1. 1
Physical Activity and
Leisure Management Ltd
POOL PLANT OPERATIONS
INFORMATION UPDATE SEMINAR
(on-line option)
1Carlton Associates Ltd (c) 2013

2. 2
Physical Activity and
Leisure Management Ltd
Module 3
Current Trends in Filtration and
Mechanical Services
2Carlton Associates Ltd (c) 2013

3. 33Carlton Associates Ltd (c) 2013
This module explores alternative
Filter Media; automated
backwashing and recommended
settling periods after backwashing.
In this Module we will be focusing on:

4. 4
• What is Happening to our
Mechanical Systems
• Link Between Backwashing, Filter
Efficiency and Cryptosporidiosis
• Coagulation
• Backwashing Regimes
• Use of Ultraviolet Radiation

5. 5
5
What’s happening to our
mechanical systems?
 Not very exciting, as these are not always in
areas that are seen by the swimmers.
 Without good management of mechanical
systems, there wouldn’t be such good quality of
customer provision.
 So, do we carry out preventative work, or do we
wait for something to happen?

6. 6
6
This can’t be right ………….. can it??
6

7. 7
7
ANTI-VORTEX OUTLET GRILLES
……… are now a requirement, if there is a risk
of vacuum formation.
Courtesy of Sterling Hydrotech Ltd

8. 8
8
“MUDBALLING” INSIDE A FILTER

9. 9
9
Replacement Filter Media
Imploded Glass Media
Leighton Buzzard
Sand Media
9

10. 10
THE LINK BETWEEN BACKWASHING; FILTER
EFFICIENCY AND CRYPTOSPORIDIOSIS
Unless Ultra-Violet Light or Ozone are used,
the presence of the Cryptosporidium
Oocyst, can only be trapped within the filter
media, and then usually only if a coagulant
is being used.
If the processes used are inefficient, then
the risk of cryptosporidium in the pool is
increased.

11. 11
11
Coagulation:
A filter type WITHOUT the
addition of a coagulant has the
ability to filter particles down
to a particular size;
approximately 8 microns.
As a rule of thumb:
• Salt 100 microns
• Talcum powder 8 microns
• Cryptosporidium oocysts 5 microns
• Bacteria 1–5 microns
A filter type WITH the addition of a coagulant can
bind together these microscopic particles, and
form, them into a size that CAN be held within
the filter bed.

12. 12
BACKWASHING REGIMES
 The process of backwashing fluidises the filter
bed, as the compressed media is broken up by
reversing the flow of water.
 Filtration is most efficient and effective when
the filter media is compressed.
 It can take up to 4 hours for the filter media to
regain its compression, and therefore its
efficiency, This process is referred to as
RIPENING.

13. 13
BACKWASHING REGIMES
 Consequently, during the ripening period, the
filter media is less efficient than it should be,
and this could place the swimmers at risk of
infection, if particles are being removed .
 Backwashing should therefore be carried out
when there is at least 4 hours of non-use
programmed after the process is complete.
 For many swimming pools, this will mean that
backwashing should be carried out at the end
of the operational day..

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14
ULTRAVIOLET
RADIATION

15. 15
15
Swimming Pool
Balance
Tank
Strainers
Circulating
Pump
Chemical
Measurement
Coagulant
Dosing
Medium Rate
Sand Filter
Heat
Exchanger
Stabiliser
Injection
Point
Disinfectant
Injection
Point
Ultra Violet Light Unit
ULTRA VIOLET LIGHT IN SWIMMING POOLS

16. How does it work?
 Pool water is still filtered, but is then pass through a sealed
stainless steel unit that houses the UV lamp.
 The UV rays react with all bacteria, as well as chemicals that
have been introduced into the pool water.
 Therefore the outlet water is free from chemicals and
bacteria, making it taste-free, smell-free, and very attractive
to look at.
 However, there is now a need to introduce low quantities of a
hypochlorite disinfectant to react with pollution in the pool,
before it is passed through the UV system. The Free
Chlorine level would normally be between 0.5mg/l and
0.8mg/l
16

17. 17

18. Carlton Associates Ltd (c) 2013
That is the end of Module 3
What you need to do now:
1. Return to the course page
2. Download the module update notes and save them
on your computer
3. Read through the notes
4. Print out the notes and insert them in your manual

19. Carlton Associates Ltd (c) 2013
End of Module 3 Presentation