Lasers Used to Remove Bridge Residue
Cleaning company Adapt Laser recently completed a pilot project testing portable lasers to clean rust and lead-paint from a bridge in Southington, Connecticut, in an attempt to save time and money while reducing environmental waste.
A report from Equipment World states that the process, called laser ablation coating removal (LACR), was conducted by environmental cleanup company Best-Tec on an I-84 entry ramp from Mulberrry Street in the Plantsville neighborhood.
About the Test
The report states that the 1,000-watt handheld lasers worked by vaporizing paint and rust residue while sucking it into an extractor filter unit to protect workers.
The company adds that the highway bridge that the cleaning was performed on spans Canal Street and the Farmington Canal Heritage Trail, which did not have to be closed for work.
The cleaning project was reportedly estimated to take 15 days, though was completed in 14. This reportedly allowed for the Connecticut Department of Transportation to continue repairing corrosion damage to the ends of the 36-inch steel H beams with cast-in-place ultra-high-strength concrete.
The early completion also reportedly aided with compliance with the Occupational Safety and Hazard Administration and environmental regulations concerning possible lead paint exposure.
Adapt Laser states that the project’s completion helped verify the expectations of using the lasers in “remote working environments, with significant waste stream reduction, mitigation of emissions, small equipment laydown requirements, minimized lane closures and improved accessibility to tight spaces.”
A release from the company states the laser fume extractor has 3 stages of filtration. The first is reportedly made up of particle filters with a self-cleaning mechanism to maintain consistent performance, the next filter stage has activated carbon for gas, followed by a third stage HEPA filter.
The laser process reportedly accumulated around 40 pounds of dry powder waste in the lasers’ filtration system, significantly lower than the 9,000 to 12,000 pounds of potentially accumulated waste if the bridge had been sandblasted. Adapt Laser states that this is a reduction in waste of over 99%
The laser’s power supply can reportedly stay in the equipment trailer while the beam is produced by a fiber optic cable to a hand-held laser end effector. The system used on this project was reportedly equipped with two 150-foot-long fiber optic cables and two laser end effectors.
One end effector was reportedly designed for treating easy access areas while the other was designed to treat hard access areas.
Adapt Laser adds that some of the benefits of using laser ablation include:
Additionally, when compared to other surface prep methods, LACR with fume extraction on bridge projects can provide worker health and safety benefits, including reduced personal protective equipment (PPE) requirements, mitigating the exposure risks to harmful airborne substances and noise reduction.
Other Laser Surface Prep
In March, German research institute Laser Zentrum Hannover reportedly developed an environmentally friendly and efficient laser solution for biofouling. According to the release, laser radiation can be used to lethally damage marine fouling underwater without damaging the underlying coating of the ship's hull.
LZH scientists reportedly developed a process in which the cells of the fouling are damaged by laser radiation in such a way that the fouling dies and is then washed away by the water after some time.
The researchers conducted the study in the south harbor of Helgoland island, irradiating fouling samples with the laser. After two to four weeks, they returned them to the North Sea for investigation.
LZH reported that biofouling is a problem because of fuel consumption that leads to emissions, as well as introducing non-native species into foreign ecosystems.
Researchers explained that species displacement was a major risk for biofouling. For example, if a ship introduced foreign organisms into an ecosystem through hull fouling, it could have severely disrupted the ecosystem and led to ships being banned from docking in foreign ports.
Laser cleaning is a good alternative in this case, because the introduced biomass is lethally damaged during laser cleaning, rendering it is no longer dangerous for foreign ecosystems afterward.
The project was carried out alongside LZH by the Laserline GmbH, the Fraunhofer Institute for Manufacturing Technology and Advanced Materials IFAM. The project was funded by the Federal Ministry for Economic Affairs and Climate Action.