The International Organisation for Standardisation (ISO) defines essential oils as volatile, aromatic liquids that are extracted from plants. The definition was adopted in 1968 at the ISO’s Technical Committee ISO/TC54 Essential Oils meeting in Lisbon.
Essential oil distillation is a method used to extract essential oils from plant materials. This process involves heating the plant matter with steam to release volatile compounds, which are then condensed into liquid form and collected. Essential oil distillation is essential for producing high-quality essential oils for various applications, including aromatherapy, cosmetics, and natural remedies.
Steam distillation is used to extract essential oils since they consist of numerous delicate compounds. Steam distillation allows the separation of the oils from plant matter in an effective manner as the steam helps break down plant cell walls, assists in removing the oils from the material and allows volatilisation to take place at lower temperatures than they normally would, also reducing the risk of decomposition or alteration of compounds
Definition
• Pure essential oils are complex mixtures of chemicals that are extracted from plants using steam distillation. • Essential oils have unique chemical compositions that affect their smell, absorption, and effects on the body.
Uses
• Essential oils are used in cosmetics, perfumes, food flavourings, medicine, and aromatherapy. • They have antimicrobial and antioxidant effects. • They have been reported to have strong anti-inflammatory potential. • Unique compounds of many oils have niche uses in various industries.
Extraction methods
• Essential oils are extracted from plants using steam distillation, water distillation, or mechanical processing of citrus rinds.
• Essential oils are soluble in most common organic solvents, including ethanol and diethyl ether.
Essential oils are volatile oils, generally odorous, which occur in certain plants or specified parts of plants, recovered by accepted procedures such that the nature and composition of the product is, as nearly as practicable, unchanged by such procedures.
“This is an important definition. It specifies clearly that the nature and composition of the oil must be unchanged by the process of extracting it and is therefore one reason why steam distillation is an appropriate method of extraction. Furthermore, because steam distillation has been the extraction method for most essential oils, the market accepts steam-distilled oil as normal oil.
Oil derived by another technique might be of slightly different chemical composition and therefore might not be accepted by the market.”
– Department of Trade and Industry Document South Africa Dec 2004
Components of an Essential Oil Distillation Process
Essential oils extraction is primarily achieved using specialised distillation equipment designed to carefully separate and capture the aromatic compounds found in various plant materials. This equipment operates through various techniques, each tailored to optimise the yield and quality of the essential oils derived from flowers, leaves, stems, roots and other botanical sources. By utilising distillation, producers can effectively harness the unique fragrances and therapeutic properties inherent in these natural substances.
1. Steam Generator or Boiler
The boiler or steam generator provides the necessary steam for the setup
The choice of fuel can differ based on the customer’s situation and preferences.
Over time, we have established relationships with various suppliers and can offer boilers at competitive prices or integrate with an existing steam source.
It’s important to know that boilers are classified as pressurised vessels under government regulations and must be regularly inspected. Typically, they are the main component that requires regular maintenance, that’s why we partner with local suppliers in your country and comply with relevant regulations for these pressure vessels. Refer to your government’s publications for these regulations.
If a steam generator is operated at atmospheric pressure, it is classified differently than regular boilers and is not subject to the same regulations. We have options for atmospheric steam generators for most fuel types.
Electric Boiler
We offer atmospheric or pressurised electric boilers. For optimal performance, electric boilers require a specific kind of water quality. Please send us your water quality test results.
These electric boilers are designed for easy cleaning, operation and maintenance.
Diesel or LP Gas
Diesel and gas boilers are subject to regulations and must be inspected by government authorities. They usually require passing an inspection at the time of installation. Additionally, they are more challenging to clean and maintain. Certain types of water cannot be processed by these boilers.
Wood/Coal or Bio Mass
These can be either manually fed or equipped with an automatic feed system, based on their size.
The steam heat supply can differ according to the amount of wood being used.
Regular cleaning is necessary.
Depending on their size and type (low pressure or high pressure), not all of these boilers need inspections.
2. Heat Exchanger
The heat exchanger turns steam and the volatile oil vapour back into liquid. Designed according to the machine’s steam flow rate and plant material oil properties.
3. Separator
The Separator separates the oil and hydrosol. Designed for the machine’s flow rate and oil properties of plant material used.
Separators are available for oils lighter and/or heavier than water.
4. Essential oil distillation stills
The still’s size is influenced by both the field capacity and the type of plant material. For instance, with lavender, there is a specific window for harvesting, so all the material must be quickly harvested and processed. This demands a larger machine size and a higher boiler steam flow rate, regardless of the field’s size, which differs from other plants with the same field capacity.
5. Coolers
If you don’t have access to plenty of cool water, you can recirculate the water using either an evaporative cooling tower or a dry one, depending on the local climate and cooling capacity.
Dry Cooler
This setup needs a pump and a water storage tank. The piping is often pre-installed, making it ready for use. It is highly efficient regarding water consumption, with minimal loss of cooling water.
Evaporative Cooling Tower
This option is typically better when the wet bulb temperature is lower. It requires a circulation pump and includes a reservoir inside the tower. These systems are designed for larger applications. Some water loss occurs due to evaporation.
6. Gantry or Lifting Equipment
To simplify your processes, we design gantries and lifting solutions that enhance production and efficiently handle biomass.
7. Conveyors
Feeding fresh material into elevated pots can be made more efficient with conveyors. We build conveyors for material feeding into the various unit configurations. These go well with tipping units as they are generally higher above the ground.