FabriCleanTM

Pulse-Jet Fabric Filters

Pollution control legislation throughout the world is becoming more stringent and higher standards of collection efficiency and reliability are demanded across the whole range of power, process and manufacturing industries.

F.L.Smidth Airtech FabriCleanTM Pulse-Jet Fabric Filters are used throughout industry on a wide range of applications. They provide sound technical and commercially attractive solutions on processes which demand high collection efficiencies with related low dust emissions.These filters require an absolute minimum of attention and maintenance.

Installations range from a small single compartment unit up to multi- compartment systems operating as part of a complex, total gas cleaning plant often involving other types of pollution control devices.

Use of the FabriCleanTM Filter gives many benefits Optimised gas flow distribution

system. Multi-compartment concept allows

flexibility of system design. Use of standard components

minimises costs. Improved Filter Bag and Cage

design. Venturi fitted to Bag Cage

enhances pulse cleaning. SmartPulse ControllerTM system

reduces power consumption. Easy access for filter bag change

and inspection. Operating temperatures up to 250 0C Reference plants in excess of

1,000,000 m3 per hour. Continuous improvements from

the Barrier Filtration Technology Centre.

The FabriCleanTM Filter is part of the F.L.Smidth Airtech range of pollution Control equipment which also includes Ceramic Filters, Dry and Wet Type Electrostatic Precipitators, Precipitator Control Systems and Acid Gas Scrubbers and Absorbers.

Design Features HIGH EFFICIENCY Dust collection efficiencies of greater than 99.9% are readily attained with careful selection of filter media and operating parameters. Novel design of the inlet duct permits high inlet dust loading with only a moderate pressure loss.

CONTINUOUS OPERATION Automatic, effective bag cleaning using pulsed air, microprocessor controllers, on-line" or "off-line" cleaning to suit application requirements, "on-line" maintenance option on multi- compartment units, high plant availability.

EASY MAINTENANCE Walk-in, weatherproof weather enclosure, no internal moving parts, minimum bag wear, simple bag change, generous access.

COMPACT LAYOUT Flexible modular design, high integrity construction, minimum ground space, short lead time.

Plant Components The FabriCleanTM system comprises individual compartments, inlet and outlet flue gas duets, isolation valves, pulsed cleaning system, access facilities, support steel, process and instrument controls and dust removal equipment. F.L.Smidth Airtech will also supply other components such as fans, process ducting, coolers, dust transport and storage silos and sorbent injection systems at the clients request.

Gas Distribution The high performance of the FabriCleanTM Filter is achieved by careful design of the gas flow distribution system. Dirty gas enters the inlet duet from the process and flows through the inlet valves into the individual compartments containing the filter bags. Baffles and deflector plates ensure that most of the dust is deposited directly into the hoppers, reducing the dust burden to the filter bags. This results in a significant decrease in the amount of pulse air required to clean the filter bags, so achieving lower power

Cleveland Waste Managements' Energy from Waste plant in England with fabric filters supplied by F.L.Smidth Airtech

FabriCleanTM

Pulse-Jet Fabric Filters

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Gas distribution screen

The FabriCleanTM Pulse-Jet Fabric Filter System

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1. Inlet duct 2. Top box lid 3. Outlet damper 4. Inlet damper 5. Outlet duct 6. Hoist 7. Weather enclosure 8. Purge tubes and venturies 9. Compressed air manifold

10. Casing 11. Hopper heating 12. Distribution screen 13. Insulation 14. Screw conveyor 15. Support 16. Stair case tower 17. Bags and cages 18. Air sluice

High efficiency gas/dust distribution

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1. Raw gas inlet 15-18 m/sec 2. Inlet to compartment 3. Dust extraction 4. Gas is distributed and goes through distribution screen5. Dust down flow between bags 6. Clean side of filter 7. Clean gas outlet 8. Collected dust 9. Dust drop out

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Gas/dust distribution

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1) Raw gas inlet 2) Clean gas outlet 3) Guide vanes 4) Dust drop out 5) Baffle plates (One of more options) 6) Distribution screen (Shown schematic) 7) Collected dust

consumption and extended bag life. A further series of baffles ensure even

distribution of the partially cleaned gas to the bags which are suspended from a tube sheet, separating the dirty" and "clean" sides of the filter. Under suction generated by the induced draft fan, flue gases are drawn through the filter bags with the particulate being retained on the outer surface. A rigid wire cage is installed inside the bag to prevent its collapse. The cleaned flue gas passes through the open top of the filter bags into the cleaned air chamber and then exits the filter through the outlet valves and cleaned air duet.

