Selectrocide A New Way To Decontaminate Purified Water Systems

1. SelectrocideA New Way To Decontaminate Purified Water Systems Mark Algar | AB Scientific

2. What is Selectrocide? • Selectrocide is a product that can produce ultra pure chlorine dioxide at the point of use to specific required concentrations. • It is a convenient, simple to use, and offers you a new way to decontaminate your water systems.

3. What is Chlorine Dioxide? • Chlorine dioxide (ClO2) is not chlorine, sodium hypochlorite/bleach • It shares the name chlorine but its chemistry is very different. • It is not a chlorinating agent and does not form chlorinated organic bi-products • ClO2 is an oxidiser

4. What is Chlorine Dioxide? • Chlorine dioxide is a true gas • Its efficiency is not compromised when in solution • Chlorine for example disassociates in water to form hydrochloric acid and hypochlorus acid. Both of which are more corrosive and less efficient than Chlorine. • Chlorine dioxide remains chlorine dioxide

5. What is Chlorine Dioxide? • It has a low oxidative strength but high oxidative capacity

6. What is Chlorine Dioxide? • It will not react with Ammonia • It will not react with most organic compounds • It DOES react with many cellular constituents • It DOES react with the cell membrane • It DOES react with cellular proteins

7. What is Chlorine Dioxide? • Mode of action: • Oxidation of the cellular components • By removing electrons the cell membrane and protein structures are permanently altered • Rapid cell death • This multifaceted and simultaneous reaction means resistance development is impossible

8. What is Chlorine Dioxide? • Due to the lower oxidation potential of ClO2 its antimicrobial action is retained longer in the presence of other organic matter. Chemical Formula: ClO2 Molecular Weight: 67.45 g/mole Melting Point: -59⁰C Boiling Point: +11⁰C Density: 2.4 x air

9. Chlorine Dioxide Vs Biofilm • Highly soluble in water which gives excellent penetration • Low oxidation strength, but twice the capacity of chlorine. • This makes it very effective against biofilms • Other more reactive biocides are ‘wasted’ on the extracellular matter

10. Why is it a good biocide? • Potential health threats are only of an irritant nature at the concentration used in this application • ClO2 decays naturally leaving no visible or harmful residues.

11. Why is it a good biocide? • It is not a skin sensitizer • It is a deodoriser • Removes/lowers TOC in water systems • Neutral pH • Broad material compatibility – non corrosive

12. Material compatability • The greater the oxidation potential the greater the corrosion potential.

13. Material compatability Electronics Stainless Steel (304 & 316 series) Copper Anodized Aluminium Lexan Delrin Teflon Viton UHMWPE PVC Polystyrene Nylon PMMA Polyethylene Polypropylene ABS Epoxy Gasket materials HDPE/LDPE Polycarbonate Silicone EPDM Incompatible with some Urethanes

14. What are the alternatives? • Stabilised Chlorine Dioxide • Corrosive, low efficiency • Chlorine & Bleach • Chlorinated by products harmful to membranes • Corrosive • Difficult to rinse and remove • Ineffective against biofilms • Caustic Soda • Highly reactive & corrosive • Hazardous

15. What are the alternatives? • Formaldehyde • Almost banned from use • Carcinogenic • Leaves residues • Difficult to handle, use and clean up • Hydrogen peroxide • Can require equipment • Not as permeable • More dangerous to the operator

16. What are the alternatives? • Disinfection concentrations (ppm) required to achieve a 5 log reduction in bacteria in 60 seconds

17. What is the catch? • Generation of ClO2 is expensive, requires specialist equipment and can be dangerous • Stabilised ClO2 is not pure • It is not possible to store in pressurised containers Selectrocide is the first technology to allow the production of ultra-pure chlorine dioxide at the point of use without expensive equipment or harmful by products

18. The Selectrocide Solution

19. How to use in water systems

20. How to use in small water systems • Very simple – 2 products to choose from • 750A or 12G • Add 1 x 750A per 30L • Add 1 x 12G per 150-400L • Close all openings • Allow time for generation

21. How to use in small water systems • Circulate through system • Test concentration at port • Empty completely • Re-fill, circulate and empty completely • Test concentration at port

22. 132 CFU/ml NG NG Distribution Pump Multi-Media Filter Carbon Beds RO Prefilters RO Boost Pump Feed Water Storage Tanks Reverse Osmosis Modules Softener Mixed DI Beds How to use in production scale water systems UV UV Filter TNTC NG TNTC NG TNTC NG Distribution Loop After Decontamination NG = No Growth TNTC Before Decontamination TNTC = Too Numerous to Count

