|Home||» Products||» Vietnam Calcium Carbonate||» Bleaching Clay|
- Minimum Order Quantity
- Unit of Measure
- 12500 INR
Bleaching involves the use of bleaching earths orclays. The term itself is misleading as colour removal is not the most important purpose of the bleaching process.
Vegetable oils contain contaminates that adversely affect the performance, appearance and taste of the oil. In order for it to be used in edible applications, the oil must meet high quality standard sthat require the removal of various impurities. It is used to decolorize purification in the field of animal and vegetable oil refining. It can take off the harmful pigments, phospholipids,cotton, acid, and so on in oil to make high-grade edible oil. And the decolorant of edible oil grade is widely applicable to all kinds of vegetable oils, animal oil and mineral oil, such as soybean oil, rapeseed oil, peanut oil, cottonseed oil, sunflower oil, palm oil, coconut oil, castor oil, camellia oil, corn germ oil, refined bran oil, sesame oil, safflower oil, and so on.
The bleaching process essentially removes some colour from the oil; reduces how much chlorophyll and carotinoids the oil contains; removes soap, gums and trace metals; and decomposes oxidation products.
Bleaching is performed prior to other processing steps such as hydrogenation, refining or deodorisation. Suppliers of the clays say that bleaching earth will account for 4-10% of overall refining costs, depending on a variety of factor sincluding oil type, dosage, oil contaminant levels, specification and disposal cost.
What are bleaching earths?
Oils are bleached using a powdered, surfactant material. Simply put, the powder is mixed with water, and then added to the oil where they absorb unwanted impurities before they are removed from the oil again, taking the impurities with them.
Bleaching earths are generally composed of up to three types of clay minerals: bentonite, attapulgite and sepiolite. The minerals act as absorbers with capacity being dependent on mineralogical structure and properties, such as surface area, particle size distribution, porosity and surface activity.
Bentonites are a soft stone with the capacity to absorb substances dissolved in water and other liquids. The minerals have been formed over time due to the natural adaptation of volcanic ash.
Dry bleaching vs wet bleaching
The two different methods utilising bleaching clays in the refining process are dry bleaching and wet bleaching. According to A lfa Laval, dry bleaching is the traditional method used for bleaching oils and fats. It is most common in Europe and Asia, but is used worldwide.
The process first involves heating the oil, the mixing it with bleaching earths or activated carbon (or a mix of both). This process takes place under vacuum which prevents oxidation and with as parging steam (the direct injection of steam in order to heat the oil with very high energy levels).
Because the bleaching takes place under vacuum of about 70 to , the humidity of the oil is greatly reduced.
Following the bleaching process, the powder is removed using pressure leaf filters and is collected in a buffer tank, which also operates under a vacuum.
Dry bleaching requires a much lower in itialin vestment than wet bleaching. The operating costs are also significantly less due to the use of plate heat exchangers,which require lower consumption of utilities. The process is also relatively easy and straightforward and requires only minimum space for set-up.
Wet bleaching, on the other hand, involves the addition of water in the process. Water makes bleaching earths work more efficiently, which means that less can be used, and oil losses are also reduced. Wet bleaching is attractive due to the lower costs of the process itself, even though start-up costs are higher. Water is added in the form of a citric acid solution, after the oil has been heated and before the bleaching earths are mixed in. The citric acid helps to bind trace metals and decompose residual soaps.
In the oil industry, it is used in the decolouration and purification of oil, lubricant oil, grease, paraffin oil, gas oil, kerosene and other minerals as well as petroleum cracking.
In the food industry, it can be used as agent forclarifying wine and sugar, fruit juice, beer stabilization treatment, glycosylated processing, and juice purification. It can save about 60% of the costs in sugarde colouration process. The colour of refined sugar, the content of reducing sugar, sulphite ions, chloride ion, protein calcium and magnesium ions, pH value and the temperature of the boil sugar have met current industry standards. Filter cakes can be mixed in the animal feed, reducing environmental pollution and utilizing resources comprehensively.
In the chemical industry, it is used as a catalyst, fillers,desiccants, adsorbents, and waste treatment flocculants.
- FOB Port
- Mundra / JNPT
- Supply Ability
- 1000 tons Per Month
- Delivery Time
- 15 Days
- Sample Available
- Sample Policy
- Free samples available with shipping and taxes paid by the buyer
- Main Export Market(s)
- Middle East, Western Europe, Australia, Asia
- Main Domestic Market
- All India