Crude Palm Oil Washing
Crude Palm Oil (CPO) washing is a critical pre-refining step designed to enhance oil quality by removing water-soluble impurities, trace metals, and residual contaminants. At Desmet, we offer innovative and efficient CPO washing technologies that ensure cleaner feedstock for downstream refining processes.
During the high-temperature refining of vegetable oils, particularly palm oil, undesirable compounds such as 3-MCPD (3-monochloropropane-1,2-diol) and GE (glycidyl esters) can form. These substances have raised significant health concerns, especially for infants and young children, who may be exposed through products like infant formula.
Scientific studies have shown that:
- 3-MCPD may cause kidney damage and negatively affect male reproductive organs in animal studies.
- GE has been found to be genotoxic and carcinogenic in rodent studies.
To mitigate the formation of the 3-MCPD during refining, it is essential to remove their precursors, particularly chloride compounds, from the crude palm oil. Targeting a chloride content below 2 ppm in the washed oil is a critical step in this process.
One of the most effective methods for achieving this is CPO washing - a vital pretreatment step that removes impurities and significantly improves the oil’s clarity and purity.
How does CPO washing work?
CPO washing is a simple yet highly effective method for reducing chloride content in crude palm oil. This process plays a crucial role in minimizing the formation of harmful contaminants such as 3-MCPD during refining.
In this process, crude palm oil is mixed with heated, chloride-free wash water in a retention tank. Typically, 7–10% wash water is used relative to the oil volume. This allows inorganic chloride ions to migrate from the oil phase into the water phase.
After sufficient mixing and retention time, the oil-water mixture undergoes phase separation. The result is washed crude palm oil with significantly lower chloride content, making it safer and more suitable for downstream refining.
This washing step can be integrated either at the palm oil mill or within the refinery, depending on the processing setup and desired product quality – even in small-scale operations.
Full process
The following flow chart illustrates Desmet’s optimized process for washing Crude Palm Oil (CPO), ensuring the removal of impurities and preparation for efficient refining.
Key advantages
High oil recovery
Minimal maintenance needs
Efficient phase separation
Optimized energy use
Compact, easy installation
Raw materials
Crude Palm Oil (CPO) feedstock varies widely in quality depending on its origin, processing methods, and storage conditions, which directly impact the efficiency of the washing process. Desmet’s technology is designed to handle diverse CPO profiles, ensuring effective impurity removal and consistent preparation for downstream refining.
Palm oil
References
Desmet CPO washing plants have been in successful operation since 2017, with capacities ranging from 300 TPD to 3,000 TPD. These installations demonstrate the versatility and scalability of the technology - proven across various plant sizes and operational setups.
