1. Clean Water Treatment
Wastewater treatment

3. Clean Water Treatment
Wastewater treatment

4. About Dryden Aqua
Started trading 1984, focus molecular sieve ion exchange filtration
Primarily a research and development company, initial focus, water treatment in aquaculture & aquarium systems
New products had to be developed to try and resolve water treatment issues. One of our main products is AFM (Active Filter Media)
Dryden Aqua became a manufacturing company
Products and technology now applied to;
Aquaculture & Public aquaria
Swimming pools
Landfill leachate
Drinking water , surface, borehole and ground water
Pre-treatment prior to UF ultra filtration, and replacement of UF
Pre-treatment prior to RO membranes for desalination
Part of the treatment system in high purity water for semi-conductor manufacture

5. AFM is the recommended filter media for all public aquaria, aquatic mammals and zoological parks

6. 40,000 AFM systems installed in Europe.
AFM is the leading manufactured filtration media for the industry.

7. Dryden Aqua wins top award in Dubai October 2012
Dubai Channel 1 News

9. Activated sludge fine bubble diffused SBR system supplied to Saudi Arabia for the city of Medina, AFM filtration can be used on the discharge from the system to provide class 1 irrigation water.

10. FP7 Research Eco-India, drinking water treatment for India, arsenic, flouride, iron and biosecurity

11. Research and Ethics
Eco-India and FP7 research project to remove arsenic
Scottish Government survey of pool industry to quantify environmental status of the industry
Nation Health Service collaborative project to determine the toxicity of disinfection by-products
Technology Strategy Board of the UK, development of zero waste, water treatment strategy
Scottish Government Hydro-Nation initiative

12. AFM filters getting ready for dispatch, from
Dryen Aqua warehouse and AFM production facilities in the back-ground

13. Direct replacement for sand in all types of sand filters, for clean water and waste water.

14. Wastewater AFM mechanical filtration tertiary treatment

15. Wastewater tertiary treatment
AFM may be used in existing pressure sand filters or rapid gravity filters
There is no requirement to use moving bed filters, but AFM can also be used in moving bed filters to improve performance
Bed depth 300mm to 1200mm
Hydraulic loading, relates to solids load, usually around 5 m/hr, when solids are over 50mg/l. Under 50 mg/l SS, flows can be increase to 10 m/hr
Back-wash at 55 m/hr after air scour
AFM media will last for the life of the filters. Should never need to be changed.

16. AFM is being used to treat landfill leachate
SBR no sedimentation, AFM solids load, approx 200 mg/l. Product water After AFM < less that 20 mg/l
Other waste water applications
municipal waste water
brewery effluent, yeast control
farm / agricultural waste
effluent from anaerobic digesters
Industrial waste water; circuit board manufactures, chemical industry, oil platforms
Effective for hydrocarbon polishing, and heavy metal removal

17. Wastewater after humus tanks from fixed film biofilters or activated sludge
Before & after AFM filtration full scale installation… solids 80mg/l down to <5 mg/l using a pressure AFM filter, single pass no flocculation

18. AFM performance for the tertiary treatment of sewage effluent compared against different technologies Independent tests conducted by Spanish Water Company and reported in Technology del Agua , December 2009, page 47.
TYPE OF FILTER
SS. (mg/l)
Performance   %
 Turbidity ntu
bacteria
Velocity
inlet
outlet
inlet 
m3/m2/h
RGF sand filter with sand
7.14
2.2 69
3.5
2.23 36 46
1.2
Pressure filter with sand
8.18
3.82 53
5.87
4.76 18
22311
18023 19
4.96
Moving bed sand filter with sand
7.08
2.13
1.79 16
14067
10307 26
5.4
Drum filter 10 micron
14.66
7.33 50
7.16
3.88 45
56712
38460 32
3.23
Disc Filter  
10 micron
5.6
3.1 44
2.22
2.06 7
30450
21138 30
2.12
Ring Filter 10 micron
7.41
3.98
3.01
3.17
9447
7761 17
2.5
AFM®  Pressure filter
10.60
0.89
96%
2.98
0.24
92 %
23000
10000
58 %
3.59
AFM media in a pressure filter out-performed all other technologies, some of which were 10 times the cost

