MATERIALS & PRODUCTS FOR THE WASTE WATER INDUSTRY & WATER TREATMENT FACILITIES
Foul and surface water treatment involves rigorous processes requiring harsh chemicals. This creates aggressive environments and potentially destructive conditions where the physical infrastructure is subjected to chemical attack. For new infrastructure projects, only materials that can resist these conditions should be specified. Over time, surfaces become eroded, metal corrodes, sealants and mortars disappear from joints, all requiring repair.
Sewer repairs, Sewer tanking, Pipe joints & benching, Cess pit repairs, Cess pit tanking, Setting holding down bolts for waste water treatment machinery, Setting fixing bolts for access ladders in sewers and treatment plants, can act as a chemically resistant bedding mortar for blocks stones and bricks.
Natcem 35 can be applied underwater for repairing concrete or grouting and can remain permanently immersed in water. It is highly chemically resistant and resistant to sulphated water. CWG Grout can also be used underwater and can be used to plug live flowing leaks through structures as well.
Waterproofing for primary and secondary sedimentation tanks, retentions pools and chemical effluent is reuired to prevent pollution of surrounding subsoil and groundwater through leaks. See the surface protection systems below. Tanking mortars and slurries to prevent water percolation into or out of structures include SikaTop-Seal 107, SikaTop-Seal 250 Mitgrating, Natcem35, Natcem Tank, Sikalastic-1k, Sika Igolflex-200.
Sikaflex Pro 3 is a high-performance sealant that has excellent chemical resistance ideal for aggressive environments such as sewage and waste water treatment plants. It can be used on tunnel floor joints. Nitoseal MS600 is resistant to aerobic and anaerobic bacteriological attack, has good chemical and excellent water resistance, it is also used extensively in the water industry. Nitoseal PU12 is also a biodegradation resistant sealant with excellent adhesion under immersed conditions, suitable for joint sealing in sewerage treatment works, sludge digestion tanks, filtration and aeration tanks. Uniseal 170 is a high performance water industry sealant for contraction and expansion joints in waste water treatment structures.
The water tightness of concrete can be increased using a superplasticiser in conjunction with a water resisting admixture to limit its porosity. Chemical resistance can be improved through good concrete design and planning. Surface protection systems can also be applied to the concrete.
PVC and swellable hydrophilic waterstops can be used to waterproof internal and external construction and expansion joints in concrete structures such as tanks. Chemically resistant sealants can be used in conjunction with waterbar on the joint area at the surface faces of the concrete. See waterstops & waterbar
Renderoc repair mortar can be used to repair concrete in aggressive environments and as a protective lining coating for concrete structures such as settlement tanks. Other repair products include Nitomortar epoxy resin mortars, Pumaintain, SikaTop, SikaMonoTop, Resupatch, Natcem 35, Resufil.
Nitocoat protective coating can be used on settlement tanks. Also, protective coatings like Polyurea WPE, Sikagard®-63 N or Sikalastic-8800 can protect concrete from concentrated chemicals. Resuthane TG69 polyurethane screed can be used on bunds, floors and walls to protect the underlying structure from chemical attack. It is important to check the proposed/existing chemical composition and concentrations in contact with the surface to ensure the correct product specification is made. Sikalastic liquid membranes, Nitoproof 1000, Sikaguard epoxy coatings and Profex, Sikaplan FPO sheets can all be used to waterproof and protect structures.
CWG Grout can be used for repairing sewers, ground stabilisation and grouting around tunnel linings. It is suitable for situations where pollution and chemical attack is likely. Grout 105 can be used in the Utilities and Water industry for applications like repairs around sewers, min. order 5 tonnes. Conbextra grout may also be used in the waste water industry. Natcem D is a chemically resistant waterproof grout that can be used for grouting purposes in the Water and Utilities industries.
Where existing joint sealants have failed there maybe opportunities for leaks to penetrate through the gaps and pollute surrounding soil and groundwater. This situation can be repaired using a Sikadur-Combiflex or Expoband tape and adhesive solution across the joint without having to remove the failed joint material, saving time and labour costs. It can be used in biological tanks, primary and secondary settlement tanks, filtration beds, digestion tanks, grit / fat and grease chamber, and screening channels.
The dry spray Shotcrete sprayed concrete range can be used in cold, wet conditions and will set underwater. These fast setting, high early strength gain concrete repair materials are environmentally friendly, resistant to chloride and have excellent resistance to agressive chemicals and pollution. They can all be used in the Water and Utilities industries, and specific grades are available for use in potable water situations.