- Waste-to-energy (WTE)
- Thermal treatment
- Energy recovery
- Chemical recycling
- Circular Economy
Incineration is the process of burning waste. Most incineration facilities use the resulting heat to generate a small amount of electricity, and industry refers to them as waste-to-energy (WTE) facilities. Most commonly, incinerators burn mixed municipal solid waste that includes plastic waste, but sometimes waste is pre-treated or sorted to reduce moisture content or the amount of hard-to-burn materials like electrical appliances.
In addition to generating energy, the incineration process also produces carbon dioxide emissions, air pollutants, fly-ash, and other solid waste residue. Incineration should not be confused with other thermal treatments like those involved in chemical recycling or plastic-to-fuel processes, which use heat to convert plastic waste into liquids or gases that can either be made into new plastic or burned as fuel.
Bans & Restrictions
Waste incineration has been banned at national, state, and local levels, as in the Philippines, Guam, the state of Rhode Island, and the Finger Lakes Region of New York State. Some of these laws, however, have faced or are currently facing challenges, repeals, or exemptions for individual WTE facilities.
Waste incineration falls short of being an effective solution to the plastics crisis on a number of fronts. First, waste incineration incentivizes and relies upon the continued production of waste, including plastic waste. Incinerators, which usually burn mixed municipal solid waste, depend on energy-dense materials like plastic to maintain high burn temperatures and generate heat. Without enough plastic in the waste stream, incinerators require other fossil fuel inputs to effectively incinerate organic matter and hard-to-burn materials in the waste stream.
In China, for example, incinerator operators routinely add coal to the municipal waste to make it combustible.((M. Adams. (2012). A Greener Shade of Grey: A Special Report on Renewable Energy in China. The Economist Intelligence Unit Limited. https://www.eiu.com/public/topical_report.aspx?campaignid=ChinaGreenEnergy ))((Roberts-Davis, T.L., Guerrero, L.B. (2018). ADB and Waste Incineration: Bankrolling Pollution, Blocking Solutions. Global Alliance for Incinerator Alternatives. https://www.no-burn.org/wp-content/uploads/ADB-and-Waste-Incineration-GAIA-Nov2018.pdf)) Incinerator companies therefore, have an incentive to keep plastic in the municipal waste stream, rather than implement strategies to reduce, reuse, or recycle plastic waste. For this reason, incineration often competes with local recycling systems for plastic, and can take livelihoods away from waste workers, waste pickers, recyclers, and plastic haulers.((Luthra, A. (2017). Waste-to-Energy and Recycling. Economic & Political Weekly, 52(13), 51.))((Gerdes, P., & Gunsilius, E. (2010). The waste experts: Enabling conditions for informal sector integration in solid waste management. Deutsche Gesellschaft für Internationale Zusammenarbeit. https://www.giz.de/en/downloads/gtz2010-waste-experts-conditions-is-integration.pdf ))((Global Alliance for Incinerator Alternatives. (2013). Waste Incinerators: Bad News for Recycling and Waste Reduction. GAIA. https://www.no-burn.org/wp-content/uploads/Bad-News-for-Recycling-Final.pdf))
Beyond the conflict it creates with other plastic waste solutions, incineration generates new issues by converting plastic waste into carbon dioxide and pollutants. Conventional plastics burned in incinerators are fossil fuels, and for every tonne of plastic burned, as much as three tonnes of CO2 are released into the atmosphere.((Material Economics. (2018). The Circular Economy – a Powerful Force for Climate Mitigation. Material Economics. https://materialeconomics.com/publications/the-circular-economy-a-powerful-force-for-climate-mitigation-1))
