1. What is chlorine dioxide?
Chlorine dioxide disinfectant is a green, safe, efficient and broad-spectrum disinfectant that can kill all microorganisms in aquaculture water, including bacterial propagules, bacterial spores, fungi, mycobacteria and various viruses. It has strong adsorption and penetration ability to the microbial cell wall, can effectively oxidize the thiol-containing enzyme in the cell, and can quickly inhibit the synthesis of microbial protein to destroy the microorganism. However, chlorine dioxide has a very weak destructive effect on eukaryotic cells. Fish is a vertebrate, which is a structure of eukaryotic cells, and its enzyme system cannot enter, so chlorine dioxide has little harm to animals such as fish. At present, it is believed that chlorine dioxide is mainly harmful because some manufacturers have added trichloro and dichloroisocyanuric acid to dispose of chlorine dioxide. It is a recognized environmentally friendly green disinfectant. It is also the most cost-effective disinfectant for aquatic products at present, and a large number of high-quality aquaculture users have the experience of using chlorine dioxide.
2. Mechanism of chlorination of chlorine dioxide?
The chemical formula of chlorine dioxide is ClO2, and its sterilization mechanism has the following three types:
1) Reacts with amino acid cysteine, tryptophan, and tyrosine, but does not react with viral ribonucleic acid (RNA).
2) Change the synthesis of viral capsid proteins and lipids.
3) Increase the permeability to the outer membrane of the bacteria/virus.
The main advantage of using chlorine dioxide for disinfection is that it is independent of the pH of the reaction. Unlike chlorine, chlorine dioxide deactivates disease-causing microorganisms at the same rate between pH 5-9. Therefore, chlorine dioxide has a stable sterilization efficiency in the range of pH 6.5-9 in the pond, which is an advantage that other disinfectants cannot match.
3. What is the use of chlorine dioxide in aquaculture?
Chlorine dioxide is a strong oxidant and an excellent disinfectant. It has many uses in pond culture, mainly in:
1) Regulating water quality: In the process of breeding, concentrated water, excessive organic matter, ammonia nitrogen, sub-salt and hydrogen sulfide are often exceeded. The use of chlorine dioxide can solve these problems well. Chlorine dioxide water and ammonia, sulfides and organic matter. The reaction acts to decontaminate, remove cockroaches, deodorize, degrade toxins (heavy metals, arsenic, sulfides, phenols, ammonia), flocculation and sedimentation, etc., and to remove water odor.
2) Chlorine dioxide disinfectant is mainly for the prevention and treatment of bacterial diseases, mainly including: bacterial sepsis, red skin, rotten sputum, rotten tail, enteritis, white skin, printing, vertical scales, hemorrhoids and other common diseases. In actual use, due to the limited technical level of the farmers, the use of chlorine dioxide in the whole pool after the occurrence of disease can often achieve better results. The reason is that 70% of the common diseases in aquaculture are Bacterial diseases, therefore, chlorine dioxide can also be used for disease prevention under stress conditions such as weather changes and pulling nets during aquaculture.
3) Algae killing: When the water is dark green, cyanobacteria bursts, abnormal water color, etc., the use of chlorine dioxide can quickly destroy the chlorophyll of algae, kill algae, and play the role of clean water and refreshing water. The side effects are very small, and the safety factor of common algicidal drugs such as copper sulfate and erythromycin is more than 10 times higher.
4. What are the advantages of chlorine dioxide compared to bleaching powder and strong chlorine?
Chlorine dioxide is the fourth generation of high-efficiency disinfectant. Compared with chlorine preparation (bleaching powder, strong chlorine essence), sterilization and disinfection with chlorine dioxide have the following advantages:
1) Broad spectrum, high efficiency, killing bacteria, viruses, fungi, algae and even protozoa. The oxidizing power of chlorine dioxide is 26 times that of chlorine (that is, the chlorine content of chlorine is 100% under the same weight, and the effective chlorine content of chlorine dioxide is 263%), which is sodium hypochlorite (hypochlorous acid is bleaching powder and strong chlorine). 3-4 times the effective effective ingredient).
