Industrial Microwave Units
From the laboratory to industrial scale equipment
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Plant extraction

Process choice

According to your specifications (plant and extracts), the association of a process and a solvent is designed to optimize the extraction efficiency.

Several parameters can influence the selection of process :

  • Plant : type, fresh or dry, whole plant or cut or powdered

  • Type, processing temperature limit, concentration…


The work done by PAT company (Plant Advanced Technology - Nancy) confirms the IDCO processes efficiency and show that the extraction yield of targeted molecule depends on the process and plant type


 Training

IDCO and REUS provide training on microwave and ultrasound eco-extraction techniques in partnership with UESS (Fragrances and Flavours European Union) and PASS cluster.

 

 



Ecoextraction

Essential oils, pure floral water (BIO),…

High efficiency, Very fast, Solventless, Pure extracts

In a microwave field, volatile molecules (essential oils) are taken away by vaporized plant water molecules.
These
vapors are condensed and oil is separated (decantation)

 


The end of extraction, the plant appears completely dried. This residue can be reduced to pellets and recovered as fuel.

 

Dried residue


pellets

 
The difficulty of this process is not to burn the plant. IDCO mixing technology make it possible
  • Cohobage (floral water reinjection) optimizes the extraction rate by delaying the drying of the plant
  • Too little moisture in the plant may require additional supply of water
 
 to avoid oidation reaction, it may be necessary to work without oxygen :
  • under nitrogen
  • under vacuum : it lowers vaporization temperature (150mb/ 70°C) and improves extract quality
 

Extraction in appropriated solvent

Flavoring oils, oil extraction

 

High efficiency, Very fast, Selective heating, High concentration

If ecoextraction (solventless) is effective on many plants, some molecules require the use of a solvent to be extracted. Microwaves enable to significantly increase the rate and the speed of the extraction when solvent is appropriated (that is to say, it has a low permittivity and doesn’t heat in a microwave field ).

 


Low permittivity solvent is « radioparent » for microwave, which heats selectively only the plant.

Additional options:

  • Cold extraction by cooling the mixture (solvent / plant) to optimize quality of extracts

  • Mixed microwave and ultrasound extraction to optimize rate and type of extraction



Solvent recirculation in thin layer

High efficiency,, Very fast, Any type of solvent, Concentrated extract, Little solvent, Quality of extract

When the extraction requires to use an unappropriated solvent for microwave, or to reduce its quantity, IDCO process involves flowing the solvent on the plant in a closed circuit so that it forms a thin layer thereon.

Microwaves then pass through the thin layer of solvent to heat selectively plant cells.



The solvent can be cooled when recycled to prevent heating by the action of microwaves. Extraction is so cold that optimizes the quality of the extracts.





Fresh solvent recycling

Operating Soxhlet kind
High efficiency, Concentrated extract, Little solvent

Ecoextraction process with vapor recycling

The plant is placed in a rotating perforated bowl which is in a tank whose double skins are cooled.

Microwaves allows vaporization of the floral water with a drive of molecules to be extracted. This vapor condenses on the walls of the tank and the water is vaporized again and circulates on the plant to continue the extraction and to optimize quickly the extraction rate.

Recyclage de solvant frais

The plant is placed in a rotating perforated bowl which is in a tank whose double skins are cooled. Some solvent is injected on the plant. According to the permittivity of the solvent and its vaporization temperature, microwaves allows evaporation thereof and the water component of the plant.

Extraction is then produced by the double action of the flow of liquid solvent on the plant and the passage of solvent vapor and water. The liquid solvent at the lowest point is enriched more and more in soluble extracts.

Extracts are recovered at the end of cycle : condensates + liquid phase



Mixed microwave and ultrasound

Extraction in liquid medium
High efficiency, Very fast, Concentrated extract, Quality of extract

This extraction requires the use of an appropriate solvent (low permittivity ε). Microwave and ultrasound may be applied at the same time.
The tank can be cooled to have a cold extraction, which allows to obtain a high-quality extracts.
Ultrasounds are used to destructure the plant matrix and microwaves to perform the extraction of molecules.
This double simultaneous action increases the extraction power of microwave.

The extraction rate and the number of extracted molecules are higher than those obtained by each process separately or alternately.

The solvent used may be the final medium (oil, mixture water/ethanol/glycerin,…)