Fighting corrosion with geopolymer

Corrosion is a problem that affects water and wastewater infrastructure throughout Australia, and proves an ongoing struggle for asset managers. Concrete pipes are being constantly exposed to harsh conditions that can cause significant downtime due to costly rehabilitation or maintenance works. Installing an appropriate coating, such as geopolymer, can rehabilitate and protect the asset from corrosion, extending its life and reducing long-term costs.

Geopolymer mortar is ideal for corrosion protection and increasing structural integrity of water and wastewater assets, offering superior tenacity and cohesion with minimal rebound and wastage. In the USA, geopolymer materials have been used in the wastewater industry for over 25 years, and it is standard practice to specify a geopolymer for structural pipe or culvert relining.

Product Manager for Hychem, Colin Murphy, is proud to announce its recent deal with Standard Cement Materials to distribute and manufacture under license in Australia its GeoCast with Reliner MSP Geopolymer Mortar.

“Standard Cement Materials is a leading cement manufacturer and construction materials distributor in the US and we’re excited to bring its GeoCast with Reliner MSP geopolymer technology to the Australian market,” Mr Murphy said.

“The GeoCast with Reliner MSP pipe renewal system complements our current range of sewer linings by expanding our catalogue into different markets and applications, including corrugated metal pipe, reinforced concrete pipe, brick pipe, large diameter pipe, steel culverts, tunnels and structural reinforcement.

“With over 20 years of proven successful installations and a design life of over 50 years, we believe the structural and flexural strength, permeability, ease of application, and fast curing attributes will translate well in the Australian market where utilities are searching for long-lasting and effective solutions.”

Why choose geopolymer?

Geopolymer is a unique formulation using special ingredients, including pozzolans, or microsilica that react with alkaline substances to enhance the chemical resistance and physical properties of the mortar. It is used to provide corrosion-resistant protection in high hydrogen sulphide environments, increase structural integrity, and stop the infiltration of groundwater in deteriorated structures.

It is also made predominantly of recycled materials which reduces the amount of greenhouse gases produced in manufacturing compared to calcium aluminate cement.

“As Australia moves towards reducing greenhouse gas emissions, this is an ideal choice and doesn’t compromise on the quality and durability of the product,” Mr Murphy said.

Expanding market offerings

GeoCast with Reliner MSP is made up of a blend of polymer modified mortar, a dry microsilica powder, polypropylene fibre and other selective admixtures, and is specifically designed for horizontal, vertical and overhead surface repairs in reinforced concrete and brick pipes, corrugated metal pipe inverts (CMP) and arches, sewer manholes, and water and wastewater structures.

Mr Murphy said one of its main features is its fast turnaround and structural capabilities.

“Asset downtime not only costs water utilities and asset owners a lot of money, it can also causes disruption to their customers and those living and working near the asset, so using a fast curing product is essential to having the asset up and running again in the shortest time possible,” Mr Murphy said.

The superior physical properties from geopolymer allow the material to be used as a standalone structural lining.  It can be cast in place in much less thickness than traditional cement based products like shotcrete, therefore pipe diameter is not drastically changed.

“GeoCast with Reliner MSP is designed for quick turnaround with an initial curing time of 4.5 hours and the asset can return to service within 18 hours. Accelerators can also be used to speed up this process.”

It can be installed by centrifugally casting or using an air atomising shotcrete nozzle to apply the geopolymer liner.

“Hychem can advise on the type of equipment required for installing GeoCast with Reliner MSP as equipment type can be customised for various project demands,” Mr Murphy said.

Other benefits of GeoCast with Reliner MSP include:

• Applications to 100mm thicknesses overhead
• Stops water infiltration in pipes, tunnels, manholes, wet wells, raw water filtration, bridges, dams, and treatment plant structures
• Adds long-term performance, tenacious bond and lower permeability
• Formulated with freeze thaw durability advantages on demand
• Provides higher compressive, flexural and tensile strength
• Protects against corrosion, [MIC] hydrogen sulfide gas (H2S), sulfates, salt water, chlorides, water vapor, grease and acids to pH 2.0 (ASTM C267)
• Unlike regular Portland cement, it does not corrode or attack the reinforcing steel

“GeoCast with Reliner MSP is an excellent addition to our catalogue. Asset owners are always looking for solutions that provide minimal downtime and substantially increase design life. We are committed to providing these solutions at Hychem, which is why we are excited to add such a versatile and high performing product to our range,” Mr Murphy said.

For more information on GeoCast with Reliner MSP call Hychem on (02) 4646 1660.