One of the highest ideals of sustainable materials management is that products, components and materials are kept at their highest utility and continually circulate in a restorative system. Often referred to as circularity, in optimized systems there is very little “waste” because outputs from one process are utilized as inputs in another process. Energy is a required input into this system and powers the reintroduction of end-of-life materials into new products. Also needed is the safe and effective management of residuals that may not be suitable for circularity.

All of Covanta’s WTE facilities have important roles to play in the circular economy by safely managing residues, recovering energy, recycling metals and materials, exporting electricity to the grid and, at combined heat and power plants, providing steam to customers. At certain WTE facilities, however, we can more directly integrate the circular economy into a form of industrial symbiosis, whereby energy and materials are used as inputs in local and colocated facilities and processes. The colocation of a WTE facility alongside manufacturing assets and other infrastructure can create efficient linkages and provide direct reuse of materials and recovery of energy.

A prime example of the industrial symbiosis model is the collaboration between Covanta’s WTE facility in Niagara Falls, New York, and Greenpac Mill, a recycled paper manufacturer. Steam generated by Covanta during the combustion of Greenpac’s nonrecyclable waste is returned and used to dry the paper Greenpac produces. Covanta converts the byproducts of the mill’s recycling process into electricity and captures thousands of tons of metal for recycling. In turn, the mill provides a local outlet for recycled paper.

“Our employees believe in our partnership with Covanta. They enjoy coming to work and, most of all, they speak confidently about the company when they are outside of our buildings, which drives positivity in the community. We set out from day one to have a green presence, and we continue to look for ways to improve and be more creative.”

Murray Hewitt, Greenpac General Manager

Europe and the Circular Economy

The European Union is working to advance the circular economy, in part by reassessing the success of its historical waste management policies. Some countries have achieved and surpassed their goals. Germany, the Netherlands, and Sweden, among other countries, have enacted legislation and other public policy measures to promote circular economy principles and to minimize the use of landfills as a waste management option. These countries are assessing the appropriate amount of WTE capacity to ensure continued compatibility with recycling. Other EU countries still landfill a significant portion of their waste and recycle comparatively little. The question is not whether WTE will have a role in waste management, but rather how to achieve the optimal balance of sustainable waste management with the lowest environmental impact.