Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

3. filtration textiles

6,808 views

Published on

filtration textiles

Published in: Engineering
  • www.HelpWriting.net is a really good site. thanks
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
  • Don't forget another good way of simplifying your writing is using external resources (such as ⇒ www.HelpWriting.net ⇐ ). This will definitely make your life more easier
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
  • Hello! I have searched hard to find a reliable and best research paper writing service and finally i got a good option for my needs as ⇒ www.WritePaper.info ⇐
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
  • NEW Gender Study: 74% OF Men Are More Attracted To Women Who Do This One Thing. Read MORE.. =>> https://dwz1.cc/YhTuPiiH
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
  • I know that while making the choice to recover was crucial, and having the will comes in handy, but it is the girls in this program and their support that has helped me make it this far. I have been in recovery without purging for two months. I know I still have a long way to go, but I could not imagine doing it on my own. Even in this short amount of time, I can see myself emerging and the world is opening up before me. I have started making plans to do the things I’ve wanted to do for years, but that got lost in my bulimia cycle. Just taking that first step in recovery, has made me see what is really important. ●●● http://ishbv.com/bulimiarec/pdf
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here

3. filtration textiles

  1. 1. Textiles in Filtration By: Granch Berhe 2015
  2. 2. Introduction to Filtration • Picking out • Decanting • Evaporation • Dissolution • Filtration etc … Separation of particles, molecules, atoms and ions from one another may be performed by: Filtration is one type of separation
  3. 3. Filtration Filtration is a mechanical or physical operation, which is used for the separation of solids from fluids (liquids or gases) by interposing a medium through which only the fluid can pass. Oversize solids in the fluid are retained, but the separation is not complete; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the pore size and filter thickness). Filtration is used to separate particles and fluid in a suspension, where the fluid can be a liquid, a gas or a supercritical fluid. Depending on the application, either one or both of the components may be isolated.
  4. 4. Particulate Sizes and Filtration RangesParticulate Sizes and Filtration Ranges Ref. : http://www.gewater.com
  5. 5. Principles of filtration • There are five principles of filtration: – Interception – Inertial disposition – Random diffusion – Electrostatic disposition – Gravitational forces
  6. 6. Dust collection principles
  7. 7. Dust collection principles
  8. 8. Filtration and textiles • Both textile fibers and fabric form an important part of filtration. • Filtration fabrics are used widely in: – Vacuum cleaners – Medical uses – Power stations – Petrochemical plants – Sewage disposal – Water filtration – Geotextiles etc.
  9. 9. Applications In vaccum cleaners -The bag used in vaccum cleaners is the typical method to capture the debris vacuumed up. It involves a paper or fabric bag that allows air to pass through, but attempts to trap all dust and debris in the bag. The bag may be disposable, or designed to be cleaned and re-used. In medical uses -Woven filters set the standard for safe and efficient filtration solutions in medical devices. Precision woven fabrics is a critical component for medical filter devices, blood filtration : precision woven fabrics set the standard for safe and efficient filtration.
  10. 10. In Power Stations-A bag house(BH, B/H) or fabric filter (FF) is an air pollution control device that removes particulates out of air or gas released from commercial processes or combustion for electricity generation. In Sewage disposal- a non-woven fabric filter was experimentally evaluated for solid-liquid separation in an activated sludge reactor as an alternative membrane. A polypropylene fabric filter (70, 50 and 35g/m2) was used. Power plants, steel mills, pharmaceutical producers, food manufacturers, chemical producers and other industrial companies often use bag houses to control emission of air pollutants. Bag houses came into wide spread use in the late 1970s after the invention of high-temperature fabrics (for use in the filter media) capable of withstanding temperatures over 350°F
  11. 11. Water filtration-This type of filter is a common solution to the problem of obtaining clean water in many parts of the world, especially rural parts of developing nations. It is a fairly simple process that involves only materials that are available inmost parts of the world In Geo-textiles-The non-woven geo-textile fabric is a common choice for areas looking to stabilize, separate or filter materials. All non- woven fabrics come with a needle-punched exterior that allows thin water particles to filter through the fabric while keeping soil from filtering through. This geo-textile filter fabric helps to retain fine particles when water passes from fine to coarse-grained soil .
