Three becomes two
September 01, 2007
by Arvin Donley
Any milling facility that has produced flour on a commercial basis for more than 140 years has undergone numerous renovations and upgrades to make its production process more efficient.
Established in 1866, the flour mill in Vaksdal, Norway, owned by Norwegian-based Norgesmollene AS, has undergone many significant changes during its long history. In 1938, for instance, new milling equipment was installed that made Vaksdal the largest flour mill in northern Europe at that time.
The mill’s most recent upgrade involved a unique challenge: replacing three older milling lines with two new state-of-theart ones while keeping production downtime to a minimum.
Two years ago, Norgesmollene decided the time had come to modernize its facility, which is located on a picturesque fjord in southwestern Norway.
"The three former mills had become obsolete," explained Olav Bruvik, production manager of Norgesmollene. "It had simply become high time to replace them by modern installations. In addition, we also wanted to further improve the hygienic situation in Vaksdal and to increase the level of automation."
TWO-PHASE PROJECT To achieve this modernization, Norgesmollene turned to Uzwil, Switzerland-based Buhler AG, which has supplied equipment to the Vaksdal mill for nearly 70 years, dating back to the major expansion in 1938.
Buhler’s task was to install a wheat mill with a flour production capacity of 320 tonnes per day and a combined mill (wheat, rye, barley) with a daily capacity of 150 tonnes.
Plant Manager Rune Johnsen said the biggest challenge was minimizing production downtime, which ended up being just a little more than two weeks.
The revamping of the mill took place in two phases. While the new wheat mill line was being installed in August 2005, Norgesmollene was able to keep its two existing lines in operation, he said. The combined mill was completed about a year later.
"Everything went as planned, and the result was very satisfactory," Johnsen said.
He said the newly renovated mill takes in a mixture of different wheat varieties with help from flowbalancers on the intake cells. Once in the cleaning house, the wheat goes through a Combicleaner, indent cylinders and dampening. It then goes through a scourer for second cleaning before entering the automated mill, which is operated using Buhler’s Win-CoS control system.
After the flour is milled, it is pneumatically conveyed 230 meters to the top of the flour silo, where it is eventually sent to packaging or bulk loading, or for further mixing.
Johnsen described the design of the mill as "very compact and space saving."
Norgesmollene was most pleased about the improvements that were made in regard to sanitation in the new mill, which features stainless steel gravity spouts throughout.
"We don’t have any flour collecting auger; instead we collect the flour in small collecting bins for hygienic reasons," Johnsen said.
Most of the wheat milled at Vaksdal — about 50% to 70% — is sourced locally, he said, with the rest coming from imports. Grain storage capacity at the plant is about 50,000 tonnes, and is shared with a local feed producer.
The Vaksdal mill, which Johnsen says has a utilization rate of about 90%, produces a wide range of products, primarily for the Norwegian market.
"We produce wheat, rye and barley flour in different granulations — both whole grain and sifted," Johnsen said. "We also produce durum semolina, flour mixes and pasta in Vaksdal."
Johnsen noted that like many other countries, Norway’s milling industry went through a period of consolidation during the 1990s and into the first part of this decade, although that trend appears to have subsided a bit. "The capacity is now very stable," Johnsen said. Total flour consumption in Norway in 2006 was about 300,000 tonnes.