Presentation is loading. Please wait.

Presentation is loading. Please wait.

The Concept of the Basic Liquid

Similar presentations

Presentation on theme: "The Concept of the Basic Liquid"— Presentation transcript:

1 The Concept of the Basic Liquid
技術研討資料 Millipore Corporation has always been at the forefront of filter membrane development and characterization for the Microelectronics industry. We are focused on continuing improvements to test methods in an effort to provide solutions to our customers' contamination controls problems. Retention of particles is the most fundamental require- ment of any chemical filter. Any filter must be capable of removing the majority of particles from the liquid stream This presentation will review our latest progress in particle retention testing of Teflon filters, as well as test results from third party studies. 主講人 : 龍仁生

2 Topics The key point to the filter Filter Cartridge Filter type
Depth fiber, Membrane, Hollow Fiber… Filter Device Membrane, Support… Membrane Characteristic Retention Wet-ability --- De-wet Filter Housing SS, PFA, PVDF,PP… How to choice an optimal filter

3 The key to filter in Chemica
The Filter pore size / Retention How much ? 0.1um, 0.2um… Lower filtration rate, Higher retention The Chemical Compatibility / Pre-wetting PTFE UPE PP Nylon Cleanness Low Hold Volume

4 Typical Depth Filter Structure

5 Manufacturing Process
Stretched Polymeric Membranes e.g. PTFE

6 Manufacturing Process Cast Polymer Membranes e.g. PVDF

7 Manufacturing Process
Membranes Track Etched e.g. Polycarbonate

8 Membrane Characteristics
"Pore size" (maximum pore size = "retention rating ) The largest sized pores in a filter "Porosity" A measurement of the openness of a filter i.e. 80% porosity equates to 80% open volume, 20% material "Pore size distribution" The range and frequency of pore sizes which make up a the filter That is why HA

9 Typical Filtration Devices:
Pleated Cartridges Permeate Flow Path Inlet Flow Path Filter "pack" contains membrane, plus upstream & downstream fibrous supports. Supports can be a source of particles . Pulse pressure is a potential shedding source It is not easy to prewet and flush.

10 Typical Filtration Devices: Stacked Disk Cartridges
Downstream components are rigid and cleaner than other membrane supports. Excellent in pulse pressure shedding. Horizontal disks prevent efficient gas venting Fluid Flow Path Permeate

11 Typical Filtration Devices: Hollow Fiber Cartridges
Filter area can be greater than pleated structure Benefits of self-supporting, high surface area, high flow. Used mostly in water filtration and photochemical. Low pressure drop

12 Filtration Retention Mechanisms:
Capture by Sieving / Interception --- Hard Particle--- Bridge/ Cake effect Soft –Gel/Micro-bubble Hard Particles Soft Particles

13 Retention Mechanisms:
Capture by Adhesion / Adsorption + Very small particles in liquids have a negative charge and can be captured by attraction to a positive charge in a filter

14 過濾在時間的變化 particlel Time 壓差 Time


16 Hydrophobic Vs Hydrophilic
Wetting smoothly with, water.". No pre-wetting Hydrophobic: Fear of water; Tending not to combine with water. Requires pre-wetting.

17 Hydrophobic Vs Hydrophilic
Contact Angle is the measure of Wettability i.e. Low contact angle = Hydrophobic High contact angle = Hydrophilic Hydrophobic < 90? Hydrophilic No contact angle 90? > 90?


19 What is Dewetting and how can it
impact a process? SC1 SC2 H2O2 NH4F Piranha

20 Non-Dewetting Technology
QuickChange Filters are Non-Dewetting SC1 SC2 H2O2 NH4F Piranha Non-Dewetting Technology

21 Prewetting Flow in one direction (prevents air entrapment)
Drain Flow in one direction (prevents air entrapment) Flow from upstream side into core 60:40 IPA water solution Flush with DI water

22 Filter Housing POU typically single 10" filter housing
Materials of construction: PFA, PVDF, PP, SS

23 Filter Cartridge Housing
Inlet Outlet Typical Flow Path T-Line Design In-line Design Inlet Outlet

24 Filter Cartridge Housing
Inlet Outlet Typical Flow Path T-Line Design In-line Design Inlet Outlet

25 T-Line Mounting Considerations
Bowl Down (top of the head points toward ceiling) Easier to drain upstream side of filter Air does not get trapped in core Liquid remains in core after drain 20" can be difficult to mount filters Inlet Outlet

26 T-Line Mounting Considerations
Bowl Up (top of the head points towards the floor) Complete draining of filter core Easy filter installation Recommended configuration for 20" housings Liquid drains from upstream side of filter Must vent downstream side of housing Vent Drain

27 Reduced Tool Space Required
A typical tool design requires enough space to lower the bowl below the cartridge for filter changeout. With Chemlock, the bowl only needs to be lowered below the head, then the cartridge and bowl can be removed as a single unit. Tool Space Savings - Approx. ~ 8 inches! 18” in space savings with 20” bowl

28 Typical Disposable Filter Assembly
outlet Vent Drain Internal Filter Element inlet Connections : Flartek, Butt Weld, etc.

29 Disposables Vs. Housings
Traditional design Flexibility - 4" - 40" Requires O-ring change Increased contamination risk Greater material selection Easier customization Limited Temp ( ~100C ) Disposables More compact footprint Cleaner no o-rings/seals no handling of element Easier for prewetting Improved safety Higher Temps ( 180C )

30 Variables Which Effect Retention
Membrane Contaminant Fluid Conditions Structure - cast - stretched - irradiated Charge Pore size & pore size distribution. Porosity* Thickness Etc. REF.<C01> Type: - solvent - acid - base - mixture Viscosity* Flow rate/face velocity Temperature Pressure: - pulse - differential

31 Summary Two major filter types Filter Wetability
Five major filtration mechanism 1.Cake filtration 2.Size exclusion 3.interception 4.adhesion 5.adsorption Two major filter types Depth filter—Pre filter-dirty process Membrane filter – Final filter-precision filtration Filter Wetability Hydrophobic membrane – used for solvent Hydrophilic membrane –Not need to prewet for water base chemical Filter Retention Defined by pore size and LRV Affected by Pore size distribution and pore size definition

Download ppt "The Concept of the Basic Liquid"

Similar presentations

Ads by Google