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Selective Non-Catalytic NOx
Reduction (SNCR) Systems

 

DNT has successfully executed over 50 design/supply/guarantee SNCR contracts on a broad range of process applications:  MSW Incinerators, Biomass Stoker Boilers, Biomass CFB's, Biomass BFB's,  Cement Kilns, Pulverized Coal, Medical Waste Incineration, etc.  The method can use either urea or ammonia, and we have provided a similar number of each.    

SNCR can continuously achieve 40-60% NOx reduction in Solid Fuel Stoker Applications and is the technology of choice to avoid the painful capital and operating costs of catalytic systems.  I combination with improved Overfire Air or Flue Gas Recirculation, 70-80% NOx reduction is being demonstrated in practice.
DNT knows where, how, and how much reagent to inject into your Process.  
With the correct type, number and location of injectors, DNT's system has superior chemical efficiency  - which means achieving your permit requirements at the lowest ammonia slip and  reagent consumption.

DNT can perform Computational Fluid Dynamic and Chemical Kinetic Modelling if needed.  However, most Biomass and MSW boilers need not bother . . .  DNT's experience is better than pretty graphs.


The liquid reagent is received, stored, and processed in "Standard" design modules, prefabricated to the maximum extent possible.  Provided with or without the PLC of your choice.  Simple, Industrial Grade and Efficient.
   
  The key component is the injection nozzle.  DNT's Version 4 is now in operation at several facilities - as part of DNT systems or OEM replacement.  The Version 4 injector doesn't clog internally, and no maintenance for months in brutal environments.  Three basic sizes depending upon liquid flow and pentration distance.  Auto-Retract design proven and available for applications with multiple operating zones.

DNT has provided an equal number of urea and ammonia units.  In most cases,
19 wt% Aqua Ammonia is preferred due to the lower annual cost of chemical, simpler design related to chemical temperature maintenance, better NOx reduction at a given stoichiometry, and no/lower formation of N2O.  Urea can be a good choice for smaller units with reasonable NOx reduction requirements.   The Total Installed Cost for the two options is approxiamtely the same.