刚性高分子精密微孔过滤技术及其应用

高分子精密微孔过滤技术由硬件 (微孔过滤管与精密微孔过滤机 )与软件 (计算 ,设计与应用技术等 )两大部分组成。微孔过滤管 (微孔ＰＥ管与微孔ＰＡ管 )与精密微孔过滤机已形成系列化产品 ,浙江省温州市微孔过滤公司 (原温州市东瓯水处理器材厂 )已连续专业生产 2 0多年。商品注册商标为“东瓯牌”。微孔过滤管 (包括微孔过滤板 )有各种尺寸 ,每种尺寸有 9种微孔孔径规格 (微孔孔径从 1～ 12 0 μｍ)。已开发出ＰＧＫ、ＰＧＨ、ＰＧＲ、ＰＧＷ、ＰＧＰ、ＰＧＸ、ＰＧＣ与ＰＧＢ等不同结构型号精密微孔过滤机 ,每种型号有不同过滤面积 ,小至 …     

高分子精密微孔过滤技术及其在石化生产中的应用

被国家科委选为“八五”与“九五”期间“国家级科学技术成果重点推广项目”的高分子精密微孔过滤技术在我国工业生产已推广18年，对微米级与0.5μm以上的亚微米级微粒具有很高的过滤效率，应用面很广。在石化工业生产也有很多成功应用的实例。1高分子烧结微孔过滤技术高分子烧结精密微孔过滤技术由高分子精密微孔过滤机，辅助装置及应用技术等硬件技术与软件技术组成。高分子精密微孔过滤机是该技术的核心。它由刚性的高分子烧结微孔过滤管与具有气动快开排渣大底盖的机体结构两部分组成。辅助装置主要是输送料液的泵，吹干、排渣与微孔管…     

连续化静电纺尼龙6/改性聚乳酸复合膜的制备及性能

以聚乳酸无纺布(PLA)为基材,通过3-氨丙基三乙氧基硅烷(KH550)对PLA进行改性(mPLA),并采用连续化电极丝静电纺丝法在mPLA表面制备尼龙6(PA6)纳米纤维膜得到了mPLA/PA6复合膜。使用红外光谱(FTIR)、X射线衍射仪(XRD)和扫描电镜(SEM)表征mPLA/PA6的化学结构、结晶行为和微观形貌,并对其空气过滤性能、疏水性能和降解性能进行了研究。结果表明,KH550修饰在PLA纤维上,将复合膜由亲水转变为疏水,水接触角为131°。当纺丝电压为80 kV,收卷速度为0.2 m/min时,复合膜的平均直径为58 nm,对直径≤0.3μm的细颗粒物(PM0.3)的过滤效率为99.9%,过滤阻力为118.7 Pa;此时产量为14.4 m²/h;且在17.5 W/m²紫外辐照强度下4 d降解率为99%,为工业连续化制备可降解空气过滤材料探索了有益的途径。     

提高小苏打质量的试验研究——微孔蛇纹石管在精密过滤上的应用

本文是提高小苏打质量的研究总结,其重点部分是采用微孔蛇纹石管的过滤试验。碳酸钠溶液中不溶物的分散度大且含量低。在过滤工艺中代表一种物料类型。微孔管过滤适用这类物料,达到精密过滤目的,报告中提供了具体方法。扩大了微孔蛇纹石管的使用范围,也说明了它的优点。     

PS接枝PA6共聚合研究

采用熔融接枝法制备PA6-g-PS共聚物,研究了原料配比(PA6：PS)、引发剂用量(DCP％)和反应温度(T)对接枝效率的影响。结果表明：产物PA6-g-Ps的接枝效率随DCP%的增加及T的升高,均呈现先上升后下降的趋势;而随PA6：PS的增加则一直呈下降趋势。同时,对PA6-g-Ps接枝共聚产物进行FITR、X-射线衍射分析。     

微孔精密过滤技术在盐水二次过滤中的应用

微孔精密过滤机过滤的核心元件———高分子ＰＥ微孔管，孔径是关键工艺，孔径的大小关系到盐水二次过滤的质量与流量。防止微孔管堵塞，需预涂敷过滤助剂，过滤效果稳定，经济效益明显。     

