIPM)和乙二醇(EG)为原料,在一定的温度和催化剂条件下进行酯交换反应制备间苯二甲酸双羟乙酯-5-磺酸钠(SIPE)。用高效液相色谱(HPLC)法测定酯交换率,系统研究了催化剂、EG／SIPM摩尔比及反应时间对酯交换率的影响。     

组合干燥系统在氰尿酸生产中的应用

本文通过对氰尿酸干燥前后物料性质的分析，提出了应用于氰尿酸干燥的气流一盘式连续干燥系统，介绍了这种组合设备的结构、工作原理，阐述了其工艺流程及工作特点，分析了这种组合形式的优势及应用领域，并通过与另外一种干燥器——厢式干燥器在工作效率、能耗、操作的连续性及干燥后产品的质量等方面的比较，表明了在氰尿酸干燥作业中这种组合干燥器是干燥设备的最佳选择。     

新型组合干燥器在镍精矿干燥中的应用

传统的回转窑等干燥设备在镍精矿的干燥上存在污染环境、能耗高及效率低等弊端,急切需要一种节能、环保、高效的干燥设备应用于镍精矿的干燥上。采用双桨叶干燥器和盘式连续干燥器组合干燥器对硫精矿进行干燥,通过25 d的半工业化试验,取得了成功,证明了此新型组合干燥设备在镍精矿干燥上的优越性,特别适合现在节能环保的要求,具有较大的社会推广意义。     

间苯二甲酸丙二醇酯-5-磺酸钠的合成工艺

以间苯二甲酸二甲酯-5-磺酸钠(SIPM)、1,3-丙二醇(1,3-PDO)为原料,采用酯交换法合成了间苯二甲酸丙二醇酯-5-磺酸钠(SIPP),并研究了催化剂种类及浓度、原料配比和反应温度对酯交换反应的影响。结果表明:通过工艺优化,当选择以钛酸四丁酯作为催化剂,其摩尔分数为0.1%(相对原料中SIPM的摩尔分数),1,3-PDO与SIPM的摩尔分数比为10.14∶1,反应温度为173℃时,酯交换反应速率较快且产物色泽良好。     

间苯二甲酸二甲酯-5-磺酸钠的合成研究

以间苯二甲酸为原料,经磺化,酯化,盐析得98%含量的间苯二甲酸二甲酯-5-磺酸钠,总收率82.6%.     

新型旋转式闪蒸干燥器

<正> 丹麦ANHYDRO公司近年推出了一种新型干燥器,称旋转式闪蒸干燥器(SPINFLASH DRYER),它不仅适用于无机化学品的干燥,也能应用于有机化学品的干燥,如某些有机颜料和染料、医药品及中间体等。作为一种新型干燥设备笔者特撰文介绍给同行们。 众所周知,迄今工业上采用的干燥器按其干燥的方式可分成三类: ①悬浮式直接干燥器,欲干燥的物质     

间壁式体积传热干燥器初探

叙述了间壁式体积传热干燥器传热原理及强化传热的途径。初步实验证明这种干燥器干燥速率大，可干燥各种粉状物料。由于干燥介质可循环使用，因而热能利用率高，是一种新颖的节能干燥设备     

盘式连续干燥器在棉籽饼粕干燥中的应用

介绍了应用于棉籽饼粕干燥的盘式连续干燥器 ,阐述了工作原理及工艺流程 ,分析了这种干燥形式的特点及应用领域 ,并重点与传统干燥器管束式干燥器进行了比较     

间苯二甲酸二甲酯-5-磺酸钠合成研究进展

综述了近20年来涤纶染色改性剂间苯二甲酸二甲酯-5-磺酸钠(SIPM)合成研究进展。将其制备方法分析归纳为磺酸结晶法、磺酸中和法、酯化磺化法、氯磺酸磺化法、"一锅煮法"5种,并对普通采用的"一锅煮"法的制备工艺及其工艺控制和产品质量分析方法进行了介绍,认为以间苯二甲酸(IPA)为原料,30％发烟硫酸为磺化剂,经磺化、酯化、中和和重结晶工艺是制备SIPM较佳的技术路线。     

