Cured-In-Place Pipe technology: Rehabilitating sewers without digging

Running below the surface of Europe is a dense network of underground transportation routes and utilities pipelines. Here, a fortune is buried, and by far the largest single item is the sewer systems. In Germany alone, the total length of the public sewer network amounts to around 594,000 kilometers (this is almost 37 times the distance between Berlin and Sydney!), which is valued at over 330 billion euros. This makes it all the more important for cities, local authorities and municipalities to take good care of this vital infrastructure asset. Leaking sewers and pipes do not only pollute the soil and groundwater, but can also lead to considerable costs for repairing and renovating the pipes.

Finding the right rehabilitation method has a major influence on the costs of repairing the sewer system and infrastructure. While for decades the standard remedial measure was to lay new sewer pipes when damage occurred, which meant significant costs and disruption, the preservation of existing pipes and the associated extensive pipe renovation has become increasingly important for some time. Pipe lining methods, also called cured-in-place-pipe (CIPP) method - are being used more and more frequently for the rehabilitation of underground sewer pipes to reduce costs and to support more sustainable practices. With CIPP, sewer pipes that are difficult to reach or replace can be rehabilitated without having to dig up the ground. With this innovative technology, a liner tube, which is impregnated with a liquid resin is inserted into an existing pipe. For the resin to harden a curing agent is needed and the curing process creates a "pipe within a pipe." At the end of the process, the lining acts as a new, corrosion-resistant pipe that is just as strong or even stronger than the original one.

As this process eliminates the need for time-consuming ground excavation work, pipe lining saves a great deal of time, money and disruption for cities, municipalities and local authorities. In view of the ageing sewer networks across the globe and the growing need for investment, it can be assumed that this renovation method will continue to play an important role in the future - especially as the trenchless rehabilitation method also helps to protect the environment: Due to much lower energy consumption when using the CIPP method (no need for heavy machinery), the CO₂ emissions generated during renovation are significantly lower than those when digging up the ground to expose the entire pipe.

Evonik already offers a broad portfolio of epoxy hardeners that show excellent performance and allow for fast curing even in challenging environments. To further improve the curing in pipe lining process, Evonik`s Crosslinkers business line has developed a new curing agent Ancamine® 2917, which is particularly suited for CIPP applications. This innovative curing agent is characterized by a good balance of pot life and long latency, which allows for impregnation in the factory, while traditional epoxy systems need to be applied at the job site leading to more flexibility and lower costs. Additionally, its  low viscosity enhances the fabric wetting, minimizing material waste and improving overall throughput. In short: Due to its excellent adhesion, good mechanical properties and very long pot life, Ancamine® 2917 increases the quality and efficiency while at the same time reduces the cost for CIPP installation. Therefore Ancamine® 2917 is highly recommended for use in cured-in-place-pipe application worldwide.
 

Crosslinkers - Creating Marketable and Intelligent Solutions

Mechanical strength, durability, chemical resistance and excellent color stability and adhesion properties – Evonik´s business line Crosslinkers offers tailor-made solutions for customers all over the world. As a raw material supplier, we have a profound understanding of the needs of our customers and their unique markets. Our range of products and expertise generates added value in a number of areas: from coatings and adhesives to civil engineering, high-performance elastomers and composites.

Ancamine® 2917 is developed for use in pipe lining systems to increase the quality and efficiency while reducing costs and disruption at the same time.