Pulsed Cleaning System The build-up of particulate on the outside surfaces of the bags creates a dust cake increasing resistance to gas flow, resulting in an increase in pressure drop, and must be removed periodically by the bag cleaning mechanism.

Each row of bags in a compartment is individually pulsed with compressed air delivered through a solenoid actuated diaphragm valve.

Energisation of the valve allows compressed air from a manifold to flow rapidly into the attached purge tubes and through the holes that are positioned over the venturis on the bags. This instantaneous surge of compressed air creates a shock wave which goes down through the bags causing the fabric to snap away from the support cage, dislodging the dust cake. The cleaning of each row is carried out in a fraction of a second, allowing the filtering operation to continue without interruption. The dislodged dust cake falls into the hopper from where it is extracted.

This type of operation is called "on- line" cleaning, i.e. all the rows of bags are inoperation except the specific row being cleaned.

Rawang, Malaysia, Fabric Filter for a clinker cooler.

Compartment Isolation Some processes or customers' specifications require the need for "off- line" cleaning. In this case the outlet isolation valves to a compartment are closed, isolating it from the gas flow whilst a cleaning cycle is initiated, cleaning each row of bags in turn within the isolated compartment. After completion of the compartment cleaning, the outlet valves are opened and the compartment goes back into operation.

Some clients require very high plant availability and hence the need to carry out maintenance whilst the plant is "on- line". Both the inlet and outlet isolation valves of a compartment are closed and locked manually allowing safe access for maintenance, bag inspection, bag change, etc, whilst the other compartments remain "on-line". Once completed the valves are opened and the compartment returned to operation.

Valve operation is fully automatic and is controlled from the filter control microprocessor control system.

Casing, Hoppers and Supports The FabriCleanTM filter units including the casing, bag support cell plate and hoppers, are constructed from steel plate, stiffened and sealed to withstand at least 5,000 Pa. More onerous conditions can be catered for by increased stiffening.

Internal division plates are also stiffened to withstand the differential pressure when one compartment is open for maintenance / inspection or in "off- line" cleaning mode.

The dust dislodged from the filter bags is deposited in a hopper located under each compartment. Pyramid or trough type hoppers are provided as appropriate to the application and operation. They can be trace heated and supplied with agitation equipment to ensure effective discharge. Collected dust is removed via seal valves, screw or drag link conveyors, depending on the type of dust being handled or client's own requirements.

Weather enclosure An optional fully weatherproofed, walk-in to weather enclosure can be provided covering the entire top area of the fabric filter. This enables all inspection, maintenance, etc., to be carried out sheltered from the elements.

Cimpor Souselas, Portugal. Fabric Filter for a cement kiln

Dalmacija, Sveti Kajo, Croatia. Convertion from Electrostatic Precipitator to Fabric Filter

Inside a weather enclosure

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Filter Bags and Cages Filter bags are normally 127 or 150 mm (5 or 6) diameter and are available in lengths of 2.5, 3, 3.5, 4, 5, and 6 meters.

Filter bags are sealed into the tube sheet using a snap band and are reinforced at the top and bottom to prevent wear. The fabric used is selected from the wide range available, by our experienced technologists, to meet the process needs and to withstand the process operating conditions. Full details are provided in our project quotations.

For ease of assembly and subsequent removal of long filter bags, the wire cage can be split into two sections using our proprietary centre fixing.

On the top (clean side) of the tube sheet the bag cage extends to hold a

Advances in filter bag materials can give emission levels of less than 5mgINm3.

venturi which fits directly under the pulsed air outlet hole on the purge tube.

Access to purge tubes, venturis, cages and bags is through an access cover located in the floor of the top housing.

SmartPulse ControllerTM Fabric Filter Optimisation System On large fabric filters once the main design parameters such as flow distribution, filtration velocity and cloth type have been selected, the major contributing factor to power

consumption, compressed air usage and bag life, is the operation of the pulsed cleaning system.

The FabriCleanTM Filter is supplied with the SmartPulse ControllerTM which in addition to operating the normal pulsing system has many innovative features for performance monitoring and Control.

