At present, the NOx in waste incineration flue gas control technology mainly include low NOx combustion control technology, selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR) technology. NO control technology relies mainly on the combustion process to take certain measures to reduce the emissions of NO concentration. SNCR technology is under the condition of without the use of catalyst, through within the chamber of a stove or furnace optimum temperature (850 ~ l050 ℃) injection reductant direct reduction NOx, common reductant for urea and NH3, denitrification efficiency is only about 40%.
In short, the burning of pollutants in flue gas composition is complicated, the current domestic waste incineration power plant more common combination of flue gas treatment process include "SNCR + semi-dry method + activated carbon injection + cloth bag dust collector" technology, can meet the current standards for pollutants discharge, but with the improvement of environment protection, this process remains to be further research. In addition, semi-dry method commonly used mechanical rotary atomizer is mainly rely on import, the problem of the high flue gas treatment costs, in the later research direction, can from the following several direction were discussed.
1) source control garbage processing, strengthen the garbage classification collection transport systems, containing metals and chlorine to minimize the waste into the incinerator, thus reducing the production of heavy metals and dioxins in the flue gas.
2) to strengthen comprehensive degradation, development of new equipment, such as the development of high efficiency bag filter, dust removal at the same time, effective degradation of dioxin and NOx, developing new SCR device, and degradation of dioxin and NOx, etc.
3) to develop a suitable alternative rotating twin fluid nozzle atomizer, reduce the investment cost.
4) in view of the incinerator flue gas characteristics, develop a reasonable combination of process (such as a dry, dry, dry and wet), select the appropriate deacidifying agent can effectively reduce the concentration of pollutants in flue gas.
5) SCR method currently used mainly platinum and palladium catalyst, and the activity of catalyst increases with the increase of metal content, high cost, thus developing economy applicable catalysts needs to be studied further.