Rail trials bring ice blast leaf removal one step closer

Attached to the front edge of trains, the system works by firing dry ice pellets at supersonic speed at the railhead, freezing any leaves that have fallen and been compressed on the line. These frozen leaves are then blasted away as the dry ice pellets turn back into a gas. In development at Sheffield’s Department of Mechanical Engineering since 2021, the technology has recently been put through its paces on the Wensleydale Railway, in partnership with train operator Northern.

The dry ice technology being demonstrated at Wensleydale Railway

“This is a gamechanger for the industry – the next step in finding a solution to tricky autumn conditions,” said Rob Cummings, seasonal improvement manager at Northern.

“One of the biggest risks to our performance during October and November is 'leaves on the line', but by helping to develop new innovative technology we aim to deliver the very best service for our passengers.” 

Funding from Network Rail’s Performance Innovation Fund helped the researchers purchase two retired Pacer trains, based at Wensleydale Railway, to test the new design and develop a plan for the system to be fitted throughout Northern’s fleet next year.  

Fallen leaves on rail lines are currently cleaned using railhead treatment trains (RHTTs), but there are only a limited number of these trains available, so they can’t treat the whole of the network. The new ice blast system can potentially be attached to any train, making it more efficient and more cost effective than RHTTs, improving services across the country.  

“This is a great example of a university testing and proving an idea in a lab-based experiment and then scaling it up to be trialled and implemented in the field to make impact,” said Sheffield’s Professor Roger Lewis, the university’s lead on the project.

“This can only be done through good teamwork and having champions in the railway industry such as Rob and his team at Northern."