Disa In £1.2m Cleanup Project For Finnforest

At the 40 acre factory in Boston, wood is sawn and moulded into a variety of products. There are six moulding lines in the mill, five with saws for cutting the timber before it is processed.

When Finnforest acquired the factory it inherited a variety of elderly chain filter systems with open cyclones venting the extracted dusty air to atmosphere, so it was decided to replace them with a more efficient system.

Each of the moulding lines now has a DISA NFK 2000 modular chain filter, with capacities from 26,000 m3/hr up to 63,000 m3/hr, with a total air volume of 250,000 m3/hr. They are each powered by a DISA Combifab fan set sized to suit each line, with a total of 14 used throughout the project.

A pneumatic conveying line takes away the bulk of the fine dust created by the saws at source so that it does not contaminate the shavings.

Shavings from the each of the moulding lines, and any remaining fine dust, pass through the NFK 2000 filters and are discharged into an 800 cu m capacity storage silo. From there the shavings are conveyed to feed a bank of sieves that recovers most of the remaining dust, leaving the shavings virtually dust free.

The system has been designed to allow the moulding lines to keep running at all times, as the mill operates around the clock. There is a back-up 300 cu m capacity silo, to which the shavings are automatically directed should the main silo fill up. If both silos become full, the shavings can be bulk loaded under high pressure into covered trailers.

DISA used a total of 2,500m of its QF and flanged ducting for the project, which guarantees emission levels well within current environmental regulations, with the equipment intended to meet the new ATEX directive covering plant used in a potentially explosive atmosphere. The warm, extracted air is returned into the mill for space heating and can be released to atmosphere in warm weather. The modular system was designed so that additional capacity can be added should Finnforest introduce a seventh moulding line.

The self-cleaning DISA filters have allowed Finnforest to become more efficient. It used to have to shut down the old filters, and therefore the moulding line, three times a day for cleaning, which took half an hour each time. There’s also a better working environment within the mill and no problems with escaping dust.

The clean wood shavings from the moulding line are used by Finnforest to produce bales used for animal bedding. Its new wood waste plant is one of the most modern in the country, with fully automatic stacking and an online weatherproof sealing system, making the pallets suitable for outdoor storage. Finnforest specified all the ancillary equipment, with DISA purchasing, installing and commissioning the plant and supervising the construction of the new building.

Everything is PLC controlled and linked to a Scarda system, built by DISA, which is an easy-to-read, on-screen graphic displays allowing staff to monitor every aspect of the operation from the mill office, with a second display unit in the baling plant.

Sales enquiries to: DISA, Tel: 0113 273 9400. Fax: 0113 265 0735

email: sales@disacenter.co.uk
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