Circular Screen Separator Helps Chemical Manufacturing Boost Utilization and Quality
When AMVAC Chemical Corporation, Los Angeles, CA, began producing dry powdered agricultural product, plant personnel found that lumps from about 1 in. (25.4 mm) to 2-1/2 in. (63.5 mm) inch diameter hampered the bag filling operation. To address these quality and productivity concerns, AMVAC installed a circular screen separator to eliminate these lumps and to ensure that the product is powdery before it is packaged.
Batches are released from the dryer three or four times per day, explained AMVAC Chemical Corporation Director of Engineering Henry Berti. The product is de-agglomerated on the screen and the remaining lumps are separated for recycling. To maximize throughput of the product on the 20 mesh screen, the 30 in. (760 mm) diameter Kason VIBROSCREEN Circular Screen Separator is equipped with brushes that rotate as the machine vibrates. This de-agglomerates most lumps, reducing the amount of material required to be recycled, and thereby increases the bag filling operations efficiency. The lumps, which may make up as much as 5 percent of the product, are separated from on-size powder particles at a rate of approximately 4000 pounds (1800 kg) per hour and brushes de-agglomerate the lumps.
Since the product is prone to agglomerate due to static electric charge, Kason engineers and local representative Steve Garfield of Rexmark Engineering Company offered suggestions for minimizing its impact on separation efficiency. After studying AMVAC Chemical's product in the Kason Test Laboratory and on-site inspection in Los Angeles by Garfield, a conductive gasket was installed to ground the equipment to the structure beneath the VIBROSCREEN unit, thereby minimizing static buildup.
Unlike most companies that mount circular screen separators on a manufacturing plant floor, AMVAC Chemical has mounted its unit approximately 40 feet (12.2 m) above the floor to permit gravity feeding into a hopper. This circular screen separator is securely mounted over a large hopper that feeds into the bagging operation.
The VIBROSCREEN unit has served well since March 1991 when it was first installed. Because it can screen at rates up to about 8500 pounds (3860 kg) per hour, The VIBROSCREEN unit can satisfy capacity increase demands for some time to come.
AMVAC Chemical installed the VIBROSCREEN under a trial purchase arrangement and eventually purchased this separator. Kason's ability to provide reliable machines that can be modified for specific processing lines and applications, and the trial purchase arrangement met AMVAC's needs particularly well.
Screen Tips - Volume 8, Number 3 1993