The liquid nitrogen crusting machine is a device designed to crust and freeze solid, semi-dense and liquid products in the food, pharmaceutical and industrial sectors, thanks to the use of nitrogen in its liquid phase.

It can also be used as a pre-freezer, in support of gas or mechanical freezing tunnels.

Operation and technical specifications

The unit uses direct contact between the product and cryogenic fluid at very low temperatures inside a vibrating tank with linear movement, ensuring almost immediate freezing of the product surface. The cryogenic fluid consists of nitrogen, a non-toxic, inert and safe gas.

The frequency of the vibrators determines the speed at which the product advances and, consequently, the contact time with the liquid nitrogen (on average between 10 and 15 seconds).
This time can be adjusted by varying:

• The angle of movement of the tank
• The length of the tank
• The inclination of the plane

Key benefits

• Efficiency: the system is equipped with a collection tank and cryogenic pump for the reuse of liquid nitrogen until it is completely exhausted.
• Sustainability: fluid evaporation during freezing is managed by means of an extraction hood with a transfer fan, reducing dispersion into the environment.

Operating cycle

• Automatic filling of the process tank from the storage tank.
• Manual adjustment of parameters:
• Liquid nitrogen pump flow rate
• Inverter frequency of motor vibrators
• Tilting the tank using jacks
• Temperature adjustment of the unit with liquid nitrogen circulation only (10 minutes).
• Supply of the product to be coated.
• End of product supply.
• After 2 minutes: liquid nitrogen interruption.
• After 60 seconds: the unit switches off and the tank is drained.
• When reached room temperature: wash and clean.