Referece example / case study
CO2 compressors for supercritical compression to remove caffeine in tea
Starting position / boundary conditions
In the food, beverage and pharmaceutical industries CO2 is needed in various applications. One application is the removal of caffeine in coffee or tea by CO2. In this case, CO2 is used in the supercritical state, where it has properties as a solvent.
The end user in the reference example is a manufacturer of tea in China. The plant was equipped and designed by a German plant engineering company, which is the market leader in its field.
The CO2 is driven in a circulation process. After a recovery at pressure level 8 to 10 bar a compression to 50 till 60 bar takes place.
The customer operates various plant sizes. The delivery quantities are in the range of 10 to 200 Nm3/h.
The solution of HAUG includes different sized 1-stage compressors of SOG, TEG and TOG types, which are adapted to the size of the installation and are installed locally in the production.
The key arguments for HAUG were: high reliability, absolute oil-free, gas-tightness during operation or when stopped, process gas compressors individually tailored to the customer.
Examples of applications with oil-free CO2 compressors
- Application in the beverage industry to reduce CO2 enrichment
- Application in breweries
- Applications in the food and pharmaceutical industries as a solvent in a supercritical state over 60 bar. For example, for the removal of caffeine in tea or coffee.
- Application as a natural refrigerant with a heat pump. For this application are required relatively high pressures of more than 100 bar.
- Application for storing surplus electric energy in the form of natural gas, which is produced from carbon dioxide and hydrogen synthetically. The carbon dioxide may be originated for example from a biogas upgrading plant and the hydrogen from an electrolysis system. So by synthesis generated methane can be stored in the natural gas grid.
Technical advantages of the HAUG compressors
HAUG compressors have the best conditions for many CO2 applications thanks to their oil-free, dry-running and gas-tight design.
- no gas pollution by oil
- technically sealed, in operation or when stopped