Ammonium Hydroxide pumping problems
Ammonium Hydroxide pumping problems
(OP)
We are a biotech company with a ammonium hydroxide system. We continually have vapor lock problems that disrupt production. If someone has experience with this application, what would you suggest for improving the process?





RE: Ammonium Hydroxide pumping problems
Check with the mechanical engineer who sized the pump. If he is not available, then contact your pump vendor. It is not an unusual problem and is solvable.
Good luck
RE: Ammonium Hydroxide pumping problems
RE: Ammonium Hydroxide pumping problems
Aqueous ammonia is a particularly maddening beast because ammonia is simply not content to be dissolved into the aqueous phase. As a result, it will jump out at the earliest available opportunity and make your pump's life miserable in the process.
As with all situations that involve dissolved gasses, the vapor pressure of an aqueous ammonia solution is HIGHLY dependant on temperature (19% aqueous is bad, 29% is hella-worse). This is of particular importance in positive displacement pumps that recirculate the pumped fluid back to the suction in order to dissipate heat generation. Unfortunately, my experience has been that the actual amount of heat generated in a PD pump is all but impossible for we mortals to calculate because this calculation involves pump specific parameters that are not readily available.
Also, if your pumps are mag-drive then there is additional heat generated by those insidious eddy currents.
Also, if you have a high point pocket in your pump suction line then you are asking for trouble.
FYI, a plethora of aqueous ammonia information can be found here:
http://www.larocheind.com/Library/lqaa.htm
Good luck.