Cane Sugar Refining - Purolite

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Table 4: Regeneration Sequence
Cane Sugar Refining with Ion Exchange Resins
Operation Solution Flow Time Volume Temp Dose
Sweeten Off Condensate 2-4 BV/hr 30-60 min 1.5-2 BV 60-80˚ C
Chemical In 10% NaCl 1-2 60-90 2-3 60-80 200 gm
0.5% NaOH
NaCl/L+
10 gm
NaOH/L
Slow Rinse Condensate 1-2 45-60 1.5-2 60-80
Fast Rinse Condensate 10-20 15-30 3-5 60-80
Sweeten On Sugar Syrup 68˚ Bx 2-4 30-60 1-2 70-80
Service Sugar Syrup 68˚ Bx 2-4 70-80
An external backwash is recommended to remove fines and suspended solids when
pressure drop achieves 2 Kgf/cm² or 30 psi in the bed or during special cleaning.
Special Cleaning for Sugar Decolorization Resins
It is strongly recommended to use the procedure below for decolorization resins every
30 cycles or when an important drop in throughput is noticed.
It is very important that resin be regenerated prior to beginning this treatment.
Step 1: Prepare 2 BV solution with 6% HCl or 10% H 3 PO 4
Step 2: Pass half the volume of acid solution at a flow rate of 1 BV/h for one
hour downflow
Step 3: Introduce second half and keep for 2 hours in contact with resin. Injection of
air every 20 minutes assists in declumping
Step 4: Pass condensate or demineralized water at 3 BV/h downflow for 1 hour
Step 5: Rinse resin bed with condensate or demineralized water at 8 BV/h downflow
until pH = 7.0
After completing this procedure, perform a normal regeneration but with twice the
standard amount of NaOH in order to neutralize residual acid and the acid adsorbed
onto the small amount of weak base sites of the resin.
The acid cleaning should restore decolorization performance for an extended period
if the resin is in good shape. As the resin nears the end of its life, the acid cleaning will
provide a more temporary improvement in decolorization.