ENVAC:AN INNOVATIVE Swedish waste collection system called Envac that uses vacuum pumps to suck waste from bins into a central biogas burner is to be installed at Cité Verte, a green city development in Quebec in Canada.
A system of underground pipes will connect directly to waste drop-off points for organic waste, recyclables and all other types of refuse. A powerful vacuum is created to suck the material into a local substation, where the organic waste is turned into biogas, the recyclables are processed and the other waste is incinerated to produce electricity or heat.
It takes 10 seconds to empty a bin and waste may travel as much as eight or nine kilometres at up to 50km/hour, according to Envac. The system is entirely automated, the substations are unmanned and the same piping is used for all types of waste, with cleaning taking place at intervals along each pipe.
A total of 100,000 people in Stockholm are already served by an Envac system. Other existing installations are in China, South Korea, Barcelona and Palma de Mallorca.
While the system is expensive to install, the running costs are very low compared to conventional waste-collection systems, the company says. The main advantage of the system is that the need for regular waste collections by truck is avoided, saving money, manpower and carbon emissions.