Ozone (O3) sewage treatment technology was applied to water treatment in 1905. With the progress of related technologies and the reduction of the cost of ozonization, it is generally considered to be a promising water treatment method. Because of its technical and economic advantages, it has been widely used, and some research and engineering application results have been achieved. The following Xiaobian of Qingdao Aikang ozone generator manufacturer introduces the principle of ozone in the process of sewage treatment, deodorization, decolorization and COD reduction.
1. Reduction of residual sludge by ozone
Activated sludge process can improve the daily sewage treatment capacity, and as a common sewage treatment technology has been widely used at home and abroad, but the residual sludge generated in the sewage treatment process has become a problem, and the sludge treatment cost accounts for a large proportion of the entire sewage treatment cost. Among the reduction technologies of residual sludge, the reduction technology of pre-treatment of sludge with ozone has been relatively mature.
The ozone-treated sludge enters the aeration tank together with the target wastewater as a part of the sewage, and is used by microorganisms for digestion and partial conversion into carbon dioxide. After such a pretreatment process of ozone to the sludge, the remaining sludge is greatly reduced. Ozone residual sludge reduction technology site needs ozone generators, energy consumption is large, the development of high-efficiency ozone generators and ozone utilization has a great role in reducing the cost of sewage.
2, ozone on water deodorization
The substances that produce odors in the wastewater treatment process are mainly composed of carbon, nitrogen and sulfur elements.
Only a few odor-producing substances are inorganic compounds, such as ammonia, phosphorus, and hydrogen sulfide; Most odor-producing substances are organic compounds such as low molecular weight fatty acids, amines, aldehydes, ketones, ethers, etc. According to the influent analysis of my sewage treatment plant, 80% of the influent is domestic sewage, that is, the content of organic matter is very high, and the content of inorganic compounds is relatively small.
Odor producing substances are mainly organic compounds, such as low molecular weight fatty acids, amines, aldehydes, ketones, ethers, etc. These substances have active groups, which are prone to chemical reactions and are particularly prone to oxidation. Ozone has the characteristics of strong oxidation, oxidation of active groups, odor disappearance, so as to achieve the principle of deodorization.
In addition to removing odors, ozone can also prevent the recurrence of odors. This is because the gas produced by the ozone generator contains a lot of oxygen or air, and odor-producing substances are easy to produce odors in an anoxic environment. Ozone treatment can prevent odor regeneration by forming an oxygen-rich environment while oxidizing and deodorizing. In order to improve the sewage treatment environment of urban domestic sewage plant, the effect is relatively large.
3. Ozone decolorization of water bodies
With the attention to the environment of tap water source and the reuse of secondary treatment sewer, the decolorization of secondary treatment water has been paid more and more attention.
As for the color and taste caused by humus, the average color of the water is 10 degrees. The maximum is 20 degrees. This chroma does not meet the water quality standards that are completely removed by the general condensation precipitation and sand filtration process, and may even exceed the worst standards. After ozone treatment, the color can be reduced to less than 1 degree. Usually, the reason for the coloring of tap water is the high content of iron and manganese. If these metals are in a free state, they can be completely removed by conventional methods. If the raw water contains humus and sometimes forms chromium salts, it is very difficult to treat by conventional treatment. Therefore, decolorization is also an important factor in ozone treatment.
4, the principle of ozone action
The decolorization mechanism of ozone: With the vigorous development of molecular biology, microecology extends ecology to the molecular level.
In fact, both protein and nucleic acid molecules are organic, they are composed of carbon, hydrogen, oxygen, nitrogen and phosphorus or sulfur (C, N, O, N, P or S), and the toxic shell is composed of many protein subunits, namely shell particles. Each shell particle is linked by non-covalent bonds and symmetrically wound together, proteins consist of multiple chains, and nucleic acids consist of chains of nucleotides.
