Extraction Equipment

Pressurised Liquid Extraction

Pressurised Liquid Extraction (PLE), also known as accelerated solvent extraction, uses a liquid solvent at elevated temperature under enough pressure to keep it liquid above its normal boiling point. The heat and pressure are understood to speed mass transfer and dissolve target compounds faster, which is why the technique is considered for shorter cycles and lower solvent volumes than conventional soaking or reflux. It works with water, ethanol, hydro-alcoholic blends and other process-grade solvents. Mechotech’s company profile lists pressurised liquid extraction among its extraction methods, and Mechotech engineers turnkey PLE systems configured to each feedstock, solvent and target compound. PLE is treated as a candidate route: its suitability and performance for a given raw material are established in pilot trials, not assumed.

Pressurised Liquid Extraction holds a solvent above its atmospheric boiling point while pressure keeps it in the liquid phase. Higher temperature lowers solvent viscosity and surface tension and weakens the interaction between the target compounds and the matrix, so extraction can be faster, with solvent use and cycle time reduced compared with maceration or Soxhlet extraction on suitable feedstocks. Selectivity can be adjusted through the choice of solvent, its polarity and the operating temperature. Mechotech builds the extraction cells, heaters, high-pressure pumps and solvent-handling circuit with SS 316L product-contact parts, to a hygienic design with integrated solvent recovery and PLC/SCADA control. Temperature, pressure, flow, hold time and cycle are set during process development and pilot validation for each feedstock; because the technique combines pressure, heat and flammable solvents, pressure-equipment and hazardous-area scope are confirmed per project.

Technical Specifications

Technology	Pressurised Liquid Extraction (PLE) / Accelerated Solvent Extraction (ASE)
Working Principle	A liquid solvent is held above its atmospheric boiling point under pressure; the heat and pressure are understood to accelerate mass transfer and dissolution
Operating Temperature	Configurable, above the chosen solvent’s boiling point; set during process development
Operating Pressure	Configurable, set to keep the solvent liquid at the operating temperature; pressure rating specified per project
Solvent	Water, ethanol, hydro-alcoholic blends and other process-grade solvents, as agreed for the feedstock
Operating Modes	Static and dynamic flow-through (configurable)
Product-contact Material	SS 316L (SS 304 for structural and non-contact areas)
Automation	PLC/SCADA (configurable) with temperature, pressure, flow and purge control and batch logging
Safety	Pressure protection and interlocks specified for flammable solvents; hazardous-area scope and certification confirmed per project
Solvent Recovery	Evaporation and recovery circuit for solvent reuse (configurable)
Capacity	Configured to process requirement, pilot to commercial
Utilities	Steam / thermic fluid or electric heating, cooling water, nitrogen / inert gas, power, compressed air (project-specific)
Compliance	GMP hygienic design; full documentation for qualification
Final Output	Liquid extract; optional concentrate or dried powder via downstream recovery and drying

Plant Capacities

Scale	Typical Duty	Configuration
Pilot	Process development, feedstock screening and parameter validation	Small extraction cell with heater, pump and control panel
Semi-Commercial	Scale-up trials and contract manufacturing	Cell or vessel volume, heating duty and pressure rating configured between pilot and commercial scale
Commercial	Production runs on a confirmed feedstock	Cell volume, heating duty, pressure rating and recovery duty configured to the confirmed throughput

Cell volume, heating duty, pressure rating, solvent-handling and recovery capacity and cycle time are configured to the feedstock, solvent and throughput; a pilot trial is recommended to validate temperature, pressure and time before scaling.

Manufacturing Process

Feed Loading

Sized botanical material is loaded into the extraction cell or vessel and sealed; uniform particle size promotes even solvent penetration.

Solvent Fill & Pressurisation

The selected solvent is pumped into the cell and pressure is raised to keep it liquid at the target temperature.

Heating

The cell is heated to the chosen operating temperature above the solvent’s normal boiling point; the temperature is set during process development for the feedstock and target.

Static / Dynamic Extraction

The pressurised hot solvent contacts the matrix in a static hold or a continuous flow-through mode, and the target compounds dissolve into the solvent.

Extract Flush & Collection

Fresh solvent flushes the loaded extract from the cell into a collection vessel.

Purge & Depressurisation

An inert-gas purge clears residual solvent from the cell and the system is depressurised safely.

Solvent Recovery & Concentration

The extract is routed to evaporation where solvent is recovered for reuse and the product is concentrated.

Finishing & Drying

The concentrate can be dried to powder by spray or vacuum drying downstream, and the system is flushed for the next batch.

