Cleaning Up

by Emily Wilson
Share This:

Cascadia Terminal at the Port of Vancouver utilizes its high-tech cleaning systems to keep the terminal profitable

The Pre-Conference Tour of the GEAPS Exchange 2002 offered a close-up look at some of the technology used at Vancouver Wharves and the Cascadia Terminal, both at the Port of Vancouver. Here, we present a small slice of the that tour — the modern and efficient cleaning system at the Cascadia facility that inspired more than a few admiring nods. (For more coverage of the GEAPS Exchange 2002, see pages 40-45.)

The largest grain elevator in the port, Cascadia has a storage capacity of 283,000 tonnes, an operating capacity of 190,000 tonnes, and it handles about 50% of the grain that goes through the port. The plant’s extensive cleaning system includes 31 primary cleaners that clean 1,100 tonnes of grain per hour.

The terminal, a joint venture between Cargill Limited and Agricore United, has been able to draw on the strengths of both companies, said Gerry Dickie, Cascadia’s terminal manager for the past eight years.

The facility boasts a new canola cleaning system and new primary cleaning systems in both workhouses. Most significantly, the facility has gone from a cylinder cleaner system that often required two or more passes to reach export standards to a single-pass, high-throughput system consisting of rotary cleaners, cylinder cleaners and inline reclaim.

"Canada’s cleaning systems were developed to position us as a niche marketer over the last 70 years," Dickie said. "In the last 10 years this has helped us as our customers have become more quality conscious. The standards for cleanliness are legislated by statute, but we are seeing more and more cleaning to customers’ own required specifications."

THE CLEANING PROCESS

The primary cleaning systems were replaced in the last two years in Workhouse 1 and Workhouse 2. The new cleaning systems clean wheat, barley and canola and are highly automated.

The first cleaning step at Cascadia is aspirating the grain to remove chaff and to scalp it for large material. To operate the new systems in Workhouse 1, the terminal uses closed circuit aspirators that are more energy efficient and environmentally friendly than previous technology. Then grain moves to one of the two cleaning systems that were installed. One version uses rotary cleaners first to remove the screenings from the parent grain.

"This is a sizing function, and by varying the size and shape of the screen opening you can vary the separation," Dickie said. "The screenings go directly to a large reclaim system to recover any whole grain lost and to separate out marketable by-products."

The "overs," or large grain, go to a set of cylinder machines that remove the wild oats and unthreshed wheat (wheat heads) from the parent grain. The "tailings," consisting of unthreshed wheat, wild oats and large kernels of grain, go to the inline reclaim that recovers the wheat and puts it back with the parent grain. Unthreshed wheat and wild oats go to a reclaim system for further recovery.

In the second cleaning system, grain travels after initial aspirating to a cylinder system, rather than the rotary cleaners. There, parent grain is split into two streams: large material with wheat heads and wild oats goes in one direction and the smaller wheat with screening then goes directly to a single rotary cleaner. The wild oats and wheat heads get separated out on another row of cylinders.

Some of the most advanced pieces of cleaning equipment at Cascadia are the rotary cleaners with multiple separation capabilities for cleaning multiple types of grain. "These are the backbone of our cleaning systems," Dickie said. "The closed circuit aspirator and inline reclaim machines are two recent innovations. The cylinder machines have been revamped with ceramic liners, polychain drive systems and better engineered shafts and bearing systems.

These improvements have dropped maintenance costs at the terminal from about $100,000 per cleaning section to only a few thousand dollars.

IMPROVED BOTTOM LINE

Cascadia’s cleaning system is not only efficient, it is also profitable.

"Our cleaning systems are so elaborate because in Canada we do not have shrink at the terminal position," Dickie said. This means the terminal cannot afford to lose grain, which is very difficult when grain must be cleaned to standard on the first cleaning pass. To reduce that loss, the facility invested C$6 million in high-tech systems that reclaim large wheat lost in the cylinder cleaning process and put it back with the parent grain. "This is very important because it allows the reclaimed grain to go back into the parent grain at the correct grade," Dickie said. "This reduces the blending required to recover losses."

The terminal also gains ownership of the foreign material in each rail car of grain. For instance, if a 100-tonne car comes in with 2% dockage, the terminal is responsible to deliver 98 tonnes of grain and owns the remaining two tonnes of dockage, which needs cleaning to get the best possible return.

"The facility removes the dockage through the cleaning process," Dickie said. "The dockage then goes to reclain systems — nothing is wasted."

There are two main reclaim systems. The screenings reclaim system recovers small wheat. It produces a by-product consisting of cracked wheat and weed seeds and a refuse dust that goes for pelleting. The second system is the tailings system, and it recovers large wheat and the wheat from the unthreshed heads. It makes a wild oat by-product. Chaff from this system goes for pelleting.

In addition, all of the facility’s dust systems and the refuse from the reclaim systems go to its pellet mill, where it is turned into a ground screenings pellet.

"What makes this system great is the one-pass cleaning and the flexibility to clean almost any type of grain with minimal changes required to the configuration," he explained. "The cleaning systems are in the middle of our process. They affect our receiving rate and can affect shipping if the grain is not ready. Cleaning capacity is balanced with receiving capacity. Anyone can clean grain," Dickie said, "its doing it without losing your shirt that is hard."

Partners