微孔管过滤技术在合成氨装置中的应用

1　过滤原理及特点近年来 ,我国成功开发了针对液、固相或气、固相为工作介质的、有超细物分离要求的微孔管式过滤技术。该技术已广泛应用于化工 (如催化剂、洗涤剂的过滤与洗涤 ,化工废物的回收处理 )、化肥 (如脱碳液、铜氨液的过滤 )、医药(如生物发酵液的过滤与洗涤 ,粉末活性炭的精密过滤 )、食品 (如酒、食糖的澄清过滤 )、轻工(如食用油的澄清过滤 ,矿泉水、纯净水的反渗透前精密过滤 )等行业[1～ 7] ,其过滤原理及特点大致相同。1 .1　微孔管过滤的基本原理微孔管式过滤技术原理见图 1。其关键元件称作微孔管 ,它是一种特殊塑料管 ,…     

刚性高分子微孔过滤在脱碳液过滤改造中的应用

以刚性高分子微孔管作为过滤介质的精密过滤 ,具有过滤效率高、可反吹再生、操作简单、耐腐蚀、使用寿命长等特点。它从微孔过滤介质、过滤机结构、精密过滤计算方法等方面改革了传统的精密过滤作业。采用该技术改造合成氨净化系统的脱碳液过滤 ,取得了良好的使用效果和经济效益。     

刚性高分子粗密微孔过滤技术及其应用

高分子精密微孔过滤技术由硬件(微孔过滤管与精密微孔过滤机)与软件(计算,设计与应用技术等)两大部分组成.     

尾管过滤式水力旋流器滤出效率实验研究

将过滤用微孔管与常规液-液水力旋流器相结合,在后者的结构基础上研制了一种改进结构的尾管过滤式水力旋流器,并利用该旋流器对油水混合液进行了分离实验研究,测定和分析了尾管段滤出效率和底流效率。     

Electrospinning of polyamides with different chain compositions for filtration application

Electrospinning of several polyamides, PA6, PA66, PA612, PA614, PA1012, and PA1014, having different chain compositions and lengths of diacid and diamine segments, was demonstrated. Electrospinnability and fiber production rate of these polyamides were evaluated. Electrospun fibers were characterized with regard to their use in air filtration by measuring fiber diameter and filtration efficiency of fiber coating. Longer nonpolar chain segments of higher polyamides could in theory indicate higher dielectricity compared to PA6 and PA66, which would be an advantage in filtration applications. The solubility in polar formic acid and electrospinnability of higher polyamides, on the other hand, were clearly impaired with increased length of chain segments. Hence, PA66 is our best choice, and PA612 and PA6 our second options for commercial filtration applications if fiber electrospinnability, production rate, fiber diameter, and its distribution are concerned. Filtration efficiency of more than 95% of the particles having a diameter of 0.16 μm and above was achieved with 0.5 g/m² coating of PA66 nanofibers. Further increase in coating weight mainly increased the pressure drop to an unusable range without a significant further improvement of filtration efficiency. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers.     

空气滤清器过滤阻力多元关联式的研究

为减低空气滤清器过滤阻力,对空气滤清器流场特性进行的实验测试和模拟计算,旨在于为空气滤清器的优化设计提供相关的理论指导和依据。采用CFD模拟技术,结合实验测试的方法,建立了空气滤清器的CFD模拟的两维和三维模拟模型,计算机模拟计算结果与实验测试结果吻合,计算得出空气滤清器的过滤阻力与其各自影响因素的变化规律,通过数值模拟计算结果的回归分析,给出了空气滤清器总成过滤阻力与其显著影响因素的单因素关联式。利用大量的过滤压降与不同滤清器结构参数、过滤速度和过滤介质特性参数的模拟数据,回归得出总成过滤阻力与入口速度、滤芯褶数、进气管长、进气管径、出气管长、出气管径和滤纸厚度的无量纲的多元关联式。     