  12. 12. Yarn types and fabric constructions The technologist has basically three types of yarn to choose from when designing a filter fabric, namely : 1.monofilament 2.multifilament and 3.staple-fibre Monofilament: The diameters of the monofilaments used range from 0.1mm up to 1.0mm, the smaller diameters being used mainly in applications involving filter presses, pressure leaf and candle filters, rotary vacuum disc and rotary vacuum drum filters, whereas the larger diameters are used mainly in relatively coarse filtration applications involving heavy duty vacuum belt filters or multiroll filter presses. Although normally extruded in round cross- section, for special applications they may also be produced in flat or oval form.
  13. 13. Monofilament fabric, five-end satin weave For most filtration applications involving monofilaments, the majority of diameters used are in the range 0.15–0.35mm, yielding fabric area densities between 180 and 450gm-2. Heavy-duty filter belt applications, on the other hand, usually employ diameters from 0.3–1.0 mm resulting in area densities from 500–1700 gm-2.
  14. 14. Multifilament Fabric area densities in this category vary from as little as 100gm-2 to around 1000 gm-2.
  15. 15. Staple-fibre yarns For this, and filtration purposes in general, the yarns are usually spun with 3.3 decitex fibres in relatively coarse linear densities, typically from 130–250 tex. Fabrics in this category are normally woven in area densities ranging from 350–800 gm-2, the lighter and intermediate fabrics generally being used in pressure leaf and rotary vacuum drum filters and the heavier fabrics in filter presses.
  16. 16. Staple-fibre yarns For this, and filtration purposes in general, the yarns are usually spun with 3.3 decitex fibres in relatively coarse linear densities, typically from 130–250 tex. Fabrics in this category are normally woven in area densities ranging from 350–800 gm-2, the lighter and intermediate fabrics generally being used in pressure leaf and rotary vacuum drum filters and the heavier fabrics in filter presses.
  17. 17. Fabric construction Three basic types of construction are 1.woven fabrics, 2.needle felts and 3.knitted structures. The first two are produced in flat form and will require (i) slitting to appropriate width and (ii) converting into tubular sleeves, whereas knitted fabrics may be produced directly in tubular form.
  18. 18. Important Characteristics of Filter Fabric – With the fabric warp and weft density increases, the filtration resistance of the filter cloth increases gradually. – With the increase in the fabric warp, weft twist, the filtration resistance of the filter cloth is reduced gradually. – Porosity of the fabrics. – Air permeability of the fabrics.
  19. 19. Woven fabrics Used predominantly in shake collectors, this class of filter fabric may comprise twisted continuous filament yarns, short staple-fibre yarns (cotton or woollen spinning system) or perhaps a combination of both. Weave patterns may be in the form of elementary twills, for example 2/1, 2/2 or 3/1, or perhaps simple satin designs, the latter providing greater flexibility and hence superior resistance to flex fatigue and a smoother surface for superior cake release. Woven fabric area densities are typically in the range 200–500gm-2.
  20. 20. Woven fabrics Plain weave-this weave is particularly suitable for flexible yarns of the multifilament and short staple-fibre types. The weave is also ideally suited to applications where thread displacement, due for example to high internal pressures Twill Weave: this facilitates the production of fabrics of higher area density and hence greater bulk, Usually produced in simple 2/2 or 2/1 style. Twill weave fabrics are also marginally more flexible than plain weave fabrics, which may be advantageous when fabricating cloths of complex make up or indeed when fitting the cloths on the filter
  21. 21. Woven fabrics Satin weaves: Both regular and irregular satin weaves are employed. The irregular weaves, such as the four-shaft construction, are frequently found in more densely sett high efficiency fabrics, often with two warp threads being woven as one. From this it will be appreciated that the weaves with the longer floats are normally used in conjunction with monofilament yarns. Link Fabric: link fabrics are produced by a novel technique in which polyester monofilaments are wound into spiral form then meshed with similar monofilaments, which are spiral wound in the opposite direction.
  22. 22. Link fabrics
