Experts in air filtration


At the heart of almost everything we do is a filter. Through the years we have developed a range of filters that you can trust.

Under our cleanPULSE brand, we offer 3 different filter types, all of which take out harmful particles from the environment.

We have:

  • cleanPULSE bag filters
  • cleanPULSE cartridge filters
  • cleanPULSE ceramic filters

They are named cleanPULSE, because they CLEAN the harmful emissions from the environment, and have a reverse jet PULSE cleaning mechanism. 

This has become the best available technology to meet the latest emissions regulations, which become ever more demanding on system performance.  The difference in the filters is the choice of media and how this affects the filter system.

Filter Designs typically offer the following:

cleanPULSE bag filters

  • Gas volume – any
  • Filter media type – filter bags typically 2m to 5m long and 130mm diameter
  • Temperature range – limited by the media type, ambient to 260ᵒc continuous operating temperatures
  • Key advantages – wide range of application, temperatures suit reagent injection, flexible in application
  • Key disadvantages – space requirements, temperature limitation, process gas characteristics and filter media type need to be matched

cleanPULSE cartridge filters

  • Gas volume – any
  • Filter media type – pleated cartridges, typically 1m to 2m long and up to 350mm diameter
  • Temperature range – limited by the media type, ambient to 120ᵒc continuous operating temperatures
  • Key advantages – compact size and therefore cost
  • Key disadvantages – application restrictions, temperature limitations

cleanPULSE ceramic filters

  • Gas volume – any
  • Filter media type – filter elements typically 1m to 3m long and up to 150mm diameter
  • Temperature range – beyond the limitations of the filter steel/stainless steel enclosure, above 1000ᵒc
  • Key advantages – high temperature capability
  • Key disadvantages – increased cost, lack of mechanical movement when pulse cleaning, fragile elements

All our filters are bespoke, and can be designed for any application and space. We have an automated CAD program that will quickly produce a 3D model to show our clients.  We can design a filter to be tall, long, thin, wide, to suit almost any site restriction.

Depending on the application, the systems can also be with or without offline cleaning and on-line maintenance. Our systems generally have inverter-driven fan units and hence flow and pressure control to maintain a constant negative pressure at the outlet of the process.

More on… cleanPULSE bag filters

For many years, Filter Designs have produced high-temperature cleanPULSE bag filters for filtering high-temperature gas from a variety of applications. Some of these include:

  • Secondary Aluminium Smelting
  • Glass production
  • Clinical waste incineration
  • Chemical waste incineration
  • Gasification
  • Pyrolysis
  • Coal-fired boilers
  • Tallow power generation
  • Syngas Filtration

These filters normally have tubular bags varying in length from 2m to 6m, and are made from high-temperature materials such as PTFE on Glass, P84, Nomex and cleaned by reverse jet pulsing with compressed air. They have a maximum temperature limit of around 260°c.

The systems need careful design and often incorporate equipment to remove acid gases, dioxins, furans, and heavy metals using dry reagent injection (see CleanPAC, CleanSORB). As required, we offer the removal of oxides of nitrogen (de-NOx) using SNCR and urea solution or prill using our own proven designs.

The filters are designed to ensure efficient operation and protection of the filter system with the supply of spark arrest, detection and water quenching systems, including air dilution as required.

If you would like more information about our cleanPULSE bag filter range, or indeed any of our other products, please don’t hesitate to give us a call on 01858 419104 or complete the enquiry form.

More on… cleanPULSE cartridge filters

Filter Design also produces cartridge filters usually for dust / fume extraction where space a limited.

Due to the pleated nature of the cartridges, it allows a greater filtration surface area than bags, thus reducing the overall size of the filter.

Cartridge filters are good for low temperature filter applications with a maximum operation temperature of 120°c.

The cartridges come in a variety of size varying in width and length with up to 24m2 filtration area per cartridge.

If you would like more information about our cleanPULSE cartridge filter range, or indeed any of our other products, please don’t hesitate to give us a call on 01858 419104 or complete the enquiry form.

More on… CleanPULSE ceramic filters

Our cleanPULSE ceramic filter is an ideal solution when high temperatures are involved, although they offer challenges which a bag filter does not. The ceramic media from any of the suppliers below can reach and exceed 1000˚C but consideration must be given to the materials of filter construction and the impact of temperature. Stainless 316 and stainless 310 are options which offer no fabrication issues but do come at higher costs when compared with mild steel.

A ceramic filter using candles at these temperatures requires specific design changes to account for expansion, heat transfer to the pulse control system and any adjoining staircase, CAT ladder, ducting cantilever support or other metallic connection. Filter Designs use a ceramic based heat break material to stop the heat transfer.

At these high temperatures, options such as offline cleaning require valves with externally mounted ‘outrigger’ bearings and tolerances suited to the temperature range. The ID fans, ducting, differential pressure monitoring devices, pulse control, screws and rotary valves, insulation and cladding in these systems all must be designed to accommodate the elevated temperatures.

We have incorporated various suppliers and sizes of filter elements into our designs, and these include:

  • Glosfume elements
  • Clear Edge (Cerafil)
  • Tenmat
  • Brightcross
  • Unifrax

Ceramic elements can be supplied in different sizes to suit the gas volume and application. The filters can be incorporated into our cleanPULSE range of reverse jet (pulse jet) ceramic filters and they can also be tailor-made to fit your exact requirements so that they suit your application perfectly.

If you would like more information about our cleanPULSE ceramic filter range, or indeed any of our other products, please don’t hesitate to give us a call on 01858 419104 or complete the enquiry form.

More from us

Get in touch

T: 01858 419 104

E: [email protected]

Our recent Projects

We were contracted to provide 2 small Ceramic filters suitable for a small volume but with a design maximum temperature of 600°C. In addition the filters will be handling a syngas which cannot be mixed with oxygen so an alternative to compressed air would need to be used for the ‘Cleanpulse’ cleaning of the 25 Ceramic element in each of these CPC78 filters. In addition dosing of small amounts of a re-agent is required so the client also opted for a ‘Cleandose’ 25kg bag skid. Find out more about Project CAD below.

Project SRCL HH - GSA (Gas Suspension Absorber) Reactor Tower

Project BCI - Bag Filter, Gas Suspension Absorber, Reagent Dosing for a Challenging Carbon Process

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