Effluent treatment specialist, Siltbuster Process Solutions (SPS), has provided a D100 dissolved air flotation (DAF) treatment system on hire to DS Smith Paper (formerly St Regis) at its Hollins Mill site in Darwen, Lancashire. The unit helped to ensure compliant discharge with no loss of production at the paper mill, and remained on site for five months.
Hollins Mill is the only UK mill that manufactures high quality recycled presentation liners – Optima Silk – as well as mottle, brown testliners and chip. The mill’s total annual production capacity is around 100,000 tonnes. DS Smith Paper has invested heavily in recent years to ensure that the mill operates sustainably through improved energy efficiency and reduced emissions.
In February, the mill began to experience settlement problems at its effluent treatment plant. Discharge Suspended Solids compliance was in danger of being compromised, causing very difficult operating conditions, so SPS was approached to provide a rapid solution. A packaged lamella D100 DAF unit was recommended, which could treat the required 100m3/hr by removing suspended solids. The unit’s compact design ensured that installation on site was particularly straightforward.
The D100, which can be installed permanently or hired, uses established solids and liquid separation technology to generate ‘whitewater’, where microfine air bubbles combine with the solids, and rise to the surface of the unit. The solids thicken on the surface and are automatically removed by a motorised scraper.
Stephen Clark, environmental supervisor at DS Smith Paper, comments: "SPS understood the pressures we were under and provided a solution in a very tight timeframe, which meant that Hollins Mill was able to continue production, while ensuring compliant discharge. The temporary DAF plant performed very well, enabling us to progress with refurbishment works to our existing treatment plant."
Clwyd Jones, business unit manager for SPS, adds: "We received the initial query on a Tuesday evening and the unit was installed and operational by the following Monday. Our ability to respond quickly like this, with the right solution, is invaluable to our customers, especially when faced with very difficult treatment process conditions."
DS Smith Paper is the UK’s largest manufacturer and recycler of paper, taking around 1.3 million tonnes of waste paper and manufacturing it into a range of high quality recycled papers each year.