Incineration produces more greenhouse gas emissions per unit of energy produced than any other form of energy production.((Tangri, N. V. (2021). Waste Incinerators Undermine Clean Energy Goals. Earth ArXiv. https://doi.org/10.31223/X5VK5X)) Along with greenhouse gases, incineration also generates toxic emissions that include dioxins, particulate matter, carbon monoxide, nitrogen oxides and other acidic gases (SOx, HCl), metals (cadmium, lead, mercury, arsenic, and chromium), polychlorinated biphenyls (PCBs), and brominated polyaromatic hydrocarbons (PAHS).((The New School Tishman Environment and Design Center (2019). U.S. Solid Waste Incinerators: An Industry in Decline. https://grist.org/wp-content/uploads/2020/07/1ad71-cr_gaiareportfinal_05.21.pdf ))((Azoulay, D., Villa, P., Arellano, Y., Gordon, M. F., Moon, D., Miller, K. A., & Thompson, K. (2019). Plastic & Health: The Hidden Costs of a Plastic Planet. CIEL. https://www.ciel.org/reports/plastic-health-the-hidden-costs-of-a-plastic-planet-february-2019/)) These byproducts not only risk the well-being of workers and nearby residents that are directly exposed to emissions, but also pose a larger risk when they are deposited in the open environment where they can accumulate in waterways and the food chain.((Tait, P. W., Brew, J., Che, A., Costanzo, A., Danyluk, A., Davis, M., … & Bowles, D. (2020). The health impacts of waste incineration: a systematic review. Australian and New Zealand Journal of Public Health, 44(1), 40-48. https://doi.org/10.1111/1753-6405.12939))((Allsopp, M., Costner, P., & Johnston, P. (2001). Incineration and human health. Environmental Science and Pollution Research, 8(2), 141-145.))((Petrlik, J., & Bell, L. (2020). Toxic Ash Poisons Our Food Chain. Prague, Perth: IPEN – Arnika – NTN. https://ipen.org/sites/default/files/documents/ipen-toxic-fly-ash-in-food-v2_3-en.pdf)) Moreover, in the case of dioxins, the periodic emission testing methods used in most countries do not capture episodes of high dioxin releases, which can only be found through continuous monitoring, a practice which many developing countries have no capacity to conduct.((Jurgen, R., Weber, R., & Watson, A. (2008). Validation Tests for PCDD/F Long-Term Monitoring Systems: Short Comings of Short Term Sampling and Other Lessons Learned. Organohalogen Compounds, 70, 521-526.))
While modern air pollution control equipment can help reduce the amount of toxins in an incinerator’s exhaust gas, it does so by concentrating some of the toxins in other byproducts like ash and wastewater.((Petrlik, J., & Bell, L. (2020). Toxic Ash Poisons Our Food Chain. Prague, Perth: IPEN – Arnika – NTN. https://ipen.org/sites/default/files/documents/ipen-toxic-fly-ash-in-food-v2_3-en.pdf)) The resulting toxic ash, which can represent over a third of the original burned material, is often disposed of in landfills where it can easily be spread by wind into the surrounding environment.((Petrlik, J., & Bell, L. (2020). Toxic Ash Poisons Our Food Chain. Prague, Perth: IPEN – Arnika – NTN. https://ipen.org/sites/default/files/documents/ipen-toxic-fly-ash-in-food-v2_3-en.pdf)) In other cases, incinerator ash is used as a supplement in concrete or asphalt, and is even used as fertilizer for agriculture, further increasing the risk that incineration byproducts end up in the environment and in people’s bodies.((Petrlik, J., & Bell, L. (2020). Toxic Ash Poisons Our Food Chain. Prague, Perth: IPEN – Arnika – NTN. https://ipen.org/sites/default/files/documents/ipen-toxic-fly-ash-in-food-v2_3-en.pdf))
Exposure to these byproducts has significant health implications. Studies of fence line communities near waste incinerators have revealed terrible outcomes for those exposed to incinerator pollutants, including increased rates of preterm births, increased wheezing, headaches, stomach aches, and fatigue in schoolchildren, increased risk of miscarriages from exposure to particulate matter, increased risk of lymphoma due to dioxin emissions, and excess deaths due to stomach, liver, colon, and other cancers.((Tait, P. W., Brew, J., Che, A., Costanzo, A., Danyluk, A., Davis, M., … & Bowles, D. (2020). The health impacts of waste incineration: a systematic review. Australian and New Zealand Journal of Public Health, 44(1), 40-48. https://doi.org/10.1111/1753-6405.12939))((National Research Council. (2000). Waste incineration and public health. National Academy Press.))