Industrial Filter - Basic Filteration, Filter-Housing, Filter Media, cartridge, Process Filter Manufacturer, Exporter & Supplier in ahmedabad india

There are various filtration & separation procedures follows by industry for removal of un-wanted particles (contamination) like:

Centrifuge
Continuous vacuum filter
Disc type knife filter
Filter press
Cartridge filter (Micro filtration)
Dialysis
Electro dialysis
Reverse osmosis
Ultra filtration /Neno filtration system

Basic difference between Micro filtration, Ultra filtration & R.O:

0.0001mm 0.001mm 0.2mm 10mm*

1A⁰<-----------> 10A⁰ <-----------> 200A⁰ < -----------------> 100,000A⁰

Reverse Ultra Microfiltration
Osmosis Filtration

mm – Micron
Smallest pencil dot, which we can see by necked eye, is about 40mm.
Relative comparison

MICROFILTRATION (CARTRIDGE FILTER) :

Filtration for the removal of suspended particles from the range of 0.2 mm to 100 or 150 mm is known as micro filtration or cartridge filter. This is pressure filter in line as shown in the picture:

Pressurized fluid come in to the housing and passing from the cartridge where actual filtration takes place and contamination retain on the cartridges and clear fluid comes out from the center of the cartridge. This is out to in system.

One needs to monitor the filter by pressure difference (delta P - the difference in inlet pressure and outlet pressure). Initially, when cartridge is fresh, delta-P will be minimum and as it got contaminated, delta-P will increase gradually. At 2.5 or 3 Kg/cm ² g delta-P, one needs to change the cartridge, if it is disposable or clean the cartridge in case of re-usable cartridge.

If the flow rate is more, we need to give more number of cartridges in one housing as shown here.

TYPE OF CARTRIDGES :

Depending on filter media we can classify the filter cartridges as depth or surface filter. Also they are available in various materials like, Polypropylene, Cotton, Cellulose, Glass-fibre, Nylon, Teflone, Ceramic, S.S. Screen, Sintered S.S. or Bronze etc…

SURFACE FILTER:

Filter media where the pores are within the same 'Plane' i.e. Screen or Surface filter as shown in the picture here:

DEPTH FILTER:

pHOTO

filter media where the pores are distributed throughout the thickness of the medium. Particles are stopped both on the upstream surface and within the medium.

STANDARD CARTRIDGES:

Generally cartridges are available as per international standard in 10", 20", 30" and 40" length cylinders. O.D. of the cartridge is approx 70 mm and I.D. is 25 mm. They are available in different end connections like Double Open End - "RF" Style, Double Open end with Gasket, Code-7 type, Code 9 type etc…as shown below:

STANDARD CARTRIDGES

Generally cartridges can classified as pleated or depth type.

PLEATED CARTRIDGE:

In pleated cartridges, actual filter media is in pleated form to cover more surface area. It is pleated on perforated core. It is supported with any other media, which is coarser to give minimum pressure drop and good strength to the cartridge. Outer cage is provided to give mechanical strength to the cartridge.

Paper, S.S. wire-mesh, polypropylene, Nylon - N66, Polyethersulfone, Fluropolymer, Glassfibre or PTFE material pleated filter cartridges are widely available.

Most precise filter elements for guaranteed removal efficiency is pleated polymer cartridges.

DEPTH CARTRIDGES:

Polypropylene, Cotton, Nylone, Cellulose, Ceramic, Sintered S.S. & Sintered Bronze media are available in depth type cartridges. Many manufacturers make graded pore structure depth media, which gives efficient filtration because of proper pore distribution.

As shown here, Cross section of graded pore structure cartridges, bigger particles retain on the outer surface of the cartridge and most upper layer of the cartridges. While smaller particles retain at inner and very small particles retains at the inner layer of the cartridge. Thus entire depth of the cartridge utilizes and hence filtration is very economical.

Thus graded pore structure depth filter cartridges are good pre-filter, because it traps bigger particles then its rating.

NON STANDARD S.S. WIRE-MESH CARTRIDGES:

For coarser filtration (25 micron and above) S.S. wire-mesh filter cartridges are widely used. Advantage of this media is, it is cleanable filter media. The cartridge can be pleated cylindrical or wrapped cylindrical. Now a days welding joints is possible and hence it can be used for wider application. Earlier it was only possible with epoxy joint, which has a limit of temperature up to100° C. These cartridges can be pleated with supporting coarser media and made any size of cartridges up to 1000 mm.

FILTER SELECTION & SIZING :

Following parameters are to be considered for selection of the filter:

Fluid to be filtered
Flow rate
Filtration rating (Micron - Cut off)
Operating Pressure
Operating temperature
Viscosity of the fluid at operating temperature
Filter material (Chemical compatibility)
Load of suspended particles
Continuous or batch process - Batch size etc..

Based on chemical compatibility of the fluid at operating temperature, we need to select the filter cartridge material. Almost all cartridge manufacturers gives flow rate Vs pressure drop graphs of the cartridge. Based on the graph, and viscosity of the fluid, we have to decide the size and number of cartridges and design the filter housing to house the cartridges.

To make the system economical, if required, we need to give pre-filter. May be re-usable cartridges, which removes major contamination and enhance final filter's life.