Major Plant Equipment

Extraction cell(s) or vessel(s) rated for the operating pressure
Heater (steam / thermic fluid or electric)
High-pressure solvent pump
Solvent storage and handling circuit
Collection vessel
Inert-gas (nitrogen) purge system
Solvent recovery evaporator and condenser
Pressure protection and interlocks
PLC/SCADA control panel

Plant Output

Liquid extractConcentrate or dried powder, via downstream recovery and drying (optional)

Applications

Nutraceutical and botanical actives
Phytochemicals including alkaloids, polyphenols, flavonoids, glycosides, OPC and organic acids (the classes Mechotech’s company profile lists)
Essential oils, oleoresins and natural colours, where the route proves suitable in trials
Standardised extracts for pharmaceutical, food and cosmetic use
Pilot studies and process scale-up

Key Features

Heat and Pressure Together
Holding the solvent liquid above its boiling point under pressure is understood to speed extraction; the benefit for a feedstock is measured in pilot trials.
Solvent Selectivity
Water, ethanol and hydro-alcoholic blends can be matched to the target, and polarity and temperature together tune what is extracted.
Integrated Solvent Recovery
A recovery circuit returns solvent for reuse and concentrates the extract.
Hygienic SS 316L Build
Product-contact parts in SS 316L with a smooth, CIP-friendly design and documentation to support qualification.
PLC/SCADA Control and Interlocks
Temperature, pressure, flow and purge are controlled from the panel, with interlocks suited to solvent handling specified per project.

Frequently Asked Questions

What is Pressurised Liquid Extraction?

Pressurised Liquid Extraction, also called accelerated solvent extraction, is a technique that uses an ordinary liquid solvent at elevated temperature while pressure keeps it liquid above its normal boiling point. The heat and pressure are understood to speed up extraction, which is why it is considered for shorter cycles and lower solvent use than traditional soaking or reflux methods.

How does pressurised liquid extraction work?

The extraction cell is filled with solvent and pressurised so the solvent stays liquid, then heated above its atmospheric boiling point. The heat lowers solvent viscosity and weakens the interaction between target compounds and the matrix, so the compounds dissolve. Fresh solvent then flushes the loaded extract to collection, an inert-gas purge recovers residual solvent, and the system depressurises.

How does PLE compare with conventional extraction?

PLE is considered for faster extraction and reduced solvent volumes than maceration, percolation or Soxhlet-type extraction on suitable feedstocks. Mechotech does not quote yield, time or solvent-saving figures for PLE: they depend on the raw material, the target compound and the solvent, and are measured in pilot trials. Heat-sensitive targets need particular attention.

What can a pressurised liquid extraction plant process?

It is a candidate route for botanical solids whose targets dissolve in water, ethanol or hydro-alcoholic solvents, including the phytochemical classes Mechotech lists: alkaloids, polyphenols, flavonoids, glycosides, OPC and organic acids. Suitability for oleoresins, natural colours and aromatic compounds is confirmed by trials on the actual material.

How is PLE assessed for a new raw material?

Mechotech treats PLE as a screening route that needs pilot validation. The recommended step is a small trial on the actual feedstock, measuring recovery, selectivity, solvent duty, product quality and cleaning, before temperature, pressure and hold time are fixed for the plant. Feedstock moisture and assay, the target purity and grade, and the solvent limits are the starting inputs.

What capacity is available?

Mechotech configures capacity to the process requirement, from pilot and R&D units to commercial-scale plants. Cell or vessel volume, heating duty, pressure rating, solvent-handling and recovery capacity and cycle time are sized around the feedstock, solvent, throughput and finished-product specification, with a pilot recommended to validate parameters before scale-up.

What material of construction and safety scope applies?

Product-contact components are SS 316L, with SS 304 for structural and non-contact areas, finished to a smooth, CIP-friendly hygienic standard under GMP hygienic design principles, with documentation to support qualification. Because PLE combines pressure, heat and flammable solvents, the pressure rating, interlocks, hazardous-area scope and certification are confirmed per project.

How does PLE differ from other Mechotech extraction routes?

PLE holds a solvent liquid above its boiling point under pressure. Subcritical Water Extraction (SWE) uses pressurised hot water, Microwave-Assisted Extraction and Ultrasound-Assisted Extraction use other energy inputs, and Hydro Alcoholic-Based Extraction and Alcohol-Based Extraction describe the solvent options. The right route depends on the raw material and target and is confirmed by trials. The hub is Extraction Equipment Plants.

Does Mechotech provide turnkey design, manufacture, installation and commissioning?

Yes. Mechotech designs and fabricates the complete pressurised liquid extraction system, including the extraction cells, heaters, high-pressure pumps, solvent-recovery circuit and PLC/SCADA automation, and installs and commissions it as a single turnkey plant, with support through scale-up and process validation.

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Pressurised Liquid Extraction