Alrox is a special process module designed for removing free, dispersed and/or dissolved air from a wide range of food products using vacuum deaeration.

Effective deaeration results in less oxidation of the product. This ensures better retention of important nutrients, such as vitamin C, as well as making sure the product has better flavour and colour stability. Other important benefits include less fouling in subsequent heat treatment operations, resulting in increased uptime. Removing air also improves the performance of subsequent homogenization processes.

How it works

The Alrox basic model works on the basis of hot deaeration.

Adding an optional Alfa Laval spinner distribution system makes it possible to work at lower temperatures, using cold deaeration. 

Hot deaeration

The incoming product, which is normally at a temperature around 40–60°C (102–140°F), is fed into a vacuum vessel via a distributing nozzle. The vacuum present inside this vessel corresponds to a boiling temperature that is 2–5°C (3.6-9.0°F) lower than the product inlet temperature.

The product expands into the vacuum. The release of pressure, and the resultant boiling, causes instant evaporation of some of the water in the product. This has the effect of stripping out any air that may be present, in whatever form.

The vacuum in the separator is maintained by a liquid ring vacuum pump. The deaerated product is discharged through the bottom outlet to an extraction pump that pumps the product out to the next processing step.

Cold deaeration

In the Alfa Laval spinner distribution system, which is optional equipment for the Alrox deaerator module, a special disc rotates at high speed, spreading the product in thin layers as it enters the vacuum vessel. This means the entrapped air is mechanically exposed to the vacuum with maximum efficiency.