The project scope includes:

• 3 (No.) travelling bridges (57 m long) supplied by SAVECO Environmental Limited
• 3 (No.) rotary lobe pumps supplied by Boerger LLC
• 3 (No.) level probes supplied by VEGA Level and Pressure
• 3 (No.) PLC control panels supplied by Te-Tech Process Solutions

PVD grease and grit removal travelling bridges are used to remove grease and grit from rectangular tanks in both municipal and industrial wastewater treatment plants.

The travelling ridges consist of a movable truck lying on two traction trolleys. One surface scraper and one bottom scraper are installed underneath the truck. The bridge is operated by a central gearbox connected to trolley drive wheels.

The tank is divided in two main parts: one for grit settling, the other one for grease collection. An air injection system installed inside the grit channel generates a circular movement, thus separating organic and floating particles from the grit. By this movement scum is conveyed into the grease collecting channel, while grit continues to settle. The bridge travels back and forth.

Travelling one way, it conveys the settled grit into the grit collection hopper through the bottom scraper. Running in the opposite direction it collects scum and floating particles by means of a surface scraper. The scrapers are operated by one gear motor only.

• Available for up to 8m wide and 50m long tanks
• Grit removal device
• Scum removal device
• Festooned cables
• Control panel
• Hot dip-galvanised carbon steel / 304 L / 316 L SS

• Quick installation
• High efficiency grit and grease removal  
• Easy installation even into existing tanks

• Cable holding chain

• +44 (0)1684 299104
• https://saveco-water.co.uk

Affectionately known as ‘The Beast’, the new screen enables tankers to directly connect and pump sludge into it, rather than offloading sludge to a holding tank that is then fed into traditional screens by gravity.

The technology has been used successfully in the US and will be introduced to treatment process at Woodhouse Mill. ‘The Beast’ is fully-automated and can quickly remove debris, plastics and other solids from sludge.

Ed Sutherland, project sponsor at Yorkshire Water, said:

“We’re always looking at innovative ways to improve the operations of our wastewater treatment works. The Beast has been tried and tested in the US and will deliver significant benefits to the operation of Woodhouse Mill. Ultimately, it enables sludge to be pumped directly into the screen, rather than the traditional method of using an upstream storage tank that feeds sludge through screens via gravity. Removing the need for an upstream feed tank will result in significant capital savings, which ultimately leads to a reduction in costs and benefits for our customers.”

"The Beast" is equipped with an integrated perforated plate VSA Drum Screen which washes, conveys, and dewaters wastewater screenings, as well as a self-cleaning screen basket and self-cleaning dewatering zone to deliver maximum efficiency.

Comprising a dual motor drive powered by independent drum and auger speeds, max flow rates of up to 200 m3/h, a drum screen 5 to 6mm perforation and incline angle of 25 degrees designed to increase solids capacity, the “Beast” can also be connected through a Perrot joint to tankers or pipes. Designed without a lower drum support arm, the Beast can be used to eliminate rag accumulation.

Rotating around its axis, the cylindrical filter conveys the screenings into a loading hopper placed in the centre. A set of spray nozzles washes the filter during operation. A screw placed inside the conveying pipe (with its top inside the discharge hopper), conveys the screenings towards the next treatment stage where organic substances are washed out. Subsequently, solids are compacted and dewatered in the compacting and drainage area and finally, solids are discharged through a discharge chute.

The Beast will be trialled at Woodhouse Mill and, if successful, will be installed at other treatment works around the region.

Saveco’s municipal wastewater sector Manager Craig Webb said:

“Achieving unprecedented success in the US market, the Beast is a game changer for how we will treat sludge going forward in the UK. We are delighted to have earned Yorkshire Water’s trust and confidence to remedy the complex challenge of sludge treatment.”

