Ammonia is a carbon-free compound with the potential to replace conventional fossil fuels, helping to reduce carbon emissions and serving as a new source of clean energy. This study investigates a 660 MW coal-fired boiler using numerical simulation to evaluate combustion characteristics and pollutant emissions during co-firing with ammonia. For single-layer co-firing (ammonia injected into one of the five primary air nozzle layers), the optimal condition is 15% ammonia addition in the fourth layer, giving a furnace outlet oxygen concentration of about 3.2% and NOx emissions reduced to 120 ppm. For multi-layer co-firing (ammonia injected into all five layers), the 20% ammonia co-firing ratio yields the best overall performance, with a furnace temperature of approximately 1800 K, outlet oxygen of 3.3%, and NOx emissions of 5.3 ppm (volumetric concentration equivalent). The addition of ammonia delays the ignition point of the fuel mixture, resulting in a lower combustion temperature in the furnace. In regions with low oxygen content, ammonia and nitrogen oxides undergo complete reduction reactions, which lowers nitrogen oxide emissions. This process achieves combustion that is efficient, low-carbon, and low-pollution.
- Open Access
- Article
Combustion Characteristics of 660 MW Pulverized Coal Fired Boiler Co-Firing with Ammonia
- Chunxia Jia,
- Heyan Zhang,
- Rongting Yang,
- Hongpeng Liu *,
- Maozhan Cong,
- Jiawei Li,
- Xin Guo,
- Hong Qin,
- Qing Wang
Author Information
Received: 15 Jan 2026 | Revised: 05 Jun 2026 | Accepted: 12 Jun 2026 | Published: 15 Jun 2026
Abstract
Keywords
pulverized coal furnace | ammonia | combustion | temperature | NO
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