Freeze Concentration

TEC Square (together with Artisan Industries) has developed a freeze concentration alternative, that delivers the same level of quality at significantly lower investment- and operational costs. This concept, called “Low Impact Thermal Concentration”, has been proven in the field and so far exceeds expectations for high value food products.


Freeze Concentration Alternative

Low Impact Thermal Concentration


This Freeze Concentration Alternative uses low temperature (thus “low impact”) thermal concentration. Firstly the process uses a short-path Rototherm evaporator, keeping the product hold-up time very short, expressed in a couple of minutes. Secondly the Low Impact Thermal Concentration uses aroma recovery and aroma separation to enhance the taste profile exactly to the customer’s requirements.

Even though the process is officially called a thermal process, it is hardly possible to measure the impact of temperature on the product. Foremost, the process has low operational temperatures, due to the applied vacuum. Furthermore the technology of the evaporator design provides very quick processing conditions. As a result, the process has enormous advantages in start-up time, operational cost and flexibility. Together with a vastly reduced investment cost, this alternative to the traditional Freeze Concentration, proves to be a better or equal solution in all aspects.

The Low Impact Thermal Concentration technology consists of several sub-processes

Aroma recovery

FC - 3DThe heart of the aroma recovery system is the Artisan Evaporator/Stripper™. A stripping medium (steam, nitrogen or other) removes the aromatic components from the product flowing down the stripping column in a counter-current operation. Most important in comparison to competitive designs, the stripping column is self-draining. Therefore no product accumulation, thus limited fouling, can take place inside the column. Also the size and configuration is tailor-made for each application. The stripping operation normally takes place under atmospheric conditions, however vacuum could be applied as well. This will consequently reduce the impact on quality and taste.

Aroma separation

Next the aromatic components will be split into various fractions in a series of condensers. The design of the condensing system is very flexible, with the result that the split in aroma fractions can be easily adjusted to suit the required quality profile.

Evaporation

The stripped product continues to the Artisan Rototherm®-E Wiped Film Evaporator (WFE). The residence time in such an evaporator is very short (a couple of minutes). Furthermore the process is under vacuum, as such the set-point for evaporation temperature is low. This further reduces damage to the product. As a result, product with low dry matter contents, such as fruit juices and extracts, will be concentrated in a single pass to a very high end concentration. In reality end-concentrations of more than 60% are not uncommon. It is important to point out that this is possible with only minimal product losses.

Standardization

In order to enhance the taste profile further, it is possible to use the recuperated aromas selectively. Unwanted aromas can consequently be discarded, before the final mix takes place before aromas are mixed back into the concentrated product.

The advantages of Low Impact Thermal Concentration

The TEC Square developed “Low Impact Thermal Concentration” process has many advantages balanced against a typical freeze concentration plant.

  • Freeze Concentration

  • TEC Square Process

  • Falling Film Evap

  • Aroma Process
  • No aroma removal. All aromas stay thus at freezing temperature
  • Aroma recovery required before evaporation. Partial aroma recovery possible (removal of unwanted aromas)
  • Aroma removal required as a preparation before evaporation. Temperature typically atmospheric 100°C
  • Concentration
  • Crystallization and ice removal by scraping and heating
  • Low Impact Evaporation by Thin film Evaporation
  • Falling film evaporation process
  • Temperatures
  • Product at freezing temperatures
  • Aroma recovery and Evaporation at low temperatures (if vacuum is used).
  • High process temperatures because of multiple effect evaporation
  • Installation
  • Very high investment costs.
  • About 50% of the costs by comparison to an equivalent freeze concentration process
  • About 25% of the costs by comparison to an equivalent freeze concentration process
  • Energy costs
  • Very high demand, because of freezing and heating requirements
  • High demand on energy, because of the 1:1 steam ratio demand
  • Low demand on heating because of multiple effect evaporation
  • Residence time
  • 20-30 hours
  • 5-10 mins
  • 20-30 mins
  • Product quality
  • Very high
  • Very high
  • Lower quality, degradation due to time and temperature
  • Start-up time
  • 20-30 hours
  • 30 mins
  • 1 hour
  • Maximum TS
  • Normally 30-35% maximum
  • Typical 55-70% (no aroma), 50-65% (with aroma)
  • Typical 50-55% (no aroma), 46-50% (with aroma)
  • Production losses
  • Very little losses, only due to cleaning by water
  • Very little losses, only due to cleaning by water, especially no burn-on
  • Higher losses due to burn on
  • Cleaning
  • Almost none. Water rinse is normally sufficient
  • Water rinse is sufficient. Occasionally CIP after a prolonged run
  • CIP required every 24-48 hours

Standard Control System Package

FC - ControlAs shown above, the Low Impact Thermal Concentration process has a considerable amount of technology incorporated in the design. As a result, TEC Square has developed a proven control- and automation system for this process. Our standard supply comes with Allen Bradley PLC programming software, however Siemens options are available as well. Moreover we are flexible in the design of SCADA options. Our SCADA system features extensive monitoring possibilities coupled with easy control of all process parameters. TEC Square can provide this system as a stand-alone unit, but by the same token, we can incorporate this system into an existing process system as well.


For more information from Artisan Industries on wiped film evaporation please check the Artisan Website