METHOD OF PRODUCTION OF DRY CO-EXTRACTS FROM PLANT MATERIALS AND APPARATUS FOR ITS IMPLEMENTATION Russian patent published in 2023 - IPC C11B9/00 C11B1/10 

FIELD: essential oil industry and food industry.

SUBSTANCE: method of obtaining dry CO₂-extracts, which involves the extraction of crushed plant materials with particle sizes of 0.5–8.0 mm with carbon dioxide (CO₂) in a subcritical state at a pressure of 10–15 MPa and a temperature of 10–30°C for 15–60 minutes or in a supercritical state CO₂ at a pressure of 15–40 MPa and a temperature of 40–50°C for 30–60 minutes; multiple circulation of carbon dioxide through a layer of crushed plant material, gas-liquid separation when separating carbon dioxide vapor from the liquid extract; compression of separated carbon dioxide vapors to a pressure of 15 MPa and their condensation at a temperature of minus 40°C during recuperative heat exchange with antifreeze cooled to a temperature of minus 45°C; heating of liquefied carbon dioxide to a temperature of 10–30°C or 40–50°C during recuperative heat exchange with water heated to a temperature of 55–60°C, with its return to extraction in a closed cycle mode; spray drying of the liquid extract with conditioned air with a moisture content of 0.005 kg/kg at a temperature of 55–60°C with obtaining a dry extract powder with a moisture content of 1.5–3.0% and an equivalent particle diameter of 0.3–2.0 mm; fine cleaning of exhaust air after spray drying to a dust fraction content of not more than 30 mg/m³, condensation of moisture from exhaust air at a temperature of minus 10°C through recuperative heat exchange with antifreeze; heating conditioned air to a temperature of 55–60°C with recuperative heat exchange with hot water at a temperature of 65–70°C and with subsequent return to the drying stage in closed cycle mode; the preparation of antifreeze is carried out by recuperative heat exchange with boiling water at a temperature of minus 50°C with propylene, and hot water is prepared through recuperative heat exchange with freon R113 with its condensation temperature of 75–80° C. The apparatus for implementing the method of production of dry CO₂-extracts includes the following: a two-column extractor with a variable operating mode of the columns: in the extraction mode and the waste raw material unloading mode; a gas-liquid separator for separating carbon dioxide vapor from the liquid extract; cascade three-stage heat pump, in the first stage condenser of which hot water is prepared, and in the third stage evaporator, antifreeze is prepared; a line for returning the separated carbon dioxide to the extractor columns, in which a gas tank, a two-stage compressor for compressing carbon dioxide vapor, a recuperative heat exchanger for condensing it, a reservoir for liquefied carbon dioxide, a fluid pump and a recuperative heat exchanger for heating the liquefied carbon dioxide are installed in series; spray dryer, water heater; fan supplying air to the spray dryer; a compressor for supplying liquid extract to the nozzles of the spray dryer; filter for fine purification of exhaust air from suspended particles; a two-section apparatus for condensing moisture from exhaust air, the sections of which include purified exhaust air, antifreeze and hot water with the possibility of redistributing flows and alternating operation of sections in condensation and regeneration modes; switches for the flow of exhaust air and antifreeze to the section of a two-section apparatus for moisture condensation, operating in condensation mode; antifreeze and condensate collectors; a flow distributor that supplies hot water to the section of the two-section apparatus for moisture condensation, operating in regeneration mode, and to the water heater for heating the air; a mixer of hot water with condensate installed in front of a recuperative heat exchanger for heating liquefied carbon dioxide, a mixer for combining waste water flows installed in front of the condenser of the first stage of a cascade three-stage heat pump.

EFFECT: invention allows to increase the yield of extractives.

2 cl, 2 dwg, 1 tbl