Published by Chris Williams, Operational Scientist at United Utilities
I am looking for any anecdotal experiences of dosing chlorine dioxide into a floc-sed process.
Any problems encountered etc. ?
I would want to know why you need to dose chlorine dioxide prior to providing an answer. What is the process involved and why do you want to dose chlorine dioxide in particular?
Published by Don Sharpe
Chris, you may also want to consider using ozone as an alternative. We are installing our ozone dosing systems on various streams including cooling towers and wastewater applications as well. It is inexpensive compared other oxidizing agents and is environmentally friendly. Please contact me at jeffp@filtroglobal.com and I will send you details.
Published by Jeff Pollard
No re ozone. It is a good oxidizer and disinfectant but adding it to untreated water will produce large amounts of bioavailable DOC and AOC that will also produce more DBPs when you add the disinfectant for distribution. That will also provide greater opportunity for problems during distribution from microbial activity. It does not sterilize the water.
Published by Joseph Cotruvo, President at Joseph Cotruvo & Associates, Water , Environment and Public Health
Nothing detrimental to floc-sed process by dosing chlorine DI oxide as far our experience.
Published by Shirish Kardile, Consulting Engineer at K Consultation
Hi Chris,
The major problem you will encounter is when you do not know the threshold quantity of the Chlorine Dioxide you are to dose to achieve your desired disinfection. You can underdose or overdose which in turn, causes other problematic reactions. I suggest you do a microbiological analysis of the sample and determine required quantity/dosage. You can as well use, Sodium Hypochlorite in the right determined quantity.
Regards
Justin
I was responsible for dosing ClO2 as a pre-oxidant during pilot operations about a decade ago, upstream of alum flocculation. I don't recall any particular problems with that part of the pilot. I'm happy to discuss further, or you might be able to find the project report. This was the project: https://www.iwapublishing.com/books/9781843398097/advanced-water-treatment-estuarine-water-supplies
Published by Jonathan Musser, Process Engineer at Associated Engineering
Why add during floc-sed. Are you disinfecting or modifying the chemistry? That will consume more of the chemical. Maybe better to add after filtration if you are using it for disinfection. Chlorine dioxide decomposes to chlorite and chlorate. Be careful not to exceed the WHO Guidelines.
Published by Joseph Cotruvo, President at Joseph Cotruvo & Associates, Water , Environment and Public Health
use ECP, extra stabilised hydrogen peroxide. much safer, much cheaper, longer lasting, easy to dose, easy to measure. www.bieau.be
Published by Gino Quackels, Owner
Agree with Joseph's comments that higher dose of ClO2 would be needed during floc-sed and furthermore, ClO2 may react with floced materials and generate undesirable by-products.
Published by Ali Safarzadeh Amiri, Consultant
Thanks but we already have the process installed. Seems to be working ok but just interested in chatting to people with first hand experience of using it longer term.
Published by Chris Williams, Operational Scientist at United Utilities