Multilevel‐layer‐structured polyamide 6/poly(trimethylene terephthalate) nanofibrous membranes for low‐pressure air filtration

Multilevel‐layer‐structured polyamide 6 (PA6) and poly(trimethylene terephthalate) (PTT) nanofibrous membranes were fabricated by an electrospinning method. The morphology of the multileveled layers membranes were characterized by scanning electron microscopy. The tensile strength of the PA6–PTT membranes were controlled by the regulation of the layer structure. Additionally, the surface area of the multilevel‐layer‐structured membranes was also investigated with the nitrogen physisorption isotherms. Furthermore, the multilevel‐layered membranes, with a tensile strength of 9.8 MPa and a surface area of 5.1601 m²/g on 300‐nm dioctylphthalate (DOP) aerosol particles, showed a higher efficiency (95.825%) and a lower pressure drop (55 Pa) than the pure PA6 membranes (with values of 94.634% and 467 Pa, respectively). This suggested a new method for high‐efficiency and low‐pressure‐drop filtration applications. Correlations between the filtration pressure drop and filtration efficiency with the structure of the membranes, particle size, and surface velocity were proposed, and the advantage of the multilevel‐layered structure is also discussed. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44716.     

Aerosol filtration performance of nanofibrous mats produced via electrically assisted industrial-scale solution blowing

Highly efficient polyamide 6 (PA6)-based nanofibrous air filter media was developed for particulate matter (PM) removal in the ambient atmosphere. The PA6 nanofibrous mats exhibited 85% PM0.3 capture performance at a cost of 164 Pa pressure drop when the multiple-nozzle solution blowing system was set to 8 m/h fabric winding speed. However, an increase in the winding speed at a constant feeding rate lowered the filtration efficiency to 62% due to the less amount of nanofibrous mats collected on the substrate. The application of electrical field at the same parameters allowed us to produce a filter media having FFP3-level filtration performance, which means 99% PM0.3 capture performance. This was attributed to a fine fiber diameter (116 nm), higher solidity value (0.149), and lower average pore size (2.28 μm). These results show that the electrically assisted solution blowing provides a feasible route for the production of high-quality nanofibrous filter media.     

Physical filtration efficiency analysis of a polyaniline hybrid composite filter with graphite oxide for particulate matter 2.5

Particulate matter (PM) 2.5 pollution is a prevalent environmental and public health issue that has raised serious global concerns. Because standard heating, ventilation, and air conditioning filters are incapable of filtering out PM 2.5 particles efficiently, different methods of PM 2.5 filtration, such as physical filtration and electrostatic filtration, are under investigation to develop a filter with a high filtration efficiency and a low pressure drop. According to various studies, pressure drop has a significant influence on the filtration efficiency. An equation for the theoretical trend was generated based on the composite data gathered from similar filtration studies and was used to evaluate the relationship between pressure drop and filtration efficiency. Here, the theoretical equation indicated that the filtration efficiency increased as the pressure drop on a filter increased until 0.01 psi where the efficiency remained near constant at approximately 99.9%. In this study, we introduce a graphite oxide (GO) and polyaniline (PANi) composite hybrid filter in order to create a low-pressure (1.2 psi) drop filter. By adding GO flakes to the PANi matrix, we not only produced a highly permeable filter while allowing continuous gas flow, but also achieved a remarkable and highly effective PM 2.5 filter with a filtration efficiency of 99.7 ± 0.08%.     

