Siltbuster will present its "Big pHil" at UK Concrete Show

Siltbuster Limited is soon revealing ‘Big pHil’, the latest in its range of Concrete Washout Solutions at the UK Concrete Show at Coventry’s Ricoh Arena on 22nd February.

A larger and more versatile version of Siltbuster’s groundbreaking RCW (Roadside Concrete Washout) unit, ‘Big pHil’ provides on-site capture, treatment and neutralisation of high pH cement laden washwater runoff from a wide range of concreting plant equipment, including crane skips up to 2,000 litre capacity, concrete pumps and the like.

This newly developed, fully integrated system, is built on a 6m long transportable hooklift platform and is the latest in the range of innovative and popular carbon dioxide (CO2) pH adjustment systems from Siltbuster but with the added benefit of providing washwater recycling to further reduce the need to discharge water off-site.

Like Siltbuster’s other pH adjustment systems, the use of clever chemistry is at the centre of Big pHil’s treatment process which also includes:

· Receiving and segregating waste concrete from the dirty washwater;

· Treating the washwater to remove the gross suspended solids;

· Automatically reducing the pH of the washwater;

· Settlement of any solids precipitated from the cement laden water;

· Storing the treated water;

· Reusing the re-circulated water for further washing down (using the onboard treated water pump and high pressure hose line).


The system provides automated carbon dioxide pH adjustment of the washwater, adjusting its pH level from highly alkaline (circa. pH 13) to neutral (circa. pH 6 - 8) within the limits set by the Environment Agency.

Compared to using strong acids, carbon dioxide reduction of high pH water is intrinsically safe, as it is virtually impossible to lower the pH below 6, the lower consent level set by the Environment Agency. From a convenience point of view, bottled CO2 is readily available from numerous industrial gas suppliers across the country, with unused or partially spent carbon dioxide cylinders able to be returned to the supplier.

Reducing the pH of wash water using Siltbuster’s proven carbon dioxide dosing system is not only intrinsically safe for the environment, but also for the operator washing down plant. Strong acids do not need to be handled or stored on site and clean, treated and neutral pH water is used for washing, thereby avoiding the risk of the operator suffering chemical burns normally associated with concrete washwater.

With the low level reception area readily approachable from three sides of the unit, opening tailgate, drop down sides and large reception area, Big pHil offers real flexibility on site making it ideally suited for inner city with tower crane concrete skips, as well as larger scale projects and concrete pours. Access to the handrailed platform area on top of the treatment unit provides the operator with an elevated platform from which to wash the top and inside of the plant in a controlled secure area.

“Feedback from contractors about RCW units for concrete mixer truck chute washout has been great, but it is clear that other, often larger, concreting plant need the same treatment. It became apparent that a larger unit was called for and coupled with the issue, late last year, of the Environment Agency’s regulatory position statement on concrete washwaters on construction sites, Big pHil was born”, says Richard Coulton, Siltbuster’s managing director.

“We’re pleased to continue to help the construction industry meet their regulatory requirements and support the UK Concrete Show so we’re delighted to be revealing Big pHil at the show and look forward to wetting the big baby’s head across the UK!”