As a technique to reduce the level of NOx (nitrogen oxides) in boiler or furnace exhaust gases Selective Catalytic Reduction has been around for years, as has the use of ammonia as the reductant. The customer, who has been selling and servicing boilers and pumps for commercial and industrial applications for over 50 years, had been using a mass flow controller (MFC) which was not reliable or robust enough for the application and thus their customers were suffering from loss of ammonia measurement and control.
In the NOx reduction system the mass flow controllers are used to control the flow of anhydrous ammonia into the exhaust gas of a boiler or furnace where it is adsorbed onto a catalyst. The exhaust gas reacts with the catalyst and ammonia which converts the NOx into nitrogen and water.
There are very strict Federal and State air quality regulations that specify the allowable level of NOx which can released into the atmosphere and there can be very heavy fines if those levels are exceeded. The company needed to provide their customers with a reliable and robust solution.
The thru-flow nature of the CTA (Constant Temperature Anemometer) MASS-STREAM™ technology from Bronkhorst® is ideal to avoid clogging in potentially polluted industrial gas applications. The straight flow path and highly repeatable measurement and control capability combined with the robust IP65 housing allows the Mass-Stream to thrive in tough applications.
The customer began installing the Mass-Stream when old MFCs failed. The very positive experience with the Mass-Stream has lead them to proactively replace existing MFCs with the Mass-Stream in order to provide regulatory compliance and trouble-free operation for their customers.