炭膜处理含油污水的研究

用不同孔径的炭膜对乳化含油污水进行处理,考察了跨膜压差,原料液浓度以及进料流量对膜渗透通量的影响,比较了不同的清洗剂对膜通量的恢复效果,给出了恢复膜通量的精洗方法。     

鞣质、果胶污染膜的清洗初步研究

采用常用的膜的清洗方法及清洗剂,清洗被鞣质、果胶污染后的中空纤维膜。结果表明,用几种清洗剂依次交替清洗,能使膜通量有较好的恢复,且实验重复性好。     

油水乳液污染纳米TiO_2改性Al_2O_3陶瓷膜的化学清洗

研究了采用碱性复合清洗剂通过一次清洗工艺对油水乳化液污染的纳米TiO2改性Al2O3陶瓷微滤膜进行化学清洗的可行性.通过通量恢复率、油截留率、SEM和FT-IR等分析手段表征了制备的复合清洗剂对改性陶瓷膜的清洗效果及化学清洗对纳米TiO2改性效果的影响.结果表明,采用制备的复合清洗剂对油水乳化液污染的改性陶瓷膜进行清洗后,可有效去除膜污染物,表现出良好的清洗效果,且清洗过程不会明显影响纳米TiO2对Al2O3陶瓷膜的改性效果.工业应用试验表明,冷轧乳化液含油废水污染的改性陶瓷膜,经碱性复合清洗剂清洗后,膜纯水通量恢复率和油水渗透通量恢复率分别可达到96.9%和98.1%.     

膜的污染及其清洗

综述了膜污染的机理及其影响因素，膜的清洗方法及常用的清洗剂，然后根据这些原则清洗中空纤维膜超滤红霉素板框滤液引起的膜污染，得到适合该情形的好的清洗剂，只须用三种化学清洗剂交替清洗，结合清洗技巧，很快膜通量恢复，实验重复性好。本文的清程序和方法可指导膜过滤过程膜污染的清洗。     

超滤法提纯茶多酚的研究

对比考察了几种不同膜材质、不同截留分子量和不同构型的膜系统对茶叶水提液中茶多酚的分离效果,比较了不同清洗剂对膜污染的清除效果.结果表明,Ultra-flo超滤系统适于茶多酚的提纯,尤其是聚偏氟乙烯膜UF-602-5和聚砜膜UF-610,膜通量较大,茶多酚透析率高.膜污染后,碱性清洗剂对茶叶污染物具有一定的去除能力,酸性清洗剂几乎没有任何效果,氧化性清洗剂去污性虽很强,但易对膜造成损伤.选用UF-602-5膜连续做了5个批次的重复超滤实验,结果显示,加水套洗可提高茶多酚的收率,改善分离效果,但随实验批次的增加,膜通量逐渐衰减.     

油水污染炭膜清洗方法的放大实验研究

采用自制的孔径为0．6～2．5μm的单根和多根管状炭膜，用原油和水经超声波乳化而成的油水乳化液为原料，用不同的清洗方法及清洗条件，通过比较膜的通量恢复率，考察单管和七管规模下的清洗规律．实验结果表明，在单管和七管条件下，用单一清洗剂清洗的效果都不理想；而采用酸洗和碱洗的组合清洗方式效果较好；为达到满意的清洗效果，七管时清洗剂的浓度需要比单管时增加一倍；清洗时间加长为单管的2．5倍．这些数据可为在工业规模下炭膜的清洗恢复提供依据．     

农药废液处理工艺中反渗透膜污染与清洗研究

以农药废液处理工艺中的反渗透膜为研究对象,通过表观分析、烧失量分析、扫描电子显微镜与能谱仪(SEM-EDS)、傅里叶红外光谱仪(FTIR)、X射线衍射仪(XRD)分析和表征反渗透膜的污染状态,通过不同清洗实验探讨膜通量恢复率并确定最优清洗方案.结果表明,膜污染由有机污染和无机污染组成,有机污染占总污染的50%左右,主要来源于废液中的二甲戊灵、灭草松、灭菌唑等农药有效成分;无机污染主要为Ca、Mg、Al的无机盐、硅酸盐和少量的磷酸盐.最优清洗方案为专用碱性清洗剂+十二烷基苯磺酸钠+专用酸性清洗剂的组合,膜通量恢复率达86%.     

聚醚砜膜提纯乳糖的研究

以聚醚砜(PES)为膜材料,聚乙烯吡咯烷酮(PVP)为添加剂,N,N-二甲基乙酰胺为溶剂,采用相转化法制备了对PEG的截留分子量为20 000的聚醚砜超滤膜.通过对操作压力、料液的温度和浓度等条件的变化对蛋白质截留率、膜通量及乳糖透过率影响的分析,研究了不同的影响因素对乳糖超滤效果的影响规律.并确定了最佳工艺条件:压力在0.3 MPa左右较适宜,温度为50~60℃,料液浓度为100~150 g/L,处理时间为45~60 min.比较了不同清洗剂对PES膜超滤性能恢复的效果.结果显示,当超滤1 h通量减少一半时,用0.5%的NaOH清洗20 min后就可以恢复70%的膜通量.     