• +44 (0)1684 299104
• https://saveco-water.co.uk

At Pellows Waste Disposal Services, near Truro, a typical 4.5m³ tanker (1,000 gallons) that used to take over 20 minutes to empty, can now get back out on the road to collect more liquid waste after less than three minutes discharge time. The turnaround is due to "The Beast" made by SAVECO Environmental, that with a fully integrated 5mm screen, conveyor and compactor, all in one unit, removes harmful debris and dewaters it prior to discharge. It can handle 200m³/h and up to 6-8% solids as a plug-and-play system.

Payback is expected in just four months, as Pellows’ Director, James Martin, explains:

“The Beast has far exceeded our expectations. It injects water to accelerate the process, and is so much more efficient and robust than our previous system. Investing in The Beast is part of a major upgrade that we’ve put into place to address the big changes that have happened in Cornwall’s collection and disposal of liquid waste.”

The upgrade at Pellows, which includes a centrifuge, aeration, and larger tanks, has enabled the company (established in 1964) to expand its customer-base by offering a complete in- house service. It will also provide a potential lifeline to other contractors who collect liquid waste from the holiday parks, factories, hotels and many thousands of homeowners in Cornwall that are not connected to the sewer network.

The closure in April 2022 of what turned out to be two large disposal sites that were trading illegally, has forced contractors into sending their vehicles long distances away to discharge their collected waste. The headache has been partly alleviated by being able to take some liquids to be treated by South West Water, but during heavy rainfall and storm events, the water company has had to keep its gates closed because capacity has been reached.

James Martin continued:

“Storms and flooding from prolonged rainfall is all too common these days. We couldn’t just stop working for long periods due to the weather, letting our customers down, or keep sending our vehicles miles and miles away to unload. We had to act to protect and grow our business, so first contacted Centri Force, who make very good decanter centrifuges. They gave us plenty of good advice about how we could become independent by treating the collected waste ourselves, which included a strong recommendation of "The Beast" from SAVECO Environmental.”

The pneumatic press (with de-stoner) that had been in operation at Pellows not only took far longer to receive incoming waste, but, according to Richard Montanaro, Managing Director of Centri Force, was too small and far less sturdy, with too many areas where the process would require costly maintenance or be likely to slow or fail.

“In comparison, "The Beast" is very well designed. It is a great product that integrates very well with other parts of a plant to provide an excellent front-end pre-screen. With a centrifuge as part of a process, it gives us exactly what we’re looking for, and has helped Pellows greatly increase productivity and take this important step to becoming a liquid waste contractor with its own treatment facility".

Environmental wet waste is a big issue, and Cornwall, with far less infrastructure and sewer connections than many counties, faces some big challenges, so it is good to see Pellows play a big part in reducing the environmental impact of septic tank liquids.” Rotating around its axis, The Beast’s cylindrical filter conveys screenings into a loading hopper placed in the centre, whilst a set of spray nozzles washes the filter during operation. A screw, placed inside the conveying pipe (with its top inside the discharge hopper), conveys the screenings towards the treatment stages, during which organic substances are washed out. Subsequently, solids are compacted and dewatered in the compacting and drainage area, before exiting through a discharge chute.

Despite septic tank contents often containing solidified calcium, rocks, stones, and sanitary products, installation of The Beast now sees Pellows’ 27-tonne artics discharge waste in less than 13 minutes, compared preciously (depending on the thickness of the liquid) to 45-minutes, up to one hour.

Craig Webb, SAVECO’s Municipal Sales Engineer, commented:

“We have worked closely with Pellows and Centri Force to bring about a big improvement in treating liquid waste. Allowing effluent to be put directly through "The Beast", which avoids placing further stress on an existing plant, is also a huge benefit to water companies. Liquid waste contractors and the water industry can see that by screening, washing, conveying and dewatering - all in one unit - there is a reduction in risk, and the opportunity to make big savings by removing the need for multiple pieces of equipment.”

James Martin from Pellows, continued:

“The whole system is so much better now. We get better biosolids too at the end of the process. Apart from South West Water, we’ve now become the first company in the County who have the capability to treat liquid waste for safe disposal into the foul sewer main.”

• +44 (0)1684 299104
• https://saveco-water.co.uk