19. comparative evaluation of a high quality
Tertiary treatment of
sewage effluent
comparative evaluation of a high quality
Sand
against
AFM
using Gravity Sand filters independently certified under identical conditions

20. AFM Run-phase & back-wash profile Tertiary treatment using Rapid Gravity Sand filter
Channelling through bed
The graph shows the build up of pressure in the Sand filter followed by the back-wash. Run phase performance & back-wash frequency is variable. Periods where most of the water channels through the sand bed are self evident.

21. Run-phase & back-wash profile Tertiary treatment using Rapid Gravity AFM filter.
AFM filter media, run phase performance and back-wash frequency. Same run phase duration between a back-wash, no by-passing or channelling of waste water through the bed, stable & predictable effluent quality

22. AFM removes chemicals
AFM can perform well to remove chemicals such as ferric, manganese, TBT, copper, mercury, arsenic and PCB`s
Works effluent
AFM product water
AFM back-wash
4.6
<3.8
6.3
4.5
11.1
5.2
4.0
10.4
6.1
9.9
TBT concentrations ug/l, from a working WWT systems.
BioActive chemicals are link to causing damage to the marine ecosystem and impact on climate change.

23. Clean Water Treatment AFM mechanical filtration of drinking water
AFM is certified under Reg 31, it is the only filter media that is certified

24. Africa Drinking water before AFM after AFM
AFM is used in gravity flow system as well as pressure filters.
Bed depth 1200 to 1400mm
Run phase water flow <10m/hr
Air purge 55 to 100m/hr
Back-wash at >45 m/hr
AFM in simple gravity flow filters with no pre coagulation or flocculation used in Africa to produce clean water with a turbidity less than 0.5 ntu
AFM is used as a pre-treatment for RO and UF membranes. Full scale trials in progress to compare AFM against UF as primary drinking water treatment process in SE Asia
Africa

25. Filtration AFM verses sand filtration
Trials conducted on parallel systems with AFM and Leighton Buzzard Sand
What goes into a filter must come out in the back-wash The graph opposite is the back-wash profile for identical sand and AFM filters after 10 weeks. The profile shows that 30% more solids are back-washed out of the AFM. 30% more solids have there been removed during the run phase AFM performance is maintained while sand filters continue deteriorate with time.
A high percentage of the chlorine is actually consumed by the sand filters, and changing to new sand can dramatically reduce the chlorine demand of the filter.
A key point is
that the more chlorine that is consumed in oxidation of the alginates and bacterial cell biomass, the more volatile chlorine and combined chlorine compounds produced, this is a straight stoichiometric equation
Research supported by the European Commission over the last 5 years by Professor Alfred Bernard from the Catholic University in Brussels has shown, that there is a potentially serious issue with a link between high levels of volatile chlorine compounds in swimming pools and respiratory disorders such as asthma in children.
The link hasn’t been categorically proved, but it is perhaps best to err on the side of caution, and give serious consideration to this point.
Data from trials conducted by Suez Lyonnaise des Eaux
30% improvement after 10 weeks, 50% after 52 weeks.

26. Bacteria levels before and after sand and AFM
Plate count at 22 deg C. The linear trend line shows a 50% performance benefit over sand.
Plate count at 37 deg C confirm bacteria levels from AFM are half the level from sand filters.
The data confirms the bio-instability of sand filters, and due to transient worm-hole channelling they may occasionally discharge into the product water. This does not happen with AFM
The above trials were conducted with parallel filters in Scotland operating on a drinking water treatment facility. Data was collected and analysed by Scottish Water.

