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| Retting methods | Description | Advantages | Disadvantages | Duration of retting |
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| Water retting | Plant stems need to be submerged in water and checked periodically | Produces retted fibres with great uniformity and high quality | Severe pollution issue arising from anaerobic bacterial fermentation, putrid odour, environmental problems, and high cost
Requires intense treatment on wastewater | 7–14 days |
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| Dew retting | The plant stems are spread evenly on fields to receive sufficient sunlight, atmospheric air, and dew for fungal colonisation and thereby breakdown cellular stem tissues and adhesive substances to release the single fibre | Pectin materials could easily be removed | Product contaminated with soil, restriction to certain climatic change, inconsistent quality, and reduced strength | 2-3 weeks |
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| Enzymatic retting | Enzymes hydrolyse gum and pectin material in the stem. Controllable retting conditions are allowed to maximise retting efficiency | Specific properties can be achieved for different applications by varying retting period and type of enzymes used
The process is cleaner and faster | Low fibre strength | 12–24 hours |
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| Chemical retting | Hydrogen peroxide, sodium benzoate, or sodium hydroxide is normally used in chemical retting | The smooth and clean surface can be obtained, inconsistency within a short period | Deterioration of fibre strength when the concentration of NaOH more than 1% is being used
High processing cost and unfavourable colour | 60–75 minutes |
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| Mechanical extraction | Force applied on the fed stem to separate fibres, then postcleaning, and further filter impurities | High quantities of the short fibre shall be yielded in a short period | Lower fibre quality and high cost | — |
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