DOWNLOAD PDF MICROPOROUS AND AQUEOUS FILTRATION SYSTEMS, INCLUDING WATER TECHNOLOGY GUIDE

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1 Chapter 1 : Microfiltration - Wikipedia Carbon absorption is a widely used method of home water filter treatment because of its ability to improve water by removing disagreeable tastes and odors, including objectionable chlorine. Mesh characteristics Raw materials GVS open mesh fabrics offer you the greatest design flexibility. Raw materials used for the monofilament are polyamide PA6. Mesh opening This is the size micron of any window or opening. The openings are tested by electronic analysis image systems during production. This is also tested by electronic analysis image systems during production. Thread diameter This is the diameter micron of the filament. It is also tested by electronic analysis image systems during production. For instance, in a tubular filter, the frame socket, two ribs and top cover made by plastics should be eliminated from the calculations of the device EFA. In mesh filters you should only eliminate the seal area. Micron Retention The diameter of the largest round particles which can pass through a filter. Since absolute Micron Retention can change during filtration, aperture size can be determined by Bubble Point and Glass Bead Tests methods. Bubble Point Test The pressure required to force air bubbles through a wetted mesh. These tests are typically performed with water; however, test can be conducted on mesh using test liquids other than water. The BP is an indication of the pore size. The average size can then be calculated by taking into account surface tension, liquid density, temperature and immersion depth. Glass Bead Test A mixture containing glass beads is passed through the mesh, the diameter of the largest bead passing through is considered as the absolute micron retention. Filter Efficiency FE This is the quantity of particulate retained compared to the total quantity of particulate to which the filter is challenged. The filter efficiency is determined by a pass test which allows the measurement of the percentage of particles which are removed by the filter. It is expressed by a beta rating representing the effectiveness of the filter that can be calculated as follows: Nonwoven fabric Filtration media Excellent barrier properties to protect your parts from liquids and dust Nonwovens are typically manufactured by putting fibers together in the form of a sheet or web, and then binding them either mechanically, with an adhesive or thermally. They have a porous structure throughout the cross-section and are able to remove particulate from liquid or gaseous streams. Typically, nonwoven filtration media are characterized by pores in the range from 1 to micron, by high dirt holding capacity, high flow rates, and low pressure drop. Nonwoven fabrics are manufactured from many grades of cellulose and most natural and synthetic fibers such as polyester, polypropylene, acrylics, fluoropolymers, polyamide and glass. In the 1 to 20 micron mean flow pore range, the cost of nonwovens are much less than membranes and the dirt holding capacity is generally far superior. Typical GVS applications include fuel, oil, and air filtration. Advantages of nonwoven fabrics include their versatility, diverse functionality, and low price-performance ratio. Many filtration and separation applications require stiffness, minimal flex, and rigidity or even low stretch. Therefore, it is evident that filter design engineers make their media selections based on performance trade-offs. This is routinely studied at GVS. Fiber diameters are controllable and measured in microns. Recently nanotechnology permits the preparation of sub-micron diameter polymeric fibers. Wet-laid filtration media are very regular and are characterized by narrow pore size distribution. Spunbond fabrics serve in applications needing a nominal pore size above 5 micron. They are not as regular as wet laid materials. Meltblown nonwovens have extremely fine fiber diameters, but are not strong fabrics. They are formed by fibers in the micron diameter size range and are character- ized by lower pore size even micron. Test methods evaluation for nonwoven media Standard Test Dust Natural Arizona ground mineral test dusts are available in the following grades: Beta Ratio Ratio of particles present upstream to particles present downstream the filter. Dead end filtration The stream to be filtered flows perpendicularly through the filtration media. Depth Filtration The filter captures contaminants on the surface and into the cross-section the porous part of the filter media. Filter Efficiency Is the percentage of particles of a specific size retained by a filter. It is expressed as the amount of standard test dust required to increase the pressure drop of the filter to a predetermined level, at least 3 times of its initial pressure drop. Page 1

