Investigation of styrene release during relining

Lining with flexible lining is a method of renovating the inside of old end-of-life sewer pipes, storm water pipes and drinking water pipes that can no longer ensure a tight system. Lining with flexible material is done widely in real estate and in piping infrastructure. It is a sustainable solution to total pipe replacement and waste is greatly minimized. However, many formulations for lining waste water pipes still contain styrene.

Styrene is listed as a phase-out substance on Chemical Secretariat's SIN candidate list SIN List (chemsec.org). Therefore, it is important for Swedish VA industry to quantify the problem of government. The extent to which governance is a problem can be affected by several different circumstances. Styrene is  said to break down after a few 100 meters according to manufacturers, but it is important that this is verified. By understanding the context in which styrene poses a risk, the use of styrene-based products can be optimized for minimum risk to the environment and eventually replaced with styrene-free products.

This project involves taking water and material samples from the field and also doing testing with the water rigg located at RISE Kimab to investigate styrene release from the cured materials in a controlled environment.

This project will include:

1.Determine the speed of styrene degradation in a number of waste water samples,by adding known amounts of waste water and measuring (using GC-MS and established methods) how quickly it decomposes depending on pH and temperature. 

2. Carrying out measurements in connection with installations of the respective thermal and UV hardened flexible lining fields.

3.Quantifying how much styrene leaks in connection with the installation of a flexible feed dependency on various factors and methods (installation procedure, etc.)

4.Quantifying whether the use of formulations containing styrene poses a problem downstream from installations, for example in wastewater treatment plants.

5. Through lab tests of flexible feed in water rigs with well-defined conditions understand how different parameters affect leaching of styrene to water. 

6.Clarify alternative formulations, and evaluate pros and cons by comparing durability and performance of the different formulations available on the market.