Lanes Group’s Reline Division has carried out its first project to rehabilitate a pipe using a chemically-resistant UV liner.

Above: The relined pipe

A team from Lanes installed three UV liners, with a combined length of 200 metres, at a plant run by Solutia UK, part of Eastman Chemicals, in Newport, South Wales.

It was also the first time that Lanes Group’s supplier, Reline Europe – one of the world’s leading pipe relining technology companies – had supplied a UV liner to provide chemical resistance in the UK.

Solutia UK engineering manager David Davies said: “The lining solution identified by Lanes Group was ideal for us, given our production schedule and the limited window of opportunity we had to complete the project.”

Chemically-resistant pipe liners are usually installed using the hot cure in place pipe (CIPP) technique, where pressurised water is heated to nearly 100 degrees centigrade to harden the resin-impregnated liner. But there was not time for this method here.

Damian Tranter, business development manager for the Lanes Group Reline Division, worked with Reline Europe to develop a technically robust proposal for using UV relining technology, which would have a shorter installation time – and also be cheaper.

Solutia UK agreed to the proposal and also commissioned Lanes Group to rehabilitate and spray-line 10 manholes that service the pipeline.

Damian Tranter said: “The fact that this is a first for us and for our supplier reflects the rarity of using UV lining to rehabilitate pipes to provide chemical resilience.

“However, our success, and the benefits UV lining delivers, demonstrates how this is a viable pipe rehabilitation option for our other clients in the chemical processing industries.”

The 600mm diameter pipe being refurbished takes surface water from the site to a surface water holding tank before being pump to the onsite effluent treatment plant. The refurbishment was commissioned to ensure the structural integrity of the drainage system was sound and to eliminate the potential for any infiltration or exfiltration of contaminated water.

Lanes Group provided Solutia UK with detailed data, supplied by Reline Europe, to show the chemical resistance of the fibre glass liners and the specialist vinyl ester (VE) resin selected for the project.

Three liners impregnated with the resin were inserted end-to-end, one 104 metres long, the second 28 metres long and the other 97 metres. A UV light array was then sent through the pipe to cure the resin.

Damian Tranter said: “The UV light array was taken through the pipe at less than half normal speed, because the properties of the VE resin mean it takes longer for the light to penetrate the liner and cause the exothermic reaction needed for the curing process.

“Even with the extra time taken, each UV liner was installed during one 12-hour shift, whereas a hot cure liner would have taken at least 20 hours to install.”

A system of over-pumping, with 14 pumps, was needed to control water flows during the lining and manhole rehabilitation process, which was completed in 14 days, including weekend working.

With conventional hot cure lining, the water used to cure the liner becomes contaminated with styrene, and must be disposed of at an authorised waste site.