Annestad is a new little suburb a bit south of Malmö in Sweden, a stone’s throw from the Öresund Bridge abutment. Given its proximity to the neighboring country of Denmark, it is also known as Dane Town. Envac has installed a small vacuum system in Annestad which serves some 840 apartments. The system was taken into operation in 2006.
Small system
Annestad consists both of housing cooperative flats and tenant owners apartments. Hyreshem Malmö owns the Envac vaccum waste installation and in turn has put the area’s property/facility management in the hands of Kanslihuset Fastighetskonsult AB. The system is relatively small, a F-system with a pipe diameter of 350 mm and a 55 kW fan with 20 inlets located in the yards with a maximum suction distance of 420 m.
Since its start-up, Envac Service in Malmö is responsible for the operation and maintenance of the installation, a contract signed with Hyreshem Malmö. According to Rolf Hansson, property manager with Hyreshem Malmö, "We inform all new tenants that we have a waste vacuum system in the area. Cooperation with Envac has been very close and there has never been cause for complaints".
Major savings
The Annestad system has three distinct pipe branches with section valves located close to the collection station. As the system is immediately above sea level, the inlets, which are all located outdoors, have small intermediate storage chutes and the pipes are installed close to the ground. During the summer and autumn of 2009, Envac upgraded the system by installing frequency converters and a new EAP operating system, which allowed us to activate VDOT (Valve Dynamic Open Time).
Together, these measures resulted in a reduction of 58 percent in operating energy consumption per month, and chute stoppages were reduced by 70 percent thanks to the improved regulation of air speed. Today the installations consume approx 80 kWh/ton and on average process some 20 tonnes waste per month. “The system simply functions quite outstandingly well. I am able to say this based on my experience as a property manager, and compared with other waste disposal systems, such as shredders for example” says Rolf Hansson, property manager for Hyreshem Malmö.
Still growing
Since the very start, Annestad has had level sensors installed and therefore emptying times have been programmed partly at determined times and partly via levels. Today, Annestad processes one waste fraction alone. The system could be expanded to more fractions through the installation of more inlets and through an expansion of the station.
In the meanwhile, Annestad is still growing and in the plans more buildings will have the vacuum waste system installed. “We are pleased to have a stationary vacuum waste system in the area and are happy that the new buildings, which are planned, will be connected to the existing system. However, the recycling areas with traditional waste handling in the yards which act as collection points for recycling leave something to be desired. We could do with an inlet there,“ says Rolf Hansson.
In the future, a cooperative society between the individual tenant owners associations and Hyreshem Malmö is being contemplated, which will then take over ownership of the installations. However, today it is Envac who monitors the operations and maintenance costs and invoice the corresponding user.