Hi,
Hoping someone has some ideas.
I work for a utility company and we have two combined cycle combustion turbines utilizing ammonia as the primary reagent in our selective catalytic reduction (SCR) of NOx. Our ammonia system uses an ammonia vaporizer to convert 29% (by weight) aqueous ammonia to vapor before injecting it into our flue gas. A generic picture is attached.
The ammonia injection takes place from multiple branches at multiple elevations within the flue gas stream; to ensure equal flow through all branches, multiple differential pressure indicators (22 total) are utilized.
The differential pressure indicators are u-tube type manometers with a range of 0-17.5" WC with a 1.75 specific gravity (SG) indicating fluid. Expected pressure drop across the manometer is likely no higher than 0.5 PSIG. The ammonia vapor system operates at about 250-300 F and the manometer will pick up a portion of this temperature.
I have been tasked with finding a suitable (and of course less expensive) alternative to the 1.75 SG OEM solution, which is no longer available. We are looking for about a quart of indicating fluid solution (we can use a two fluid system if necessary) with SG of 1.75-1.90. Our guys will be draining the tuning system after each use.
Thus far, I have looked at sodium bromide, carbon tetrachloride, and a tetrabromoethane solution.
If anyone else has an idea, it would be greatly appreciated. Thanks again.
Edited by compjm, 20 April 2016 - 09:16 AM.