2 Flow Rate The quantity of liquid or gas which flows through the filter at a given temperature and pressure. Frazier Permeability It is the air flow in CFM which passes through one square foot of filtration medium at 0. Gurley Permeability It is the time required for a fixed volume of air to pass though a filter medium placed within a specific apparatus HEPA An air filter or filtration medium which can reject The dust not retained by the filter is recycled to the main tank. Single-pass system Standard test dust is prepared in slurry form, mixed with the testing fluid in the system main tank and circulated through the test filter. The dust not retained by the filter is not recycled to the main tank. Tangential Crossflow Filtration The stream to be filtered flows tangentially to the filtration media, part is filtrated and part is recycled. Polymeric membrane filtration Filtration through a membrane allows for continuous exchange of gases and vapors, providing pressure equalization within the auto parts enclosures that are often exposed to rapid temperature fluctuations, caus- ing extreme changes in internal pressure and creating a vacuum that puts stress on the seals. Small pore size reduces liquid penetration speed through the filter due to slow airflow, while larger pore size lets liquids pass through faster and easily reduces retention performance. Oleophobic membranes are post-treated to repel low surface tension fluids such as oils and alcohols. Key properties and pore size ranging from 0. Membrane Specifications Pore size Pore size is determined by the size of the particle that is expected to be retained with a defined degree of efficiency. Retention capacity Retention efficiency is also dependant on such process conditions as concentration, operating pressure etc. Rating parameters can vary among manufacturers. Chemical compatibility This is the ability of the membrane to resist to chemicals without mechanical or chemical damage from chemical exposure. Information about the liquid used with a specific filter material should be outlined before application to determine compatibility, GVS can assist customers in choosing the proper filter and housing materials. Extractables Extractables are contaminants typically chemicals that elute from the filter which might affect qual- ity of the effluent. Binding This is the property of substances to be filtered having affinity with membranes. Particularly it could lead to loss of active components of the liquid to be filtered reducing its beneficial effect. Air Flow AF It is the amount of air that passes through a fixed surface of membrane with a specific applied pressure. Filter Efficiency FE Quantity of particulate retained compared to the total quantity of particulate to which the filter is chal- lenged. For instance, whereas a 25 mm device may start out with a disc of filter media that is cut to 25 mm, the sealing surfaces should be eliminated from the calculations of the device EFA. Contact Angle Measurement The measure of the angle between a drop of liquid and a surface of a solid is used to determine the surface hydrophobicities or oleophobicities of membranes and to assess their separation potential. Polymers for injection The automotive industry is the largest consumer of plastic materials since their properties meet require- ments for a large variety of automotive applications. They are widely used in original equipment and after-market sectors. Usually, thermoplastic polymers are supplied in the form of pellets, which often contain additives to enhance processing or to provide necessary characteristics in the finished product e. The temperature service range of thermoplastics is limited by their loss of physical strength and eventual melting at elevated temperatures. Main Thermoplastic resin used in Automotive Applications Nylon Polyamide - comprises the largest family of engineering plastics with a very wide range of applications. Typically Nylon - especially if glass fiber reinforced - can replace metal in many applica- tions due to its good resistance to wear and abrasion, good mechanical properties even at elevated temperatures, low permeability to gases and good chemical resistance. GVS typically uses PA for powertrain applications such as fuel injector, fuel pumps filters and filters in transmission applications. Page 2

