NEDO and partners achieve 85% ammonia co‑firing in naphtha cracking furnace
- Test furnace reached 85% ammonia co-firing on a heat‑input basis across the entire furnace.
- Hearth burners operated at 100% ammonia while wall burners remained on off‑gas methane during the test.
- NOx emissions were confirmed comparable to existing commercial furnaces despite ammonia’s fuel‑derived NOx risk.
- Project runs FY2021–FY2030 (planned) with the target of achieving 100% ammonia firing and commercial application.
Project context
Under NEDO’s Green Innovation Fund project to develop carbon‑free heat sources for naphtha cracking furnaces, Toyo Engineering, Mitsui Chemicals, Maruzen Petrochemical and Sojitz Machinery have developed ammonia‑fired burner technology to reduce combustion CO2 from naphtha crackers. Ammonia emits no CO2 on combustion but presents challenges including lower laminar burning velocity and fuel‑derived NOx.
Technical development and test results
Two burner types were developed: hearth burners for primary heat input and wall burners to shape flames and temperature distribution. In a stepwise demonstration the hearth burners were run at 100% ammonia while wall burners were kept on off‑gas methane, yielding an overall ammonia co‑firing rate of 85% on a heat‑input basis across the test furnace. NOx emissions were confirmed to be comparable to those of existing commercial furnaces.
Next steps and timeline
The partners will apply ammonia firing to wall burners and aim for 100% ammonia combustion across the entire furnace, advancing development toward commercial‑scale naphtha cracking furnaces. The project period is FY2021–FY2030 (planned). As of August 2026 the 85% co‑firing rate was described by the participants as a world‑class level based on their survey of public information.
Source: TOYO
