In its crudest form, mixed municipal waste has little value. The individual materials contained in mixed municipal waste, however, do have value: once recovered, they can replace virgin materials in the manufacture of new products, and removing them from the waste stream reduces the amount of waste sent to final treatment. Waste sorting plants can be used to recover materials from the municipal waste stream by acting as a filter between collection and disposal.
Interacting economic and policy drivers provide a framework for implementing and operating waste sorting plants. The economic drivers for material recovery are the value of the material recovered, the costs associated with alternative waste management routes, and any additional direct funding of subsidy provided. Policy tools play a vital role in moderating this framework: landfill and incineration taxes, landfill bans and recycling targets on the one hand create supply push, and Green Public Procurement (GPP), raw material taxes and industry targets on the other create demand pull. Both the push and the pull effects help drive material recovery from waste and waste sorting plants as a technical solution.
