GZR型振动流化床在我厂的应用

目前国内制盐行业中已有少数厂矿选用了振动流化床作干燥湿盐的主体设备．本文翔实地介绍了川东盐厂在振动床应用和改进方面的经验和体会．     

振动流化床干燥机

由江苏正昌集团溧阳正昌干燥设备有限公司生产的TGZZ系列振动流化床干燥机具有下列主要特点：①采用振动电机驱动，运转平稳，维修方便，噪音低，寿命长；②物料在热风作用下，充分流化与热风接触，传热效率高，可获得均匀干燥物品；③根据物料的物理化学特性，可任意调节热风温度，节能效果显著，     

振动流化床干燥机在使用中存在的问题及其改造措施

本文主要阐述对振动流化床干燥机,存在问题的技术改造措施。     

TGZZ型振动流化床干燥机

近年来,我所参照英国西蒙公司和日本玉川机械株式会社样机,优化设计,完成了TGZZ系列振动流化床干燥机的试制工作。本文将着重介绍TGZZ振动流化床干燥机的原理、性能结构特点、节能因素和应用情况。     

振动流化闲及固定流化床的应用

阐述了奶粉生产过程中振动和固定流化床的用途及使用条件。并介绍了几种应用实例,为乳品行业进行3次干燥设计和老塔改造提出建议。     

采用振动流化床干燥卡拉胶的生产实践

将振动流化床干燥器应用于卡拉胶生产,结合卡拉胶干燥特性和流化床的结构特点,给出了干燥工艺的主要操作参数操作温度95~110℃,压榨程度含水82%以下,料层厚度进料5~6mm、出料1~1.5mm。     

大型振动流化床的应用与改进

由于大型振动流化床可节能，设备运行可靠，且物料在机体内的留存时间易于调节，所以在制糖工业中得到了广泛应用。尽管如此，振动流化床的开发与应用还有待于进一步完善和改进，本文以大型振动流化床干燥冷却白砂糖为例，对大型振动流化床实施了一些改进措施。将槽体由水平改为倾斜布置，以利于提高糖的通过量。同时分析了机体中的部件的弯曲振动所带来的危害，消除了筛板的弹性弯曲振动，提高了筛板的使用寿命，使整机的维护期延长，大大增加了大型振动流化床的使用寿命。     

盐用振动流化床干燥机的设计特点及应用研究

针对盐业生产的实际情况，设计开发了盐用振动流化床干燥机，并已在多家盐业企业投入使用，取得了良好效果。文中介绍了这种设备的设计特点、性能参数及现场使用情况。     

三聚氰酸毒理学研究进展

三聚氰酸是三聚氰胺的同类物,它与三聚氰胺在一定条件下形成结晶,在人和动物体内这种结晶易于对膀胱和肾脏造成损伤.本文对三聚氰酸的毒理学安全性资料(包括代谢、急性毒性、遗传毒性、亚慢性毒性、慢性毒性和致癌性)、与三聚氰胺的联合作用以及人群可能暴露水平进行综述.     

流化床法废盐酸再生技术在钢丝绳行业的应用

生产长材和板材的钢铁企业在生产过程中酸洗工序产生大量的工业废水,废水中含有金属离子和残留酸等有害物质,严重污染生产环境。介绍流化床法废盐酸再生技术应用在处理制绳钢丝废盐酸液上的技术特点、工艺流程及经济效益。引进的流化床法废盐酸再生成套机组和技术,每年可处理废盐酸约12 960 m3,回收率超过99.5%,再生盐酸浓度(体积分数)约18%,每年可创造经济效益173.4万元。节约了企业生产成本,符合循环经济的理念。     

盐用大型振动流化床漏料问题探讨

大型振动流化床在精制盐干燥过程中存在着漏料问题 ,直接影响产品质量和生产量。文章根据实验研究提出解决漏料的几种方案及改进措施     

A new approach to measure melamine, cyanuric acid, and melamine cyanurate using surface enhanced Raman spectroscopy coupled with gold nanosubstrates

Vibrational spectroscopic characteristics of melamine, cyanuric acid, and melamine cyanurate were measured using surface-enhanced Raman spectroscopy (SERS) coupled with gold nanosubstrates. Trace amounts of melamine and its analogues (cyanuric acid and melamine cyanurate) were characterized and quantified quickly and accurately by SERS in combination with partial least squares (PLS) analysis. Based on the relationship between the Raman intensity of the most prominent peak at around 676 cm⁻¹ and log values of melamine concentrations, the limit of detection (LOD) of SERS for melamine was estimated to be 2.6 × 10⁻⁷ mol L⁻¹ (∼33 ppb). An approximately 3 × 10⁴ fold of enhancement factor for SERS signals of melamine on gold nanosubstrates was obtained. This result was based upon the comparison of the peak at around 676 cm⁻¹ in the SERS spectra with that of normal Raman spectra of melamine in aqueous solutions. SERS spectra of cyanuric acid acquired from its solid form differ significantly from this compound in an aqueous solution, indicating a possible keto-enol isomerization reaction of cyanuric acid in water. When equal amounts of melamine and cyanuric acid were added together, spoke-like crystals of melamine cyanurate formed instantly, which could be measured and characterized by SERS. This study demonstrates that SERS could provide a fast and ultra-sensitive tool for detection and characterization of melamine and its derivative compounds in aqueous solutions.     