  23. 23. Needle felts In the majority of cases they are produced by needle punching a batt of fibre – a number of layers of carded fibre web formed by means of a cross-laying . By far the most widespread in dust collection processes, providing an infinitely larger number of pores and facilitating considerably higher filtration velocities than woven fabrics. The majority of needle felts actually fall in the range 400–510 gm-2, these facilitating generally higher filtration velocities. However, in the event that the dust is particularly abrasive, a longer life may be expected from felts in the 540–640gm-2 range.
  24. 24. Finishing treatments These are designed essentially to improve (i)Fabric stability, (ii)Filtration collection efficiency, (iii)Dust release, and (iv)Resistance to damage from moisture and chemical agents. A number of finishing processes are employed to achieve these goals, for example heat setting, singeing, raising, calendaring, ‘special surface treatments’ and chemical treatments. Knitting fabrics It’s being produced in seamless tubular form, weft-knitted fabrics provide, in theory, an attractive and economic alternative to both woven and needled constructions.
  25. 25. Dimensional stability treatments As in the production of fabrics for dust collection applications, heat is again instrumental in inducing the necessary fabric stability, which, on this occasion, may be achieved through: •Hot aqueous treatment, •Heat setting or a combination of both. In the case of aqueous treatments these may also include surfactants to remove unwanted fibre and yarn processing aids. Once again media manufacturers will be aware of the machine speeds and temperatures that will be necessary in these processes to achieve the maximum effect
  26. 26. Surface modifications Surface of a fabric can be significantly enhanced by physical/thermal means such as singeing and calendaring, the development of chemical coatings production of still more efficient filter media. As in dust collection, where surface coatings have been available for many years, the treatments are designed to present a microporous structure to the slurry which effectively restricts the penetration of particles to all but a few micrometres in depth.
  27. 27. Permeability regulation The calendaring operation is able both to modify the surface and also to regulate the fabric’s permeability by means of heat and pressure. Before calendering After calendering
  28. 28. Fabric test procedures These are carried out in normal textile laboratories in order (i) to ensure that the materials under test have been manufactured in accordance with design specification, and (ii) to monitor any short, medium or long term trends. Such tests are concerned primarily with; Area density, Fabric sett (hole), Yarn types and linear densities, Fabric structure, Air permeability, Thickness and density (principally needlefelts), Tensile properties and fabric stability.
  29. 29. Projected World Population Growth http://www.globalchange.umich.edu/globalchange2/current /lectures/human_pop/human_pop.html 1950-ref 2000~2x 2050~3x HealthHealth,, EnvironmentEnvironment andand EnergyEnergy are three major research areas!are three major research areas!
  30. 30. Problem: a Shortage of Clean Water • 41% of the Earth’s population (2.3 billion) live in water- stressed areas; 3.5 billion by 2025. • 1.2 billion people live without clean, piped water (WHO). • Water shortages limit economic development and threaten human life.
  31. 31. U nited statesAsia/Pacific Europe M iddle East/Africa Latin Am erica/Caribbean $0 $200 $400 $600 $800 $1,000 $1,200 $1,400 Sales($millions) NewDesalinationCapacity(millionm3 /d) 2010 2005 A B 0 2 4 6 8 10 BillionGallonsPerDay Oil production Desalinated water • There are currently more than 15,000 desalination plants worldwide (1/4 in US). • Membranes (reverse osmosis and nano- filtration) are the most energy-efficient technology. • Costly pre-treatment of water (chlorination and dechlorination) is required before membranes to reduce membrane fouling. Water Desalinization Report, 42(35), 1, 2006 www.bp.com Ultrapure Water, 23(3), 14, 2006 VALUE OF REVERSE OSMOSIS (RO) SYSTEM COMPONENTS Annualsales($millions) Prediction U nited statesAsia/Pacific Europe M iddle East/Africa Latin Am erica/Caribbean $0 $200 $400 $600 $800 $1,000 $1,200 $1,400 Sales($millions) NewDesalinationCapacity(millionm3 /d) 2010 2005 A B 0 2 4 6 8 10 BillionGallonsPerDay Oil production Desalinated water • There are currently more than 15,000 desalination plants worldwide (1/4 in US). • Membranes (reverse osmosis and nano- filtration) are the most energy-efficient technology. • Costly pre-treatment of water (chlorination and dechlorination) is required before membranes to reduce membrane foul. Water Desalinization Report, 42(35), 1, 2006 www.bp.com Ultrapure Water, 23(3), 14, 2006 VALUE OF REVERSE OSMOSIS (RO) SYSTEM COMPONENTS Annualsales($millions) Prediction Desalination Market is Large and ScheduledDesalination Market is Large and Scheduled to Grow Rapidlyto Grow Rapidly
