It sounds like the target pH ...
Published by Daniel Couton, Process and Environmental Chemist
It sounds like the target pH might be being continuously overshot and there could be several reasons for this. The most common reasons, in my experience are:
- the pH probe is located incorrectly and this sends the dosing system into a frenzy and/or
- the concentration of the dosing chemicals is too high to control the pH effectively (this is linked to your dosing pump).
You shouldn't have to add both NaOH and HCl to meet the target pH unless the pH of your feedwater is highly variable.
- Are you measuring pH inline or in the tank?
- Are you dosing inline or in the tank?
- What is the actual TDS/conductivity before and after?
- What concentration of NaOH are you dosing?
- What concentration of HCl are you dosing?
2 Comments
TDS > 2,400 mg/l at Treated water
Published by Panuwat Tohsakul
1 Comment
Thanks, what is the TDS in the feed water?
Published by Daniel Couton, Process and Environmental Chemist
The pH probe is located discharge nitrification recirculation pump and control pH at 6.8-7.0, Concentrate of HCL 35% and NaOH 50%wt. I think I will check at stroke dosing pump.
Published by Panuwat Tohsakul
1 Comment
OK great. Your chemicals are quite concentrated so adding only a small amount can result in a significant change in pH. What is the flow of the plant (m3/hr or L/hr)?
Published by Daniel Couton, Process and Environmental Chemist