[bold]Help!!![/bold]demin water unit
[bold]Help!!![/bold]demin water unit
(OP)
Do anybody know why does my demin water unit cannot reach pH 7? cause it only reach 5.
please i need a sugestion on how to increase pH in demin unit with an ion exchanger bed
please i need a sugestion on how to increase pH in demin unit with an ion exchanger bed





RE: [bold]Help!!![/bold]demin water unit
If the pH is measured by a pH probe do you have one specifically designed for low conductivity operation?
When does the low pH occur in the service cycle?
What type of anion resin are you using in your beds?
What is the demin water's condcutivity?
RE: [bold]Help!!![/bold]demin water unit
1.Type of demin. unit, cation, anion, or mixed bed?
2.Age of demin. unit and resins?
3.Regenerant chemicals used and consumptions?
4.Is this a new problem or has the pH been trending off?
5.Are you following the manufacturer's instructions?
6.What is the conductivity of the effluent?
RE: [bold]Help!!![/bold]demin water unit
RE: [bold]Help!!![/bold]demin water unit
oh yeah and the raw water we use are rain water that we collect from a dam so it's an acid water
RE: [bold]Help!!![/bold]demin water unit
Are you using HCl or H2SO4? Have you made sure that you are getting sufficient acid into the cation vessel? If you are then you need to make sure that you are getting good flow distribution during service and regenration.
Is there a break tank between the anion and MB. If there is you are likely getting enough CO2 absorption to shorten your MB runs unless you have a great excess of anion resin in the MB vessel.
The MB should be doing much better than 0.9 uS/cm, you should be seeing <0.1 uS/cm for most of the service run. Make sure that you are getting good resin bed separation before introduction of regenerants. Also, make sure you are getting the right quantity of regenerant in the vessel. starvation diets don't work on IX resins for long.
RE: [bold]Help!!![/bold]demin water unit
Gary Schreiber, CWS VI
The Purolite Co.
RE: [bold]Help!!![/bold]demin water unit
RE: [bold]Help!!![/bold]demin water unit
Your primary cation likely uses a 2 or 3 step dilution cycle to avoid CaSO4 precipitation. Your mixed bed likely requires 4% acid.
RE: [bold]Help!!![/bold]demin water unit
How long have you been operating?
Did you have the manufacturer's service engineer onsite during startup?
As a start, you should call the equipment manufacturer and have them out for a service call. The equipment (demin or instrumentation) is definitely not working properly and something like this is difficult to diagnose with short email messages.
RE: [bold]Help!!![/bold]demin water unit
oh yeah we've tried to inject TSP to this demin water for BFW but after the water became steam the pH is back to 5.4.
and one thing did i mention that the raw water we use? it's rain water that we collect by using dams.
thanks for your tips guys. i really appreciate a lot
RE: [bold]Help!!![/bold]demin water unit
Anion resin degrades over time and if you have not replaced the anion resin in the last 5 years, you need replacement of the resin. The cation resin has a longer life.
I still think that you should get a qualified service engineer from an equipment manufacturer to check your system out.