新型聚乙烯烧结膜微滤设备及其在硬质合金磨削液集中净化处理中的应用

介绍了新型聚乙烯(PE)烧结膜微滤设备的结构和性能特点及其工作原理和技术参数.在工业生产过程中分别采用PE烧结膜微滤设备和无机陶瓷膜微滤设备集中净化处理硬质合金水基磨削液.结果表明,在40 m3/h过滤流量和1 μm过滤精度下,PE烧结膜微滤设备只须采用简单的"终端过滤+反吹/反洗"防污堵措施,就能保证连续运行3个月而不出现流量衰减迹象.与无机陶瓷膜微滤设备相比,PE烧结膜微滤设备更具经济性和环保性,完全能满足硬质合金磨削液集中净化处理的要求.     

《过滤介质及其选用》简介

《过滤介质及其选用》是由王维一、丁启圣等编著,中国纺织出版社于2008年5月出版的新书。全书共11章,43.3万字,8版彩页。本书详细论述了液-固、气-固及特殊过滤用的各类主要介质的品种、性能、工作原理及其生产制备。内容包括滤布用合成纤维、滤布、滤纸、滤片、滤筛、滤网、滤芯组件、松散粉末、纤维、颗粒介质、膜和膜组件、多孔片和多孔管等。     

过滤装置中的滤料

本文介绍了过滤装置由滤料组成的滤层的过滤机理，滤层的选用及冶金工业常用的中、高速过滤器的技术参数及滤层截污能力，过滤水含油控制等方面的资料，对设计和使用过滤装置有一定的帮助。     

轻质滤料在水处理中的应用

本文对新型过滤材料——聚苯乙烯轻质滤料用于原水直接过滤,对不同的滤层、进水浊度、滤速、投药量以及不同反应时间下的过滤,进行了较系统的实验研究,对实验中的各种现象进行了分析,提出了过滤运行受浊质粒子附着和深入滤层两个影响因素的观点,并由此得出过滤运行的结论。     

用内滤式过滤机过滤重物料

我厂的铁矿渣过滤曾采用过外滤式和内滤式真空过滤机。经过几年来的生产实践证明,对较重物料的过滤,内滤式真空过滤机的过滤效率远远超过外滤式过滤机。我厂采用的内滤式过滤机过滤面积为8米~2,过滤面有效尺寸为内径2370毫米,长1000毫米;滤鼓浸入悬浮液中的角度为115°,过滤区角度为82°,再生区角度(吹风区角度相同)为25°,洗涤与干燥区角度为124°;     

反渗透处理技术在太钢生产废水回用中的应用

钢铁企业生产废水成分复杂，水质不稳定，利用膜处理技术回收废水难度较大。太钢企业生产废水经过曝气、加药混凝、沉淀、多介质过滤、微滤、保安过滤后，达到反渗透膜进水要求，经一级、二级反渗透处理后，达到除盐水水质标准，节约了水资源。     

金分析中抽滤吸附过滤难的问题探讨与研究

针对金分析中抽滤吸附过滤难的问题，采用取矿样溶液中加入F^-或过滤前向试液中加入凝聚剂的处理方法，不仅解决了抽滤附过滤难的问题，而且还大大地提高了分析结果的准确度。     

环冷水底滤法高炉渣处理工艺设计

详细介绍了环冷水底滤法高炉渣处理工艺,从冲渣沟、过滤池两方面着手介绍了环冷水底滤法高炉渣处理工艺设计的主要内容,并以实例说明了环冷水底滤法高炉渣处理工艺操作。     

采用电沉积的新过滤技术

将真空过滤与电沉积联合过滤超细物料的滤浆,能大大地节能和降低成本。     

用真空泵排气代替鼓风机吹落滤并

长期以来,在精矿过滤作业中,通常使用往复式真空泵或水环式真空泵抽吸滤液形成滤并,然后使用水环式压气机、罗茨鼓风机,高压串联离心鼓风机或往复式空压机经储气罐降压后的低压空气吹落滤并。各种型式的过滤     

