Extraction is here defined as a solids/liquid extraction, where the liquid can be water or an organic solvent, e.g. alcohol. The liquid is passed through the solids that can be e.g. coffee or various health or herbs.
GEA Niro designs and supplies two types of extractor systems:
- Continuous Process – The CONTEX™ Link is a counter-current extractor, where the solids are transported by helicoidal screws placed in a tilted trough with heating panels. The extraction liquid (hot or cold) flows counter-currently down through the solids thereby absorbing the product media. The CONTEX™ extractor is typically used for coffee or herbs and health products.
- Batch Process – The batch process consists of a number of batteries or columns connected by pipes and a valve arrangement that makes this extractor work as a continuous extractor. The solids – typically ground coffee beans – are fed into the vertical placed columns, and the hot extraction liquid – water – flows downwards under pressure.