3 Chapter 2 : Micropore Filters, Micropore Filters Suppliers and Manufacturers at blog.quintoapp.com blog.quintoapp.comorous and Aqueous Filtration Systems, Including Water Technology GuidePrecision Assembly Technologies for Mini and Micro Products: Proceedings of the IFIP TC5 WG Third International. Introduction This document is designed as a guide for household water treatment, not a recommendation. Filtration Filtration is a physical process that occurs when liquids, gases, dissolved or suspended matter adhere to the surface of, or in the pores of, an absorbent medium. Filtration of contaminants depends highly on the amount of contaminant, size of the contaminant particle, and the charge of the contaminant particle. Microfiltration A microfiltration filter has a pore size of approximately 0. Ultrafiltration An ultrafiltration filter has a pore size of approximately 0. Ultrafiltration filters remove particles based on size, weight, and charge; Ultrafiltration has a very high effectiveness in removing protozoa for example, Cryptosporidium, Giardia ; Ultrafiltration has a very high effectiveness in removing bacteria for example, Campylobacter, Salmonella, Shigella, E. Nanofiltration A nanofiltration filter has a pore size of approximately 0. Top of Page Reverse Osmosis Systems Reverse Osmosis Systems use a process that reverses the flow of water in a natural process of osmosis so that water passes from a more concentrated solution to a more dilute solution through a semi-permeable membrane. Pre- and post-filters are often incorporated along with the reverse osmosis membrane itself. A reverse osmosis filter has a pore size of approximately 0. Reverse Osmosis Systems have a very high effectiveness in removing protozoa for example, Cryptosporidium, Giardia ; Reverse Osmosis Systems have a very high effectiveness in removing bacteria for example, Campylobacter, Salmonella, Shigella, E. Top of Page Distillation Systems Distillation Systems use a process of heating water to the boiling point and then collecting the water vapor as it condenses, leaving many of the contaminants behind. Distillation Systems have a very high effectiveness in removing protozoa for example, Cryptosporidium, Giardia ; Distillation Systems have a very high effectiveness in removing bacteria for example, Campylobacter, Salmonella, Shigella, E. Top of Page Ultraviolet Treatment Systems with pre-filtration Ultraviolet Treatment with pre-filtration is a treatment process that uses ultraviolet light to disinfect water or reduce the amount of bacteria present. Ultraviolet Treatment Systems have a very high effectiveness in removing protozoa for example, Cryptosporidium, Giardia ; Ultraviolet Treatment Systems have a very high effectiveness in removing bacteria for example, Campylobacter, Salmonella, Shigella, E. Water Softeners Water Softeners use ion exchange technology for chemical or ion removal to reduce the amount of hardness calcium, magnesium in the water; they can also be designed to remove iron and manganese, heavy metals, some radioactivity, nitrates, arsenic, chromium, selenium, and sulfate. They do not protect against protozoa, bacteria, and viruses. Top of Page Please remember that: Point of Use POU water treatment systems typically treat water in batches and deliver water to a single tap, such as a kitchen sink faucet or an auxiliary faucet. Point of Entry POE water treatment systems typically treat most of the water entering a residence. Point of entry systems, or whole-house systems, are usually installed after the water meter. The treatment technologies described can be used in conjunction with each other for greater pathogen reduction. The addition of coagulants, carbon, alum, and iron salts to filtration systems may aid in chemical removal from water. Hygiene In addition to providing safe drinking water to your household, you can also protect yourself and others from waterborne illness by paying practicing good personal hygiene: Wash hands before preparing and eating food, after going to the bathroom, after changing diapers, and before and after tending to someone who is sick. Clean Hands Save Lives website. Page 3

4 Chapter 3 : Membranes, all manufacturers in Japan in blog.quintoapp.com Anna W. Crull is the author of Electric Vehicle Market ( avg rating, 0 ratings, 0 reviews, published ), Structural And Specialty Adhesives ( av Home My Books. General principles[ edit ] Microfiltration usually serves as a pre-treatment for other separation processes such as ultrafiltration, and a post-treatment for granular media filtration. The typical particle size used for microfiltration ranges from about 0. There are also two pump configurations, either pressure driven or vacuum. A differential or regular pressure gauge is commonly attached to measure the pressure drop between the outlet and inlet streams. See Figure 1 for a general setup. Overall setup for a microfiltration system The most abundant use of microfiltration membranes are in the water, beverage and bio-processing industries see below. Water treatment Perhaps the most prominent use of microfiltration membranes pertains to the treatment of potable water supplies. The membranes are a key step in the primary disinfection of the uptake water stream. Such a stream might contain pathogens such as the protozoa Cryptosporidium and Giardia lamblia which are responsible for numerous disease outbreaks. Both species show a gradual resistance to traditional disinfectants i. In that sense, both filtration