Guideline for regeneration of cation exchanger , anion exchanger and mixed bed

A) For Cation Bed
Make a regenerant solution ready by pouring 120 lit. of HCl into 100 Lt. of water.
REGENERANT QUANTITY : 120 ltrs. of 30% concentration commercial grade Hcl ) DILUTION WATER QUANTITY : 100 ltrs. of water
INJECTION TIME : 30 minutes
RINSING TIME : 10 minutes
B) For Anion Bed
Make the regenerant solution ready as per the quantities given below
REGENERANT QUANTITY : 18 kgs of NaoH (rayon grade)
DILUTION WATER QUANTITY : 150 ltrs of cation water
INJECTION TIME : 30 minutes.
RINSING TIME : 30 minutes.
C) For Mixed Bed
Make the regenerant solution ready as per the quantities given below.
REGENERANT QUANTITIES : 7.5 kg. of HCLcommercial grade (30% concentration) and 2.5 kg of NaoH (rayon grade).
DILUTION WATER QUANTITIES : 12 lts. of DM water for dilution of Hcl and 25 lts.of DM water for dilution of NaoH.
BACK WASH TIME : 10 minutes.
INJECTION TIME : 15 minutes (for HCL).
INJECTION TIME : 15 minutes (for NaoH).
RINSING TIME : 10 minutes (for both cation and anion).
AIR MIXING TIME : 15 minutes (0.5 kg/cm2 pressure).
FINAL RINSING TIME : 30 minutes.

OPERATION
1.0 For Cation Bed
1.1 While preparing a solution pour 120 Ltrs HCL into 100 Ltrs of water.
1.2 Open the valves CBV-6 & CBV-5 fully (CBV-1, CBV-2 and CBV-3 should be closed).
1.3 Open the valve CBV-4 such that the prepared solution is injected into the exchanger in 30 Minutes.
1.4 As soon as injection is over close CBV-5 and open CBV-4 fully so that the HCL solution remaining in the pipe line will be flushed out for 1 minute.
1.5 Close CBV-4 and CBV-6.
1.6 Open the CBV-1 and CBV-3 fully for 10 minutes (or)till pH comes to 2.5 to 3.5 with the help of pen type PHmeter.
1.7 As soon as pH comes within the range close CBV-3 and open CBV-2.

For Anion Beds
2.1 Open the valves ABV-6 and ABV-5 fully (ABV-1, ABV-2, ABV-3 should be closed.)
2.2 Open the valve ABV-4 such that the prepared solution is injected into the exchange in 30 minutes.
2.3 As soon as injection is over close ABV-5 and open ABV-4 fully so that the NaoH solution remaining in the pipe line will be flushed out for one minute.
2.4 Close ABV-4 and ABV-6.
2.5 Open ABV-1 and ABV-3 rinse it for 30 minutes (or) till conductivity comes to less than 20 ms /cm (or) till PH comes 8 to 10 with the help of pen type PH meter.
2.6 As soon as the conductivity comes to less than 10 ms/cm close ABV-3 and open ABV-2.
For Mixed Bed
3.1 Back Wash : Open MBV-3 partially and open MBV-4 fully so that the cation and anion resin beds remain separated (See through sight glass).
3.2 Soda Injection
a) Open the MBV-6 and MBV-7 fully.
b) Open the MBV-5 such that the prepared solution is injected into the bed within 15 minutes.
c) As soon as injection is over close MBV-6 and open MBV-5 fully and allow the NaoH solution in the pipe line to drain for 1minute and then close MBV-5.
3.3 Soda Rinse : Open MBV-1 and MBV-7 to rinse the anion resin for 10 minutes and close MBV-1 and MBV-7.
3.4 Acid Injection:
a) Open MBV-9 and MBV-10 fully.
b) Open MBV-8 such that the prepared solution is injected with in 15 minutes.
c) As soon as the injection is over close MBV-9 and open MBV-8 fully allow the HCL solution to drain for 1 minute after 1 minute close the MBV-8.
3.5 Acid Rinse: Open MBV-11 and MBV-10 and allow rinsing for 10 minutes and closing MBV- 10 and MBV-11.
3.6 Air Mixing : Open MBV-12 and MBV-4, the air pressure should be 0.5 Kg/sq.cm. for 15 minutes, see that proper mixing should takes place and close MBV-12 and MBV-4.
SHUT DOWN
Final Rinsing : Open MBV-1 and MBV-10 and allow the water to drain for 30minutes (or) while the conductivity comes below 01ms/cm (or) till PH comes 6-7 with the help of pen type PH meter, then close MBV-10 and open MBV-2 collect the water in the storage tank.

Abbrevations:
MBV - Mixed Bed Valves
ABV - Anion Bed Valves