27. AFM is an active filter media Adsorption
Sand generates dissolved organic matter (DOC) through autotrophic bacterial cell growth
Hydrophilic surface with a negative Zeta potential of AFM adsorbs small particles and dissolved organic molecules from water.
Major reduction in DOC and this is without coagulation
DOC levels approx 50% lower after AFM
Tests conducted by Suez Lyonnaise des Eaux

28. Iron & Manganese levels before and after sand and AFM
Iron levels, linear trend line confirms AFM performance is improving, sand performance is deteriorating over time. AFM performance twice as good as sand.
Manganese linear trend line confirms AFM 400% better performance than sand.
The data confirms the bio-instability of sand filters, and due to transient worm-hole channelling they may occasionally discharge iron and manganese back into the water. Again this this does not happen with AFM
The above trials were conducted with parallel filters in Scotland operating on a drinking water treatment facility. Data was collected and analysed by a water company.

29. Autotrophic bacteria growth on sand
Autotrophic nitrifying bacteria rapidly become established on sand
The autotrophs increase the suspend solids as well as DOC level in the product water by converting inorganic carbon to organic carbon.
The extracellular alginate excreted by bacteria form worm holes and coagulation of sand.
AFM resists biofouling and stays clean
The above two graphs show that the sand is becoming a biofilter as indicated by the reduced ammonium and high nitrite levels. Test conducted by Scottish Water.

30. Biofouling of sand and AFM
Electron micro graphs of sand and AFM
Sand has 100% bacteria coverage after 3 days in a drinking water filter
AFM stays free of biofilm, even after 5 years in sewage effluent
Alginates excreted by bacteria coagulate the sand and cause wormhole channeling.
New sand
Used sand
New AFM
Used AFM

31. Performance AFM vs Sand
Parameter
sand
AFM
comments
Solids removal
Performance in terms of solids removed, 25% to 50% better than sand.
Bacteria levels
AFM will remove 100% more bacteria from the water than sand
Iron
AFM is very good at removing iron and manganese, due to surface –ve charge
Manganese
DOC
Sand can generate organic matter (clean water), AFM will remove organic matter
Particle size
10-15
< 5 um
AFM will remove most particles down to 5 micron, but also many sub-micron and dissolved components by surface adsorption
Biofilter capacity
AFM does not become a biofilter, not subjected bio-mechanical coagulation and worm-hole channelling

32. Bacteria levels on sand and AFM transient worm holes
Sand filters are biological, bio-mechanical instability results in media coagulation, transient worm hole channel and discharge of solids into the product water
AFM is electro-mechanical, media does not suffer from bacterial coagulation so no channeling of water through the filter bed.
Total colony count ( aerobic) at 37 deg C, on 5 grams of filter media
AFM 18
sand
3,600,000
Media samples were taken just prior to a back-wash at a depth of 200mm into the bed, and 500 mm from the side of the filter.
Bacterial levels on AFM and sand after 3 months in a clean water filter. The Table is certified data showing total bacterial levels of 3.6 million with sand, and essentially zero with AFM.

33. technical specification & mechanism How does AFM work
technical specification & mechanism How does AFM work? For clean water and waste water applications

34. AFM active filter media, performance summary
Typically improves performance by 30% to 50% in terms of solids removed for both waste water and clean water applications. AFM does not need to be replaced, the media may be used for the life of the filter, and can be recycled and used again. AFM does not bio-coagulate or experience worm-hole channelling. Performance is stable and predictable AFM® is certified under Regulation 31 of the UK Drinking Water inspectorate, AFM® is compliance with European Water Directive (98/83/EC) & (80/778/EEC).

35. O2 + H20 3O + OH Some technical aspects of AFM.. catalysis
Manufactured by Dryden Aqua in Scotland from reprocessed glass and glass manufactured to Dryden Aqua specifications.
The glass is reduced to a precise particle size distribution and shape to maximise the hydraulic flow characteristics and mechanical filtration performance.
The raw material is chemically processed to open up the aluminosilcate atomic lattice and activate the surface physio-chemistry.
Catalytic reactions
AFM catalysis
O2 + H O + OH
Water containing oxygen to free radicals by surface
catalytic reactions
The free radicals help prevent biofouling and will cause some oxidation of dissolved organic matter and heavy metals and metaloids. Dissolved oxygen levels must be above 2mg/l for the reactions to proceed

