APPLICATION OF CHLORINE DIOXIDE IN WATER STERILIZATION

New product of Nation-Lab

Chlorine dioxide generator NCD-5000

I. NCD-5000 system

The chlorine dioxide generator NCD-5000 manufactured by Nation-lab can directly produce chlorine dioxide (ClO2) in a concentration of about 5000 g / h by direct reaction between sodium chloride (NaClO2) and hydrochloric acid ( HCl). ClO2 products can be stored in tanks or cans to produce disinfectants, disinfectants ... or we can design a ClO2 dilution system according to customer requirements to treat swimming pool water, drinking water. or aquaculture ponds such as shrimp, fish ...

The NCD-5000 system was developed by NATION-LAB

II. Applicable fields

Drinking water: uses disinfection, oxidizes iron and manganese, removes odor and taste compounds, and prevents and eliminates bacteria.

Swimming pool water: used to disinfect, deodorize ...

Industry: use of sterilization process and disinfectant water products, bacteria prevention and elimination, biofilm control, coolant treatment ...

Wastewater: used for disinfection and odor control

Breeding: used to kill pathogenic bacteria, clean the pond, deodorize the barn ...

III. Characteristics of ClO2

Chlorine dioxide is a characteristic yellow, easily dissolved gas, oxidizing in water. The maximum concentration of ClO2 that can dissolve in water is 4000 ppm, which is the value at which it can reach equilibrium between the liquid and gas phases. Like ozone, the gas phase of ClO2 greater than 10% will cause an explosion, for this reason that ClO2 is often produced and used in place.

Chlorine dioxide is a very effective disinfectant and an oxidizing agent of organic compounds in addition to the ability to decompose odors, so it is widely used in many different fields with its effectiveness. It's great that products like chlorine don't have. When using the same concentration, ClO2 disinfects and decomposes organic compounds much more than chlorine (Cl2) and especially after using them, they do not form active ingredients such as trihalomethane, chloramine. In addition, ClO2 can oxidize unwanted odor and taste organic compounds in water such as phenols, algae and their decomposition products, after using the water with a pleasant odor and is less toxic.

Chlorine dioxide does not react with ammonium and ammonium compounds. This is an important difference when compared to chlorine form chloramines, which in turn can have a negative effect on the disinfection and taste of treated water. In contrast to chlorine, chlorine dioxide's effective bactericidal properties do not decrease with increasing pH. Chlorine dioxide has a very high stability in water. After oxidation, ClO2 is able to maintain its activity for a long time even at low levels, thereby effectively preventing the regeneration of algae and bacteria in water.

To create the ClO2 product, Nation-Lab performs a reaction (1) between sodium chloride and hydrochloric acid, to produce different concentrations of the product we mix and control the flow with a metering pump and a metering machine. concentration of ClO2 so ClO2 content emitted from NCD-5000 is adjusted and controlled according to will.

5 NaClO2 + 4 HCl --> ClO2 + 5 NaCl + 2 H2O               (1)

IV. ClO2 is used in water disinfection of shrimp farming in Binh Thuan C.P Company

Shrimp are cold-blooded animals, very susceptible to diseases, especially when the weather and environment change erratically.

They are active and eat more at night.

The growth of shrimp is associated with the ability of the individual to molt.

The living conditions of shrimp are at temperatures from 18 - 30 degrees C. When the temperature exceeds the tolerance limit, shrimp will suffer physiological disorders and die (with manifestations such as muscle curvature, muscle turbidity, shrimp inactivity, stop eating, increase breathing).

Depending on the development stage, the appropriate salinity for shrimp is different. Salinity affects alkalinity, pH, and growth of farmed shrimp. If the salinity exceeds the adaptive limit of the shrimp, it will cause shock reactions to the body, reducing their resistance to disease.

The suitable transparency for shrimp farming is about 30 - 40 cm

Suitable pH ranges from 7.5 to 8.5 and fluctuates during the day not more than 0.5. If the pH is too high or too low compared to the appropriate level, it will greatly affect the maintenance of the pH balance of the blood in the body, detrimental to the survival of the shrimp.

In shrimp ponds, alkalinity plays an important role in maintaining the ecosystem of the pond ecosystem - This is considered an important indicator of the effects of reducing pH fluctuations in water, limiting harmful effects. of the toxins available in water. The suitable alkalinity for shrimp is 80 - 120mg / l.

Dissolved gases: the content of oxygen, CO2, H2S at a stable level

=> Note: In order to ensure the living environment of shrimp seed, it is necessary to disinfect the water source to ensure that the larvae thrive and affect the quality of shrimp seed for later.

The reservoir is disinfected with ClO2

Test ClO2 content by lovibond machine with DPD reagent