Sustainability
PE liners: adding decades to sewer manholes
Hydrogen sulphide turns into acid on concrete walls. A polyethylene liner keeps it away, and keeps the structure working far longer.
TopicSustainability
Published
Reading time1 min read
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In sewer networks, bacteria release hydrogen sulphide gas. On the damp upper walls of a manhole it is oxidised into sulphuric acid, which slowly eats into unprotected concrete.
How the liner works
A polyethylene liner is anchored into the concrete while it is cast, so it cannot peel away. The acid meets plastic instead of cement paste, and the concrete behind it keeps its full section and strength.
- Chemically resistant to the acids found in sewage
- Smooth surface that resists deposits and is easy to clean
- Anchored mechanically during casting, with no adhesive layer to fail
- Joints sealed with gaskets that match the liner
Less replacement, less waste
A structure that lasts longer is the most direct way to cut the material and carbon cost of a network. Fewer replacements also mean fewer excavations and road closures over the life of a city.
