用蛋白酶蛋白质工程技术改进洗涤剂用酶的进展

为适应洗涤剂用酶的迅速发展,本文综述了用蛋白质工程的方法对Subtilisin进行定向改造情况,先后获得了具有抗氧化、高热稳定性、强耐碱性的突变体酶的改良菌种。     

国内洗涤剂用酶的研究

综述了国内洗涤剂用酶的研究、开发及应用情况，介绍了我国加酶洗涤剂生产概况及发展前景     

洗涤剂用酶—碱性脂肪酶的研究概述

综述了国内外洗涤剂用微生物碱性脂肪酶的去污增效原理,特性、主要生产碱性脂肪酶的微生物,厂家与发展情况以及提高微生物产酶水平及改造脂肪酶的主要技术手段。     

新型洗涤剂用酶--碱性脂肪酶的研究开发

该专题通过微生物菌种的定向筛选、高产碱性脂肪酶菌株选育、菌种放大生产和优化控制、提高提取收率开发了洗涤剂用碱性脂肪酶.产品具有安全、无毒、可降解特性,性能与国外产品相当.产品在洗衣粉中应用研究的成功,使我国实现双酶洗衣粉的国产化成为可能.     

碱性蛋白酶在液体洗涤剂中稳定性的研究

一、前言 自六十年代初酶被引入到洗涤剂后,酶在洗涤中的作用引起了人们的重视,尤其从七十年代以来,由于洗涤剂的限磷、禁磷及洗涤的低温化,更加速了酶在洗涤中的应用。至1992年,洗涤剂用酶已占世界工业酶产量的40％。 洗涤剂一般可分为固体和液体。液体洗涤剂由于其固有的优点,使它在一些国家     

微波辐射对洗涤剂用酶的作用

蛋白酶分别经过1000W微波辐射8s和10s后，在实验条件下，活性达到最大值，分别提高了11％和16％。加入标准粉后，二者去污比值几乎没有变化。微波辐射后的两种蛋白酶放置于室温下2个月，其活性均随时间变化而缓慢下降。脂肪酶分别经过1000W微波辐射5s后，活性达到最大值，分别提高了22％和7％。加入标准粉后，二者去污比值几乎没有变化。微波辐射后的两种脂肪酶放置于室温下4个月，活性均随时间变化回到未经微波辐射的最初状态。     

翅片导流板填料应用于旋转填料床的特性

For an alcohol/water system and with fin baffle packing, continuous distillation experiments were carried out in a rotating packed bed (RPB) system at atmospheric pressure. The effects of the average high gravity factor (β), liquid reflux ratio (R) and feedstock flux (F) on the momentum transfer and mass transfer were investigated. The gas phase pressure drop of RPB increased with the average high gravity factor, liquid reflux ratio and feedstock flux, which was 13.55-64.37 Pa at β of 2.01-51.49, R of 1.0-2.5, and F of 8-24 L&;#8226;h－1 for a theoretical tray in the RPB with fin baffle packing. The investigation on the mass transfer in the RPB with different packings showed that the number of transfer units of RPB with a packing also increased with the average high gravity factor, reflux ratio and feedstock flux. It is found that the fin baffle packing (packing III) presents the best mass transfer performance and lowest pressure drop for the height equivalent to a theoretical plate (HETP), which is 6.59-9.84 mm.     

表面活性剂对液体洗涤剂用蛋白酶储存稳定性的影响

通过在质量分数为30％的8种表面活性剂溶液中添加液体蛋白酶,考察不同温度条件下存放90d的过程中酶活性变化;研究了表面活性剂对酶储存稳定性的影响。结果表明：表面活性剂对酶储存稳定性的影响程度因表面活性剂的品种不同而各有差异,其中AE09、6501、AEC对酶的活性影响程度弱;LAS、AOS、APG12～14对酶的活性影响程度强;TX-10、AES对酶的作用居中。温度对酶储存稳定性有显著影响,建议在35℃以下储存为宜。     