复合管膜的润湿性及过滤污水机理

为了研究多孔复合管膜对钢铁产业污水的过滤性能及其过滤机理,采用静滴法做了水滴和油滴在复合管膜上的润湿性研究。采用扫描电镜、EDS等手段分析了使用前后的多孔复合管膜外壁及内壁的结构及成分,分析了含油污水中固体颗粒及油的过滤机理,并利用视频光学接触角测量仪测量水滴和油滴在复合管膜上接触角随时间的变化速率。结果表明,在污水过滤过程中,水中小于管膜表层微孔孔径的氧化铁等杂质进入复合管膜内部,无法随水流穿过复合管膜膜层,积累在管膜内部;随着管膜使用时间延长,氧化铁等杂质在复合管膜内部积累量增多。水在复合管膜上的润湿性良好,油滴在复合管膜上是不润湿的。     

膜技术处理重金属废水

文章论述了重金属离子的危害性、膜技术优点,同时阐述了反渗透、微滤、超滤、纳滤、液膜分离技术在重金属废水中的研究和应用情况.     

Municipal Wastewater Treatment Using a UASB Coupled with Cross-Flow Membrane Filtration

A pilot scale up-flow anaerobic sludge blanket (UASB) coupled with cross-flow membrane filtration was used to treat low strength municipal wastewater in Singapore. The application of membrane filtration as a polishing unit of UASB effluent could produce better effluent quantity than conventional UASB. In this research, with gradually reducing hydraulic retention time from 10.0?to?5.5?h, membrane effluent was able to meet the more stringent effluent criterion over the whole experiment. Simultaneously, biogas yield increased from 61.8?to?120.7?mL/g CODremoved, in which methane percentages were also increased from 59.3 to 65.2%, respectively. Furthermore, the results of anaerobic membrane filtration showed that there were three different methods could effectively mitigate rapid membrane fouling and maintain trans-membrane pressure as low and stable as possible. These would reduce membrane cleaning frequency and prolong membrane life span.     

陶瓷膜在氢氧化铝微粉生产中的应用

工业上,氢氧化铝微粉生产一般采用板框或盘式过滤器洗涤,存在耗水量大、设备运行不稳定、操作繁琐等问题。本文在传统工艺之前增加无机陶瓷膜过滤,以错流过滤方式对浆料进行预浓缩研究,考察陶瓷膜设备在氢氧化铝生产中高浓度氢氧化钠、高温度、高固体含量体系中的运行情况,为现有工艺提供改进依据和数据。实验结果证明,新工艺很好地解决了前述问题。     

多孔金属陶瓷膜研究进展

以多孔金属为基体的陶瓷膜具有力学强度高、过滤精度高和耐高温耐腐蚀等优点,已广泛应用于过滤、分离等领域。通过对比国内外多孔金属陶瓷膜的发展现状,综述了多孔金属陶瓷膜的结构特点、制备方法、对多孔金属基体的要求、研究现状和发展趋势,重点介绍了以多孔金属为基体的Ti O2和Al2O3膜的制备和研究。     

陶瓷膜孔道内尘粒沉积及脱附的模拟

陶瓷膜是过滤高温含尘烟气最有效的材料之一,其过滤性能和再生性能与尘粒在陶瓷膜孔道内的沉积和脱附机制相关。本文建立了不同孔隙率的陶瓷膜物理模型,然后结合连续性方程、动量方程和能量方程,设定边界条件以及沉积条件,模拟了陶瓷膜过滤和脉冲反吹时,高温烟气的流动以及尘粒的沉积与脱附过程。结果表明,过滤速度较低和陶瓷膜孔隙率较高时,尘粒易于沉积在陶瓷膜孔道内;脉冲反吹时,增加反吹压力,延长反吹时间,尘粒易于从陶瓷膜孔道脱附。采用厚度为20 mm,长度为1.5 m,孔隙率为40%的陶瓷膜管过滤温度为1000 ℃,流速为1 m·min?1,压力为0.1 MPa的含尘烟气时,反吹气压力应不低于0.3 MPa,反吹时间不短于0.02 s,尘粒脱附时间在13 s,脉冲反吹时间间隔应高于452 s。      

