Water Treatment Plant Aluminum roof

Advantage of Aluminum Material

  • Corrosion resistance
    Aluminum reacts with oxygen in the atmosphere to form an oxide film on the surface.
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  • Processability
    Easy and excellent processability such as extrusion, roll pressing, forging, and precise cutting process.
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  • Light weight
    The specific gravity is 2.7 g/cm3, which is only 1/3 of carbon steel (7.8 g/cm3)
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  • Recyclability
    Low melting point of 659℃ (carbon steel 1530℃) – easy to regenerate and save energy, economical materials
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  • Strength
    1/3 weight of carbon steel but has the yield strength as much as carbon steel (245 MPa)
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  • Non-Toxic
    Sanitarily harmless, odorless, eco-friendly – food and medicine industry,

Key Benefts

Economic feasibility
  • Automated factory production, ease of installation, reduce fabrication lead time à Reduce manufacturing and installation cost
  • Long lifespan and durability by 60+ years à Reduce maintenance costs
Maintenance
  • Corrosion resistance by oxide film à No maintenance needs
Durability
  • Great strength and Corrosion resistance
Heat reflectivity
  • Excellent heat reflectivity à maintain constant temperature inside the cover
Water plant industry
  • Excellent strength and durability ⇒ Suitable as a cover for water treatment facilities
  • Excellent corrosion resistance and air sealing à Excellent odor prevention effect (Excellent corrosion resistance to hydrogen sulfide (H2S), ammonia (NH3), mercaptan, etc.)
  • Good UV reflectance (approximately 2x steel) àpreventing paint peeling and fading of the roof surface
  • Excellent heat reflectivity ⇒ Maintains a certain temperature inside and provides optimal conditions for microbial growth in the tank
  • easy to modify and add parts/accessaries (suchas inspection hatch equipment, entrance, door, manhole, etc.)

Expected Lifespan of Aluminum Covers

Reference – AWWA D108-10(first edition)
Aluminum Dome Roofs for Water Storage Facilities(Page 9)

 

Comparision table

ITEM Aluminum SMC Membrane
Material
  • Aluminum alloys have excellent corrosion resistance to living sewage, wastewater, and industrial wastewater by quickly generating a protective oxide film as soon as it comes into contact with oxygen and stops oxidation
  • A safe structure designed and constructed in consideration of load conditions and safety rates such as fixed load, snow load, live load, wind load, etc
  • Manufactured by adding glass fiber to SMC (Sheet Molding Compound) unsaturated polyester resin, reinforcement, hardening agent, etc. and molding it with a high-temperature and high-pressure press
  • Durable Special Composites
    → Excellent chemical/heat resistance
  • SMC Panel and Aluminum Alloy Frame Configuration
  • Heat resistance / Flammability is somewhat low
  • A structural method using coated fabric as the main material, a structure that maintains its shape against external loads by giving it initial tension and increasing the rigidity of the exterior using a ductile membrane
  • The membrane structure material is commonly referred to as fluororesin, which refers to the application of Teflon to a plastic resin
Strength
  • Yield strength
    Panel : 145MPa
    Main frame : 245MPa
  • Yield strength
    113MPa
  • Ultimate strength
    40-70MPa
Specific gravity 2.7 1.6 – 2.0 1.0 – 1.5
Lifespan Longer than 40 years 10-15years 8-10years
Assembly time Great Normal Normal
Corrosion resistance Great Bad Bad
Air sealing Great Good Good
Maintenance Semi-permanent / almost no maintenance costs
No maintenance required because there is no corrosion caused by UV or harmful gases		 Periodic coating for UV protection is required. Maintenance and maintenance costs are required due to discoloration, deformation, and cracks Need to replace with short durability. Maintenance and maintenance costs are required due to discoloration, deformation, etc
Heat preservation High thermal barrier properties (5% thermal transmittance, 95% reflectance) Minimize temperature change in the reservoir due to external temperature Low thermal barrier
Sensitive to the outside temperature, temperature changes in the reservoir are severe, and a separate device is required to maintain the temperature		 Low thermal barrier
Sensitive to the outside temperature, temperature changes in the reservoir are severe, and a separate device is required to maintain the temperature
Simplicity Assembly structure: Various types of structural geodesic dome and rectangular type can be manufactured and installed according to shape Simple rectangular TYPE fabrication and installation only

  •  Geodesic dome structural form fabrication cannot be installed
  •  Somewhat less freedom in design
  •  Limited to specifications due to low dimensional processability due to plate-shaped manufacturing method
 When processing, it takes a long time to remove the adhesive part using a buffing machine and then perform high-frequency adhesion
Durability Great Good Bad
Eco friendly
  • Recycle materials after end of lifespan
  • Very low processing cost
  • It’s eco-friendly
 General waste after end of lifespan General waste after end of lifespan
Cost 100 80-90 60-70