What are the common treatment processes for water with a high COD level of over 10,000?

First, you need to consider the biodegradability of your water, that is, what the BOD5 value is； With such high COD levels, an anaerobic process is generally used first, followed by an A/O process. If the standards are not still met, chemical treatment methods such as coagulation or NaClO oxidation can be considered.

First, it is necessary to consider the biodegradability of your water. With such high COD levels, treatment methods such as an anaerobic-aerobic biological combination process, high-efficiency air flotation-pure oxygen biological treatment, or a two-stage A/O process are generally used. If the standards are still not met, chemical treatment methods can be considered, such as coagulation or oxidation with NaClO.

Based on the properties of the main organic pollutants in the wastewater, physicochemical pretreatment is used to reduce COD, while chemical oxidation is employed to reduce toxicity and increase the B/C ratio; subsequently, appropriate biochemical treatment is applied.

Generally, for a COD level as high as yours, physical-chemical treatment must be carried out first, followed by biological treatment. Physical-chemical treatment typically involves coagulation, the addition of acids or bases, as well as oxidation or advanced oxidation methods to improve the biodegradability of the substance, after which biological treatment takes place. There are several different methods for biological treatment, and the choice depends on the nature of the pollutants present.

At such high concentrations of organic matter, biochemical treatment alone is not sufficient to achieve a COD level of less than 150; pre-treatment is necessary, such as coagulation using PAC+PAM and sedimentation, or methods like Fenton oxidation or photocatalytic oxidation. Membrane separation techniques can also be employed

It depends on the organic substances that produce COD; if they are aromatic compounds, resin adsorption can be considered. gfmin@sina.com

First, it is necessary to examine the components of pollutants in the wastewater; if the salt content is high, multi-effect evaporation is the best option. Other methods are difficult to be effective.

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I know of a factory whose COD level was over 20,000; by using three-effect evaporation along with chemical treatment, it was reduced to around 100

It is possible to consider using anaerobic lagoons for treatment, followed by measures such as SBR and aerobic lagoons

Is it high occasionally or always? If it’s occasional, it can be placed in the accident treatment tank first and then dealt with gradually.

What patent? Where can I find it? ~~~~~~~~

The current process is water intake – air flotation – aerobic/anaerobic treatment – air flotation, and it does not meet the requirements: L

LZ only mentioned the COD of wastewater and wanted to know what treatment processes could be used; what everyone discussed was like using a cannon to kill mosquitoes – mere talk without any practical value. In fact, it is necessary to discuss the specific water quality indicators, what type of wastewater it is, and the volume of water, so that a discussion can take place. If the water volume is low, a incinerator might be more suitable. The water volume is high, but its biodegradability is poor; is the biochemical method suitable? Of course not. Which method should be chosen? Physical coagulation, electrochemistry, strong oxidizing agents – these methods can all be used for pretreatment. It’s not possible to determine immediately which one is the most appropriate. It refers to good biodegradability; anaerobic and aerobic methods are used, with various types of anaerobic and aerobic approaches available. Determining the most suitable combination of processes depends on factors such as water quality, water volume, the characteristics of the water, and the local environment.

The electrolytic method can be used to reduce COD

First, the biodegradability can be improved based on the water quality; next, the COD value needs to be reduced; and finally, the standards must be met.

The air flotation + A/O + air flotation process used in our factory works very well!