陶瓷膜技术在再造烟叶萃取液预处理中的应用

通过陶瓷膜技术对造纸法再造烟叶萃取液进行预处理,降低料液中的不溶物含量.考察了陶瓷膜孔径和操作压力对处理过程的影响,并开展了连续稳定性实验,考察不同清洗剂对陶瓷膜通量恢复的影响.结果表明,20nm的陶瓷膜分离效果最好,透过液中不溶物含量仅为0.013%;优选陶瓷膜操作压力为0.3 MPa,以达到较高的通量.此外,在连续稳定性实验中得知,水洗0.5 h+1%NaOH溶液清洗1 h+水洗0.5 h+1%HCl溶液清洗1 h+水洗至中性是最好的清洗方法,膜通量恢复良好.     

红霉素发酵液纳滤膜污染与再生

超滤-纳滤双膜法作为新型分离技术应用于红霉素发酵液的过滤和浓缩.双膜法是指行先用陶瓷或金属超滤膜对发酵液进行预处理,之后树脂脱色,再进入纳滤膜浓缩.详细分析与总结了纳滤膜的膜污染,根据污染物的特性,选用专业清洗剂和清洗方法,给出最佳的再生方案:在0.37MPa,38~45℃下,采用专业清洗剂碱酸清洗法清洗和定期采用酶碱酸清洗法相结合的清洗方法.在保持同样通量下,专业清洗剂清洗后的一级膜进口压力比片碱、柠檬酸清洗后的一级膜进口压力降低约20%.     

Multi-pollutants simultaneous removal from flue gas

The multi-stage humidifier semi-dry flue gas cleaning technology, the CRS plasma flue gas cleaning technology and oxidative additive flue gas cleaning technology were investigated for multi-pollutants removal. The semi-dry flue gas cleaning technology using multistage humidifier and additive can improve oxidation and absorption, and it can achieve high multi-pollutants removal efficiency. The CRS discharge can produce many OH radicals that promote NO oxidation. Combining NaOH absorption can achieve high deSO2 and deNOx efficiencies. It is very fit of the reconstruction of primary wet flue gas desulfurization (WFGD). In addition, Using NaClO2 as additive in the absorbent of WFGD can obtain very high removal efficiency of SO2 and NOx.     

等离子体清洗工艺对镁基金属表面形貌及膜／基结合强度的影响

采用不同等离子体清洗工艺对镁基金属样品进行清洗,随后磁控溅射沉积纯Cr镀层.利用SEM、划痕仪分析了不同等离子体清洗工艺下镁基金属的表面形貌与膜／基结合强度的变化.结果表明,过高的清洗偏压作用下,基体表面会产生深径比＞0.5的孔洞状结构缺陷;过长清洗时间后,离子轰击产生的能量积淀效应使基体表面温升显著,局部区域出现熔融...     

超声清洗法回收冷轧厂磁过滤物中的纳米铁粉

研究一种冷轧厂磁过滤物中纳米铁粉的回收方法,采用超声清洗法除去铁粉表面的油污,得到纯净的纳米铁粉,通过试验研究超声频率、功率密度、清洗温度对除油效果的影响,采用X射线衍射和扫描电子显微镜对铁粉产品进行表征。结果表明,相对于机械搅拌清洗,采用超声清洗含油铁粉,可提高清洗液的除油能力;超声频率为40 kHz,功率密度为0.44 W/cm2,清洗温度为40℃时,用清洗液清洗4次,每次清洗时间为20 min,用去离子水漂洗至澄清,真空干燥5 h,所得纳米铁粉中铁元素的质量分数为95.75%。     

A new cleaning facility for particle-free UHV-components

A new cleaning facility has been installed at Deutsches Elektronen-Synchrotron DESY in Hamburg to prepare UHV components hydrocarbon and particle free. Both requirements are important for accelerators using superconducting accelerating structures with high gradients as well as for optical components like mirrors used for the transport of intense photon beams in synchrotron radiation beamlines.The goal of this facility is to combine standard cleaning techniques with latest clean room technology in a manageable way. Thus the new cleaning facility is installed in a clean room which fulfils class 10,000 and in its central part class 100 specifications.¹ The cleaning process following the standard UHV cleaning steps consists of a fine degreasing of the components in an ultrasonic bath. For rinsing ultra pure water² is used. Finally the components are dried using up to 110°C hot filtered air (according to clean room class 100 requirements). Comparable cleaning results for small components are achieved using a dishwasher, which is loaded from outside the clean room. Vacuum chambers of up to 4.8 m length can be treated.A small preassembly area equipped with an oil free pumping station for leak detection and residual gas analysis completes the facility.     

