Hot limed / Sulphited Juice Screening System
In a normal milling plant the feed juice temperature is much below 35 – 40 Deg C and hence the total Rotary juice screen assembly is of “open” feature, i.e. top and discharge end drums are open to atmosphere. However, considering the temperature of hot juice at 70 – 80 Deg C, it is essential to provide Rotary Screen with our unique feature of “totally enclosed” arrangement to avoid heat losses and to prevent subsequent reduction in temperature of screened juice.
In order to prevent escaping of vapours the Rotary Screen is provided with totally closed bolted top cover and totally enclosed feed and discharge end drums. In addition to totally closed construction of Rotary Screen it is essentially required to provide lagging followed by aluminium cladding to all stationary parts of Rotary Screen to avoid heat loss.
Hot – raw or suphited or defecated (limed) juice screening process using Rotary drum screen:
A) Hot raw sugarcane screening: Sugarcane hot juice resulting from raw juice heaters i.e. either shell and tube type, plate type heat exchangers and Direct contact type heaters containing suspended fiber particles fed to hot raw juice screening system. Screened sugarcane raw juice from rotary screen is collected in slopped bottom trough for onward transferring directly to juice reaction vessel (sulphitor or defecator) or in some cases shall collected in receiving tank by gravity for onward pumping of sugarcane hot juice for sulphitation or defecation (liming) process. The fiber / suspended matter separated at sugarcane hot juice rotary screen is discharged into the mud tank again by gravity or collected in slurry preparation tank to be pumped to mill station.
B) Hot sulphited or defecated sugarcane screening: Sugarcane hot sulphited or defecated juice resulting from reaction vessel i.e. either sulphitor in case of direct consumption white sugar production and defecator in case of raw sugar production, containing suspended fiber particles fed to hot juice screening system. Screened sugarcane sulphited or defecated juice from rotary screen is collected in slopped bottom trough for onward transferring to sulphited or defecated juice receiving tank by gravity for onward pumping of sulphited or defecated screened sugarcane juice for further heating process. The fiber / suspended matter separated at sugarcane hot sulphited or defecated juice rotary screen is discharged into the mud tank again by gravity or collected in slurry preparation tank to be pumped at mill station.