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Oxidizing Biocide with function of slime prevention & removal

Oxidizing Biocide with function of slime prevention & removal. Jan 2013 Acculab . NaOCl + Stabilizer. NaBr. HOBr . Bacteria. ☞ Free HOBr generation mechanism of Justeq07. Stabilized chlorine + Br - → HOBr.

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Oxidizing Biocide with function of slime prevention & removal

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  1. Oxidizing Biocide with function of slime prevention & removal Jan 2013 Acculab

  2. NaOCl + Stabilizer NaBr HOBr Bacteria ☞ Free HOBr generation mechanism of Justeq07 Stabilized chlorine + Br- → HOBr - Steady conversion of Stabilized Chlorine and Bromide to free HOBr in process waters - Oxidation of bromide only occurs in situ (pH 5-9)

  3. Biocides for Cooling Water Justeq 07: stabilized chlorine/bromide ion General biocide usage of standard cooling tower NaOCl solution (~12%) is used as oxidizing biocide for cooling water. In order to complement NaOCl, non-oxidizing biocide may be used every two week.

  4. (A-1) Chlorine emission: Hypohalous acid and haloamine flashoff in industrial evaporative cooling systems

  5. (A-1-1) Speciation of Cl2, HOCl and OCl- as a function of pH

  6. (A-1-2) The speciation as a function of pH using values for K1 = 3.9x10-4 & K2= 2.9x10-8 at 25℃

  7. (A-2) Case studies : Amounts of hypochlorous acid flushoff by using standard cooling water systems at pH 8.5 ☞ Total usage of halogen can be reduced up to 1/5~1/10

  8. (A-3) Relative AOX formation in cooling tower by halogen biocides AOX: Absorbable Organic Halides: For environmental protection reasons, the AOX value must be monitored at all times. A cooling cycle operating with Justeq07 shows much lower AOX values than a cycle operated with chlorine or bromine

  9. (B-1) Steps in biofilm development 1) Surface conditioning • - Almost immediately a organic layer deposits • on the water/solid interface • - Conditioning layers neutralize excessive surface charge • & surface free energy • The absorbed organic molecules often serve as a nutrient source • for bacteria 2) Adhesion of pioneer bacteria • Some of the planktonic (free-floating) bacteria will approach • the wall & become entrained within the boundary layer • Initial attachment is based on electrostatic attraction & physical force • -Some of the reversibly adsorbed cells become irreversibly adsorbed. • Stabilized chlorine/ bromide ion works in stage 2 • ☞ No adhesion or removal of pioneer bacteria by killing • planktonic microorganism or hindering bacteria attachment

  10. 3) Slime formation • Adsorbed bacteria excrete extracellular substance • These polymeric substance, or glycocalyx, consists of charged • & neutral polysaccharides groups • These substance facilitate attachment & act as an ion-exchange • system for trapping & concentrating trace nutrients • In a mature biofilm, more of the volume is occupied by the loosely • organized glycocalyx matrix (75~95%) than by bacteria cells (5~25%) 4) Secondary colonizers • As well as trapping nutrient molecules, the glycocalyx net also snares other types of microbial cells • through physical restraint and electrostatic interaction • These secondary colonizers metabolize waste from the primary colonizer as well as produce • their own waste which other cell then use in turn

  11. 5) Fully functioning biofilm • The mature, fully functioning biofilm is like a living tissue on the wall surface • Mature biofim are imaginatively described in the article “Slime City” • As stabilized chlorine & bromide ion has outstanding penetration properties • it overcomes the protective barrier of the aged bio-film and then disintegrate. HOBr by reaction of stabilized chlorine & bromide ion detach the slime structures in addition to the biocidal effect.

