节杆菌LF-Tou2产生絮凝剂的培养及去除重金属的作用研究

节杆菌LF-Tou2在混合糖源的培养基中12h就能达到对数生长后期,产生的絮凝剂为多糖物质。在分批补加培养30h时多糖物质的产生达到顶峰,为6．06g／L。絮凝剂的产生与细胞生长同步。与分批培养相比,分批补加培养的多糖生成率由27．8％提高到33．7％,单位体积内多糖产量提高了1．18倍。在试验浓度下Fe^2 、Mn^2 、Hg^2 及Ni^2 在细胞培养中的去除率均为100％,Cu^2 对细胞的初始生长及絮凝剂的形成都有明显的抑制作用。絮凝剂培养物对Fe^2 和Mn^2 的絮凝去除率非常高,分别达到100％、93．86％。     

番茄粉生产的干燥技术

简要介绍了番茄粉生产的工艺流程,系统讨论了番茄酱的三种非常规喷雾干燥技术特点,并对番茄粉生产的几种组合喷雾干燥工艺流程进行了综合评述。     

焦化苯塔精馏过程的计算机模拟

简述了焦化苯塔的工艺及参数,介绍了相关数学模型的选择及模拟计算,并对结果进行了讨论,通过模拟可以优化工艺条件,建议在实际生产中应经常应用模拟系统,实现系统在线的模拟、修正与系统的优化。     

Crystallization and Drying of Milk Powder in a Multiple-Stage Fluidized Bed Dryer

The rationale of this study has been to use fluidized beds to crystallize amorphous spray-dried skim milk powders with multiple stages of processing at different temperatures and humidities with the aim of rapidly making mostly crystalline powders. This paper discusses the performance of a multiple-stage fluidized bed dryer, and a combination of crystallization of lactose in spray drying at high humidity (lactose nuclei formation) and subsequent fluidized bed drying. Two different combinations of spray dryer and multi-stage fluidized-bed dryer have been suggested to crystallize lactose in skim milk powder. The results show significant improvements in the crystallinity of the powders. Moisture sorption test and X-ray diffraction analysis were used to assess the crystallinity of the powders. The processed powders that were crystallized in a humid-loop spray drying combined with a two-stage fluidized-bed dryer/crystallizer showed 92% improvement in lower amorphicity by processing at different stages of 70°C, 50% RH and 80°C, 50% RH for 15 minutes. The conventionally spray-dried powders that were crystallized in a three-stage fluidized-bed dryer/crystallizer showed 87% improvement in lower amorphicity (less moisture sorption) by processing at different stages of 60°C, 50% RH; 70°C, 40% RH; and 80°C, 40% RH for 20 minutes. The multiple-stage fluidized bed system showed distinctive potential to crystallize lactose significantly in skim milk powder using an industrial-feasible process.     

我国洗衣粉市场现状与生产特点

对国内洗衣粉的发展与市场现状作了简单的介绍,结合正在建设的合肥利华洗涤剂有限公司20万吨/年洗衣粉装置对洗衣粉生产的技术特点、主要操作技术指标进行了简单的描述.     

80kt／a硫酸装置干吸塔的设计

介绍铜化贵金属冶炼厂８０ｋｔ／ａ烟气制酸干吸塔（４０００ｍｍ×１４４００ｍｍ）的设计概况,选材、气液分布装置、填料的材质和规格、填料的支承装置,捕沫装置。设计中重点考虑减小塔阻力、改善气液传质,防腐蚀,延长设备使用寿命。     

焦粉回配炼焦工艺的实验研究

介绍了在 2 0 kg实验焦炉上进行的焦粉回配炼焦工艺实验 ,实验结果表明 :在生产设备中添加适量的焦粉进行炼焦是可行的 ,并分析了焦粉的粒度和焦粉的配入量对焦炭质量的影响 ,最终认为在炼焦生产中配入3%～ 5 %的焦粉是一种可行的工艺。     

焦炭塔法兰应力分析计算

采用有限元分析软件ANSYS,对焦炭塔法兰在设计条件下的应力进行分析计算,依据JB4732-95对其进行强度校核。分析计算结果可知,该法兰强度符合要求,设计合理。     

焦炭塔顶油气管嘴破坏原因分析与处理

文章介绍了焦炭塔顶油气管嘴破坏原因分析与处理。通过对焦炭塔顶油气管嘴破坏原因分析,对其进行处理,不仅可有效防止焦炭塔顶油气管嘴产生裂纹,同时提高了焦化装置的整体安全性,避免了焦化装置在正常运行过程中,装置停车带来的经济损失。     

Spray Drying of Skim Milk Mixed with Milk Permeate: Effect on Drying Behavior, Physicochemical Properties, and Storage Stability of Powder

The possibility of using milk permeate (MP) to lower the protein level of skim milk powder (SMP) in producing powders of 34% and lower protein is explored. Skim milk suspensions with various levels of MP were prepared by mixing SMP and MP powder (MPP) at the ratios of 1:0, 7:3, 3:7, and 0:1: from 34 to 5.3% protein. The suspensions were dried in a spray dryer with inlet and outlet temperatures of 180 and 80°C, respectively. Increasing permeate concentration in the mixture showed a greater tendency to stickiness manifested by lowered the cyclone recovery of the powder as more powder stuck on the wall of the dryer. Increasing permeate concentration in the resultant powder did not significantly affect the bulk density but led to a reduction in the particle size and also made the powder slight green and yellowish in color. It also found to lower the glass transition temperature (T_g) of the skim milk powder (SMP) and induce crystallization of lactose at lower water activity (a_w ≥ 0.328 for SMP:MPP of 3:7 and 0:1 compared to a_w ≥ 0.0.432 for SMP:MPP of 1:0 and 3:7). Addition of MP in SMP lowered the T_g values of the resulting powders. The permeate fraction in spray-dried SMP/MPP mixtures found to lower the critical a_w and moisture content, suggesting the SMP mixed with MPP is more likely to become sticky than SMP alone (at 34% protein) when stored at a similar water activity and moisture content.     

Spray Drying of Skim Milk Mixed with Milk Permeate: Effect on Drying Behavior,Physicochemical Properties,and Storage Stability of Powder

The possibility of using milk permeate (MP) to lower the protein level of skim milk powder (SMP) in producing powders of 34% and lower protein is explored. Skim milk suspensions with various levels of MP were prepared by mixing SMP and MP powder (MPP) at the ratios of 1:0, 7:3, 3:7, and 0:1: from 34 to 5.3% protein. The suspensions were dried in a spray dryer with inlet and outlet temperatures of 180 and 80°C, respectively. Increasing permeate concentration in the mixture showed a greater tendency to stickiness manifested by lowered the cyclone recovery of the powder as more powder stuck on the wall of the dryer. Increasing permeate concentration in the resultant powder did not significantly affect the bulk density but led to a reduction in the particle size and also made the powder slight green and yellowish in color. It also found to lower the glass transition temperature (T_g ) of the skim milk powder (SMP) and induce crystallization of lactose at lower water activity (a_w  ≥ 0.328 for SMP:MPP of 3:7 and 0:1 compared to a_w  ≥ 0.0.432 for SMP:MPP of 1:0 and 3:7). Addition of MP in SMP lowered the T_g values of the resulting powders. The permeate fraction in spray-dried SMP/MPP mixtures found to lower the critical a_w and moisture content, suggesting the SMP mixed with MPP is more likely to become sticky than SMP alone (at 34% protein) when stored at a similar water activity and moisture content.