高湿黏性颗粒在聚四氟乙烯微孔膜滤料表面沉积特性的数值模拟

基于聚四氟乙烯(PTFE)微孔膜滤料扫描电镜(SEM)图像,建立PTFE微孔膜滤料微观结构模型,采用计算流体力学和离散单元法(CFD?DEM)耦合的方法对黏性颗粒在微孔膜滤料表面沉积特性进行模拟,引入液桥力模型,忽略范德华力的作用,统计计算域内颗粒的受力情况,分析了不同表面能条件下3~6 ?m粒径颗粒在微孔膜滤料表面的沉积特性,将模拟结果与黏附效率的经验公式进行对比。结果表明,黏附效率与经验值、颗粒受力与液桥力模型的相对误差均在6%以内,CFD?DEM耦合计算方法可用于模拟不同环境湿度条件下的颗粒沉积;过滤风速、粒径与黏性是影响沉积形态的重要因素,提高过滤风速及增大颗粒粒径与黏性,颗粒更易在滤料表面形成稳定的树突结构,黏附效率及含尘压降增加。环境相对湿度影响两物体间液桥体积,接触力影响颗粒沉积,当增加表面能与液桥体积时,接触力及液桥力均相应增加,根据受力平衡原理,环境相对湿度对颗粒沉积影响很大。     

Relation of Structure,Properties and Performance of Fibrous Media for Gas Filtration

The relation between the structure, permeability and filtration performance of needled nonwoven filter media is reported. Surface treated and untreated fabrics were studied, including microporous coated, laminated e‐PTFE, heated calendered and surface singed materials. Surface treatments appear to impart higher packing densities, but mean pore size is governed by the type of treatment with microporous and PTFE having the smaller values. Filtration performance was determined from graphs of pressure drop with filtration duration, differences in filtration efficiencies and the dust concentrations in gas emissions. Except for the singed materials, the treated fabrics depicted surface filtration and the untreated depth filtration. The trend for singed fabrics showed initial depth followed by surface filtration. Markedly higher filtration efficiencies were obtained with surface filtration, which corresponded with higher rates of pressure drop. Surface treatments, giving smaller mean pore sizes, resulted in higher filter cake resistance owing to low particle penetration through the base fabric.     

天然气用聚结过滤元件性能的测定与分析

为了评价目前天然气净化用滤芯气液分离性能,利用聚结型滤芯气液过滤性能的检测装置研究了滤芯的放置方式、滤芯的有效厚度及填充密度等相关因素对气液过滤性能的影响。结果表明：在相同条件下,滤芯垂直于地面放置比水平位置放置时排液较顺畅,气液过滤效果较好,并且压降至少降低25%;不同材质滤芯,随着滤芯厚度在6~32mm范围内增加,滤芯稳态压降增加,过滤器出口液滴浓度减小,过滤性能提高;滤芯的填充密度增加,滤芯压降增大,过滤器出口液滴浓度减小。     

Air flows and pressure drop modelling for different pleated industrial filters

A dimensionless model was developed to determine the pressure drop across clean pleated filters, according to filter medium type, geometric characteristics of the pleating (distance between two pleats, pleat height, etc) and air flow parameters (filtration velocity, air density, etc). The model was derived from both experimental and numerical results obtained from nuclear and automotive filters — high efficiency particulate air (HEPA) and low efficiency particulate (LE), respectively. The major findings were that a more homogeneous air flow distribution occured over the surface of the pleated HEPA filter, while geometric characteristics had a greater influence on the initial pressure drop across the LE filter. The numerical model highlighted the fundamental importance of the filter medium's air flow resistance on air flow distribution.     

孔径梯度分布对亲油型滤材气液过滤性能的影响

在天然气净化、大型旋转机械曲轴箱通风和压缩空气过滤等领域,气液聚结过滤器具有广泛的应用。利用滤材过滤性能实验装置,分析了气液过滤过程中不同孔径梯度分布的亲油型滤材的压降、穿透率和饱和度变化,比较了其过滤性能、内部液体分布特性以及对液滴二次夹带现象的影响。结果表明：在气液过滤过程“通道压降”阶段,孔径递增滤材压降和0.8 μm以上液滴穿透率的变化曲线具有明显的分层特征。不同孔径梯度分布滤材的稳态过滤性能存在明显差异,主要原因是滤材内部存在液体运移通道的传递现象。通过与孔径递减和孔径均匀分布滤材的稳态过滤性能对比,发现孔径递增滤材在保证较低压降的同时具有最高的品质因子,有利于减少液滴二次夹带现象的发生,且对0.8 μm以上不同粒径液滴均具有最高的过滤效率,即孔径递增滤材在气液聚结过滤器设计中更具优势。