Removing wax from oils improves edible oil transparency at low temperature, which enables effective packing of the oil into transparent bottles. Alfa Laval's systems for dewaxing process separate waxes and remove impurities containing wax—safely, reliably and effectively. Comprehensive dewaxing solutions from Alfa Laval help you cut refining costs, add revenues through oil recovery, and boost your refined edible oil yield.
Enhance oil clarity and yield by optimizing your dewaxing processes
- Increased operational reliability and efficiency
- Optimized dewaxing and filtration processes
- Maximum yield with minimal losses
- Straightforward operation with full automation and control
- Increased oil quality and stability
Dewaxing is critical to enhancing edible oil stability as well as preventing crystal formation and cloudiness at low temperatures. Getting the most out of crude sunflower, corn and cottonseed oils requires the right system optimized to your process requirements. Make sure you take into account factors such as feed oil quality, capacity, effluent conditions, desired refined oil quality. For stable refined oils that pass cold tests, you can trust time-tested Alfa Laval wet, dry and combination dewaxing systems. Whatever your dewaxing challenge, you can rely on Alfa Laval for comprehensive and reliable solutions, global service, local support and peace of mind.
Systems for dewaxing process of edible oil
Alfa Laval dewaxing systems effectively remove waxes from crude oils through physical refining processes using cold enzymatic degumming or cold chemical refining processes that combine wet dewaxing, such as multi-wax and combi-wax systems, with a dry dewaxing system.
Alfa Laval Cold Enzymatic Degumming system
This physical refining process uses two inline centrifugal separators and involves enzymatic degumming to agglomerate gums, followed by wax crystallization at low temperatures (dewaxing/winterization) to remove the waxes along with phosphatides precipitated from the oil by a separator. A second separator is used for oil washing to improve phosphatides reduction.
Alfa Laval Multi Wax system
This chemical refining process combines the high-efficiency neutralization refining techniques of the Alfa Laval Multi Mix process with subsequent oil cooling, wax crystallization, cold washing and wax removal with water. These techniques are similar to those developed by Alfa Laval for fractionating palm oil. Using three inline separators, this process results in a well-refined oil with reasonable losses for high free fatty acids containing oil.
Alfa Laval Combi Wax system
This chemical refining process combines wet dewaxing using two inline separators with cold neutralization and simultaneous wax crystallization, followed by wax and soapstock removal.
How it works
How the dewaxing process works
Wet dewaxing & Dry dewaxing
In most of the cases, it is important to note that wet dewaxing alone removes sufficient amounts of wax to achieve the oil stability required to pass the 24-hour cold test; this is based on average quality sunflower oil with the wax content 600 ppm. At the same time, wet dewaxing can process oil with wax content of up to 2000 ppm; however, this impacts the results of the cold test. Dry dewaxing also has its limitations, such as a maximum wax content of 900 ppm for the feedstock to pass the 24-hour cold test. To achieve effective wax removal, many edible oil producers now combine wet dewaxing and dry dewaxing processes in their refining plants. This combination enables oil producers to pass the 72-hour cold test.
The dry dewaxing process involves mixing the oil with filter aid powder, followed by cooling and maturation. Slow cooling ensures that any crystals formed do not prompt blockage of the filter. Dosing the filter aid powder acts as a control for seeding for crystal growth. Because phosphatides promote crystal growth, bleaching to remove these compounds takes place before the dry dewaxing process.
The filter aid powder is a consumable that cannot be reused, and the amount of filter aid is related to amount of wax in feed oil. The dosing ratio varies, and the amount of filter aid required can be up to 10 times the amount of wax. Spent filter aid contains up to 60% oil, making proper dosing of the filter aid powder key to process optimization.
The removal of wax and filter aid powder takes place in pressure leaf filters, which are automated and require minimal operator attention. Combined with PLC-supervised filter operation, a special oil cooling technique allows full filter utilization, which boosts the yield of processed oil.