Applications

Other applications

Cryogenics

 

The experience of Guichon Valves in the design of cryogenic valves (-196°C) has been recognized worldwide for over 20 years. The company has developed and industrialized cryogenic sectioning equipment based on technologies of gate valves (models approved by Air Liquide), metal-seated butterfly valves, and ball valves. These equipments have various applications in the liquefied gas industry, as well as in fine chemicals and nuclear submarines.

 

 

 

Molten Salts

Guichon manufactures valves specially adapted to Molten salts

Gate valve (700) (702), Tank Bottom Valve (602) (607), Plug Valve (500) (503)

Critical valves – Best practices for CSP & MSR – Molten salts applications
Gate valve
Type: 700NDN 3/8″ to 36″ PN 10 to 250

– Welded construction

– Stainless steels or alloys
Tank bottom valve
Type: 603MDN 3/4″ to 16″ PN 10 to 150

– Cast construction

– Stainless steels and alloys

Manufacturing

  • Materials: Stainless Steel, Special Alloys
  • Construction method: Welded, Cast, Solid

Uses

  • Service conditions: High temperature, Low pressure
  • Types of fluids: Liquids, Slurry, High viscosity fluids

FAQ – Molten Salts

Molten Salts – Chemical formula:

– Hydroxides: NaOH, KOH, NaOH-KOH, etc…
– Nitrates: KNO3-NaNO2-NaNO3, etc…
– Carbonates: Na2CO3, K2CO3, Li2CO3-K2CO3, Na2CO3, etc…
– Fluorides: LiF-NaF-KF, etc…
– Chlorides: NaCl, KCl, CaCl2, Li-Cl-KCl, ZnCl2, etc…
– Etc…

Molten Salts – Uses of Molten Salts

– Salt baths for various thermal treatments of alloys: cyanide, chloride, and fluoride salts (cryolite)
– Production of reactive metals and refractory metals
– Heat transfer fluids and thermal storage (fluoride, chloride, and nitrate)

Molten Salts – Manufacturing process of Molten Salts

The molten salts technology includes a wide range of applications. The use of molten salts in industrial processes continues to grow, and these environments are gradually being accepted in the chemical industry. In thermal treatment techniques, molten salts are commonly used as a medium for heat treatment of metals and alloys, as well as for surface treatment. In nuclear energy and solar energy, they have been used as a heat transfer and thermal storage medium. Other applications include metal extraction and high-temperature batteries and fuel cells. All these technologies are linked to the general properties of molten salts:
– High heat transfer capacity
– Ability to reach very high temperatures (> 700°C)
– Electrical conductivity.
Molten salts have been used in many industries as high-temperature heat transfer fluids. Depending on the required temperature for a specific application, molten salts can be classified as shown in the table below:

Operating Temperature 150-250°C 250-400°C 450-1000°C
Molten Salt System Alkaline chlorides, aluminum chlorides Nitrates, nitrites, alkaline hydroxides Halides, sulfates, alkaline carbonates

The production of steam in solar thermal power plants is a good example of how molten salts can be used as heat transfer fluids (see the following figure):


Operating around atmospheric pressure reduces the mechanical stress experienced by the system, which simplifies the mechanical design aspects. The material in contact with the molten salt is sometimes subjected to corrosion. However, the corrosion rate is strongly dependent on the type of molten salt, operating temperature, and fluid velocity. Coatings may be required.

Molten Salts – Recommended valves

Guichon Valves offers custom valves based on long stems and graphite seals to ensure proper operation in molten salt environments and at very high temperatures.