Surfcleaner supports road tunnel construction

Surfcleaner supports one of the world’s longest road tunnel constructions. Due for completion in 2030, it will feature one of the world’s longest urban road tunnels, at 18km, just shorter than Tokyo’s Yamate Tunnel. The tunnels run under a lake, which is the metropolitan area’s most important water source, which means that the project is subject to clear requirements on how water may be handled during the construction of the tunnel. The construction companies working in the tunnels reuse cooling water for their drilling rigs, which must be cleaned of oil and other contaminants.

Surfcleaner system heavily reduces equipment costs at site

The drilling rigs work 24/7 under extreme conditions and can sometimes suffer breakdowns. Common causes of stoppages are hydraulic line breakage, causing hydraulic oil leaks. The contaminated water requires extra purification. Earlier, the cleaning was done using oil booms and absorbents followed by chemical treatment before it could be reused. If the water is not clean enough, it must be disposed to a municipal treatment plant for additional treatment and cannot be reused. The estimated cost of oil booms, absorbents and chemicals amounts to approximately €23,000 per year.

Surfcleaner Sales Director, says:

“We are using the world’s first surface separator to drive greater operational efficiency, energy and cost-savings.

Our Surfcleaner system offers a series of major benefits for tunnel construction projects, helping remove, separate and recover contaminants from water sources, including oil, diesel, petrol, and other pollutants. We installed three Surfcleaner SCO 1000 systems on the site – two in the tunnels and one at the purification stage to separate all the oil before the water reaches the purification system. In order to make the units as durable as possible, extra heavy-duty bearings were chosen for the machines to cope with the abrasive media.”

An increased amount of recirculated water

The installation of the Surfcleaner SCO 1000 provided more control over the water content and a guarantee that no oil was emitted to the internal purification stage, eliminating the risk of leaks to the surrounding environment. More cooling water could be recirculated minimizing the need to top up with raw water.

The purification process became more efficient after the oil was separated, which in turn means a cleaner pre-treated water, requiring fewer chemicals in the secondary treatment stage.

Since the Surfcleaner system collects all oil from the drill rigs, the on-site service technicians can focus on other duties instead of exchanging oil booms and absorbents on a daily basis. The installed Surfcleaner systems SCO 1000 minimize unexpected oil spills that potentially could result in steep fines for the contractor and contamination of Stockholm’s raw water intake.

Equipment: SCO 1000
Separation capacity: 1,000 l/h
Systems installed in 2021-2023: 3 unita
Application: tunnel construction