MSW for Energy Recovery – 2020-2035 Scenarios for a Large City

The generation rate, total amount and composition of Municipal Solid Waste (MSW) can be affected by many parameters such as population and economy growth, unfolding of Circular Economy, implementation of new regulations for material recycling and development of sorting and recycling technology. Such changes will also affect measures to treat/utilize the MSW as well as the handling of the residues, primarily ashes.

In this work, three scenarios on the future MSW sent to energy recovery for the period 2020-2035 have been developed using detailed MSW composition data from a large Scandinavian city, namely Oslo, Norway. The amount and composition of the MSW sent to energy recovery (incineration) were estimated according to different boundary conditions including population growth, improvement of sorting efficiency and increase of recycling rate. This work also evaluated key properties of the MSW sent to energy recovery under different scenarios, including heating value, volatile matter and carbon content and concentration of key ash-forming elements relevant to the operation of an incinerator and ash valorisation.

Three scenarios were developed and assessed in terms of the amount and composition of MSW:

Current Road scenario. This scenario is considered as ”Business as usual”. Yearly historical changes of each waste fraction per capita were calculated from available statistical data for the years 2015 to 2019 and their averages were used as the input to the scenario implementation.

Circular Road scenario. This scenario focuses on assessing the effects of improved sorting on the different waste fractions. For this scenario, the total amount of MSW and waste fractions generated each year are kept the same as in the current road scenario. However, assuming an improvement in sorting behavior, an increased fraction of each recyclable waste fraction found in the residual waste container, due to wrong or improper sorting, are now “moved” to proper separate collection.

Frugal Road scenario. The Frugal Road scenario focuses on the impact of waste reduction on the amount and composition of waste to be recycled and incinerated.

Results from the current work indicated that: (1) the evolution of both population (the number of inhabitants), consumption (i.e., waste generation rate per inhabitant) and sorting behaviours have large impacts on the amount and composition of the MSW for energy recovery, (2) increased sorting of MSW at the household level can have significant consequences on the amount and composition of MSW generated for energy recovery. It is very clear for the largest recyclable fractions found in MSW such as paper, plastic and food waste, (3) key combustion properties of MSW to WtE are generally towards lower ash and energy content under the three scenarios, how this might impact plant operation should be studied further, (4) ash concentration (as well as the concentrations of certain inorganic elements) gradually decreases from the year 2020 to 2035 under three scenarios, but to different extents.

Figure 1. MSW for the WtE for year 2020-2035 under the three scenarios

Figure 2. Composition of MSW to WtE in 2019 (a) and in 2025 under different scenarios (b,c and d)

Read more: The full article: https://www.cetjournal.it/index.php/cet/article/view/CET23105092

This work is part of the Waste-to-Energy and Municipal Solid Waste management systems in Circular Economy (CircWtE) project led by SINTEF Energy Research and co-funded by industry and public partners and the Research Council of Norway (CircWtE – 319795). For contact see https://www.sintef.no/en/projects/2021/circwte-waste-to-energy-and-municipal-solid-waste-management-systems-in-circular-economy/