Pipe rehabilitated with chemically-resistent UV liner

Louise Smyth

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

A team from the national pipe rehabilitation service, based in Manchester, 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.

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.

Damian Tranter, Business Development Manager for the Lanes Group Reline Division, was aware that Solutia UK needed the pipe rehabilitation work to be carried out within a narrow window of opportunity.

He worked with Reline Europe to develop a technically-robust proposal for using UV relining technology, which would have a shorter installation time, and would deliver a significant budget saving for the client.

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 just 28 meters 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.