Refined Edible oils are found in coconut, corn, cotton, olive, palm, nuts, soybeans, and sunflower. Furthermore, they contain gums and other impurities that are removed by reducing, weakening, and inserting candles. Let’s understand the process to refine them.
The basic premise of these processes can be summarized as follows:
Degumming: The first stage of the vegetable oil refining process
Motivation is the first stage of refining vegetable oil that begins with the heating of crude oil. The feed is placed in a degumming container where the oil temperature rises slightly. Besides, the oil weight is reduced by removing Phospholipids / Gums from the raw vegetable oils. There are usually two different types of phospholipids present in crude oil depending on hydration levels:
- Hydratable or Water Degumming
- Allergic or Acid Degumming
Neutralizing: Phase Two of the Vegetable Oil Refining Process
Neutrality or simply Neutralizing is the second step to refine the vegetable oil after finishing. In this process, the feedstock is transferred to Neutralizers where the ambient temperature is maintained at 55 C to 70 C depending on the quality of the crude oil. Further, the oil is constantly disturbed to maintain consistency.
The main purpose of energy reduction is to remove the Free Fatty Acids present in crude vegetable oils. In chemical refining, alkali is used to reduce FFA and to remove oil acidity.
The main purpose of the Neutrality Process is to replenish FFA with an alkaline solution and reduce the soaps in the water phase. In the edible oil industry, caustic soda is used in the treatment of FFA’s. Sometimes potassium hydroxide can also be used by other processors.
FFA is a stearic acid that breaks down into a triglyceride molecule leaving diglyceride in fats.
The free fatty acid is derived from the H + carboxyl group. This H + of the active stearic acid group reacts with the OH- caustic soda (NaOH) group to produce soap and water.
Tracking of non-glyceride contaminants is also removed by the neutralizing step. Some examples are as follows.
- Other Phospholipids
- Oxidized Products
- Steel Tools
- Colour Paintings (e.g. gossypol)
- Insoluble pollutants (e.g. fines
Bleaching: Phase Three of the Vegetable Oil Refining Process
The process of adding bleach is the third step to refine vegetable oil after the completion of the effective inactivity process. The Bleacher Pressure Container is used to perform the Bleaching process. Bleacher is a carefully designed machine based on structure parameters to ensure the perfect bleach strength of crude oil. Besides, this process has a massive significance.
The purpose of Bleaching is to remove pigments contained within Vegetable Oils. The finished oil is heated at an additional temperature by using thermic boilers to eventually increase the oil temperature to 120 C to 130 C. The oil is then treated with Bleaching Clays that advertise the colors. The added amount of clay for coloring varies depending on the oil. It also depends on the color content of the crude oil and the color indicator of the desired oil.
Oil processing includes a wide range of steps:
- The extracted oil can be stored in a container after mixing with a reagent to allow the emulsion to break down before passing into the separator.
- In the process of reducing the normal acid added by 0.1 – 1%. Phosphoric acid is widely used. Although, citric acid is suitable for other oils.
- The process temperature is usually in the range of 120 – 160ºF (50 – 70ºC).
- The temperature of the neutralization process can be higher, up to 200ºF (95ºC).
- The effectiveness of sodium hydroxide solution varies depending on the acid content and type of fat.
- During brush removal, it can be added to a filter such as diatomaceous earth to protect the finest clay particles from filters.
Consumption of edible oil is usually in high volume and has continuous performance. Repetitive additives are traditionally made using static shear mixers or in-line agitators, which can lead to many potential problems.
Acid and sodium hydroxide solutions form a small fraction of the total product and should be reduced to a very small droplet size to ensure the closest contact with the oil. Low shear devices with a short duration cannot easily achieve this. Due to the addition of clay, normal development cannot immediately produce different and distinct configurations. Additionally, the improper distribution of reagents reduces process efficiency, leading to chemical overgrowth and proliferation.
The Wahal Engineer High Shear compound can be used for additives of acid, sodium hydroxide, and clay. They can be easily installed instead of a static mixer or an inline agitator. The Wahal Engineers mixer can produce a good spread of reagents just by bypassing. This can be accomplished by performing the following steps.
The reagent was introduced into the oil shortly before the discovery of the Wahal Engineers mixture. The ingredients are pulled from the head of the rotor/stator function and mixed vigorously.
Centrifugal force pushes objects at the edges of the work surface where they are reduced to fine droplets/particles in the space between the wall particles and the inner wall of the stator.
A further reduction in the particle size follows when the mixture is forced out of the stator, increasing the surface area of the reagent exposed to the oil. This speeds up the reaction and increases the yield.
- The improved distribution of reagents in oil increases the area exposed to oil, accelerating reactions
- Reducing the use of chemicals and minimal environmental impact
- Quick processing times
- Swap working heads and screens allow the Wahal Engineers mixer to be modified to improve the performance of various oil processing
Wahal Engineers offers a wide range of suitable additives for acid and sodium hydroxide, as well as Flash mix for clay distribution:
- High Shear In-Line Mixers
- Aeration is free
- Easily restored to an existing plant
- Ready for ongoing processes
- Availability of ultra sanitary models
- Availability of multistage units, thus offering a high degree of cutting, resulting in refined particle size and faster processing times
- Wahal Engineer Flash Mix
- Designed for rapid dispersion of powders into liquids
- Reduced cleaning requirements
- Small operator input is required