Activated carbon decolorization issue
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One of the treatment methods involves using activated carbon for decolorization. Previously, a small amount of activated carbon was sufficient to achieve good decolorization results; however, recently the effect has been poor. So I increased the amount of activated carbon used, but the color of the water became even darker. Before adding it, the water was light red, but after adding the activated carbon, the color didn’t fade and instead turned an even darker red. I wonder if the activated carbon is fake? Or are there other reasons? Please give me some advice!
It may be related to the decolorizing ability of activated carbon, as well as the pH level of the water.
The key is to check whether there has been any change in the type of activated carbon, or whether there have been any changes in the conditions of your materials, especially regarding the parameters of the output product; the root cause needs to be identified in this way. Additionally, for liquid decolorization, ion exchange resins can now be used as a substitute; you might want to give it a try. For relevant information, please check the in-site messages. Thank you!
1. Has there been any change in the material composition?； 2. Is there any change in the pH value during decolorization? ； 3. Decolorization temperature ； 4. Has there been any change in the activated carbon? Basically, make judgments based on the points mentioned above; please refer to them.
This post was last edited by CoCo070563 on 2016-4-29 at 23:20. A decolorizing agent can be used. Our company is engaged in the production and sales of water treatment chemicals (such as polyaluminum chloride, polyacrylamide, sodium sulfide, ferrous sulfate, heavy metal scavengers, defoamers, decolorizing agents, and a range of other large-scale chemical products). Those who have relevant business interests or resources are welcome to cooperate with us for mutual benefit and shared profits! ! ! Contact person: Manager Qin QQ: 961748201.
Activated carbon has an excellent decolorization effect. If this effect declines, there could be several reasons: 1. There may be issues with the quality of the activated carbon; a decrease in its iodine adsorption capacity leads to a reduced adsorption efficiency. To determine whether there are such problems, tests or comparative experiments can be conducted； 2. An increase in the color intensity of the raw water or the concentration of organic substances results in insufficient adsorption capacity by activated carbon ； 3. Changes in operating conditions generally have a direct impact on the adsorption efficiency of activated carbon; the lower the pH value, the better the adsorption effect ； 4. Water temperature changes: lower water temperatures are more conducive to adsorption, while higher water temperatures are more conducive to desorption ； 5. Changes in hydraulic conditions: the greater the contact between activated carbon and water, the more favorable it is for adsorption ； 6. Variation in contact time: The contact time between activated carbon and water should generally be maintained at 20 minutes or more; too short a time will reduce the adsorption efficiency ； 7. The separation time varies; when the stirring intensity is high and the carbohydrate separation time is short, the decolorization effect is reduced.
You can first carry out flocculation treatment before using activated carbon adsorption; this will reduce your processing load significantly
It is not possible to judge based solely on color, as whether the ultra-fine activated carbon in the wastewater has been completely separated after decolorization directly affects the color assessment. The COD level of the effluent can be measured to determine the change in COD before and after adsorption. Additionally, the organic substances in your wastewater may have deteriorated; prolonged exposure to air leads to oxidation reactions that result in color formation.