This is the reclaiming of ‘thrash’ materials that have for so long been considered ¬as waste and destined to the landfill. It involved collecting, sorting (and sometimes grading) and processing of waste into compost or new raw materials that are used in manufacturing new products. The most used waste recovery programs involve energy recovery, recycling and composting.
Energy recovery involves the conversion of non-recyclable waste into heat, by gasification, combustion or otherwise, and further converted into usable energy. This process is also called Waste-To-Energy (WTE). In 2011, about 29million tonnes of MSW (12%) was combusted for energy use, generating over 2700Megawatts of power per year.
Recycling involves the conversion of waste or used materials such as glass, metals, paper, aluminium, plastics and others into their raw material state to use again. It has become a very important function of many waste management and environmental organizations recently because it has helped reduce our dependence on fresh raw materials, created a lot of jobs and saved a huge chunk of waste that would have ended up in landfills.
Composting recovery process involves the conversion of organic waste (food waste), with the help of bacteria, moisture and aeration. Composting ends up compost, a high-nutrient soil type that is used to fortify farm soils. Heat can be extracted from large composting units, which is an added bonus to the facility.
Over the past decade, education, information and public engagement, especially in developed countries, has yielded some interesting results. In 1996, 27% of Municipal Solid Waste (MSW) was recovered in the USA, exceeding the national goal of 25% set by the U.S. Environmental Protection Agency (EPA). “In 2012, Americans generated about 251 million tons of trash and recycled and composted almost 87 million tons of this material, equivalent to a 34.5 per cent recycling rate. On average, Americans recycled and composted 1.51 pounds out of our individual waste generation rate of 4.38 pounds per person per day”1
In spite of this achievement, there is still a lot of usable waste that is not recovered here in the USA and abroad. In Europe, Norway leads the way in the Waste-To-Energy business, with many countries in the region exporting their waste to feed its plants. Germany and Sweden follow with the importation of waste. “At the moment, the city of Oslo can take 410,000 tonnes of waste a year and we import 45,000 tonnes from the UK. Europe as a whole currently dumps 150m tonnes of waste in landfills every year, so there is clearly great potential in using waste for energy.”2
The residue from WTE is ash, which is sent to landfill. Waste recovery is not entirely a cheap technology, and there are also concerns that environmentalists raise with this technology. However, many people believe that it is the lesser of the two evils.
*1. Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2012. www.epa.gov/waste/nonhaz/municipal/pubs/2012_msw_fs.pdf *2. Helen Russell, Trash to cash: Norway leads the way in turning waste into energy. The Guardian, Friday 14 June 2013