Volume 1; Issue 6 June 16, 2001 Welcome to PuroNews ... - Purolite

Volume 1; Issue 6 June 16, 2001
Welcome to PuroNews
We strive to make this newsletter of high interest to our readers and welcome any
feedback or suggested articles and topics for inclusion in future editions. Please email
us at gschreiber@puroliteusa.com
A NEWSLETTER FOR THE INDEPENDENT CULLIGAN DEALER
UPCOMING EVENTS:
The annual Great Lakes WQA Convention will be held June 28 - 29 at the Troy Marriott
Hotel, Troy, Michigan. I will be manning our booth there and look forward to visiting with
any who attend. Their Golf Outing will be at 10:00 a.m. on June 28 with registration at
9:15 a.m. I'll be doing that also and will partake of the frustrations of knocking the little
white ball around the course much unlike Tiger Woods.
RESIN DEFOULING - DI APPLICATIONS: Many times we receive calls requesting
help with DI resin problems. More often than not the problems are diagnosed as "Fouled
Anion Resin". Prevention of Anion Resin Fouling is obviously the best way to of
handling defouling. Sometimes, in spite of your best efforts, fouling will occur. Hardness
fouling of Anion resin will occur if a Deionizer is overrun by the user. This exhausts the
Cation resin and means that the Anion resin will see hard water. Hardness fouling will
also occur in a Mixed Bed Deionizer if the feed water is not presoftened. With Mixed
Beds on hard water you can just assume the Anion resin is hardness fouled and treat
accordingly. Organic fouling is most applicable to Anion resin. It is very difficult to
organically foul a Cation resin. Other foulants such as oil, bacteria or algae or metals
like iron, copper, zinc, etc. can foul a Cation resin in a DI application. Resin fouling can
occur if the feed water analysis changes, operating conditions change, incorrect
regeneration procedures, mechanical malfunctions, or failing to operate the system
properly. We'll discuss fouling by resin category.
CATION: OIL FOULING - Oils can coat the resin beads and prevent ion exchange. Oil
fouling can be identified by a "rainbow" effect on the water or by testing a sample of the
water with flakes from a Camphor Stick. The Camphor Stick can be purchased at Drug
Stores. It comes in a small square block. Scraping off some flakes into a saucer of the
water from the DI tank and watching the action of the flakes will indicate possible oil
fouling. If the flakes spin in the water there is likely no oil present. If they lay there like
"dead ducks" then the water likely contains oil. Unless the resin is "heavily oil fouled"

you should be able to defoul it using a nonionic surfactant. First backwash and then
drain the unit. Fill it with a solution containing 0.1% of the surfactant. Soaking the resin
in that solution and if possible injecting compressed air for agitation for half an hour and
then thoroughly backwashing the unit and rinsing downflow until all foaming disappears
completely should defoul the resin. The resin should then be regenerated using normal
regeneration procedures. Some have found success using DAWN DISH DETERGENT
as the surfactant. Others have purchased a product call TRITON X100 from various
chemical suppliers. You can contact me for more information on that product.
BACTERIA or ALGAE FOULING - Peracetic Acid would be my first choice in
disinfecting resin contaminated with Bacteria or Algae. It is a derivative of Hydrogen
Peroxide. Using a Peracetic Acid solution of 0.2% for one hour followed by thorough
rinsing for about 45 minutes should do the job. Make up 1 Bed Volume (BV) of a
solution containing 0.2% Peracetic Acid. A BV is the equivalent of 7.5 gallons of solution
for each cubic foot of resin to be treated. Inject this at a flow rate of 5 BV/hr with
displacement to drain. When all has been injected, stop the procedure and allow the
resin to soak for one hour. Continue the displacement rinse for at least 60 minutes at 5
BV/hr followed by a fast rinse for 30 minutes. The resin should then be regenerated
using normal regeneration procedures.
Formaldehyde is another alternative. I am not fond of this since it can be hazardous to
deal with. Make up 3 BV of solution containing 0.5% Formaldehyde. Commercial
Formaldehyde (called Formalin) contains 40% Formaldehyde and should therefore be
diluted approximately 80 times. Inject 1 BV of the solution at a flow rate of 5 BV/hr
discharging to drain. If possible, drain down the unit to a level about 2 inches above the
resin surface. Inject a second BV and retain that in the resin for a period of at least 8
hours or preferably overnight. Flush the unit until no Formalhdehyde is detectable by
Schiffs Test. Regenerate the resin TWICE.
Sodium Hypochlorite is an alternative that can also be used. A 1% chlorine solution
should be used. The resin should be in the thoroughly exhausted form. This will prevent
production of chlorine gas. Make up 3 BV's of solution. The first bed volume should be
passed through the bed at the normal regeneration flow rate or about 4 BV/hr. The
second BV should be retained in the bed for no more than 2 hours. The third BV should
be passed through the bed at the same flow rate as the first. This should be followed by
a displacement rinse at about 4 BV/hr with softened water and then rinsed thoroughly to
drain. At least 8-10 BV's will be required. Test to insure all chlorine is removed. The
resin should then be TRIPLE regenerated. CAUTION: Suitable safety precautions
should be taken when using Sodium Hypochlorite and drains into which the
waste is to be discharged should be free from acids or other chemicals which
may react adversely with the discharge.
METALS FOULING - Normal regeneration procedure of Cation by HCl should remove
any metals fouling. However, a double dose regeneration is preferable if the metals
fouling is suspected.

