Continuing from our last blog post, which you can read here , we talked about what NOx is, why we need to control it and how each of us can help control it. As we all now know, industrial plants, and more specifically electrical power plants, generate a great deal of NOx , which contaminates our environment. There are several ways for these industrial plants to control their emissions, two of the ways are through the use of Selective Catalytic and Non Catalytic Reduction systems with a Urea Liquor mix (Diesel Exhaust Fluid at different concentrations). Different fuels need different NOx abatement techniques, for those that use Urea, we are here to shed some light.
What we know about SCR
- It is one of the most effective NOx abatement systems
- Has a higher initial cost
- Can achieve up to 94% DRE
What we know about SNCR
- Based on ionizing the Ammonia or Urea instead of using a catalyst
- Either urea or ammonia must be injected within a boiler or ducts where temperature is between 900 and 1100 degrees Celsius.
- Temperature has to be right, or ammonia will “slip through” or more NOx will be created than is reduced
- Can achieve up to 70% DRE
What is the difference between agricultural grade urea and NOXGUARD Industrial grade urea ( urea used for NOx control)?
Urea used for fertilizer is handled and stored differently than urea made into NOx control solution. High Quality dry or solution urea used in NOx control is kept in dedicated clean storage to ensure purity for both SCR and SNCR systems.
Why would a straight injection SNCR system need highly pure water or urea?
We know that the SCR system needs high purity water and urea, given the sensitivity of the catalyst bed. For the SNCR system if there happens to be any impurities in the solution they could be caked onto the nozzles and equipment in the exhaust zone. This can lead to clogging and could ultimately lead to costly damages in SNCR systems.
Why choose NOXGUARD for NOx Abatement?
NOXGUARD has spent many years on the technical process of making urea solution for NOx control in the automotive industry. Impure water and Ag-grade urea will not suffice in making urea NOx control solution. The water source must be removed of all impurities and de-ionized; if this is not done pollutants can damage the NOx control system. Fertilizer/feed grade urea can have contaminants, which will damage SNCR or SCR systems.
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