Waterproofing of Wastewater Sludge Tanks, Clarifiers, Pumping Stations, Sewers & Manholes

Gemite Cem-Kote systems have over 25 years of field-proven performance worldwide.

REQUEST A COPY

Gemite’s Cem-Kote Waterproofing systems can resist the strongest chemical attacks occurring in waste water structures due to MIC formed sulfuric acid, various flocculants, coagulants, sludge conditioners, neutralization and odour control agents and other chemicals used in treating waste water. It will provide also protection in storage of various chemicals, such as magnesium chloride, aluminum sulfate, active carbon and others. Protective systems are designed for Internal and External structural waterproofing of concrete.

Cem-Kote Cementitious Waterproofing Membranes are suitable for below and above grade, withstand Positive and Negative hydrostatic pressure exceeding 5 bar (50 m head of water) and are designed to provide lasting and reliable performance anywhere, under diverse climatic conditions.

Wastewater – Restoration

In restoration projects the concrete surface is seriously contaminated and deteriorated (eroded) to varying depth.  The condition of the surface is sometimes only found after a surface preparation, which is carried out by heavy sandblast.

Levelling & Reprofiling up to 12 mm (1/2”) – Gem-Plast TC

Spray applied and troweled, or hand applied.  Floor slabs may require a higher thickness.

Levelling & Reprofiling over 12 mm (1/2”) – Fibre-Patch OV

For larger volumes consider using Spray-Con WS ST – wet shotcrete process applied mortar.

Fibre-Prime – polymerised cementitious rustproofing is applied to any exposed reinforcing steel (rebar).

Clean reprofiled surface using 24 MPa (3,500 psi) pressure water, before application of waterproofing.

Wastewater – Chemical Protection & Waterproofing

System selection is based on exposure:

System #1 – “Open” structures (with H2S freely escaping)
CEM-KOTE FLEX ST

System #1 – “Open” structures (with H2S freely escaping)

1st coat          Cem-Kote Flex ST     Flexible Polymerised Cementitious Waterproofing

2nd coat        Cem-Kote Flex ST     Protects concrete against Sulfuric Acid

  Cem-Kote Flex ST is a 2-component, flexible, breathable, thixotropic, polymerised cementitious coating with high adhesion to concrete and properly prepared steel surfaces. Cem-Kote Flex ST is insensitive to moisture in the concrete and high relative humidity unlike polymer (epoxy & polyurethane) coatings. Cem-Kote Flex ST forms a seamless membrane - without joints & its inherent flexibility is enhanced with Reinforcing Fabric HD to deliver an excellent bridging of substrate cracks. Cem-Kote Flex ST forms a highly alkaline coating that protects concrete, or other substrate against attack by salts, and chemicals used in treatment of drinking water.

Application Procedures

    1. Concrete surface is cleaned and profiled using high-pressure water 34 MPa (5,000 psi)
    2. Cracks are repaired using Reinforcing Fabric HDembedded in Cem-Kote Flex ST
    3. Cem-Kote Flex ST is applied by spraying or brushing – 2 coat application is required Allow the 1st coat of Cem-Kote Flex ST to cure sufficiently to allow application of 2nd coat.
    4. Curing – 3-day air cure is sufficient prior to exposure to water
      1.  
System # 2 – “Closed” structures (H2S 20-50 ppm)
CEM-KOTE BARRIER COTE 100 + CEM-KOTE FLEX CR

System # 2 – “closed” structures (H2S 20-50 ppm)

1st coat     =          Cem-Kote Barrier Cote 100 - vapor retarder providing exceptional bond

2nd coat   =          Cem-Kote Flex CR - waterproofing + protection of concrete against sulfuric acid produced by MIC (Microbiologically Induced Corrosion)

 

Cem-Kote Barrier Cote 100

Cem-Kote Barrier Cote 100 delivers superior bond, even to contaminated concrete & provides super tough surface with high abrasion resistance. Cem-Kote Barrier Cote 100 is an excellent Vapor Retarder that reduces moisture transfer from below, plus is insensitive to moisture in the concrete and high relative humidity allowing application under conditions under which is impossible to apply polymer coatings.

Cem-Kote Flex CR

Cem-Kote Flex CR has an excellent chemical resistance to acids generated by Microbiologically Induced Corrosion (MCI) – it forms a seamless membrane (without joints) that provides lasting protection for concrete. Cem-Kote Flex CR is Non-toxic and much easier and safer to apply than polymer coatings. Its inherent flexibility is enhanced with Reinforcing Fabric HD to deliver an excellent bridging of substrate cracks.

Application Procedures

  1. Concrete surface is cleaned and profiled using high-pressure water 34 MPa (5,000 psi)
  2. Crack are repaired using Reinforcing Fabric HDembedded in Cem-Kote Barrier Cote 100
  3. Cem-Kote Barrier Cote 100 is applied by spraying or brushing
  4. Curing – 2-day air cure is sufficient prior to application of Cem-Kote Flex CR
  5. Clean the surface of Cem-Kote Barrier Cote 100 with high-pressure water 34 MPa (5,000 psi)
  6. Cem-Kote Flex CR is applied by spraying or brushing
  7. Curing – minimum 3-day air cure (under normal conditions) prior to exposure to sludge

Advantages of System #2

 

New Concrete

Cem-Kote Barrier Cote 100 can be applied after curing new concrete ONLY overnight

Polymer (epoxy or polyurethane) coatings require concrete to be cured for a minimum 28 days (most recommend 45 days) to prevent debonding. Installation of polymer coatings requires frequent testing to satisfy stringent surface “dryness” and very low humidity (35% relative humidity).

