Some exothermic reactions require temperatures below 0° C to improve their performance and prevent secondary reactions
Often temperatures that need to be reached in the reactions and production speed are subject to the limitations of conventional coolants and heat transfer equipment. The use of liquid nitrogen or liquid carbon dioxide makes it possible to easily reach temperatures of down to –196°C, which isthe boiling point of liquid nitrogen.
To keep complete control over the reaction, Nippon Gases has developed several processes based on direct or indirect contact of the cryogenic fluid with the product to be cooled.
Any organic or inorganic fluid can be treated with the cooling systems developed by Nippon Gases, without substantially varying the design of the reactors or their working conditions
Cooling by direct contact
Conventional cooling methods are limited by the heat transfer surface or by the temperature of the cooling fluid.
To avoid these limitations, we can introduce liquid nitrogen or carbon dioxide as dry ice directly into the reactor. This takes maximum advantage of the frigories provided by either of these two products, producing drastic drops in temperature depending on the amount of nitrogen or carbon dioxide used. The temperature control system is also simple and effective. Different solenoid valves allow the cooling fluids to pass to the reactor based on the parameters set as limits (temperature, concentration, etc.).
If direct contact between the liquid nitrogen or the dry ice and the product to be cooled is inadvisable, it is possible to supply cooling through an external heat exchanger.
This system also allows reusing gases involved in another section of the production plant.