Water & Wastewater Treatment

WASTEWATER TREATMENT 21 February 2014 Water & Wastewater Treatment Separation system The project with Kelda Water Services at Royal Marines Base Chivenor in North Devon was different again. Here, the project involved providing a temporary solids/liquid separation system whilst the existing final settlement tank was refurbished. Normally solids liquid/separation on an activated sludge plant is carried out using a FST. However, as this was only a temporary installation, a D100 portable DAF unit was provided instead. Whilst the use of DAF for sludge thickening applications is well documented, they are still relatively unused on municipal sites. DAFs are ideal for this sort of temporary application because they are small and portable – they can be brought to site and installed via a lorry-mounted crane. They are also ideal for emergency situations where fast and flexible deployment of kit is needed. For example, at Chivenor, due to access constraints the original intention was to install the unit using a crane. However on the agreed delivery day the wind speeds were too high for the crane to operate so the unit was delivered and installed using a lorry-mounted Hiab. This allowed the unit to be positioned via a low-level lift, out of the wind. Operator control DAF systems are easier to manage - the DAF operator is in control of the solids/liquids separation process, so the treated water clarity and density of the floated off sludge can be controlled. Compare this with a conventional clarifier where performance is dictated solely by the settlement characteristics of the sludge. For example, at Chivenor, the D100 was fed at a rate of 43m 3 /h of mixed liquors with a suspended solids concentration of 3,500mg/l and produced a treated water to meet the 30mg/l TSS site consent and a return activated sludge concentration of 3% solids. Maintenance-led programmes Moving into AMP6, water companies are becoming more and more maintenance-led and SPS is seeing more and more requests for assistance with the water companies to work with them to build such solutions into their programmes. When it comes to asset upgrade, they need to consider that solutions that are right for the long-term. Short-term fixes need to be small, quick, easy and cost effective – and DAF technology is a viable solution in many cases. DAF can provide additional treatment capacity during upgrade works and also ensure compliance is maintained, in a low-risk way. DAF also offers a short-term solution for water companies, buying them valuable time to consider the optimal long-term solution in terms of plant upgrade. nnn AB13-686 www.michael-smith-engineers.co.uk Runs Dry for Hours Guaranteed for Years Perfect Self-Priming PUMPS ✓ SP Series pumps are perfect for emptying IBC's, drums, tanks, sumps & bunds.If you need to transfer liquids that are clean, contaminated or dirty... ● Self-priming – up to 7.6 metre lift ● Flow rates up to 45 m3/hr ● Available in polypropylene or PVDF ● Magnet drive – leak free ...Choose FTI SP Pumps the safe and reliable choice Finish Thompson SP Series – the safe solution for all your liquid chemical transfer Temporary lamella DAF installation at Brockenhurst wastewater treatment works in Hampshire

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