Design for denitration in small boilers
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I’m a complete novice; please give me some advice. It’s a 15-ton small boiler, with flue gas flow of 38,000. Denitration is achieved using SNCR technology with urea as the reagent, and there are 2 nozzles, each with a flow rate of 37 L/H. Should 4-mm-thick stainless steel pipes be sufficient for this application? Is there a big difference in the use of 304 and 316? The flow rate calculated is 0.08 m/s – is that a bit low? Is there a range for solution flow rate? 2. Use a metering pump; the height difference between the pump and the spray gun should be around 3 meters. The liquid pressure required at the spray gun is between 0.2 and 0.5. A pump with a head of 30 meters should be sufficient, right? The total length of the pipeline is about 50 meters; one section of it is in an inverted U shape and runs along the roof. It is said that the flow rate is less than 200 L/H, so a pulsation damper isn’t necessary. Should it be fine for my setup without one? 4. Is it a problem not to install a safety valve on the pipeline? 5. Instead of using a dissolution tank and a storage tank, can we simply use a tank with a diameter of 1.2 meters and a height of 2 meters for pouring in the material, stirring it, heating it, dissolving it, and storing it? Is that feasible? Looking forward to an answer, thank you
316L has better corrosion resistance than 304, and it is also more expensive. 310S is more resistant to high temperatures and corrosion than 316 and 304. The price is higher. Since SNCR systems operate at temperatures above 850 degrees, the use of 310S is more common in such cases. It’s normal for your stove to be too small and simplified. As long as it meets the standards, that’s fine. But don’t expect great results. The investment cost is right here
For small boilers, there’s no need to use SNCR for denitration; the oxidation method is better. It doesn’t require any modification to the boiler itself. What is used in SNCR – ammonia or urea? The cost is too high
For denitrification in small boilers, the carbon molecule gasification combustion technology can ensure compliance with emission standards. This is the technical capability for preventing pollution at the source of the vaporization and combustion of carbon molecules, as well as for reducing the amount of these elements.
Basically, a 304 stainless steel tube suitable for use in guns will suffice, fully meeting the requirements of your operating conditions
Acoustic soot blowers can be used for SCR denitration in boilers
Take a look at what type of metering pump you have chosen: hydraulic diaphragm or mechanical diaphragm. As far as I know, the hydraulic diaphragm comes equipped with an internal pressure relief function. It is recommended to add a safety valve to prevent pressure buildup in the pipeline from damaging the metering pump.