Project LA – Junkers furnace extraction

The cartridge filter is to purely control the dust emissions from each furnace which at present only run one at a time. 

The reason for this new filter is to comply with the new dust emissions regulations set out by SEPA.

Originally the dust was emitted to atmosphere and the dust was extracted via two fans (duty standby)

We replaced one of the fans and the other is going to be used as a backup for when the filter is offline for maintenance.

The new cartridge filter installed has a volume capacity which will allow both furnaces to run simultaneously for future proofing in case the production needs to be ramped up.

Filter Designs was responsible for the design, fabrication, installation, and commissioning of the filter system. The filter was pre-assembled at the fabrication site to save time on site, also so the lift from the delivery lorry to the assembled support structure would be a straight and easy lift.

Both this project and the LA Cast shop were both ordered at the same time and as the cast shop project we were able to use a local fabrication company who were familiar with the site, to fabricate the ducting and staircase and carry out the installation to allow us to save the client some money. 

Filter Details:

• cleanPULSE Reverse Jet Cartridge Filter

• Filter arrangement 6 rows x 7 cartridges

• Ø200mm diameter x 1000mm 

• Filtration gas volume 15,000Am3/hr

The filter itself is a reverse jet cleanPULSE filter designed specifically for the requirements in-house using our 3D Inventor capabilities. The filter has 42 vertically hanging cartridges and a pulse cleaning tank to ‘pulse down’ the cartridges based on differential pressure.

As this filter was for dust extraction only, we opted for a cartridge filter to allow us to keep the footprint to a minimum to utilise the space requirements on site.

The antistatic cartridges offer a much larger filtration area to allow a much more compact design.

The cartridges are accessed via the top access door which is opened with aid of gas struts.

Project Summary

The equipment broadly compromises CPC cleanPULSE cartridge filter with a free-standing access stairs and access walkway and built-in step to access the top of the filter. The filter discharge system is a rotary valve into a bulk bag and this can be controlled via the stop start button on the filter leg which allows the operative to stop the discharge sequence whilst the system is online to change a bulk bag.

The inlet ducting was designed to keep the existing hoods/internal connections as these were still in good condition.

We installed a manual blast gate damper to allow the filter to be closed off for any maintenance work which would then allow the existing fan to put back online whilst any work was carried out which meant that production did not have to stop. 

The outlet ducting was also designed to enable us to reuse some of the existing chimney and the emissions monitoring they had. We needed to replace a 3m section on the top of the chimney which had corroded over time.

The main fan is controlled via a VSD so that when only one furnace is operational the system can be turned down to offer some power savings on site.

The controls system was a bespoke design which had a small HMI for functionality. 

This allows the users to easily change any settings track trends and monitor any alarms which may arise which make troubleshooting much easier.

Report by Darren Jones - Filter Designs Ltd - March 2021