and disinfection take place in a single step, negating the extra cost of chemical dosage and the corresponding equipment needed for handling and storage. Similarly, the MF membranes are used in secondary wastewater effluents to remove turbidity but also to provide treatment for disinfection. At this stage, coagulants iron or aluminum may potentially be added to precipitate species such as phosphorus and arsenic which would otherwise have been soluble. Sterilization microbiology Another crucial application of MF membranes lies in the cold sterilisation of beverages and pharmaceuticals. Similarly, pharmaceuticals have been shown to lose their effectiveness upon heat addition. Petroleum refining processes Furthermore, microfiltration membranes are finding increasing use in areas such as petroleum refining, [9] in which the removal of particulates from flue gases is of particular concern. In addition the modules must have a low fouling profile and most importantly, be available at a low-cost for the system to be financially viable. Dairy Aside from the above applications, MF membranes have found dynamic use in major areas within the dairy industry, particularly for milk and whey processing. The MF membranes aid in the removal of bacteria and the associated spores from milk, by rejecting the harmful species from passing through. This is also a precursor for pasteurisation, allowing for an extended shelf-life of the product. However, the most promising technique for MF membranes in this field pertains to the separation of casein from whey proteins i. Other applications[ edit ] Other common applications utilising microfiltration as a major separation process include Clarification and purification of cell broths where macromolecules are to be separated from other large molecules, proteins, or cell debris. The microfiltration process is pressure driven with suspended particles and water as retentate and dissolved solutes plus water as permeate. The use of hydraulic pressure accelerates the separation process by increasing the flow rate flux of the liquid stream but does not affect the chemical composition of the species in the retentate and product streams. Fouling describes the deposition and accumulation of feed components such as suspended particles, impermeable dissolved solutes or even permeable solutes, on the membrane surface and or within the pores of the membrane. Fouling of the membrane during the filtration processes decreases the flux and thus overall efficiency of the operation. This is indicated when the pressure drop increases to a certain point. It occurs even when operating parameters are constant pressure, flow rate, temperature and concentration Fouling is mostly irreversible although a portion of the fouling layer can be reversed by cleaning for short periods of time. Cross flow filtration is understood to be a unit operation rather than a process. Refer to Figure 2 for a general schematic for the process. Dead-end filtration ; all of the process fluid flows and all particles larger than the pore sizes of the membrane are stopped at its surface. All of the feed water is treated at once subject to cake formation. Figures 2 and 3 are missing from the article Process and equipment design[ edit ] The major issues that influence the selection of the membrane include [19] Capacity and demand of the facility. Percentage recovery and Page 4

5 rejection. Quality of the fluid to be treated Pre-treatment processes. Chapter 4 : Results for Anna-Crull Book Depository Microporous and aqueous filtration systems, including water technology guide by Anna W. Crull 1 edition - first published in Chemicals for enhanced oil recovery. Chapter 5 : technology Osmosis Water Softeners use ion exchange technology for chemical or ion removal to reduce the amount of hardness (calcium, magnesium) in the water; they can also be designed to remove iron and manganese, heavy metals, some radioactivity, nitrates, arsenic, chromium, selenium, and sulfate. Chapter 6 : Drinking Water Filtration For the first time, users and specifiers of water filtration technology will be able to select from the most comprehensive range of self-cleaning filter systems available in the UK ranging from Chapter 7 : Anna W. Crull (Author of Electric Vehicle Market) Membrane distillation is an innovative membrane-based process with promising applications such as water desalination, treatment of industrial effluents, the pharmaceutical and food industries, and the removal of organic compounds from aqueous streams. Chapter 8 : Anna W. Crull Open Library Pharmaceutical Pure Water Guide. of water purification components including storage tanks and the Microporous depth filters. Chapter 9 : Microporous membranes from polyolefin-polyamide blend materials 2 Ultrafree-CL Centrifugal Filter Units Membrane Types and Applications Ultrafree-CL units are available with ultrafilters and microporous filters. Page 5