36. Some technical aspects of AFM…surface charge
AFM mechanically removes most particles down to 5 microns.
Sand surface area, approx 3000m2/tonne, AFM surface area >1,000,000 m2/tonne
The high surface negative charge potential helps to adsorb micron and sub-micron particles as well as some dissolved organics
Works synergistically with +ve charged cationic flocculants and polymers
AFM rejects bacteria growth and worm-hole channelling
-ve charge AFM surface
stern layer (slip zone) predominantly divalent and trivalent cations
Anion diffuse layer sulphate and bicarbonates
Zeta –ve potential
+ve cationic flocculated solids
+ve charge coagulated and polar & dipolar dissolved organics
Zeta Potential reactions
on the surface of AFM and the behaviour of +ve and –ve ions as well as sub-micron particles and dissolved organics.

37. Cost benefit analysis
AFM is around 2 to 3 x the cost of sand, however we are already dealing with a relatively low cost product.
AFM has been confirmed to work a great deal better than sand, and will give a return in capital out of revenue savings measured in months through savings in;
a. water; back wash water reduced by up to 50%
b. energy; increased run phase and reduced back-wash could give 15% savings
C. chemicals; reduced chemical consumption, chlorine, ammonium & flocculants
d. filter media; no requirement to replace AFM for the life of the filter

38. Performance summary? Wastewater Clean water Performance advantage
Suspended solids
100 to 400%
COD/BOD/TOC
200%
Turbidity
100% to 400%
Ammonium
No change with AFM
Bacteria TTC
50% reduction
THMs
50% to 90% reduction
Back-wash profile
Used to check performance

39. Dryden Aqua aeruginosa Tel +44 (0) 18758 22222 Fax +44 (0) 18758 22229
Dryden Aqua LTD Butlerfield Bonnyrigg Edinburgh EH19 3JQ Scotland. UK
aeruginosa
Tel +44 (0)
Fax +44 (0)

40. Annex Bacteria analytical report Spanish waste water reports
AFM back-wash video
Scottish Water recommendations
Certification under UK regulations Reg 31 for drinking water. AFM is also compliant with NSF Reg 61. UK regulations are much more strict than NSF.

41. Faecal coliforms cfu/100ml
Bacterial analysis report
Filter media samples taken from a swimming pool water treatment system, free chlorine level 0.5 to 1.5mg/l, pH 7.2 to 7.4 at 28 deg C
Sample
Enterococci cfu/100ml
Faecal coliforms cfu/100ml
P. aeruginosa
cfu/100ml
S. aureus
cfu/10ml
37 degC
cfu/ml
Silica sand
<1
3,600,000
AFM 18
Standard methods of water analysis 20th edition 1998
9230C
9222D
9213E
9213B
9215B
Aerobic Plate Count
Client
Jonkers filtration P.O Box 708, Kumeu
New Zealand
Date received 22/07/04
Dated completed 29/07/04
Laboratory
SGS New Zealand Ltd.
Analyst name Marnie Sleeman NZCS
Laboratory Number
Filter media sample bacteriological analysis.

42. Spanish water company reports may be downloaded at the following link;
Click here
French NGO reports AFM twice as good as the best available crushed glass

43. AFM back-wash video

44. Dear Sir/Madam TO WHOM IT MAY CONCERN
I wish to confirm that Scottish Water has used AFM solutions and is in the process of developing a much closer working relationship with Dryden Aqua.  
Scottish Water tested AFM on-line for approximately 1 year in The results demonstrated significant performance advantage over sand in relation to suspended solids/iron removal and process efficiencies. I can also confirm that Scottish Water has been using AFM for targeted effluent treatment for some 14 years with considerable success in the removal of solids and BOD reduction.
Scottish Water's newly formed Research and Innovation team will, during 2012, commence a strategic research program into filter media and the wider water treatment process in order to demonstrate the performance of the media across Scotland - ensuring that the results are captured and communicated across our asset base. We fully expect the results to be repeated - leading to a wider programme of engagement and adoption with of AFM. 
Yours faithfully
Mark Haffey R&D Technical Leader, Technology & Innovation
Scottish Water - Always Serving Scotland
Scottish Water