modified starch prodction line modified starch machine modified starch extruder
Here are the steps to make modified starch using a twin - screw extruder: ### 1. Raw material preparation - **Select raw starch**: Common types of raw starches used include corn starch, potato starch, tapioca starch, etc. Ensure the starch is of high purity and free from contaminants. - **Add reaction agents**: - **Cross - linking agents**: For cross - linked modified starches, agents like sodium trimetaphosphate (STMP), phosphorus oxychloride (POCl), or adipic acid di - vinyl ester can be used. The amount of the cross - linking agent is usually a small percentage (e.g., 0.1 - 5% by weight of the starch) depending on the degree of cross - linking required. - **Esterifying agents**: If making esterified starches, substances such as acetic anhydride for acetylated starches or octenyl succinic anhydride (OSA) for octenyl succinic anhydride - modified starches are added. The dosage of the esterifying agent is determined according to the desired degree of substitution. - **Other additives**: Catalysts may be required to accelerate the reaction. For example, sodium hydroxide can be used as a catalyst in some reactions. Also, pH - adjusting agents may be added to control the reaction environment. ### 2. Mixing the ingredients - **Dry mixing**: Thoroughly mix the raw starch and the dry reaction agents (such as cross - linking agents and catalysts in powder form) in a dry blender. This ensures an even distribution of the agents throughout the starch. - **Wetting and pre - treatment (if necessary)**: Some reactions may require the addition of a small amount of water to activate the reaction agents or to improve the homogeneity of the mixture. The moisture content of the mixture is carefully controlled, usually in the range of 10 - 30% depending on the specific reaction. ### 3. Twin - screw extruder setup - **Temperature settings**: - **Feed zone**: Set the temperature relatively low, around 30 - 50°C, to ensure smooth feeding of the starch - agent mixture into the extruder without premature reaction. - **Compression and mixing zones**: As the materials move through these zones, the temperature gradually increases. Temperatures in these zones can range from 50 - 100°C. The heat helps to start the interaction between the starch and the reaction agents. - **Reaction zone**: The temperature in this zone is crucial for the modification reaction. For cross - linking reactions, temperatures can range from 100 - 150°C, while for esterification reactions, temperatures may be set between 80 - 130°C. The high temperature in this zone accelerates the chemical reaction between the starch and the reaction agents. - **Cooling zone (optional)**: At the end of the extruder, a cooling zone can be set to quickly cool down the modified starch product. This helps to stop the reaction and prevent further degradation or unwanted side reactions. The temperature in the cooling zone can be set around 40 - 60°C. - **Screw speed**: Adjust the screw speed according to the viscosity of the mixture and the reaction requirements. A screw speed of 100 - 300 revolutions per minute (RPM) is commonly used. A slower speed (100 - 150 RPM) allows for better mixing and a more controlled reaction, while a faster speed (200 - 300 RPM) can increase the production rate but may require more careful control of the reaction conditions. ### 4. Extrusion process - **Feeding the mixture**: Feed the prepared starch - agent mixture into the hopper of the twin - screw extruder. The twin - screws rotate, conveying the mixture through the barrel. The screws also apply shear and pressure, which not only mix the ingredients more thoroughly but also help to expose the starch molecules to the reaction agents. - **Reaction during extrusion**: As the mixture moves through the reaction zone of the extruder, the chemical reaction between the starch and the reaction agents takes place. The combination of heat, shear, and pressure in the extruder promotes the modification of the starch structure. For example, in cross - linking reactions, covalent bonds are formed between starch molecules, changing the starch's physical and chemical properties. - **Extrusion and shaping**: The modified starch is extruded through a die at the end of the extruder. The die can be designed to produce the modified starch in the form of pellets or granules, which are convenient for further processing or storage. ### 5. Post - extrusion processing - **Drying**: If the modified starch has a relatively high moisture content after extrusion, it needs to be dried. Use a drying oven or a fluid - bed dryer to reduce the moisture content to an appropriate level, usually below 10%. The drying temperature can be set around 60 - 80°C. - **Milling and screening**: After drying, the modified starch may be milled to the desired particle size. Then, it is screened to remove any oversized or undersized particles, ensuring a uniform product. - **Quality control**: - **Degree of modification analysis**: Use techniques such as swelling power measurement, solubility analysis, and viscosity testing to determine the degree of modification. For example, for cross - linked starches, the degree of cross - linking can be estimated by measuring the reduction in swelling power compared to the native starch. - **Purity and impurity testing**: Check for the presence of any unreacted agents or by - products. High - performance liquid chromatography (HPLC) or other analytical methods can be used to detect and quantify impurities. - **Physical property evaluation**: Evaluate the physical properties of the modified starch, such as color, odor, and flowability. The modified starch should meet the required quality standards for its intended applications. ### 6. Packaging - Once the modified starch has passed all the quality control tests, it is packaged in appropriate containers. Common packaging materials include plastic bags, paper bags, or drums, depending on the quantity and end - use requirements. The packaging should be airtight to prevent moisture absorption and maintain the quality of the modified starch during storage and transportation
| Model |
Installed Power |
Production Capacity |
Dimension |
| TSE65 |
77KW |
100KG/H-150KG/H |
19000*1300*2200mm |
| TSE70 |
108KW |
200KG/H-250KG/H |
21000*1300*2200mm |
| TSE85 |
120KW |
300KG/H-500KG/H |
30000*1500*2600mm |
| TSE90 |
150KW |
500KG/H-1000KG/H |
32000*1500*2600mm |
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