Effluent specialists lightened the load for Premier Foods during peak production period

Disposing and treating large volumes of waste water can be both challenging and costly for food and drink manufacturers, particularly during peak production periods. Clwyd Jones, business unit manager for Siltbuster Process Solutions (SPS) explains how, by enhancing an effluent treatment plant’s capacity, this challenge can be overcome.

“There are three main effluent treatment options: discharge direct to sewer, disposal offsite, or onsite treatment followed by discharge to watercourse or sewer. The most cost-effective solution will depend on the volume and nature of the waste water, the availability of a suitable watercourse and whether the local water company would be willing to issue a trade effluent consent for discharge to sewer.
“Tankering to a suitable licensed facility is only a viable option when there are relatively low volumes (except for difficult or hazardous wastes) and discharge to sewer or watercourse is not possible. Even then, the viability of this option will largely depend on the proximity of the treatment facility. For larger volumes of effluent, pre-treatment before discharge to sewer or watercourse is often the most cost effective solution.

“Increases in effluent volume and strength during peak production periods can put considerable pressure on existing, often undersized treatment plants, or can cause consent compliance issues if discharging direct to sewer. In this situation, companies may either have to install treatment capacity for the first time or rapidly increase their effluent treatment capacity to avoid overloading an existing plant. Without this, companies face increased operating costs, expensive trade effluent charges or, at worst, large fines.

“A similar challenge faced the infrastructure and utilities team at Premier Foods’ Ambrosia Creamery in Lifton, Devon, who approached SPS to help enhance the capacity of their effluent treatment plant during the peak production period.

“Historically, in the months running up to Christmas, the effluent treatment plant at the Lifton site became overloaded, resulting in much higher operating costs and increased risk to the treatment operation.

“During 2010, the site engaged SPS to alleviate this issue. After initial assessment, we recommended the installation of our largest mobile hire unit, a D100 packaged lamella DAF (Dissolved Air Flotation) unit, to remove solids, fats, oils and grease and the associated chemical oxygen demand (COD). This successfully reduced the COD loading on the biological treatment stage by about 30% and has ensured a stable operation with vastly reduced operating costs.

“A treatment plant which is overloaded and unstable can present real problems; costs and demands on operations staff can quickly spiral out of control, not to mention the potential effects on production. This site already had an existing balance tank and good treatment facilities but the process needed respite by reducing the load at the front end of the works.

“The D100 DAF uses established solids and liquid separation technology to generate ‘whitewater’, where microfine air bubbles combine with solids, fats and other particulates and rise to the surface of the DAF unit. The solids thicken on the surface and are automatically removed by a motorised scraper. The treated water flows onto the biological treatment stage of the treatment plant while the solids are taken away for recycling.

“The packaged design enables us to deliver and install the DAF unit in a compact area and be up and running in a matter of days, sometimes hours – minimising the risk of production downtime.”

For further information on Siltbuster, please visit www.siltbuster.com or Telephone 01600 772256