Sack Opening and Silo Loading
Silo loading systems connected to sack opening stations are used for discharging raw materials from sacks and fill them to storage silos. Silo loading can be done by mechanical conveyors or pneumatic conveying systems.
Mechanical Conveying Systems For Silo Loading
Mechanical conveyors can be used for silo loading from sack opening stations. Screw feeders, bucket elevators, rotary valves or chain conveyors are connected to sack dump stations to fill silos. Conveying equipment selection directly depends on conveying distance, height, transferred material and capacity. Bucket elevators are preferred for high silos. Screw feeders are preferred for shorter silos and short distances. Sack opening system can be installed on top of silo for faster filling. In this case rotary valve or butterfly valve are better choices which provide simple flow control. Dust collection systems may be needed depending on dust content of bulk solid. During silo loading, air content in the silo escapes to the atmosphere and carries some amount of dust together. Having vacuum fan and jet filter, dust collectors prevent any dust emission to the environment. Collected dust is sent back to the silo and product loss is prevented.
Silo Loading With Pneumatic Conveying System
Pneumatic conveying systems installed after sack opening units transfer the bulk material through conveying pipelines to fill silos. This configuration is useful in applications where high transfer rates and long conveying distances are needed. In production lines where raw materials are stored in warehouses far from storage silos, sack opening stations can be installed closed to warehouses and pneumatic conveying systems are used to fill silos from long distances. This design prevents extreme use of forklifts and cranes for bulk material transfer in production site and increases overall efficiency.
Pneumatic transfer systems used for silo loading utilize blower pumps or compressors. Motor power, pipeline diameter, equipment selection depends on type of bulk material, transfer distance, silo height and transfer capacity. Level sensors, jet filters and other equipment are installed on storage silos to properly run silo filling system.
Sack Opening and Mixer Filling
Mixer automation systems are used to mix dry bulk solids with respect to certain recipes. Raw materials that are delivered within sacks can be transferred to mixing units by combination of conveying equipment and sack opening system. Depending on type of application, pneumatic conveying or mechanical feeding systems can be used to fill mixers. Sack opening stations can be manufactured with built in dosing system. Amount of raw material to be loaded into the mixer is controlled automatically by the help of weighing and dosing system. Dust collectors can be used to prevent dust emission during mixer filling.
Sack Unloading and Packaging System Feeding
Dry bulk packaging systems are used to fill powdered or granular materials into bags, drums, jars, sacks etc. Bulk materials that are delivered within sacks are to be transferred to packaging machines without interruption. Loading hopper of packaging system should be kept full during filling and packaging. Sack opener systems can monitor the product level in loading hopper and maintain constant level automatically. Depending on packaging speed, mechanical conveying systems or pneumatic loading systems can be selected. Dust collectors can be used to prevent dust emission during hopper loading for materials with high dust content.
Sack Opening, Dosing, Weighing and Batching Systems
Sack opening systems can deliver dry bulk solids in powder and granular form to weighing and batching systems. Loading hopper of weighing system should be kept full during dosing and batching. Sack opening systems can monitor the product level in loading hopper and maintain constant level automatically. Depending on dosing speed and conveying distance, mechanical conveying systems or pneumatic loading systems may be used. Dust collectors can be used to prevent dust emission during hopper loading for materials with high dust content.
Sack Discharge and Bulk Truck Loading Systems
Bulk tanker trucks or open trucks are sometimes filled with powdered materials delivered within sacks. These systems are generally composed of sack opening station, mechanical or pneumatic conveyor and loading bellow. Sack opening station transfers the bulk solid from sack to conveying system. Conveying system transfers it to truck loading area. And loading bellow is used to fill tanker truck without any dust emission. Since truck loading operations are done within limited time, high capacity sack opening systems and bulk material conveying systems are used. For short distances, screw conveyors are preferred to transfer material from bag opening station to truck loading chute. For long conveying distances, pneumatic conveying systems provide better service. There may exist a storage hopper or silo above bulk truck loading bellow to compensate material flow between inlet and outlet. Sack discharge and truck filling systems have automatic control system that monitors product level in truck and operates all equipment accordingly. Optional weighing system can be added to measure the amount of material that is filled to truck.