PERFORMANCE STUDY OF A RE-CIRCULATING CABINET DRYER USING A HOUSEHOLD DEHUMIDIFIER

The performance and operating characteristics of a low temperature re-circulating cabinet dryer using a dehumidifier loop were studied using alfalfa. Chopped alfalfa, initially at 70% moisture content, was dried to 10% moisture content in the dryer. Two dryer setups were used. The dryers in each case had a partitioned cabinet with trays of material on one side and a stack of one or two small household dehumidifiers on the other side. Air was re-circulated through the material from bottom to the top and back through the dehumidifiers. Two drying configurations were tested. In one, the material was left on the trays until drying was complete (batch or fixed tray drying). In the other configuration, the trays were moved from top to bottom, introducing a new tray at the top while removing an old tray from bottom. Drying air temperature ranged from 25 to 45°C. The average air velocity through the material was 0.38 m/s. Alfalfa chops dried in 5 h in the fixed tray drying and in 4 h in the moving tray drying. The specific moisture extraction rate ranged from 0.35 to 1.02 kg/kWh for batch drying and stayed at an average value of 0.50 kg/kWh for continuous/moving tray drying.     

PERFORMANCE STUDY OF A RE-CIRCULATING CABINET DRYER USING A HOUSEHOLD DEHUMIDIFIER

ABSTRACT

The performance and operating characteristics of a low temperature re-circulating cabinet dryer using a dehumidifier loop were studied using alfalfa. Chopped alfalfa, initially at 70% moisture content, was dried to 10% moisture content in the dryer. Two dryer setups were used. The dryers in each case had a partitioned cabinet with trays of material on one side and a stack of one or two small household dehumidifiers on the other side. Air was re-circulated through the material from bottom to the top and back through the dehumidifiers. Two drying configurations were tested. In one, the material was left on the trays until drying was complete (batch or fixed tray drying). In the other configuration, the trays were moved from top to bottom, introducing a new tray at the top while removing an old tray from bottom. Drying air temperature ranged from 25 to 45°C. The average air velocity through the material was 0.38 m/s. Alfalfa chops dried in 5 h in the fixed tray drying and in 4 h in the moving tray drying. The specific moisture extraction rate ranged from 0.35 to 1.02 kg/kWh for batch drying and stayed at an average value of 0.50 kg/kWh for continuous/moving tray drying.     

盘式连续干燥器与回转窑干燥机干燥镍精矿的比较

介绍了盘式连续干燥器与回转窑干燥机的工作原理和干燥效果,通过对盘式连续干燥器的实验数据和回转窑的实际生产数据的分析比较,证明盘式连续干燥器干燥镍精矿的优越性及节能环保效果。     

提高氯气干燥效果的措施

阐述了在隔膜法烧碱生产过程中，因氯气含水多、干燥塔板积液和塔板上无泡沫层等造成氯气干燥效果不好导致酸流量调节困难，并影响设备使用寿命的问题。提出了具体有效的整改措施。     

硫铁矿生产硫酸中新型干燥设备的研究与开发

针对硫铁矿生产硫酸过程中硫铁矿干燥采用回转窑干燥法的缺点，设计了一种新型干燥装置——盘式连续干燥器。阐述了采用回转窑干燥器的干燥流程和采用盘式连续干燥器的干燥流程，以及盘式连续干燥器的结构和工作原理。重点介绍了盘式连续干燥器的选型及干燥性能。结果表明，新设备干燥能力大，热效率高，能耗低，调控性能好；产品质量好，物料无损失，对环境无污染。     

Investigation on the Effect of Condensing Moisture before Heating Air on the Performance of a Batch Tray Dryer: Application to the Drying of Vanilla

This article presents the results of an investigation of the effect of pre-dehumidifying the drying air before it is heated and supplied into a batch tray dryer. Dehumidification is achieved through moisture condensation as the air flowing through a coil is cooled by chilled water from a cold source. As an example, this process is applied to the drying of vanilla and is based on a numerical method already validated by former results. Then, it is established through comparisons with a conventional batch tray dryer model that pre-dehumidification significantly reduces drying time. Furthermore, preheating air by an intermediate heating source reduces total energy consumption of the primary heating system to a level depending on the preset drying temperature. As regards batch tray dryer design and optimization purposes, these results open up particularly interesting heating and cooling sources utilization prospects.     

