Disinfection - controlling chlorine dioxide residual

Hi,

I am struggling to control chlorine dioxide residual within 0.3ppm to 0.8ppm at a sea water treatment plant.

Does any one know how best i can automate the disinfection besides using an ORP signal?

Your help much appreciated!

Taxonomy

• Chlorine Dioxide
• Chlorination
• Sea Water Filtration
• Sea Water Desalinisation
• Chlorine Dioxide Treatment
• Disinfection

6 Answers

1. The probe may provide for analyses ClO2 with feedback system and automatic dosing system also available the water flow for probe should be constant. Oxidation-reduction potential, or ORP, is a measurement that indicates the degree to which a substance is capable of oxidizing or reducing another substance. “ORP is a measure of the cleanliness of the water & its ability to break down contaminants”. It has a range of –2,000 to + 2,000 and units are in “mV” (millivolts).ORP results help predict the oxidation state of ions in solution and whether certain reactions may take place. Generally, tap water has an ORP from +200 to +600mv. Bottled water tends to have high ORP levels of more than +400mv.A positive ORP reading indicates that a substance is an oxidizing agent.  The higher the reading, the more oxidizing it is. Chlorine is a very strong oxidant that kills many micro-organisms ClO2 is 2.6 times more effective than chlorine. Chlorine and chlorine dioxide are both oxidising agents (electron receivers). Zobell’s solution  is the most popular reference standard for ORP. Zobell’s is the easiest to find commercially and is more stable over time than Light’s solution

2. Well one of the approach is as Nikola has stated here. Besides this if you want complete automation the other option besides ORP is to use online chlorine dioxide meters that are available from Hach and probably Hanna

3. Envirolyte machines produce Hypochlorous Acid (called Anolyte ANK), which is Safe, Cost Effective and has far less by-products than other Chlorine based products. It is far more effective than Sodium Hypochlorite and will remove Biofilm and any Scale build-up. ORP or Free Available Chlorine Controller and probe will provide stable control. View www.envirolyte.co.uk

4. I agree with Prof Nikola which be quite complicate but this way will be good for you if you still want to use ClO2 but I agree with Prof Joseph too in the other hand you can use Hypochlorite is easier and cheaper especially  in term of safety.

5. ProMinent has ClO2 selective probes and you can set PID regulation of dosing pump via simple controller, but water flow rate must be relative constant.

   1 Comment

   1. I am into chlorine dioxide disinfection in India. I have regular requirements for testing of residual chlorine dioxide in the water. Could you please send me details of the same to advenvtech@gmail.com. 

      You could probably direct someone at your India operations to send me the details.

      1 Comment reply

      1. I am not working for ProMinent, but I have Fw: your message to their representative in Serbia. I am working in www.mwt.rs Regards, Nikola

6. Chlorine dioxide dosing and residuals can be tricky. You also should be concerned about chlorite and chlorate residues. Chlorine or hypochlorite is easier and cheaper. THMs are a questionable concern.