Chlorine dioxide has been used for many years as a means of purifying clean water (in the US since 1944). It has been approved and recommended by the US-EPA as an additive to replace chlorine for environmentally friendly drinking water purification. (For reference, click here)
Its oxidizing ability as a biocide, particularly at high pH, makes chlorine dioxide an ideal choice for clean water purification. Chlorine dioxide is used in pre-oxidation and post-oxidation to remove natural organic components (which react with chlorine to produce trihalometanes (THM), which is a carcinogenic substance). Chlorine dioxide also helps in removing inorganic molecules such as manganese and iron. Chlorine dioxide will react with iron and manganese at any pH by converting it into a hydroxy form which then settles.
In general, chlorine dioxide is more effective as a disinfectant than chlorine when processing pathogenic microbes such as viruses, bacteria, and protozoa. These include cysts from Giardia and oocysts from Cryptosporodia which can cause gastrointestinal infections.
501/5000Chlorine dioxide will also remove and control biofilms contained in the clean water distribution network. Chlorine dioxide can be used at very low concentrations. The amount of pre-oxidation will depend on the amount of contamination in the water, but is usually between 0.5-2.0 ppm. The post-oxidation concentration used was 0.2-0.5 ppm to achieve good disinfection results. Chlorine dioxide is active as a biocide for at least 48 hours, thus ensuring longer water cleanliness.
Some of the advantages of chlorine dioxide when used in clean water purification applications are:
- The main disinfectant
- Maintain taste and smell
- Reduces THM
- Reduces HAA
- Removes iron and manganese
- Maintain the nitrification process in the chloramine system
- It is safer than using chlorine gas
- effective over a wide pH range
- Does not react with ammonia-nitrogen
- Effective at low doses for contaminated systems compared to other biocides
- Very effective for controlling biofilms and algae
- Water tank; 100 ppm. Put it in the tank, leave it for 1 hour and then drain it.
- Clean water disinfection; 0.2-0.8 ppm.
- Circulating cooling water (continuous dosage); 0.1-1.0 ppm. Inject.
- Circulating cooling water (intermediate dosage); 0.1-5.0 ppm. Inject.
- Weekly maintenance of the pool: 1.2 ppm.
- Pool maintenance daily: 0.5 ppm.
- Fish pond; 0.01-0.5 ppm.
- Sanitize surface objects; 20 ppm. Soak or wipe for 5 minutes, let dry.
- Toilet sanitation; 200-500 ppm. Spray, wipe or rinse and let it sit for 20 minutes. Don’t pour it into the toilet hole.