Second Generation Advanced Reburning for High Efficiency NOx Control

Energy and Envirorurental Research Corporation (EER) is developing a family of high efficiency and low cost NOx control technologies for coal fired utility boilers based on Advanced Rebuming (AR), an integration of conventional reburning with injection of a nitrogen agent (N-agent) for enhanced NOx control. The second generation systems incorporate two improvements over conventional AR: • N-agent Promotion There are additives which considerably enhance the NOx control from N-agent injection. These promoters are water soluble inorganic salts which can be added to aqueous nitrogen agents. • N-agent Injection into the Reburning Zone In conventional AR, the N-agent is injected along with the overfire air. However, the N-agent can also be injected into the reburning zone. This allows two stages of N-agent injection for deeper NOx control. Experimental and kinetic modeling results on integrating these improvements with AR are presented. These results show that NOx control can be increased to over 90%. These second generation AR systems are intended for post-RACT applications in ozone non-attainment areas where NOx control in excess of 80% is required.