Qdos and APEX pumps treat hydrodemolition water

Qdos and APEX pumps are providing the processing power behind EcoClear, a treatment system developed by Aquajet for filtering hydrodemolition water. EcoClear enables users to safely discharge blast water back into the environment or recycle it accordingly.

• EcoClear machines from Aquajet rely on WMFTG pump technology
• Chemical dosing provided by a trio of Qdos pumps
• Sludge handling provided by APEX hose pump

Hydrodemolition uses high-pressure water jetting for the removal or controlled demolition of concrete. The process is 100% free of vibration, which is not only good for the operator but the surrounding structure. However, it produces large quantities of waste water that must be treated for disposal or recycling.

Qdos and APEX pumps

Removing sludge

EcoClear treats the hydrodemolition water in different internal chambers, working with flocculation technology to remove the maximum amount of sludge from the water.

“We use a Qdos 30 to dose coagulant into the reaction tank, and a second Qdos 30 to pump neat flocculent to the reservoir, where it mixes with water to provide pre-activation,” explains Ronnie Hilmersson, Aquajet’s Research and Development Manager. “A third unit, a Qdos 60, pumps the mixed flocculent into the reaction tank. All of the pumps are controlled automatically.”

To ensure the correct dosage of chemicals, an automatic magnetic flowmeter is connected to the Qdos pumps to improve the settlement characteristics of suspended solids whenever chemicals are introduced to the reaction tanks. Optical turbidity sensors and pH probes continuously monitor and record water quality, ensuring that only clean water is discharged. If the water exceeds its required limit, the feed pump automatically shuts down to prevent dirty water from escaping.

To improve settlement characteristics, blast water is pumped into the inlet chamber and mixed with a flocculating agent. Carbon dioxide is automatically introduced via an internal diffuser, to create microbubbles that reduce the pH level of the blast water.

Lamella clarifier

Flocculated blast water passes through a lamella clarifier where the suspended solids settle, leaving solids-free water. This lamella clarifier is produced by Siltbuster and is where the primary function of EcoClear—the separation of water from sludge—takes place. The APEX hose pump is then used for pumping out the settled solid sludge from the storage hopper.

Clear water

EcoClear is marketed under the strapline ‘Clear water, clear conscience’, and it is easy to see why.

“In essence, dirty hydrodemolition water enters the machine, with clean water emerging at the other end where it can be discharged as groundwater or sewer water, or used as part of a closed-loop recycling process,” says Mr Hilmersson, who goes on to summarise the important role played by the WMFTG pumps in fulfilling this function.

“The pumps are maintenance-free and we’ve not had any issues in the field since EcoClear machines were launched. Qdos and APEX are good pumps and provide high levels of reliability, which is exactly what our customers need in this application.”

APEX hose pump

Qdos metering pump