Corzan - PVC-C for Critical Applications in the Chemical Industry

Paul Boughton

Handling, storage and processing of corrosive or abrasive liquids and gases is a day-to day challenge for the engineers in the chemical processing industry.

Engineers are confronted with a wide choice of materials of construction ranging from standalone thermoplastics, glass fiber reinforced plastic (FRP) and dual laminate constructions with the thermoplastic (PVC, PVC-C, PE, PP) and/or fluoropolymer linings (ECTFE, PVDF, FEP, PFA).

Corzan™ PVC-C Industrial Systems are able to withstand harsch chemicals at higher temperatures (upto 93°C) in a variety of industries, such as chemical processing, metal treatment, chlor-alkali, pulp & paper, etc. and consist of piping systems, duct pipe, sheet and lining material.

Corzan®  PVC-C as a lining material is gaining more and more recognition, acceptance in contact with harsh chemicals and acids (H2SO4, HCl etc) due to the balance of properties, including excellent thermoforming, welding and lamination capabilities.

Dual laminate technology is one of the preferred solutions for demanding chemical applications, where the combination of superior chemical resistance of thermoplastics with the mechanical strength of FRP offers higher safety levels. Of course, engineers must consider resin formulation, glass and synthetic material selection, corrosion barriers and other features unique to composites.

Corzan®  PVC-C / FRP lined pipes are manufactured and installed in contact with aggressive products such as chlorine gas, hydrochloric acid, sodium hypochlorite and caustic soda for projects worldwide.

Corzan®  PVC-C sheet has excellent chemical resistance against highly corrosive acids, liquids and gases, in addition to extremely smooth surface, good electrical and thermal insulation properties, high impact strength; owing to this Corzan®  is the material of choice for engineers in the chlorine industry, electroplating, galvanizing  industries for different storage tanks, vessels, scrubbers etc.

Safety, chemical resistance and mechanical strength come at a price; however, the added cost of dual laminate construction is offset by longer service life, lower maintenance costs and higher process productivity.

Through a network of qualified Corzan®  PVC-C fabricators, Lubrizol AME offers cost-effective corrosion-resistant solutions for a variety of demanding applications in the chemical processing area. (Please check the list of qualified Corzan®  PVC-C fabricating companies with Lubrizol).

Most of fabricating companies have very high quality standards and from the start up of the project, conduct rigorous quality testing on composite samples to meet quality assurance standards for their fabricated products; certified laminators and thermoplastic welders have regular trainings, in addition to the annual testing and inspections performed by well-known organizations such as TUV, DVS in order to ensure high quality of fabricated products (piping, storage tanks and vessels).

Corzan®  PVC-C offers advantages over other plastic lining materials, such as PVC (higher temperature resistance), PVDF (no backing material required and better fabrication properties).

In addition to lower thermal expansion coefficient, Corzan®  PVC-C sheet has some fabrication advantages over PP sheet: in case of the tank diameter more than 1800 mm, the bottom of the tank in PP has to be built in tangerine sections and welded together; this results in more critical areas. This length of PP cannot be vacuum formed, whereas PVC-C can be vacuum formed. Thus PP would be more expensive and have more risk for leaks with the excess welds.

The choice of the bonding resin depends on the final application and there are a number of different vinyl or epoxy resins used with PVC-C.

Contact:

Sinikka Freidhof

Lubrizol Advanced Materials Europe BVBA

Chaussee de Wavre 1945

B-1160 Brussels

Tel: +32-2- 678-19-11

Fax: + 32-2-678-20-01

www.corzancpvc.com
 

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