CTA Tunnel Air Purification Solution

Aug 10th, 2023 | Charlene Zhang

Why we need tunnel air purification?

The vehicles driving in the tunnel emit a large amount of particulate matter, nitrogen oxide NOx, CO, HC and other pollutants, which will cause great safety risks to drivers and passengers in the tunnel, damage the health, and also cause great pollution to the environment surrounding the tunnel.

Tunnel air purification can help us:

● Protect the health of drivers and residents
● Protect the surrounding environment of the tunnel
● Reduce or eliminate the cost of shaft
● Reduce energy consumption
● Eliminate fire smoke

Normally people use high wind tower or exhaust well with multiple jet fan ventilation to do concentration dilution treatment of pollutants. This way of moving pollutants instead of processing pollutants, will cause pollutants eventually accumulate in the tunnel hole or settle around the wind tower, and usually needs a lot of civil engineering work to repair. It causes great damage to the surrounding ecological environment of the tunnel, and affects the health of the residents surrounding the tunnel.

Benefits Of CTA Tunnel Air Purification

CTA's Air Purification System uses high voltage electrostatic dust removal and renewable activated carbon gas adsorption technology, to collect and treat pollutants. It is equipped with wastewater recycling system which is an advanced technology that treat pollutants efficiently, it has no consumables, no secondary pollution. This system protects the internal and external environment, guarantee health of the drivers. The systems can also continue absorbing the fire smoke for about 30 minutes to ensure enough time for personnel escape.

Milestone cases

1989: Oslo Festning Tunnel, Norway, one of the world's earliest air purification tunnels
2001: Laerdal Tunnel, the world’s longest tunnel equipped with Air Purification System, 24.5 km
2001: Stromsas Tunnel, Norway, a large axial flow fan of a diameter of 6 meters long was deployed
2007: M30 tunnel, Madrid, Spain, large shaft air purification system, with a single-station air purification capacity up to 694 m3/s
2021: Central Kowloon Tunnel, Hong Kong, 9 APS stations, with an air purification volume of 2,250 m3/s

About CTA

Clean Tunnel Air International AS was founded in 1989, in Trondheim city of Norway. In 2012, CTA established Clean Tunnel Air China Co., Ltd. in Hong Kong to conduct business in China. In 2020, CTA joined AirQuality Group. For over 30 years CTA has been a world leader in the development and provision of air purification systems for road tunnels. CTA has finished more than 20 air purification stations in more than 10 tunnels. CTA is committed to the design, development, manufacturing and installation of Clean Tunnel Air Purification System.

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