Please tell me what are the reasons why the treatment effect of biochemical water drops significantly when the temperature is below 10 degrees Celsius? How should it be solved?
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In Guangdong, the weather around the Spring Festival was bad. The temperature dropped significantly compared with previous years and lasted for a long time. The sewage pool was not equipped with heating equipment, resulting in poor biochemical treatment effects. The volatile phenols and COD in the biochemical effluent were much higher than usual. Please discuss it: Will the treatment effect decrease significantly if the biochemical water temperature is below 10 degrees Celsius? What's the reason? What should we do if we cannot add heating equipment? This post was last edited by Tan Zhaofeng on 2008-2-16 13:54 ]
It should go down. Because the activity of microorganisms generally needs to be above 15 degrees Celsius to remain normal.
yes! The activity of microorganisms is generally best between 15°C and 40°C. Beyond this temperature range, the activity decreases and the processing capacity is low.
We have now adopted the method of increasing the return flow and reducing the load. The effect is there, but the processing capacity has been reduced by 30---50%. Are there any other more effective methods? This post was last edited by Tan Zhaofeng on 2008-2-15 22:09 ]
If the raw water temperature is above 30 degrees, insulation measures can be taken. In principle, if the temperature is 10 degrees lower, the activity of microorganisms will only decrease, and the suitable temperature should be above 35 degrees. The temperature can be increased through indirect heating, such as temporarily adding hot water for soaking coils or steam heating and other temporary measures.
Temporary heating facilities or reducing the amount of remaining sludge discharge can be partially alleviated.
Haha, thank you all for your help. Because in the Pearl River Delta region of Guangdong, most of the year-round temperatures are above 20 degrees Celsius, and only slightly lower in winter, which is around 15 degrees Celsius. It seems that there is no need to add heating equipment, and it is not very practical due to the conditions. I have also mentioned that we have increased the return flow and reduced the discharge of remaining sludge, but the effect is still limited. I would like to know if there are other better methods.
Increase biomass. Add some filler if you can.
Go back to 8th floor: Reducing the discharge of excess sludge actually increases biomass, or to increase biomass, you can only start by increasing biological sludge. To add filler, activated carbon powder is usually added to the biochemical tank to increase the adsorption capacity of activated sludge. This post was last edited by Tan Zhaofeng on 2008-2-19 13:14 ]
To reduce sludge discharge, the SVI of the sludge must be considered. There is an upper limit to the sludge concentration. When adding activated carbon, no matter how much you add, it will still be lost. If the landlord's problem persists every year, it is recommended to modify it.
Going back to the 10th floor, reducing the amount of sludge discharge does not mean no discharge, but it means appropriately increasing the amount of return sludge on a normal basis. Generally, the winter temperature here is above 10 degrees, and the cold time is not much, only half a month at most. This year is a bit special. In addition, under normal production, the temperature of the sewage is above 25°C. Two or three times a year, the quality of the sewage deteriorates due to the shutdown or maintenance of some devices, exceeding the range of biochemical treatment. We can only use biochemical treatment intermittently, so the biochemical water temperature will become lower due to the low ambient temperature, thus affecting the biochemical treatment effect.
You can start from around the treatment station to see if there is hot water, such as circulating water return water and other available water. You can increase the water temperature appropriately, and take measures such as reducing the discharge volume to stabilize the treatment effect.
Aeration tanks can be sealed with plastic sheeting
Laying a circulating water return heating line and turning it on in winter and off in summer should be effective.
The investment is too big, and it may only be used for a day or two, making it impractical. Generally speaking, there is no other good way but to reduce water inflow and sludge discharge. This is the only way.
Thank you for everyone's help. Now that the temperature has risen, biochemistry has returned to normal. On the premise of ensuring the quality of the effluent, the treatment capacity is gradually increasing.