Processing Magazine

Vacuum conveyors provide hygienic sugar handling solution for cereal manufacturer

April 24, 2006

Introduction: Consumer Demand for the Most Important Meal of the Day

Many people regard breakfast as the most important meal of the day and most health experts will suggest that it is far better to eat a balanced breakfast, rather than skip breakfast altogether and end up snacking all day. Although a traditional American breakfast might once have included sausage, eggs, home fries and pancakes, we now opt for quicker and healthier options, like ready-to-eat (RTE) cereals and nutritional bars. Besides taking less time to eat, these newer breakfast options promise to be high in nutrients and low in fat—and they have proven to be very lucrative for the food processing industry. In fact, the US cereal market was recently estimated at a whopping $8.9 billion.

Background: Cereal Manufacturing at Weetabix

A key player in the RTE industry is Weetabix Ltd., a $630 million multinational company headquartered in the United Kingdom. Manufacturing RTE cereal since the 1930s, Weetabix now manufactures in multiple countries around the world, and its brands are sold wherever RTE cereal is an established part of daily eating habits.

Part of the company’s success can be attributed to its extensive investment in the development of innovative cereal products. Since its inception, the company has leveraged a team of trained food scientists, microbiologists, and food engineers to ensure the creation of not only delicious, but also safe and nutritious cereals.

While Weetabix manufactures its own popular brands such as Weetabix and Alpen, a significant portion of the company’s business is private labeled. For example, Weetabix Canada, a subsidiary of Weetabix Ltd, processes recipes for nearly one hundred brands of cereals for the Canadian, American and British markets.

The Challenge: Automated Handling of Granulated Sugar for Private Label Customer

One of Weetabix Canada’s recent innovations came in the way of a private label customer, whose recipe included a proprietary mix of sugar-coated flakes. In order to best fulfill its customer’s needs, Weetabix decided to automate material handling processes at its manufacturing plant in Cobourg, Ontario.

Specifically, Weetabix wanted to replace its existing manual method, which was a laborious process that required workers to lift extremely heavy sacks, filled with granulated sugar, and pour them into the blender where the sugar was then mixed with water.

“With the existing method, our employees had to manually lift and carry the bags,” said Al Cane, Engineering Project Coordinator. Cane is a 25-year Weetabix veteran in charge of plant operations. “This was a time-consuming and labor-intensive process and also created a situation where workers could hurt their backs lugging around these heavy loads.”

In order to automate the existing process, Cane partnered with Ron Hull, an executive at Weetabix’s automation distributor, George T. White, a leading provider of automated industrial solutions.

The Solution: PIAB Custom Vacuum Conveying System with Transition Pieces

To most efficiently automate Weetabix’s sugar handling application, Hull recommended that Cane install a sanitary, stainless steel pneumatic conveyor from PIAB Vacuum Products, based in Hingham, MA.

As PIAB’s exclusive representative in Ontario, the George T. White Company regularly works with manufacturers to install PIAB’s conveyors in challenging bulk material handling applications.

“PIAB’s custom conveying solutions help our customers raise productivity on a regular basis,” said Hull. “They are ideal for applications that demand the highest possible degree of safety as to hygiene and operation.”

Among the most pressing issues was how to ensure that the granulated sugar was moved efficiently without getting stuck in the conveying system from exposure to steam from the hot water, which later mixes with the sugar and “frosts” the cereal flakes.

Because of the complex nature of the application, Weetabix required custom connecting points and controls to smoothly and safely transfer the product to the coating line.

“This application was challenging because it required a unique transition piece to allow steam to vent prior to going up the discharge piping. The goal was to prevent the sugar from crystallizing and sticking to the dump valve of the conveyor,” said Hull. “I was confident in PIAB’s ability to provide the necessary transition pieces that Weetabix required,” said Hull.

The Process: Safely and Effectively Conveying the Sugar

Cereal coating is a cumbersome process which requires several stages, one of the first of which begins when the granulated sugar is delivered to the plant in large super sacks. The sacks are then placed on fork lifts where they are picked up by a hoist that hangs the sacks over the feed station, where the sugar is dumped from an opening at the bottom of the sacks. At the bottom of the feed station is a feed adapter which connects to the vacuum conveyor where vacuum is generated by a compressed air-driven PIAB vacuum pump.

Vacuum draws the sugar through a vacuum line about 30 feet into a vacuum receiver, which is a batch cycling system. From the receiver, the sugar is discharged into a blender filled with hot water. The sugar mixes with the hot water and the mixture is moved to next stage of the processing line to coat the flakes.

In order to prevent the steam from coming up from the blender and causing the sugar to crystallize and stick on the bottom valve, Ron Hull worked with Al Cane to come up with a customized solution that included a transition piece from PIAB. Hull designed the piece so that it fit properly between the vacuum receiver and the blender. The transition piece allows the sugar to flow freely from the conveyor, but keeps the steam from entering and causing the sugar to coat and stick to the dump valve.

“An extra module was also installed to raise the filter above the inlet to prevent the sugar from contacting the filter and thus causing abrasive damage. It also preserves the life of the filter and thus reduces downtime because regular filter replacements are needed less often,” said Hull.

Results: Safe, Ergonomic and Cost Effective Handling

By installing the automated conveying system, Weetabix has now eliminated any unnecessary bending, lifting, and other movements that could be detrimental to its employees.

“We were able to reassign one of our full-time workers to a more productive task, realizing a cost savings of 8 hours per day,” said Cane.

Cane has also welcomed the lack of maintenance issues. “We schedule a preventive maintenance check once every three months, and that heads off any possible problems and keeps the conveyors running smoothly. Our employees appreciate the fact that it is simple to operate and requires almost no repairing.”

Reliability and sanitary design have proved to be particularly beneficial for easy compliance with food industry regulations. “The conveyors are very dependable, well-designed and extremely clean. Our inspectors like the fact that the system eliminates almost all risk of contamination.”

The success of the conveying system has prompted Weetabix to purchase additional systems for other bulk material handling applications. “We recently purchased a couple of smaller PIAB conveyors for feeding extruders and we plan to purchase another system in a few months.”

Stop by Booth 1359 at the Powder Show to view these vacuum conveyors live.