  32. 32. Production Equipment In a fibrous filtration system, filtration medium is a layer piled with a number of fiber-mass blocks. Periodically filtrated particles on the medium are removed by counter washing accompanied by aeration Sand filtration is widely used for water treatment.
  33. 33. Water purification by some specific fibers Activated carbon fiber. Activated carbon fiber is often used in combination with the membrane hollow fiber as a major component of water-purifying equipment for drinking water. The main role of activated fiber in the equipment is to remove such substance as chlorinated organic chemical and smell constituents. Ion-exchangeable fibers. There are some kinds of ion- exchangeable fibers. They can be effective to remove toxic ingredients of heavy metal from water. The fiber made of ion- exchangeable polystyrene resin is used for purification of recycled water from atomic power plants.
  34. 34. Reverse osmosis
  35. 35. Separation of oil and water • Oil barrier- sheet fence made of woven fabric reinforced by belt, (b) float made of foamed polystyrene covered with woven fabric, and (c) weight for stabilization. • oil-adsorptive fibrous sheet. The material of this sheet is usually nonwoven made of polypropylene (PP), kapok, or cotton. • Separating water from oil
  36. 36. Air purification • Bag filters are widely used for cleaning the exhaust gas from several kinds of incinerators. • They are usually made of glass fiber-woven fabric or synthetic fiber needle felt or its combination with woven fabric. • Polyphenylene sulfide, m-aramid, polyimide, and polytetrafluorocarbon are typically used as the synthetic fiber material • Acid gas and some other harmful gas substances can also be removed by introducing such materials as slaked lime and activated carbon in the bag. • Air filters used for the removal of dust for clean room and office • The filter medium is usually nonwoven. • Filter medium is usually pleated in the filter of high removal efficiency.
  37. 37. Air purification Air filters • Air filters used for the removal of dust for clean room and office • The filter medium is usually nonwoven. • Filter medium is usually pleated in the filter of high removal efficiency.
  38. 38. Toxic-gas removal and solvent recovery • Activated carbon fiber is useful as the key material for both the removal system of toxic gas and the solvent recovery system
  39. 39. Presented at the Fifteenth Annual Technical Conference & Expo of the American Filtration & Separations Society, Galveston, Texas, April 9-12, 2002. Electrospun fibers Contaminant Melt blown fibers Air filtration using functional nanofibers Filtration of aerosol particles  Antimicrobial air filtration Respiratory and breathing air filtration
  40. 40. Air filtration by nanofibrous web Substrate Fiber Nanofibers covered with submicron NaCl
  41. 41. Nanofiber based adsorbents and ion exchangers Schematic diagram of the nanofiber network composite fuel cell proton-exchange membrane. The inset shows the polymer matrix (a) which restricts swelling of the nanofibers and imparts mechanical strength to the membrane. The water-swollen fiber network (b) is composed of a sulfonated cation-exchange polymer shown (c) schematically and (d) in actual chemical structure form
  42. 42. Nanofiber based adsorbents and ion exchangers Adsorption of heavy metal ions Adsorption of organic compounds Ion exchange
  43. 43. Nanofibrous Microfiltration Membranes for Water Purification ∼100 nm diameter Non-woven fiber mat Breakthroughs in microfiltration: low-cost & extremely high throughput Non-woven support, with pores like coffee filter •With comparable porosity, the smaller the fiber diameter, the smaller the pore size. 0.02-1 µm thick 5 nm fiber diameter Flow direction Water with bacteria Water without bacteria Key Features Ex: Typhoid, cholera, dysentery
  44. 44. Schematic View of E-spun/Coating Composite Water Filtration Membrane Hydrophilic polymer- Impregnated E-spun layer Hydrophilic polymer coating Fine e-spun layer Coarse e-spun layer + + 2 µm Coarse e-spun layer
  45. 45. Applications
  46. 46. Applications
  47. 47. Abrams M1A1 tank with self- cleaning nanofiber filter
  48. 48. Filtration plays a major role in cleaning the environment
  49. 49. Cont… adopted three nozzles and electrospun the PA 6 nanofiber membranes with initial width of around 17 cm and the final width of 14.9 cm. the preparation process was composed of electrospinning, wetting, tension heat setting, relaxation heat setting, and coiling on the roller Fig.1—infusion pump, 2—spiral cone, 3—metallic collector, 4—electrospun nanofibrous membrane, 5—stripping rollers, 6—water bath, 7—drying rollers, 8—tension heat setting zone, 9— relaxation heat setting, 10—finished nanofiber

×