Waterproofing tanks and pipes in sewage systems

Water treatment facilities like sewage treatment plants, sewers and shafts or sewage water tanks made from concrete or masonry are exposed to a variety of stresses. The restoration of such facilities entails waterproofing, concrete repair and concrete protection as well as protection against acids and abrasion. For this a wide range of materials are used.

KÖSTER Waterstop can be used to quickly waterproof small active leakages. The fast setting plug mortar swells slightly and closes the leakage instantly.

Areas with insufficient air circulation like sewer systems develop high concentrations of sulphur dioxide which leads to the creation of sulphuric acid on the surface of the construction members. Sulphuric acid is very aggressive, especially against concrete. KÖSTER NB 1 Grey can be used for waterproofing on the positive and the negative side. KÖSTER Silicate Mortar is used for protection against acids. As an alternative, acid resistant tiles can be used which are bonded to the substrate with KÖSTER Silicate Adhesive. The jointing is done with KÖSTER Silicate Mortar. In this manner an acid and abrasion resistant surface is achieved.

The standard waterproofing for masonry is KÖSTER NB 1 Grey. In case of active leakages the KÖSTER KD System is applied.

For restoring concrete or masonry damaged by acids, the substrate is to be mechanically cleaned until a solid, unburdened substrate is achieved. The substrate is then primed with KÖSTER Polysil TG 500. Reprofiling is done with KÖSTER Repair Mortar NC. On top of the reprofiling KÖSTER Silicate Mortar is applied as acid protection.

Shafts made from masonry and concrete must also be mechanically cleaned until a solid, unburdened substrate is achieved. Reprofiling and levelling is done with KÖSTER Sewer and Shaft Mortar, which has been especially developed for this field of application. It bonds very well to damp substrates, can be applied easily and sets quickly. KÖSTER Sewer and Shaft Mortar can to a certain degree even be applied under flowing water.

Pipe connections are often a source of leaks in sewer systems. Retroactive waterproofing is sometimes difficult due to significant water pressure from the inside and the outside. KÖSTER PUR Gel is an ideally suitable injection material for such cases. Together with the mix water and the surrounding soil it forms an elastic waterproofing layer around the leakage. In this way pipe connections or defective pipes can be sealed quickly and permanently.

Elastic waterproofing of cracks is achieved with KÖSTER 2 IN 1. The material is injected in two steps: First in order to stop the water from flowing and secondly to close the crack elastically and permanently. In case of strong water ingress KÖSTER IN 1 is used due to its faster reaction time. In order to seal the crack permanently the same crack has to be injected with the elastic resin KÖSTER IN 2 afterwards.

Always adhere to the specifications in the respective Technical Guidelines.

Waterproofing water tanks

Concrete water tanks are waterproofed from the inside using KÖSTER NB 1 Grey or KÖSTER NB 2 White. KÖSTER NB 1 Grey is approved for use in drinking water environments.

The waterproofing is applied onto solid and prepared concrete substrates. The primer KÖSTER Polysil TG 500 increases the mechanical resistance of concrete surfaces and immobilizes salts present in the substrate. Smaller areas are repaired with KÖSTER Betomor Multi A or KÖSTER Betomor Light 88. Larger areas can be restored and reprofiled with KÖSTER Repair Mortar NC.

In the case of below grade tanks, the external side is waterproofed with a crack bridging coating, for example KÖSTER Deuxan 2C.

For waterproofing as well as for concrete repair, KÖSTER Polysil TG 500 is used as a primer in order to harden the concrete and prepare the substrate for the repair mortar.

Always adhere to the specifications in the respective Technical Guidelines.