Kafferosteriet Löfbergs was founded in 1906 and is now one of the biggest coffee roasters in the Nordic region producing 29,000 tonnes of coffee in 2013. The head office is situated in Karlstad (Sweden), where Kafferosteriet Löfbergs also has one of its main roasting plants. Other roasting plants are located in Viborg (Denmark), Sandefjord (Norway) and Riga (Latvia).
In 2000 and 2002 respectively, Löfbergs changed to two new centrifugal roasters (unitary capacity: 4 tonnes of green coffee per hour) with recirculation, preheating technology and an exhaust gas cleaning system with a low-temperature catalyser (working temperature 450°C). One roaster is equipped with automatic gap adjustment and the second is planned to be retrofitted with the same system shortly (Kafferosteriet Löfbergs 2013).
A central aspect of the redesign was to decrease the carbon footprint, by saving fuel (LPG) through thermal preheating of the coffee, and increase efficiency at the same time.
The level of propane consumption before and after changes of the machines (new roasters with green coffee preheater and low temperature catalyser, was reduced. Depending on the type of coffee produced when the rosters were changed, energy savings of approximately 20% and a 20% increase in throughput were achieved.
All air outlets at this facility go to a central dust absorption unit with tubefilters. From the star valve outlets on the cyclones and the destoner units, all chaff is sent to a pellet press to be pelletised. The dust emissions associated to the preheater system (excluding emissions with roasting exhaust gases), do not exceed 10 mg/m3.