The heat treatment system to be used depends on the properties of the product and the results to be achieved. Here TechQu offers solutions for all the different requirements.
Depending on your product and the desired shelf life, you can choose between various methods of heat treatment, like short time heating – high temperature (STHT), high temperature – short time (HTST), or ultra high temperature process (UHT) by means of indirect or direct heating.
Indirect heating uses a partition to separate the product from the heating (or cooling) medium, with the partition transferring the heat from the medium to the product, avoiding any direct contact between the two. Indirect heating is done with different kinds of heat exchangers, where the choice depends on different factors, such as the physical properties of the product, flow rate, run time and cleaning requirements.
- Plate heat exchangers (PHE) are mainly used for smooth, low viscous liquid products.
- Tubular heat exchangers (THE) can also handle products with particles up to a certain size and offer longer running times. The maximum size of particles depends on the diameter of the tube.
- Scraped-surface heat exchangers (SSHE) are specially designed for the heating and cooling of viscous, sticky and lumpy products, with or without particles.
Direct heating puts the product into direct contact with hot steam under strictly controlled conditions, rapidly reaching the target temperature. After holding for a certain time at the target temperature, the temperature is also lowered rapidly by flash cooling in a vacuum vessel. This rapid heating and cooling minimizes the heat-load, resulting in a high-quality product.
