Sugarcane is broadly classified into three varieties early, general and unapproved. Cane is sowed during February and October every year. The first seed growth is known as the plant and subsequent growth after harvesting from the stem is known as Ratoon. The early variety has more sugar content than the general variety.
Every farmer within the command area of the Mill is provided with a calendar, which tells him when he can expect a Mill Supply Ticket (Purchy), against which he will deliver the sugarcane.
He then harvests the cane and transports it either in a bullock cart or tractor trolley to the mill. Cane is also bought at the mill’s own centers within the command area. This cane is then transported in trucks or through rail to the mill.
Cane is weighed using an electronic weigh bridge and unloaded into cane carriers. It is then prepared for milling by knives and shredders. Sugarcane juice is then extracted by pressing the prepared cane through mills. Each mill consists of three rollers:
- Extracted juice mixed with water is weighed and sent to the boiling house for further processing. Residual bagasse is sent to boilers for use as fuel for steam generation
- This juice is heated and then treated with milk of lime and sulphur dioxide. The treated juice is then further heated and sent to clarifies for continuous settling. The settled mud is filtered by vacuum filters and filtered juice is returned to be further processed while the Oliver cake is sent out
- The clear juice is evaporated to a syrup stage, bleached by sulphur dioxide and then sent to vacuum pans for further concentration and sugar grain formation. Crystals are developed to a desired size and the crystallized mass is then dropped in the crystallizers to exhaust the mother liquor of its sugar as much as possible. This is then centrifuged for separating the crystals from molasses. The molasses is re-boiled for further crystallization
Thus, the original syrup is desugarised progressively (normally three times) till finally, a viscous liquid is obtained from which sugar can no longer be recovered economically. This liquid, which is called final molasses, is sent to the distillery for making alcohol.
The sugar thus is separated from molasses in the centrifuge is dried, bagged (50 Kg and 100 Kg), weighed and sent to storage houses.
Sugar is made in different sizes and accordingly classified into various grades I.E. large, medium and small.