One of the outstanding additions to normal Control is the automatic diagnostic feature which will look at pulse duration, interval and pressure with relation to filter differential pressure and automatically adjust these parameters to give the best use of compressed air and fanpower ensuring the most efficient pulsing is achieved.

Research and Development Pilo units and large scale bag filter models are constructed as part of the continuous research and development programme undertaken by F.L.Smidth Airtech . Positive results are incorporated within the standard fabric filter design to optimise gas and dust flows. Improvements will reduce dust re-entrainment, pressure drop, bag wear and pulse air cleaning requirements.

Different types of bag material

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Laboratory tests

SMART PULSE CONTROLLER

Maintenance, Bag Removal, and Replacement Access to bags, cages, purge tubes and venturis is from the cleaned gas side of the filter through the top cover of each compartment.

A runway beam and hoist is provided to lift the opened top cover clear of the floor and move it aside. This provides safe and easy access to the compartment purge tubes and the tube sheet area.

The bag, cage and venturi assemblies are mounted on the tube sheet and no special tools are required for removal and subsequent replacement.

Maintenance time is reduced to a minimum and a bag/cage assembly can be removed by one person in 2 to 3 minutes.

There are no moving parts inside the gas chamber or above the tube sheet.

Applications and Experience Its reliability, versatility and cost effectiveness has won universal acceptance for the FabriCleanTM Pulse-Jet Fabric Filter across a very wide range of industrial processes that produce dry dust that has to be removed from the gas stream. Principal applications areas are: Cement - Plastics Production Minerals - Metallurgical Processes Food and Dairy Industry - Foundries Iron and Steel Production Power Generation - solid fuel boilers Energy from Waste plants - refuse and biomass incinerators Clinical Waste incinerators

Fabric Filters are often the principal item of gas cleaning equipment in a particular process but they can also form part of a total gas cleaning equipment plant involving Acid Gas Scrubbers where the Fabric Filter can be used as a supplementary reactor providing a high level of reaction as well as particulate removal.

F.L.Smidth Airtech offer a comprehensive range of gas cleaning equipment for all the major industrial processes.

Bag, cage and venturi assembly is easily removed and replaced.

Their range includes Dry and Wet type Electrostatic Precipitators, Acid Gas Scrubbers, Semi-Dry and Wet Absorbers, Fabric Filters and Ceramic Filters. Whether you require a simple flange-to- flange dust collector or a turnkey installation, we can provide a complete service. Our scope covers the complete design, manufacture, supply, site erection, commissioning and testing of the most suitable plant for any given application.

F.L.Smidth Airtech also offer an inspection and maintenance service together with plant refurbishment and performance upgrade if this is required. This includes conversion of existing air pollution control equipment to the FabriCleanTM Pulse-Jet Fabric Filter.

F.L.Smidth Airtech equipment is custom designed to contract specifications. Equipment performance will be as established in each contract, and may not be as generalised in this brochure.

FabriCleanTM and SmartPulse ControllerTM are trademarks of Lodge Sturtevant Limited a member of F.L.Smidth Airtech group

Easy Maintenance

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Focus on Site Activities

The FabricCleanTM Pulse-Jet Fabric Filter has been designed for quick and easy construction and commissioning. Where it is practical pre-tested / pre-assembled units are used to ensure quick construction and eliminate unnecessary time spent on fault finding. By this method any fault will be discovered at an early stage so a proper correction can be implemented. The filter can be delivered to site in panel form (Flat-Pack) or in pre-assembled modules appropriate to transport, site location and restrictions. To reduce construction time the casing and hoppers can be pre-assembled and insulated on ground level and lifted into its final position on the support. This will also reduce the extent of scaffolding. The SmartPulse control system is delivered to site in pre-cabled control boxes for easy erection and commissioning. This significantly reduces the electrical work on site as these cables represent approx. 75 % off all cables on the filter top.

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Pre-erected and pre- insolated casing

Pre-erected hoppers and topboxes

Pre-erected weather enclosure

SmartPulse control system

F.L.Smidth Airtech Ramsingsvej 30, DK-2500

Valby Copenhagen, Denmark

Tel.+45-3618 2000 Fax.+45-3618 2030

E-mail: info@flsairtech.com www.flsairtech.com