((Azoulay, D., Villa, P., Arellano, Y., Gordon, M. F., Moon, D., Miller, K. A., & Thompson, K. (2019). Plastic & Health: The Hidden Costs of a Plastic Planet. CIEL. https://www.ciel.org/reports/plastic-health-the-hidden-costs-of-a-plastic-planet-february-2019/))((The New School Tishman Environment and Design Center (2019). U.S. Solid Waste Incinerators: An Industry in Decline. https://grist.org/wp-content/uploads/2020/07/1ad71-cr_gaiareportfinal_05.21.pdf))((Garcia-Perez, J., Fernandez-Navarro, P., Castello, A., Lopez-Cime, M-F., Ramis, R., Boldo, E., & Lopez-Abene, G. (2013). Cancer mortality in towns in the vicinity of incinerators and installations for the recovery or disposal of hazardous waste. Environment International, 51, 31-44. https://doi.org/10.1016/j.envint.2012.10.003))((Ranzi, A., Fano, V., Erspamer, L., Lauriola, P., Perucci, C.A., & Forastiere, F. (2011). Mortality and morbidity among people living close to incinerators: a cohort study based on dispersion modeling for exposure assessment. Environmental Health, 10, 22-34. https://doi.org/10.1186/1476-069X-10-22)) Moreover, these impacts are often shouldered by marginalized communities that are disproportionately exposed to industrial pollution. In the US, as many as 8 out of 10 incinerators are sited in low-income communities or communities of color, often alongside other polluting industrial facilities.((The New School Tishman Environment and Design Center (2019). U.S. Solid Waste Incinerators: An Industry in Decline. https://grist.org/wp-content/uploads/2020/07/1ad71-cr_gaiareportfinal_05.21.pdf ))((Schwarz, L., Benmarhnia, T., & Laurian, L. (2015). Social inequalities related to hazardous incinerator emissions: An additional level of environmental injustice. Environmental Justice, 8(6), 213-219. https://doi.org/10.1089/env.2015.0022))((Martuzzi, M., Mitis, F., & Forastiere, F. (2010). Inequalities, inequities, environmental justice in waste management and health. European Journal of Public Health, 20(1), 21-26. https://doi.org/10.1093/eurpub/ckp216))((Baptista, A. I., & Amarnath, K. K. (2016). Garbage, Power, and Environmental Justice: The Clean Power Plan Rule. William. & Mary Environmental Law & Policy Review, 41(2), 403-433.))
Beyond being an environmental and health liability, incineration often fails to deliver its basic services of waste disposal and energy generation in a cost-effective manner. Incineration is the most expensive waste management strategy, with high upfront capital costs and continued high operational costs to cover pollution control, air quality monitoring, wastewater management, and ash disposal.((Moon, D. (2021). The High Cost of Waste Incineration. Global Alliance for Incinerator Alternatives. www.doi.org/10.46556/RPKY2826)) Waste-to-energy can cost as much as USD $190-1200 per tonne of waste handled per year, compared to landfill’s range of USD $5-50 per tonne per year.((Moon, D. (2021). The High Cost of Waste Incineration. Global Alliance for Incinerator Alternatives. www.doi.org/10.46556/RPKY2826))
Incineration is one of the most expensive ways to generate electricity, costing four times as much per unit of energy as solar or onshore wind, twice as much as natural gas, and 25% more than coal.((Moon, D. (2021). The High Cost of Waste Incineration. Global Alliance for Incinerator Alternatives. www.doi.org/10.46556/RPKY2826)) It’s also highly inefficient. After taking the embedded energy in incinerated waste into account, analysis shows that WTE actually wastes more energy than it produces.((Morris, J. (2005). Comparative LCAs for curbside recycling versus either landfilling or incineration with energy recovery (12 pp). The International Journal of Life Cycle Assessment, 10(4), 273-284. https://doi.org/10.1065/lca2004.09.180.10)) High costs and inefficiencies often lead to WTE facility closures, and can end up costing municipalities that use WTE considerable amounts to decommission and find waste management alternatives. Since 2000, 31 municipal solid waste incinerators in the US have closed, largely due to insufficient revenue to cover costs, and in some cases, cities have even been driven to bankruptcy by failed WTE projects.((The New School Tishman Environment and Design Center (2019). U.S. Solid Waste Incinerators: An Industry in Decline. https://grist.org/wp-content/uploads/2020/07/1ad71-cr_gaiareportfinal_05.21.pdf))((Tavernise, S. (2011, October 12). City Council in Harrisburg Files Petition of Bankruptcy. The New York Times. https://www.nytimes.com/2011/10/13/us/harrisburg-pennsylvania-files-for-bankruptcy.html )) In turn, these costs are assumed by the public through taxes and high garbage bills, further burdening the low-income communities that are often exposed to facility emissions as discussed above.
All in all, incineration’s environmental and health impacts create new problems for plastic waste management while failing to compete economically with other, less carbon-intensive waste management strategies or energy generation technologies. These factors, coupled with the technology’s reliance on plastic waste make it a poor tool for tackling the plastics crisis.