Metallization of polytetrafluoroethylene substrates by ion plating

The paper deals with the adhesion of copper films deposited using the ion plating technique onto polytetrafluoroethylene (PTFE) substrates. The substrates were biased by an r.f. voltage; copper was evaporated by electron bombardment. The results showed that careful sputter cleaning in an argon-oxygen (or helium- oxygen) mixture is essential to achieve good adhesion.Diagnostics by IR spectroscopy indicated that sputter cleaning in pure argon induced some damage at the substrate surface and that PTFE chains were broken. Microscopic inspection gave evidence that sputter cleaning in an argon-oxygen mixture increased the roughness of the substrate surface. Results of adhesion strength measurements for silver films on PTFE substrates after reactive sputter cleaning are presented and discussed. The formation of CuOCbonds at the interface is assumed to play an essential role.     

Storage and utilization patterns of cleaning products in the home: toxicity implications

BACKGROUND AND AIMS: Cleaning products are used to achieve cleaner homes. However, they have been responsible for a considerable number of poisoning cases. The aims of this study were to investigate the storage and utilization patterns of cleaning products in the home, as well as the risk of adverse and toxic effects produced by them. METHODS: This study has been performed using a questionnaire that was developed by the Poison Control and Drug Information Center (PCDIC). The questionnaire was distributed randomly in northern Palestine. The questionnaire included questions regarding storage, utilization habits, and the adverse effects experienced by respondents upon handling the cleaning products. RESULTS: All respondents utilized and stored cleaning products in their homes. Chlorine bleach and acidic cleaning products were the most common. Respondents stored cleaning products at different places in their homes, but most of those storage places were suboptimal and were within the reach of children. The daily utilization rate of cleaning products was 1.6+/-0.8 with chlorine bleach being the most commonly used. Of the respondents, 27% reported experiencing a wide range of acute adverse and toxic effects resulting from cleaning product use and that exposure occurred mainly via inhalation. Caustic substances, bleach, and kerosene were the agents mainly involved in producing these adverse and toxic effects. About half of those who experienced adverse and toxic effects sought medical help, and 22% of them were children younger than 6 years of age. Finally, most respondents reported mixing and discarding cleaning product leftovers and their containers improperly. CONCLUSION AND RECOMMENDATIONS: Correct utilization and safer storage of cleaning products is encouraged. Several preventive strategies should be implemented in order to decrease the incidence of accidental harmful exposure that is due to cleaning agents. The role of the PCDIC is very important in the education, prevention, and management of cleaning product-induced adverse effects.     

超声强化超临界二氧化碳除锈除油污

结合超声清洗的优势与超临界二氧化碳的特性,设计出超声强化超临界二氧化碳复合清洗实验平台,超声换能器最大发射声功率为1 200 W,换能器每工作10 s停止20 s,即一个工作周期为30 s。利用实验平台开展了CD03钢片表面除锈实验,使用ZEISSMerlin高分辨率热场发射扫描电镜对CD03钢片表面进行扫描电子显微镜(Scanning Electronic Microscopy, SEM)和能谱(Energy Dispersive Spectrometer, EDS)分析,实验结果表明,随着清洗时间的延长,铁锈在超声作用下逐渐剥落,超声作用适当的工作周期数后,清洗效果达到最佳,超声作用时间太长会造成对钢片基体的损伤。利用实验平台开展了碳钢片表面油污清除实验,使用徕卡光学显微镜对清洗后的碳钢片做表面形貌观察,利用JA2003电子天平等手段对清洗效果进行了计算分析,同样,超声强化超临界二氧化碳油污清洗也存在一个最佳清洗时间。但是,不同污染所需的最佳清洗时间不同,甚至可以相差很大。在实际的清洗中要先根据污染物的类别确定最佳清洗时间,然后进行清洗。     

Fatigue strength improvement of longitudinal fillet welded out-of-plane gusset joints using air blast cleaning treatment

Blast cleaning treatments are used widely in newly built steel structures to clean forged surfaces and increase the adhesive properties of subsequent coatings. On the other hand, the beneficial effects of a blast cleaning treatment, which are similar to shot peening, on the fatigue strength of welded steel structures are not considered in the fatigue design procedure. In this study, fatigue tests were carried out on as-welded and blast-treated longitudinal fillet welded out-of-plane gusset joints subjected to three different cyclic loading conditions: uniaxial tension, out-of-plane bending and in-plane bending stress cycles. The effect of the blast cleaning treatment on the fatigue strength of the gusset joints was studied. The fatigue tests showed that the blast cleaning treatment increased the fatigue strength of the gusset welded joints, particularly at the lower stress range. A 19% increase in fatigue strength at 2 million cycles and 66% increase in fatigue limit could be realized using the blast cleaning treatment.