The factory I work at has a large flume system that contains sugar and organics. CaO is added to the flume to maintain a 12pH and keep bacterial activity to a minimum. In order to reduce the use of CaO I need to roughly calculate losses due to different mechanisms.
Currently the two main unknown losses are:
- Bacteria forming organic acids that neutralize the Ca(OH)2. This is a very big factor if pH is permitted to drop. It may also be a factor in flume side streams even when a high pH is maintained, but it is complex and I will put it in the "unknown loss category" for now.
- Atmospheric carbon dioxide entering solution and bonding with the Ca(OH)2 to form CaCO3. The flume has roughly 4000m^2 of surface area. There are also some areas of agitation and air entrapment that would take some more analysis to parameterize. This is the one I'm hoping to be able to calculate.
So here are my questions:
How do I calculate the rate Ca(OH)2 is being neutralized? (I know moles, units, and general chemistry, but now sure how to calculate reaction rates from partial pressures on this scale and geometry)
Is the amount of Ca(OH)2 being neutralized, proportional(linear, log, or otherwise) to pH? (Not sure if this is a 100% surface area relationship or if it depends on the amount of Ca(OH)2 in the water)