23. 132 CFU/ml NG NG Distribution Pump Multi-Media Filter Carbon Beds RO Prefilters RO Boost Pump Feed Water Storage Tanks Reverse Osmosis Modules Softener Mixed DI Beds How to use in production scale water systems UV UV Filter TNTC NG TNTC NG TNTC NG Distribution Loop After Decontamination NG = No Growth TNTC Before Decontamination TNTC = Too Numerous to Count

24. 132 CFU/ml NG NG Multi-Media Filter Carbon Beds RO Prefilters RO Boost Pump Distribution Pump Feed Water Storage Tanks Reverse Osmosis Modules Softener Mixed DI Beds How to use in production scale water systems UV Filter UV TNTC NG TNTC NG TNTC • Prior to decontamination the feed to the reservoirs is stopped and UV switched off. NG Distribution Loop After Decontamination NG = No Growth TNTC Before Decontamination TNTC = Too Numerous to Count

25. How to use in production scale water systems • The appropriate number of 12G sachets are added to the reservoirs to achieve 30-50ppm of chlorine dioxide within the whole system. • The system is left re-circulating and therefore equilibrium is achieved throughout the whole system. • After approximately 4 hours check the concentration of chlorine dioxide from a sample port on the return line.

26. How to use in production scale water systems • If 30ppm is achieved – open each valve and port on the system to allow ClO2 to make contact with all plumbing and valves. • Keep these ports open until the concentration of ClO2 exiting the port is the same as that of the system. Close valves. • Concentrations can be measure using a simple colorimeter or test strips. • Leave re-circulating over night.

27. How to use in production scale water systems • Because ClO2 is a gas at normal conditions even if liquid does not make contact with every surface, ClO2 still will.

28. How to use in production scale water systems • The following morning measure to concentration again to ensure the target concentration has been maintained overnight. • Remove sachets and drain the system fully. • >>>> • Re-fill the reservoir

29. 132 CFU/ml NG NG Distribution Pump Multi-Media Filter Carbon Beds RO Prefilters RO Boost Pump Feed Water Storage Tanks Reverse Osmosis Modules Softener Mixed DI Beds How to use in production scale water systems UV UV Filter TNTC NG TNTC NG TNTC NG Distribution Loop After Decontamination NG = No Growth TNTC Before Decontamination TNTC = Too Numerous to Count

30. How to use in production scale water systems • Reverse Osmosis systems can also be decontaminated by ClO2. • Because ClO2 does not ionize and exists as a gas in water it has the ability to pass through RO membranes • This makes it possible to decontaminate both the feed and permeate side of RO membranes simultaneously.

31. How to use in production scale water systems • There are 2 common methods of delivering a 50ppm concentration of ClO2 to the RO membrane. • A stock concentration is made and added via a dosing pump to achieve 50ppm. • A 50ppm solution is made and a self priming injection pump is used to feed chlorine dioxide through the RO membrane. • Temporary plumbing or valve settings may be required

32. How to use in production scale water systems • If possible drain the product side of the RO modules to minimise the dilution of ClO2 • Process control settings may need to be changed • Once the outlet and reject streams reach a concentration of 50ppm leave the system for 1 hour • Flush the system with water and test until <1ppm

33. How to use in production scale water systems • Return all temporary plumbing and settings to normal operation • Operate as normal • High conductivity in the feed or product stream should not be observed as ClO2 is uncharged and flushes quickly

34. How to use in production scale water systems

35. How to use in production scale water systems • Re-fill the reservoir • In this example the DI system was bypassed and so the main reservoir was filled with RO water quality for the initial rinse

36. How to use in production scale water systems • Start re-circulation from the reservoir, through the loop then to drain. Switch on UV • Test the ClO2 concentration at the drain • Once <1ppm is detected open all ports to flush them • Continue until the system is drained

37. How to use in production scale water systems • Refill the system fully and it is ready to use!

38. How to use in water systems • Used sachets can be disposed of in regular waste • Waste water can be sent to the regular drain • Personal Protective Equipment (PPE) Required • Eye protection • Gloves • Carbon filter mask (if likely to be exposed to gas in head space)

39. Summary • Excellent biocidal properties • Selectrocide is the first point of use technique that can generate ultra-pure chlorine dioxide without equipment. • It is NOT stabilised chlorine dioxide • Excellent material compatibility • Safe & easy to use • Does not pose environmental risks

40. Thank you for listening! Mark Algar | AB Scientific mark.algar@abscientific.com