Corn starch making machine
Corn starch making machine
1. Cleaning the corn
2. Steeping the corn in sulphurous acid liquid
3. Steepwater evaporation
4. Removing the germ of corn
5. Primary separation-A primary HP HC separator splits by centrifugal force the mill stream in two fractions:
• Gluten Overflow
• Starch Underflow
6. Starch refining
Washing with fresh clean water refines the crude starch milk. With hydrocyclones it is feasible to reduce fibre and solubles including soluble protein to low levels with a minimum of fresh water. To save water the wash is done counter currently, i.e. the incoming fresh water is used on the very last step and the overflow is reused for dilution on the previous step, and so on.
By using multi stage hydrocyclones all soluble materials and fine cell residues are removed in a water saving process. The refined starch milk contains an almost 100% pure starch slurred in pure water.
With a middling separator the overflow from the starch refining hydrocyclones may be refined into:
• Process water Overflow
• Starch Underflow
7. Centrifuges and hydrocyclones
he centrifuge obtains its gravitational force by spinning the bowl. The hydrocyclone has no moving parts and the separation is totally dependent on the pressure difference over the cyclone.
The technological development and quality demands have forced centrifuges to give way for hydrocyclones in corn starch refining, but centrifuges still hold a defensive position in gluten concentration.
Starch is among the most pure of all agricultural products. Actually, purity is the most important parameter in being competitive.
8.Starch dewatering
The purified starch milk is discharged to a peeler centrifuge for dewatering. The peeler filtrate is recycled to starch refining. The dewatered starch is batch-wise peeled of and discharged by gravity to the moist starch hopper.
9.Starch drying--The moisture of cornstarch after drying is normally 12-13 %.