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Ban on landfilling household waste puts spotlight on cement kilns

Published: 03 Feb. 2026, 00:04

Kim Dong-chan

The author is a research fellow at the Sejong Institute of Science and Technology and former director at the Korea Institute of Energy Research.

One month has passed since direct landfilling of household waste was fully banned in the greater Seoul area on Jan. 1. Starting with Seoul, Incheon and Gyeonggi, the ban will be expanded nationwide from 2030. Under the Waste Management Act, responsibility for treating household waste lies with local governments, while business waste is handled by the generator. Household waste is sorted into food waste, recyclables, volume based trash bags and other items, with waste in standard bags designated for incineration.

The Sudokwon landfill site, where direct landfilling will be banned starting in 2026. [SUDOKWON LANDFILL SITE MANAGEMENT CORP.]

In Seoul, about 3,200 tons of incinerable waste are generated daily, of which roughly 2,200 tons are treated at the city’s four incinerators. The remaining 1,000 tons had long been sent to the Sudokwon landfill without incineration. Ahead of the ban, Seoul pushed to build and expand an incinerator in Mapo but faced opposition from residents and some politicians. Incheon and Gyeonggi also planned two and four new incinerators, respectively, but met similar resistance.

Some metropolitan governments increased private outsourcing before the ban, yet this approach has limits. Costs rise, stable long term treatment is uncertain and heat recovery efficiency remains low. Since the ban took effect, one Seoul district has transported waste as far as 150 kilometers (93 miles) to South Chungcheong. Residents in the central region, long a destination for metropolitan waste, have voiced growing opposition.

With landfilling banned and outsourcing increasingly difficult, an alternative is urgently needed. This author proposes cement kilns used in cement manufacturing as a practical option. Major European countries including Germany, France and Italy already replace more than half of their bituminous coal with combustible waste in cement kilns. Beyond Europe, the United States and Japan also use waste as fuel, while several Southeast Asian nations are turning to kilns to cope with rising waste volumes.

Korea’s well-established waste separation system makes combustible household waste suitable as a coal substitute in cement kilns. Domestic cement plants are clustered in Jecheon and Danyang in North Chungcheong and in Yeongwol, Samcheok and Donghae in Gangwon, about 150 to 200 kilometers from the capital region by highway. In Samcheok and Donghae, plants already burn household waste as a substitute for coal with stable results.

Local governments collect standard bag waste, conduct pretreatment such as shredding and sorting and transport combustible material to cement plants for use as alternative fuel. Cement kilns offer environmental advantages over conventional incinerators. Incinerating household waste typically leaves about 20 percent ash that requires disposal. By contrast, kilns measuring 70 to 100 meters (230 to 328 feet) heat raw materials at around 1,500 degrees Celsius (2,730 degrees Fahrenheit) for 30 to 60 minutes, achieving complete combustion without residual ash.

Ash and metals melt and are absorbed into clinker, the cement intermediate. Dioxins, a concern in incineration, do not form in cement kilns, and leaching tests show no release of heavy metals. Using waste in kilns can reduce fine dust emissions, cut greenhouse gases and contribute to carbon neutrality while improving resource circulation and energy recovery.

A typical cement kiln at a cement manufacturing plant. Stretching up to 100 meters (328 feet) in length, the kiln heats raw materials such as limestone to temperatures of around 1,500 degrees Celsius (2,730 degrees Fahrenheit) using fuels including bituminous coal. [WIKIPEDIA]

The approach also extends landfill life and avoids conflicts over building new incinerators. Korea produces about 50 million tons of cement annually, and each ton requires roughly 0.1 ton of coal. Replacing coal with household waste lowers fuel costs for cement makers, creating a win-win outcome.

Realizing this option requires close cooperation between local governments and cement companies. In Samcheok and Donghae, municipalities collect and pretreat waste before transporting it to nearby plants, with transport handled by private contractors at local expense. To scale up kiln use nationwide, the Ministry of Climate, Energy and Environment should act as an intermediary and swiftly improve regulations to support cooperation.

Clear standards on waste quality, emissions monitoring, cost sharing and public communication would help build trust, ease local opposition and ensure that the ban on landfilling leads to a durable, environmentally sound waste management system.

This article was originally written in Korean and translated by a bilingual reporter with the help of generative AI tools. It was then edited by a native English-speaking editor. All AI-assisted translations are reviewed and refined by our newsroom.