Insensitivity to Moisture & Humidity

Cem-Kote Barrier Cote 100 and Cem-Kote Flex CR can be applied on Wet Substrate & at High Humidity

Cem-Kote Barrier Cote 100 reduces moisture transfer value (MVT) to levels allowing application of epoxy coatings. Cem-Kote Flex CR is completely insensitive to surface moisture and high humidity. It stops water penetration from the Negative side and prevents debonding due to vapor condensation resulting in high capillary pressures at concrete-membrane interface. Polymer coatings are very sensitive to moisture in concrete, surface moisture, high relative humidity and water vapor penetrating from behind or below concrete (below grade).  Most polymer coatings require 1-inch depth of concrete to be dried, or application of moisture barrier layer, prior to application. These procedures are extremely expensive., since drying a concrete tank requires expensive heating for 2 weeks, or longer.

Excellent Resistance to Acid & other Chemicals

Best system for concrete structures exposed to sulfuric acid generated by MIC (micro-biological oxidation of hydrogen sulfide), such as wastewater treatment facilities (digesters, sludge tanks and clarifiers), sewer systems and manholes.

Breathability

Cem-Kote Flex CR is “breathable” = Allows Water Vapor to Escape from inside the Substrate

Polymer membranes act as vapor barriers, preventing water vapor escape - resulting in de-bonding problems.

Flexibility + Crack Bridging

Cem-Kote Flex CR delivers crack bridging, augmented by Reinforcing Fabric HD

Polymer coatings (epoxy, vinyl-esters or flexibilized epoxies) are non-flexible, without (or limited) crack bridging capability.

Easy + Fast Application

Cem-Kote Flex CR is Easily & Quickly Applied without Special Equipment

Polymer coatings are “sticky” and the tools and equipment is difficult to clean, even with expensive organic solvents.  Application of polymer coatings has to be carried out in a very narrow “application window”, which increase the applied cost.

Resilient

Cem-Kote Flex CR is a very “robust” product

It accommodates large variations in moisture content, relative humidity and temperature, and its “application window” is wide and tolerant to varying site conditions. Application of polymeric coatings is restricted due to the substrate moisture, RH and temperature conditions required. Expensive heating equipment is needed to dry the application area.

Eco-Friendly & Non-Toxic

Cem-Kote Flex CR is completely Non-Toxic & Not Hazardous

Cem-Kote Flex CR is a water-based, polymerised cementitious coating and does not require any personal protection.  Only disposable dust masks respirators are recommended during mixing. Polymer coatings are highly flammable, requiring proper ventilation at all times, and emit noxious smell requiring chemical protection (gloves & masks) at all times. Inhalation of epoxy fumes & dust is highly dangerous.

Cost Savings

Cem-Kote Flex CR is less than 50% of the Applied Cost of polymer coatings

Application of polymer coatings is very complex, especially when moisture and higher humidity exist, which significantly increases application time and results in very high applied cost.

System #3 - Heavy-Duty Chemical Protection
CEM-KOTE BARRIER COTE 100 + GEM-COTE EP 100

System #3 - Heavy-Duty Chemical Protection

1st + 2nd coat   =     Cem-Kote Barrier Cote 100 - vapor retarder providing exceptional bond

3rd & 4th coat  =     Gem-Cote EP 100 – high-level chemical protection

  Gem-Cote EP 100 delivers protection against attack by chemicals used in many areas of wastewater facilities (e.g. secondary containment structures for primary tanks holding corrosive chemicals). Cem-Kote Barrier Cote 100 is applied first to reduce MVT level sufficiently to assure continuous bond line between Gem-Cote EP 100 and the concrete surface and eliminate any possibility of epoxy coating debonding due to the high moisture vapor transfer from below, or within the slab.

Advantages of System # 3

 

New Concrete

Cem-Kote Barrier Cote 100 can be applied after curing new concrete ONLY overnight

Polymer (epoxy or polyurethane) coatings require concrete to be cured for a minimum 28 days (most recommend 45 days) to prevent debonding. Installation of polymer coatings requires frequent testing to satisfy stringent surface “dryness” and very low humidity (35% relative humidity).

Insensitivity to Moisture & Humidity

Cem-Kote Barrier Cote 100 can be applied on Wet Substrate & at High Humidity

Cem-Kote Barrier Cote 100 is completely insensitive to surface moisture and high humidity. It reduced moisture transfer value (MVT) to levels allowing application of epoxy coatings. Polymer coatings are very sensitive to moisture in concrete, surface moisture, high relative humidity and water vapor penetrating from behind or below concrete (below grade).  Most polymer coatings require 1-inch depth of concrete to be dried, or application of moisture barrier layer, prior to application. These procedures are extremely expensive., since drying a concrete tank requires expensive heating for 2 weeks, or longer.