2) The dosage is small, non-toxic, safe and convenient to use. Chlorine dioxide does not have any adverse effects on cells of higher animals. Tablets can be directly spilled into water for convenient and safe use. And often used, pathogenic microorganisms do not develop resistance to it.
3) The bactericidal effect is not affected by pH (in the range of 6-10), ammonia nitrogen and organic matter. Bleaching powder, strong chlorine, etc. have better effect under acidic water conditions. Then, when the pH is above 6, the bactericidal effect decreases with the increase of pH. When pH=7, the bactericidal effect is only 50%, so when the chlorine preparation is used The dosage is large and the damage is great. Chlorine dioxide has the same bactericidal effect in the range of pH 6.5-9.0 in pond water, which greatly reduces the amount of use and reduces the harmful effects on fish. Similarly, chlorine preparations react under ammonia nitrogen and organic conditions to form chloramines and organic amines, which reduce their bactericidal efficacy, while chlorine dioxide does not produce these toxic and harmful substances.
4) Deodorization and decolorization. When the mass fraction is 1 mg/L, the removal rate of hydrogen sulfide by chlorine dioxide is 84.3%, and the removal rate of hydrogen chloride by hydrogen chloride is only 35.9%. Therefore, chlorine dioxide has a stronger function in the treatment of black hair odor in water.
5) It has the function of iron and manganese in oxidized sediment. It has an excellent improvement in the black odor of the bottom mud, while the chlorine preparation does not.
5. What are the advantages and disadvantages of chlorine dioxide tablets and powders?
The advantages and disadvantages of powders and tablets are:
1) The use cost of the powder is low, and the cost of using the tablet is relatively higher than that of the powder;
2) When the powder is used, it needs to be activated. When the activation occurs, the loss rate is large due to the overflow of a large amount of gas, and the operator can easily inhale a high concentration of chlorine dioxide to affect the health; the tablet is convenient to use and is directly thrown into the pond;
3) After the powder is activated, it is mainly disinfected against the water layer, and the therapeutic effect on the upper layer fish disease is better; after the tablet sinks into the bottom of the water, a large amount of chlorine dioxide is generated at the bottom of the water, mainly for bottom disinfection and bottoming. In view of the safety to users, tablets in aquaculture, especially effervescent tablets, are the development trend of chlorine dioxide. It is the best embodiment of the comprehensive technology of the manufacturer to produce chlorine dioxide tablets with low price, fast dissolution rate and high conversion rate of chlorine dioxide.
6. How to evaluate the quality of chlorine dioxide?
1) Look at the packaging, the regular chlorine dioxide manufacturer, the packaging is divided into inner packaging and outer packaging, the inner packaging is anti-corrosion bag, mainly to prevent corrosion of the outer packaging, the outer packaging is moisture-proof bag, mainly to prevent chlorine dioxide from getting wet. The moisture-proof bag is an aluminum-plated bag. If the ordinary packaging bag is easily corroded, the moisture absorption of chlorine dioxide in a wet state may cause fire or explosion. Therefore, when choosing a chlorine dioxide product, first select the chlorine dioxide packaged in an aluminum foil bag.
2) Look at the color of the dissolved water: chlorine dioxide is yellow-green in the aqueous solution, generally take 250ml of tap water, add 1g chlorine dioxide powder or chlorine dioxide tablets, the water is yellow-green, the darker the color, the chlorine dioxide is proved The greater the concentration. Of course, if both varieties are dark yellow, it is best to determine the chlorine dioxide content directly from the readings by using the chlorine dioxide rapid analyzer to determine the chlorine dioxide content.
3) Look at the residue after dissolution: Individual immature enterprises, after the dissolution of chlorine dioxide in the tablet, there are many impurities left on the water surface and the bottom of the water. These impurities are caused by improper selection of binders and fillers. The formula is not mature, and most of it comes from small workshops. The quality and safety of using such products is difficult to guarantee.
4) Calculate the price/performance ratio of chlorine dioxide: that is, the money required to purchase a unit weight of pure chlorine dioxide. In plain language, it is the money that the farmer needs to buy 1 gram of real chlorine dioxide. Since the value calculated from the quantity of 1g is too small, the money spent by the farmer to purchase 10g of chlorine dioxide is used to calculate the cost performance of chlorine dioxide from different manufacturers.