磁场稳定流化床反应器水解牛乳中乳糖的研究

在磁场稳定流化床反应器采用固定化β-半乳糖酶对牛乳中乳糖进行水解，研究了各种操作条件对牛奶中乳糖水解的影响，结果表明：在磁场强度14-18mT，牛乳流动速率小于14em^3／min、55℃的条件下水解牛乳120min，乳糖可水解86％。     

循环流化床中味精生长动力学的研究

在循环流化床上考察了过饱和度、温度、晶体粒度、晶种状况、添加剂对味精晶体生长的影响 ,获取了相应的动力学参数     

流化床结合大孔吸附树脂富集葡萄酒中的白藜芦醇

本文研究了自行搭建的流化床富集装置结合大孔吸附树脂对葡萄酒中白藜芦醇的富集方法。通过静态吸附实验比较了HPD826、DA-201、AB-8、H103和HPD600五种大孔吸附树脂的富集效果,进而筛选出最优吸附树脂,并将其应用于流化床中富集葡萄酒中的白藜芦醇。结果表明,流化床富集装置可确保流体均匀流动;大孔树脂可提高葡萄酒中白藜芦醇的富集效率,其中H103树脂的富集效果最优,吸附率达到94.00%;H103树脂动态吸附的最佳条件为酒样流速1.5 BV/h,保持酒样原液p H不变,解析条件为先水洗,再以1.0 BV/h流速、质量分数为80%乙醇溶液洗,酒样中白藜芦醇的吸附率可达89.4%,解析率为93.6%;经HPLC检测证明,在树脂量为0.0120 g,酒样流速为1.5 BV/h的条件下,流出液中基本不含白藜芦醇。      

Citric acid crystallization process in dense phase using vibrated bed

This study evaluated mass yield, in crystallization of citric acid on a vibrated bed, using a large seed population (dense phase). A stainless steel crystallizer, jacketed and trunk-conical shaped was used in the crystallization experiments. The shaking system consisted of two perforated disks coupled to a mobile axle, which was connected to an eccentric. A central composite design (CCD) was used considering three independent variables: supersaturation level, dimensionless vibration number, and crystallization time, while the seed population (100,000 U) and operation temperature (55 °C) were fixed. Optimization of the experimental data obtained in the CCD was done finding the condition of maximum yield, 164.7%, which was experimentally tested and resulted in yield of 187.7%. An experimental simulation of serial crystallizers was studied, obtaining 166.9% yield, which was effective for obtaining crystals of greater final dimension.     

Fluidized bed and tray drying of thinly sliced mango (Mangifera indica) pretreated with ascorbic and citric acid

The purpose of this work was to determine the influence of air temperature, sample diameter and antioxidants on water activity, moisture content and colour difference of thinly sliced mango in a fluidized bed and tray dryer. Mango samples were treated with antioxidants solutions (ascorbic and citric acid) before the drying process. Fluidized bed and tray drying of control and treated samples were carried out at two temperatures: 50 and 60 °C. A fractional factorial design 2^4?1 was used in both drying methods. The Newton semi‐theoretical model was found to represent thin‐layer drying kinetics of mango. For both drying types, moisture content of thinly sliced mango was well characterised (R² ≥ 0.975) by the model. The temperature increment increases the drying constant and decreases the equilibrium moisture content and water activity of the dehydrated samples. Colour closest to the original colour of fresh mango was obtained when 2 cm diameter mango pretreated with citric acid (1%) was dehydrated by fluidized bed at 60 °C. In addition, it was observed that the drying time at equilibrium by using fluidized bed was lower (60 min) than the tray dryer (120 min).     

Lipase-catalyzed production of pinolenic acid concentrate from pine nut oil using a recirculating packed bed reactor

Pinolenic acid (PLA) concentrate in fatty acid ethyl ester (FAEE) was efficiently produced from pine nut oil via lipase-catalyzed ethanolysis using a recirculating packed bed reactor (RPBR). The effects of reaction temperature, molar ratio, and residence time on the concentration of PLA were explored. Novozym 435 lipase from Candida antarctica showed less selectivity toward PLA esterified at the sn-3 position when temperature was increased from 45 to 55 °C. For the trials of molar ratio between 1: 50 and 1: 100 (pine nut oil to ethanol), there were no significant differences in the yield of PLA. Residence time of substrate in a RPBR affected significantly the PLA content as well as the yield of PLA. Optimal temperature, molar ratio (pine nut oil to ethanol), and residence time for production of PLA concentrate via lipase-catalyzed ethanolysis in a RPBR were 45 °C, 1: 50, and 3 min, respectively. Under these conditions, the maximal PLA content (36.1 mol%) in the concentrate was obtained during the initial 10 min of reaction.