Storage and Conveying for Dissolving Sugar in a Cast Iron Tank
Company
Sugar processor specializing in the manufacture of spirits and syrups.
Materials handled
Crystal beet sugar delivered by tanker truck, and cane sugar packaged in 1,000 and 1,200 kg bulk bags.
Solution
The installation concerns crystal sugar storage and conveying line to a sugar dissolution tank for syrup manufacturing. The customer wanted the process to have two separate processes, one for beet sugar and the other for the cane sugar. The controls and operation of this installation differed depending on the type of sugar handled: (1) automatic for beet sugar; (2) semi-automatic for cane sugar.
The line must meet the following requirements:
. No cross-contamination of products
. Minimize any potential product loss
. Product change over times reduced to a minimum
Sugar beet storage and transfer unit
Crystal sugar, of beet origin, is conveyed by tanker into a storage silo with a capacity of 4,060 ft³. The storage silo is fitted with a level probe and a vibrating bottom plate to facilitate product flow. A manually operated knife gate valve isolates the flow of the sugar material.
The material is transferred by means of a mechanical tubular screw with a diameter of 8.5 inches. The screw conveyor is positioned at the silo intake which ensures a mass flow of 11,020 lbs/hr.
A gearbox is positioned at the outlet of the dosing screw to convey the material to the pneumatic transfer with remote filter.
A line purge system is installed to prevent cross-contamination in the duct work with an automatic valve closing to stop the powder flow so the entire pipework can be evacuated. The valve is then instantly reopened to remove the remaining air/product mixture from the ducts.
Cane sugar emptying and conveying unit
Cane sugar is delivered in bulk bags of 2,200 and 2,645 lbs. To avoid the operation of unpacking the flexible containers, PALAMATIC PROCESS installed a bulk bag emptying station fitted with a self-supporting frame for the bulk bag installation. An electric hoist on a rail allows easy handling and loading by the operators and flow of the material is aided by a vibratory table. This emptying station, designed for manual opening of all types of bulk bags, limits dust emissions to a minimum for a healthy and safe working atmosphere. Finally, a screw conveyor takes the cane sugar to the dissolving tank.
The pneumatic transfer system with remote filter - VFlow:
The processed materials, beet and cane sugar, are conveyed into a continuous discharge cyclone via a rotary airlock valve for discharge into the dissolution tank. The remote cyclo-filter recovers the fines and reintroduces them into the process. This pneumatic transfer system offers many advantages:
. Conveying of material with challenging flow properties
. High throughput rates
. The separation and recovery of fines
. Recycling of fines in the process
. Protection of the filter against possible steam ingression during reactor loading.