Waste Management: Page 5 of 14

GPS truck tracking

The use of global positioning systems (GPS) has proved helpful to optimize waste collection routes, improve driver behaviors and cut oper-ating expenses. These systems help waste managers ensure truck drivers are adhering to routes and schedules and that there’s no excessive idling or speeding, which can consume additional fuel.

A study published by the Aberdeen Group noted a 13.2% reduction in fuel costs with adoption of GPS vehicle tracking. There was also a 13.4% reduction in overtime costs.

GIS-based route planning

A geographic information system (GIS) is used to construct, record, analyze, manipulate and display geographic information. Many cities have had GIS systems in place for a number of years.

GIS technology is now starting to play a significant role in modern solid waste management operations. It can help with planning waste collection routes, as well as prudently siting recycling centers, material recovery facilities, yard waste depots and landfill locations.

Smart material recovery

After collecting refuse and recyclables, the recovery of valuable waste stream material can begin. Let’s now look at some of the smart processing solutions that extract waste stream assets.

Advanced material recovery facilities

An advanced material recovery facility is commonly referred to as a MRF (pronounced “murf”). It is typically a large building where collected waste enters on a conveyor belt and, as it moves forward, is separated into various piles for recycling markets.

A variety of mechanical systems are used to sort and separate the good stuff from the waste stream. Magnets pull out ferrous metal. Air jets

are used to suspend lighter plastics and paper so that heavier products, such as glass and non-ferrous metals, fall out of the stream. To identify and sort non-ferrous metals, infrared and even x-ray scanning are sometimes used. Plastics are typically sorted by hand, a practice that adds considerably to the expense of operating a MRF.

Material recovery plants generally fall into two categories. Clean MRFs only accept recyclables already separated at the collection point. Dirty MRFs accept comingled trash that includes recyclables, organic waste and everything else that goes into a residential garbage can. A dirty MRF can actually recover more material than a clean MRF because it processes the entire waste stream and targets a greater number of materials for recovery.