Breathability

Cem-Kote Barrier Cote 100 is “breathable”, but acts as vapor retarder allowing safe application of “non-breathable” coatings in the second layer = Allows Water Vapor to Escape from inside the substrate

Polymer membranes act as vapor barriers, preventing water vapor escape - resulting in de-bonding problems.

Easy + Fast Application

Cem-Kote Barrier Cote 100 is Easily & Quickly Applied without Special Equipment

Polymer coatings are “sticky” and the tools and equipment is difficult to clean, even with expensive organic solvents.  Application of polymer coatings has to be carried out in a very narrow “application window”, which increase the applied cost.

Resilient

Cem-Kote Barrier Cote 100 is a very “robust” product.

It accommodates large variations in moisture content, relative humidity and temperature, and its “application window” is wide and tolerant to varying site conditions.   Application of polymeric coatings is restricted due to the substrate moisture, RH and temperature conditions required. Expensive heating equipment is needed to dry the application area.

Eco-Friendly & Non-Toxic

Cem-Kote Barrier Cote 100 is completely Non-Toxic & Not Hazardous

Cem-Kote Barrier Cote 100 is a water-based, polymerised cementitious coating and does not require any personal protection.  Only disposable dust masks respirators are recommended during mixing. Polymer coatings are highly flammable, requiring proper ventilation at all times, and emit noxious smell requiring chemical protection (gloves & masks) at all times. Inhalation of epoxy fumes & dust is highly dangerous.

Cost Savings

Applied Cost of System # 3 is substantially lower applied cost of polymer coatings

  Application of polymer coatings is very complex, especially when moisture and higher humidity exist, which significantly increases application time and results in very high applied cost.

Application Procedures

  1. Concrete surface is cleaned and profiled using high-pressure water 34 MPa (5,000 psi)
  2. Crack are repaired using Reinforcing Fabric HD embedded in Cem-Kote Barrier Cote 100
  3. 2 coats of Cem-Kote Barrier Cote 100 are applied by spraying or brushing
  4. Curing – 3-day air cure is sufficient prior to application of Gem-Cote EP 100
  5. Clean the surface of Gem-Cote EP 100 with pressure water 24 MPa (3,500 psi)
  6. Allow Cem-Kote Barrier Cote 100 to dry-0ut overnight, before applying Gem-Cote EP 100
  7. Apply 2 coats of Gem-Cote EP 100 to provide resistance to chemical attack

Sewers & Manholes – Restoration

In restoration projects the concrete surface is seriously contaminated and deteriorated (eroded) to varying depth.  The condition of the surface is sometimes only found after a surface preparation, which is carried out by heavy sandblast.

Levelling & Reprofiling up to 12 mm (1/2”) – Gem-Plast TC

Spray applied and troweled, or hand applied.  Floor reprofiling may require a higher thickness.

Levelling & Reprofiling over 12 mm (1/2”) – Fibre-Patch OV

For larger volumes consider using Spray-Con WS ST – wet shotcrete process applied mortar.

Fibre-Prime – polymerised cementitious rustproofing is applied to any exposed reinforcing steel (rebar).

Clean reprofiled surface using 24 MPa (3,500 psi) pressure water, before application of waterproofing.

Sewers & Manholes – Chemical Protection & Waterproofing

In underground (negative side) waterproofing it is essential that any “active” water leakage is stopped to allow application and cure time for the waterproofing coatings.

Fibre-Patch WP (water plug), or polyurethane injection, are used, usually prior to surface preparation.

System # 2 – H2S 20-50 ppm

1st coat     =       Cem-Kote Barrier Cote 100 – vapor retarder providing exceptional bond

2nd coat   =      Cem-Kote Flex CR – waterproofing + protection of concrete against sulfuric acid produced by MIC (Microbiologically Induced Corrosion)

Technological breakthrough for the municipal wastewater & manholes – Flexible, calcium aluminate cement polymer modified waterproofing coating, resistant to sulfuric acid, generated by MIC (Microbiologically Induced Corrosion) – micro-biological oxidation of hydrogen sulfide.

Cem-Kote Flex CR maintains a higher pH, making it more resistant to MIC, and provides long-lasting performance liner for moderate H2S exposure, such as manholes.

Application Procedures

  1. Concrete surface is cleaned and profiled using high-pressure water 34 MPa (5,000 psi)
  2. Crack are repaired using Reinforcing Fabric HD embedded in Cem-Kote Barrier Cote 100
  3. Cem-Kote Barrier Cote 100 is applied by spraying or brushing
  4. Curing – 2-day air cure is sufficient prior to application of Cem-Kote Flex CR
  5. Clean the surface of Cem-Kote Barrier Cote 100 with high-pressure water 34 MPa (5,000 psi)
  6. Cem-Kote Flex CR is applied by spraying or brushing
  7. Curing – minimum 3-day air cure (under normal conditions) prior to exposure to sludge