Glomerular mesangial cells: electrophysiology and regulation of contraction

Mesangial cells are smooth muscle-like pericytes that abut and surround the filtration capillaries within the glomerulus. Studies of the fine ultrastructure of the glomerulus show that the mesangial cell and the capillary basement membrane form a biomechanical unit capable of regulating filtration surface area as well as intraglomerular blood volume. Structural and functional studies suggest that mesangial cells regulate filtration rate in both a static and dynamic fashion. Mesangial excitability enables a homeostatic intraglomerular stretch reflex that integrates an increase in filtration pressure with a reduction in capillary surface area. In addition, mesangial tone is regulated by diverse vasoactive hormones. Agonists, such as angiotensin II, contract mesangial cells through a signal transduction pathway that releases intracellular stores of Ca2+, which subsequently activate nonselective cation channels and Cl- channels to depolarize the plasma membrane. The change in membrane potential activates voltage-gated Ca2+ channels, allowing Ca2+ cell entry and further activation of depolarizing conductances. Contraction and entry of cell Ca2+ are inhibited only when Ca2+-activated K+ channels (BK(Ca)) are activated and the membrane is hyperpolarized toward the K+ equilibrium potential. The mesangial BK(Ca) is a weak regulator of contraction in unstimulated cells; however, the gain of the feedback is increased by atrial natriuretic peptide, nitric oxide, and the second messenger cGMP, which activates protein kinase G and decreases both the voltage and Ca2+ activation thresholds of BK(Ca) independent of sensitivity. This enables BK(Ca) to more effectively counter membrane depolarization and voltage-gated Ca2+ influx. After hyperpolarizing the membrane, BK(Ca) rapidly inactivates because of dephosphorylation by protein phosphatase 2A. Regulation of ion channels has been linked casually to hyperfiltration during early stages of diabetes mellitus. Determining the signaling pathways controlling the electrophysiology of glomerular mesangial cells is important for understanding how glomerular filtration rate is regulated in health and disease.     

氧化铝生产洗涤用陶瓷超滤膜制备工艺的研究

首先以球形氧化铝为原料,加入黏结剂、增塑剂和水后充分混合,经炼泥、挤压成型工艺制备支撑体坯件,坯件经干燥、烧结工艺制备陶瓷支撑体;然后,以球形氧化铝为原料,采用悬浮液浸涂法在陶瓷支撑体上涂膜,经烘干后形成过渡层;最后,以铝盐为原料,采用溶胶-凝胶法在过渡层表面涂覆溶胶制膜液,将湿膜晾干、烘干、焙烧,自然降温得到氧化铝生产洗涤用陶瓷超滤膜。研究结果表明:该陶瓷超滤膜顶膜孔径50~200 nm,无裂纹和针孔等缺陷,抗压强度高于10 kg×cm~(-2),抗弯强度高于8 kg×cm~(-2)。由此可见,该工艺制备的氧化铝生产洗涤用陶瓷超滤膜颗粒均匀,具有良好的化学稳定性、耐腐蚀、耐高温、耐酸碱,可在氧化铝生产洗涤领域推广和应用。     

The determination of benzalkonium chloride in eye-drops by difference spectrophotometry

Faecal samples from 94 dairy cows and 42 calves in three different herds were examined by a variety of techniques for campylobacters. Cefoperazone amphotericin teicoplanin (CAT) agar, modified cefoperazone charcoal deoxycholate agar (mCCDA), Karmali agar, and membrane filtration onto blood agar, were used with and without enrichment in CAT broth. Seventy-nine percent of cattle in herd A carried campylobacters, compared with 40% and 37.5% of cattle in herds B and C, respectively. Most animals carried only one species of Campylobacter. Campylobacter hyointestinalis was isolated most frequently (32% animals positive) with Camp. fetus subsp. fetus and Camp. jejuni subsp. jejuni detected in 11% and 7% of animals, respectively. In addition, a novel biotype of Camp. sputorum was isolated from 60% of 47 cows tested in herd A. Direct plating detected only two of the total of 40 animals positive for campylobacter. Enrichment in CAT broth before membrane filtration onto blood agar or CAT agar were the most successful methods of plating. Campylobacter sputorum was isolated from CAT agar and blood agar but not from mCCDA or Karmali agar. Karmali agar incubated at 30 degrees C was especially effective for isolating Camp. fetus subsp. fetus.     

Mucilages in succulent plants

A comparison has been made among some methods (concentration on aluminium hydroxide precipitates, polymer two-phase separation, cellulose membrane filtration, direct inoculation) for virus isolation from raw sewage. The concentration on aluminium hydroxide has given significantly better results than the other methods. No significant differences have been noted between the two-phase separation and direct inoculation method. The membrane filtration method has given no positive result. All isolated viruses belonged to the adenovirus group.