Avoiding a sticky situation
To clean-and speed-things up, Elk Grove Village, IL-based marshmallow producer Doumak, Inc., decided to eliminate the use of bucket elevator conveying systems.
"With their many moving parts, bucket elevators can be costly and time-consuming to maintain," says Mike Morgan, maintenance supervisor at Doumak. He estimates that the dusty environment reduced equipment lifespan by as much as 50 percent.
Cleaning such equipment required production downtime, as well. "Excess starch ended up in the bucket elevators, in bagged product and on the floor," says Morgan. In addition, marshmallows were regularly caught in the bucket elevator's pinch points, which made the equipment sticky and compromised product quality.
To solve the problem, Doumak installed two pneumatic conveyor systems from VAC-U-MAX to deliver finished marshmallows from processing to packaging. Now instead of bucket elevators dumping marshmallows into packaging machines at an inflexible pace, vacuum receivers pneumatically convey the marshmallows through six FDA, USDA-approved hoses to the packaging machines on demand.
"With pneumatic conveying, there's virtually no maintenance or cleaning necessary because they have fewer moving parts," says Morgan. "We just clean or swap out hoses and check the motor and oil twice a year. That adds about 30 hours a year to production, compared to monthly preventive maintenance on 20 or so moving parts for bucket-elevator systems."
With the VAC-U-MAX systems, vibratory pans shake excess starch from the marshmallows as they exit the cooling drums. The starch goes through filter separators and is recycled back to manufacturing for reuse. "The systems reclaim about 1,000 pounds of starch a day and reduce product loss by up to 2 percent," says Morgan. "They put the starch back to good use, unlike our old bucket elevators."
Eliminating the pinch points associated with Doumak's bucket elevators reduced excess starch in bagged marshmallows, which improved product quality. "Less physical contact means there are fewer places for sensitive product to get pinched or damaged," says Morgan.
An additional benefit of these pneumatic conveying systems is that they require 70 percent less factory floor space than the bucket elevator systems that were previously in place. The extra floor space allows Doumak to store raw materials next to the production line, saving travel time to restock at a central supply location.
"With pneumatic conveying systems, product quality is better and production is up to 15 percent more efficient than with traditional equipment like bucket elevators," says Morgan. "That's important for those of us in the food or confection industries, where 24/7 plant operation is common and downtime must be kept to an absolute minimum."
Doan Pendelton, VAC-U-MAX,