ANION: HARDNESS FOULING: This will occur on any Anion resin exposed to hard
water. It can be seen in the backwashing by a white cloudy appearance to the
backwash water or tested for by testing a sample of the water for Hardness in the Anion
vessel. Hardness fouling can be removed by regenerating the Anion resin on the Cation
PE Regeneration station. CAUTION: The Anion resin must be totally exhausted
before the defouling with acid procedure is done. After the defouling procedure is
done the resin must have all acid totally rinsed out before the resin is then
regenerated. After the Cation regeneration of the Anion resin is done the Anion resin
should then be given a double dose Anion regeneration. Any anion resin that is part of a
Mixed Bed DI resin bed should be assumed to be Hardness fouled if the feed water is
not softened.
ORGANIC FOULING: This will typically occur with any Anion resin used on waters with
more than 1 ppm TOC. It can be seen in a dark brown color to the regenerant waste
water and sometimes even in a yellow to brown color in the backwash water. In
addition, Organic Fouling can be detected in symptoms of poor capacity, long rinse time
and high Silica leakage. There is a very large spectrum of Organics that can foul an
Anion resin. Proper pretreatment of the feed water to the Deionizer when the TOC
exceeds 1 ppm is the best prevention of Organic Fouling. This can be accomplished in
some cases with Activated Carbon as the pretreatment or by pretreating with an Anionic
Organic Scavenging Ion Exchange Resin.
The resin should be treated at the end of a normal exhaustion cycle. This is called a
Warm Brine Squeeze. 3 BV's of 10% brine containing 2% Caustic Soda should be
prepared. This solution should be a minimum of 95 degrees F. For a Type 1 Anion resin
the temperature can be as high as 140 degrees F. One BV should be introduced at a
flow rate of 2 BV's/hr followed by a second BV - this second BV should be retained in
the resin bed for at least 2 hours (longer if possible). Some agitation should be
employed periodically throughout that time. At the end of the retention time the 3d BV
should be passed through the bed at 1 BV/hr and then the resin thoroughly rinsed with
Decationized or Soft Water. The resin should then be regenerated by 2 complete
regeneration cycles.
IRON FOULING: Sometimes Organics have Iron bound into them which will cause Iron
Fouling of the Anion resin. If this is suspected then, prior to the Warm Brine Squeeze,
do a Hardness Defouling procedure as stated above. If Organic fouling is still expected,
then the Warm Brine Squeeze can be done.
NOTE: At the Purolite USA web site www.puroliteusa.com you can go to our
"LIBRARY" page on that site and download our bulletins "Fouling of IEX and
Cleaning" and "Organic Fouling of Anion Resins" for more information. Also on
that web site is a "BULLETIN BOARD" page. You can post any questions there
and we will reply. It is an interesting page with all of the questions and replies
permanently maintained.
Remember, Mixed Bed DI resins are just a mix of Cation and Anion resins. Separate
treatment for fouling is required. Also, remember that proper pretreatment and proper
operation of the Deionizer are critical to preventing resin fouling. Finally, without a

COMPLETE analysis of the water to be treated one cannot accurately predict capacity
and fouling potentials.
This ends this issue of PuroNews. If you know of anyone who does not receive
this but should, please either send me their email address or tell them to send me an
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address gschreiber@puroliteusa.comand type REMOVE in the subject line.
GARY SCHREIBER, CWS VI
The Purolite Company
CONTACT INFO:
Schreiber Phone: 1-800-834-8784 or 1-507-448-3560
Schreiber FAX: 1-507-448-3508
Schreiber CELL: 1-507-271-6866
Purolite USA Phone: 1-800-343-1500 or 1-610-668-9090
Purolite USA Email: gschreiber@puroliteusa.com
Purolite Global Web Site: www.purolite.com .
Visit these sites to get more answers to your resin application questions.
Purolite International Email: info.uk@purolite.com
Purolite International Phone: +44 1443 229334
Just Ask Purolite.