Brief Introduction
The native starch is natural product synthesis which is extracted and refined from cassava, potato, corn or wheat plant.Native starch with different properties can be applied to various fields. Sometimes the original starch does not directly put into use, for example, special treatment is needed because of starch insolubility, or special chemicals and ingredients shall be joined, then heating and stirring if unique flavor or appearance for food is needed. The starch whose property is altered is widely used in various fileds, such as industrial (like adhesives, textile mucilage) and food fields (used as sweetener like glucose / fructose or food additives for noodle soup).
- Procesing Flow.
Slurry preparation-Pretreatment- Reacting - Washing & Refining - Dewatering-Drying &Packaging
- Native Starch Slurry Preparation and Washing.
Native starch was initially purchased in small bags (25 to 50 kg) or large bags (1 ton), then stored in processing plant.
Mixing it with water, the dry starch will turn into starch milk with an concentration of 21Be(37% on dry basis). Meanwhile, the refined starch milk from native starch washing unit can also be directly used.
- Reacting Tank.
The refined starch milk will be pumped to a mixing/heating/ reacting tank and special ingredients (such as sugar producing enzymes), preparation (such as citric acid, vinegar (acetic acid)) and salt (such as sodium chloride) will also be added to the tank. Those additives was stored in a tank in a aqueous solution way, then will be pumped to blending tank. One formula is only suitable for producing one kind of product. The mixture was fully mixed and heated by hot water. This process must follow a certain time and temperature (25 to 50 ℃) curve. The mixture will be pumped to a buffer tank after neutralization and cooling.
- Refining.
The starch milk in buffer tank will be pumped to a sieve to get rid of impurities. After multistages hydrocyclone section, the salt, unreacted product or by-product will be removed. A small amount of starch in wastewater will be separated in effluent treatment pool.
- Dehydration & Drying.
Products now are very similiar to the final product, and only needs dehydration processing by scraper centrifuge.Durig dehydration, filtrate is released to the outside of filter tank. Since there is a small amount of starch in filtrate,so it needs to be pumped to first stage reclaiming hydro cyclone for further processing. Starch will be sent back to dehydration buffer tank and overflow will be returned to washing unit as cleaning water.
The dehydrated starch cake will be transfered to the inlet of flash dryer by conveying belt and entered into lifter by feeder The heating source of flash dryer is steam heat exchanger and the moisture in wet starch will be evaporated by then. After drying,starch will be seperated from air by cyclone separator, under which there is a air-seal apparatus. Moist air will be discharged into the atmosphere by deairing instrument. The collected starch will be pumped to vibrating screen unit for seperating refined starch from coarse particle by screw conveyor. Then the refined starch will be transported to starch storage room for storing and cooling, after which, it will be packed in 25 kg/ d by semi-automatic packer.