高效填料塔成套分离工程技术

以总体方案、模拟计算、工艺流程、汽液传质设备、安装开车等５个基本工程步骤为线索，从工业应用角度，综述性地介绍高效填料塔成套分离工程技术的国内应用水平和发展趋势。     

不同填料旋转填料床废水气提效果研究

为了探索旋转填料床中不同填料对废水中丙烯腈去除率的影响,并为超重力气提丙烯腈废水工艺优选合适的填料提供参考,分别在装有填料A和填料B的旋转填料床中进行气提丙烯腈废水的实验。在相同的工艺条件下对比考察了填料A和B对丙烯腈去除率的影响。结果表明:在实验操作条件范围内,填料A和B的丙烯腈去除率均可达60%以上;更换高效的填料有助于丙烯腈去除率的提高,且气液比对丙烯腈去除率的增幅影响最为显著,超重力因子β次之;与填料A相比,仅考虑丙烯腈废水处理效果和处理成本,填料B更适用于超重力气提工艺中的旋转填料床。研究结果为选取适宜的旋转填料床填料以及超重力气提工艺的工业化应用提供一定依据。     

旋转填料床连续精馏实验研究

The performance of a rotating packed bed （RPter solutioB） with three kinds of packings was investigated using alcohol/wan under continuous distillation conditions at atmospheric pressure. The effects of average high gravity factor （β）, reflux ratio （R）, and feedstock flux （F） on mass-transfer in distillation were examined separately. Experimental results indicated that the total number of theoretical units （NTU） of RPB increased with β, R, and F.Of the three kinds of packings, the wave thread packing of stainless steel （Packing-Ⅲ）-had the best mass transfer efficiency with the height equivalent of a theoretical plate （HETP） of approximately 7.35 mm- 23.58 ram, whereas the corrugated disk pacing of stainless steel,（Packing Ⅰ） had the worst one with the HETP of about 13.4 mm-48.07 mm.Correlations were cleveloped to describe the mass transfer efficiency for packings Comparing.experimental data with the data calculated by correlation, the average deviate obtained for each packing was 0.72%, 1.98%, and 2.7%, respectively, implying that the accuracy of correlations developed was reasonable.     

超重力旋转床脱除微米级粉尘的实验研究

用超细滑石粉模拟工业微米级粉尘,通过实验研究了超重力旋转床的除尘特性.考察了旋转床在不同的气量q<,G>、液量q<,L>、转速n和轴向放置平面丝网层数n<,m>下的除尘效果,确定了实验室规模下适宜的除尘工艺条件:q<,G>=600 m<'3>/h,q<,L>>0.6 m<'3>/h,N=1 400 r/min,n<,m...     

大开孔率填料支承装置填料洗涤塔的设计与工业应用

介绍了填料洗涤塔的塔体、填料、填料支承装置和液体分布装置的结构和设计.目前已有数十套使用组合式液体分布装置和大开孔率填料支承装置的填料洗涤塔在运行中,最大塔径达4 800 mm,工业生产装置的实测数据表明,填料洗涤塔的烟气出口温度与进塔的液相温度相差1.5～2.0 ℃,填料洗涤塔的气相压力降为500～700 Pa.     

Distillation studies in rotating packed bed with split packing

Rotating packed bed (RPB) with split packing has been developed recently to overcome the limitation of negligible tangential slip velocity between vapor and packing obtained with single rotating packing element of conventional RPB design. This work evaluates the performance of this contactor for separation of binary mixture methanol–ethanol by distillation. Experiments were carried out at total reflux condition. The height equivalent of a theoretical plate (HETP) of 2.9 cm was obtained at F-factor = 0.6 (m/s) (kg/m³)^0.5 and rotor speed of 1100 rpm. Comparison with distillation studies reported for this system in the literature indicated that the mass transfer performance of this rotor design was superior to that of conventional RPB. Analysis of the experimental data also suggested that the rotor speed influenced the overall volumetric mass transfer coefficient to a greater degree in this design.     

填料塔技术的现状与展望

介绍了填料塔和塔填料的发展史、现状和工业应用情况；分析了填料塔内流体流动与分布、传质过程中的返混现象和传质动力学等理论研究中的若干技术问题，并指出了今后的研究方向。