Investigation on the Effect of Condensing Moisture before Heating Air on the Performance of a Batch Tray Dryer: Application to the Drying of Vanilla

This article presents the results of an investigation of the effect of pre-dehumidifying the drying air before it is heated and supplied into a batch tray dryer. Dehumidification is achieved through moisture condensation as the air flowing through a coil is cooled by chilled water from a cold source. As an example, this process is applied to the drying of vanilla and is based on a numerical method already validated by former results. Then, it is established through comparisons with a conventional batch tray dryer model that pre-dehumidification significantly reduces drying time. Furthermore, preheating air by an intermediate heating source reduces total energy consumption of the primary heating system to a level depending on the preset drying temperature. As regards batch tray dryer design and optimization purposes, these results open up particularly interesting heating and cooling sources utilization prospects.     

A Novel Design of Crop Dryer for Use in Developing Countries

The dryer is required for drying of grain as well as drying of the processed products in small catchment agro processing centers in the developing world. However, due to varied material characteristics of grain and secondary processed product, two entirely different types of dryers are required. The grain is dried in a recirculatory dryer, whereas processed product is dried in a tray dryer, where it is frequently mixed and trays are also intermittently changed. To avoid the need for two dryers, a novel design of a low-cost hot air dryer was developed where just by changing the trays the dryer can be converted from an LSU grain dryer to a tray-type product dryer. The dryer was tested for drying soybean grain as well as processed soy products like blanched soybean dal and soyflakes. The capacity of the dryer was 100 kg/batch in a tray dryer with each tray accommodating 10 kg of wet material. In case of LSU mode, the capacity of the dryer was 250 kg of grain per batch. The drying time required was 5 h for 250 kg of wet soybean from 24 to 10% moisture content, whereas in a tray dryer 100 kg blanched soybean dal was dried from 60 to 10% in 5 h and 100 kg of soyflakes from 25% moisture content to 10% moisture in 1.75 h. The cost of the dryer is estimated at US$580.00 and it can be fabricated in a moderately equipped workshop in developing countries.     

A Novel Design of Crop Dryer for Use in Developing Countries

The dryer is required for drying of grain as well as drying of the processed products in small catchment agro processing centers in the developing world. However, due to varied material characteristics of grain and secondary processed product, two entirely different types of dryers are required. The grain is dried in a recirculatory dryer, whereas processed product is dried in a tray dryer, where it is frequently mixed and trays are also intermittently changed. To avoid the need for two dryers, a novel design of a low-cost hot air dryer was developed where just by changing the trays the dryer can be converted from an LSU grain dryer to a tray-type product dryer. The dryer was tested for drying soybean grain as well as processed soy products like blanched soybean dal and soyflakes. The capacity of the dryer was 100 kg/batch in a tray dryer with each tray accommodating 10 kg of wet material. In case of LSU mode, the capacity of the dryer was 250 kg of grain per batch. The drying time required was 5 h for 250 kg of wet soybean from 24 to 10% moisture content, whereas in a tray dryer 100 kg blanched soybean dal was dried from 60 to 10% in 5 h and 100 kg of soyflakes from 25% moisture content to 10% moisture in 1.75 h. The cost of the dryer is estimated at US$580.00 and it can be fabricated in a moderately equipped workshop in developing countries.     

Heating Policies during the Primary and Secondary Drying Stages of the Lyophilization Process in Vials: Effects of the Arrangement of Vials in Clusters of Square and Hexagonal Arrays on Trays

The dynamic behavior of the primary and secondary drying stages of the lyophilization process were studied when (a) single vials located at different positions on the tray were individually being dried, and (b) the vials on the tray are arranged in clusters of square and hexagonal arrays and all the vials on the tray are simultaneously being dried. For both cases (a) and (b), fast drying times and relatively more uniform distributions of temperature and concentration of bound water at the end of the secondary drying stage are obtained by heat input control that runs the lyophilization process close to the melting and scorch temperature constraints. The heating control policies for the systems of case (b) are found to be more conservative and significantly more complex than those for the systems of case (a), because in case (b) there are vials on the tray that are in their secondary drying stage while other vials on the same tray have not yet completed their primary drying stage. Furthermore, the analysis and synthesis of the results presented in this work (i) indicate the minimum number of vials and their relative locations on the tray that have to be monitored by sensors so that the dynamic drying state of all the vials being dried simultaneously on the tray, could be satisfactorily determined in real time and appropriate, if necessary, control action could be applied, and (ii) suggest changes in the design of the freeze drying equipment so that the production rate of the freeze dryer could be improved and the product could also have enhanced properties of stability and quality at the end of the lyophilization process.