Passing sludge through vertical precipitator

[BTJCM]

Hello, I have a problem with passing sludge through vertical precipitator. The formed sludge due to the coagulant used is beginning to rise from the transfer of waste water to precipitator(and that's not ok). I can't use filter press for the sludge. I think I need to use some kind of filters, but there is problem with that, because a membrane(skin) is formed on the surface of the precipitators, so they will block the holes(where the waste water goes to sewage) very quickly. I'm searching for opinions and solutions.

 

[ashtree]

Can you provide a schematic or a sketch of your equipment layout and provide some details on the sludge you are treating and the coagulant in use?

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[BTJCM]

Hi ashtree, we tested CFS which I described in my last theme " How to dose coagulant ", and we will make a test with the polyaluminum oxychloride. The formed sludge due to the coagulant used is beginning to rise from the transfer of waste water to precipitator through perforated tubes. We do not treat sludge, just store it in a shaft and when the shaft it's full we call a certified company to ship it(wastewater with sludge). The flow rate through perforated tube is approximately 80 l/min, but that's is not the exact value because membrane(skin) is formed on the surface of the precipitators and they block the holes. Membrane(skin) is formed from surfactants which are you used in production area. If it will be more clear to you I can make a pictures and describe the working process in our vertical precipitators. Feel free to ask, I will try to give you the best answer I could.

Best regards

 

[springrise]

Hi, I guess you are talking about vertical sedimentation tank where you bring the sludge-water mixture to the bottom (by perforated tubes) and the clean water is supposed to overflow at the top (through an overflow weir maybe?). Sludge is supposed to stay at the bottom and it's drawn off in certain time intervals.
Can you confirm if this is correct?

The problem of solids passing the sedimentation can result from your coagulation/precipitation process (too small flocs) or from the design of your sedimentation tank (design versus loading), or from both.
What is the geometry of your tank?
Do you have some design documentation saying what mass loading (kg solids PER cross section area PER time) is it supposed to handle?
Do you operate in continuous mode? Any chances to operate in batch mode?

 

[BTJCM]

Hi springrise, I will explain the entire process. The waste water first goes to tank(1), after that is going to mediators(2), where the waste water is aerated, because of the high pH the waste water is passing process of neutralization, where carbon dioxide(4) is dosed according to the indication of electrode(7). Dosing of coagulant(5) it's happening before mixer(6). After the mixing process of the waste water, they go in cylinders(10), where on the bottom of cylinders are installed reflectors(11), in the corresponding vertical precipitators(9). In the upper part of the precipitators are situated the perforated tubes through the waste water goes to municipal sewerage.

https://files.engineering.com/getfi...db4e-4d9b-b82c-0a3019881fc9&file=SchemePC.jpg

Best Regards,
George

 

[springrise]

can't open the attachment.. can you please try again? maybe change the name of the picture file.

 

[BTJCM]

Hi springrise, thank you for you feedback there was some issue with the name of the file. I posted a link because for some reason even If I change the name doesn't work properly, but from the link it's working fine.

Best Regards,
George

 

[springrise]

thank you,
what are the dimensions of the precipitators - diameter and height?

 

[BTJCM]

Hi springrise, diameter = 2.25 m, height = 4 m.

Best Regards,
George