The SNCR denitration technology of circulating fluidized bed boiler uses ammonia or urea as a reducing agent to spray the reducing agent into the flue gas, and then the reducing agent reacts with nitrogen oxides to generate nitrogen and water. In a suitable temperature range, the denitration efficiency can be More than 60%, the imported concentration is within 350mg/Nm3, and 100mg/Nm3 can be achieved. The investment cost is about 60% lower than the SCR under the same conditions.
The SNCR denitration technology, selective non-catalytic reduction technology, is a denitration method that does not require a catalyst. In the temperature range of 850 ° C ~ 1050 ° C, by spraying ammonia-containing reducing agent (such as ammonia water, urea solution) into the furnace, the NOX in the flue gas is reduced and removed to generate nitrogen and water to achieve the removal of NOX purpose. The industrial application of SNCR denitration technology began in the mid-1970s. At present, the total installed capacity of the SNCR denitration process in coal-fired power plants in the world is above 2GW.
In the mid-to-late 1990s, China began to apply SNCR denitration technology. Due to the presence of a high-temperature cyclone separator, the circulating fluidized bed provides a good temperature range, residence time and mixing conditions for the sufficient SNCR denitration reaction. It is an ideal SNCR denitration reaction application, and the denitration efficiency of SNCR technology is constant. Breakthroughs can reach 60% and up to 70% and above, which broadens the new way for the continued promotion of SNCR technology.
The technology can be used for denitrification of circulating fluidized bed, the investment cost is more than 60% lower than SCR technology, the denitration efficiency can reach more than 60%, the unit investment is roughly 15~35 yuan/kW; the operating cost is less than 0.4/kWh. Economically and effectively solve the problem of NOx emission pollution in circulating fluidized beds and meet emission standards.