  12. (B-2) Penetration rate of chlorine-based biocides into biofilm • The mean penetration time into ~1mm thick biofilm P.S.Stewart et al. Center for Biofilm Engineering and Department of Chemical Engineering, Montana State University Journal of Applied Microbiology 2001,91,525-532

  13. (B-3) Increment of U (overall heat transfer coefficient for condenser) by biofilm ☞ Additional surface area required for compensating water side biofouling

  14. (B-4) Easier cleaning: reduce the cleaning effort - Cleaning works may be hazardous to health w/o the use of protective equipment (dispersed & inhaled germ aerosols, legionella, sick building syndrome, etc)

  15. (B-5) Fountain Application (EverlandYoungin Korea) ⇒ No odor ⇒ with Justeq 07 after 1 week w/o biocide

  16. (C-1)Mechanismof action of industrial biocide Biocide Electrophiles Membrane active Oxidant Electrophiles Lytic Protonophores Chlorine Bromine Ozone Peroxides Isothiazolones Aldehydes Carbamates DBNPA BNPD Quats Biguanides Phenols Alchols Week acids Parabens Pyrithiones Humidifier disinfectant: PHMG, PGH, CMIT/MIT, Technical brochure of PPChem The mechanism of action of Isothiazolone Biocides Terry M. Williams DBNPA: 2,2-dibromo-2-cyanoacetamide BNPD: 2-bromo-2-nitropropane-1,3-diol

  17. (C-2) Humidifier Disinfectants

  18. (C-3) Toxicities of MIT & CMIT Methylisothiazolinone, A Neurotoxic Biocide, Disrupts the Association of Src Family TyrosineKinases with Focal Adhesion Kinase in Developing Cortical Neurons MIT(methylisothiazolinone) and its closely related analog, chloromethylisothiazolineone or CMIT, affect the ability of young or developing neurons to grow processes (axons and dendrites) in tissue culture 2. The toxic actions of MIT on developing neurons occurs at much lower concentrations than those inducing lethal injury (1-3 micromolar).CMIT is even more potent, working at concentrations as low as 0.1 micromolar ☞ One micromolar is approximately 0.115 parts per million. • Journal of Pharmacology and Experimental Therapeuticsjpet.aspetjournals.org • Published online before print March 17, 2006, doi: 10.1124/jpet.106.103044 • JPET June 2006 vol. 317 no. 3 1320-1329 • Dr. Elias Aizenman, Department of Neurobiology, University of Pittsburgh • School of Medicine; E1456 BST, Pittsburgh, PA 15261. E-mail: redox@pitt.edu • 2. From Wikipedia, the free encyclopedia: Key word (methylisothiazolinone)

  19. (C-4) Physico-Chemical Properties of Sodium hypochlorite solution Melting Point: -6°C (21 deg F) (5% solution) Boiling Point: Decomposes above 40°C (104 deg F) pH value: Approx. 11 Odour chlorine (bleach) odour • Odour Threshold: Not applicable. Odour is due to breakdown products such as chlorine. • Stability: Sodium hypochlorite solution decomposes slowly. • Decomposition is speeded up by heat (temperatures above 40 deg C) and light. • Hazardous Decomposition Products: Chlorine, oxygen, sodium chlorate.

  20. Corrosion: Test results of Metal corrosion (40℃) ①②③④ ①②③④ ①②③④ ① de-ionized water ② stabilized chlorine/bromide ion:100 ppm ③ 12% NaOCl:60ppm ④ competitor:40ppm + NaOCl:60ppm interface Nail 1day Brass 3 days Sus 304 1 month Due to corrosive gas, corrosion occur above interface of ③ & ④

  21. Certification 1 : U.S.A - EPA Reg #: 84024-1 (Oct 18 2007) California EPA Reg (May 25, 2012) ※ Justeq 07: Brand name in U.S.A

  22. Certification 2 : Japan (Dec 22 2011) - ☞ Chromosomal aberration test ※ Ecocide 100: Brand name in Japan

  23. Certification 3 : Japan (Sept 3 2010) - 微生物を用いる變異原性試驗 (Ames 試驗) ※ Ecocide 100: Brand name in Japan

  24. Sub-registration in U.S.A

  25. Summery of Justeq 07 • Excellent biofilm penetration • Not be consumed by the EPS(exo polysaccharides) contained in the slime layer NaOCl(strong oxidizer) react and are consumed by EPS • Penetrate to kill the bacteria within the slime layer, leading to removal of existing slime deposits • Easy installation of supply systems (Pump & tank) • Protect the operating personnel - No damage by Justeq 07 (no chemical burning & skin irritation)

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