How Primary Clarifiers Work

hi John here in this video we're going to look at a primary clarifier specifically we're going to have a look at a circular primary clarifier I'm going to explain to you how it works we'll look at all of the main components and then we'll look at some of the factors that might affect clarifier performance clarifiers are used in a water treatment process known as sedimentation separating solids from a liquid using using only gravity can be done in a sedimentation Basin or a settling tank however if we use mechanical means to assist the separation of solids from liquid then we refer to the associated machine as a clarifier so let's now have a look at how the whole thing works we can see now we've got our circular primary clarifier it's called a primary clarifier because it's the first initial stage of treatment we refer to this as primary treatment or a primary clarifier and after this stage the liquid being handled will go for secondary treatment most likely in a secondary clarifier going to see these items installed in sewage treatment plants water treatment plants Pulp and Paper plants mining facilities and anywhere else where there's a large amount of water that needs to be treated prior to being discharged into the environment or being recirculated and reused again I'm going to now pause the animation and we're going to look at how it works so let's go all the way down to the bottom we can see here we've got an influent the influent is where the liquid the fluid will enter into the primary clarifier so we can think of this as being our Inlet or intake notice it's in the center of the primary clarifier sometimes it will be around the periphery or it will enter from the outside circumference of the clarifier just see if we can get in through the center see we're coming up now and as we come up do a little spin you can see we are now inside the primary clarifier what's going to happen now is we're going to pass through through these channels these ports and we're now inside the main body of the clarifier the main section where the water would enter we've got here a baffle plate this is actually referred to as an energy dissipating Inlet I'm going to zoom out so we can get a higher view because I think it's a lot easier to see what's happening so here you can see we came in through the port here we entered into the clarifier and we hit this wall here this baffle which is called an energy dissipating Inlet notice that some of the liquid would flow out this way and some of it would flow downwards the idea with the EDI is simply that we want to slow the velocity of the liquid down because if we can slow the velocity of the liquid down it's going to settle out a lot quicker and this means we're going to be able to separate these suspended solids from the liquid so essentially if we can slow down the velocity and let gravity do its work then we're going to be able to separate the solids from the liquid a lot faster and this means we can have a higher flow rate through the clarifier which means we're getting more use of the clarifier for our money so it's increased efficiency and increased capacity so let's have a look now at what happens after that we can see we've got another baffle plate here again this is to slow the velocity of the influent down once the velocity has been slowed down we can split the clarifier into three zones got here our Inlet Zone we've got our settling Zone which is if I go to the side here roughly going to be from where our Inlet Zone ends to the outer wall which is our Outlet Zone the settling zone is where the solids will gradually separate from the liquid due to the force of gravity and also because we slowed down the velocity so that's how a primary clarifier works if you like this video please do share or like it on social media it really does help us out and allows me to produce more and more content and if you'd like to see many more engineering related tutorials then go to the video description area and there you'll see a number of links to our online video courses and if you click on those links you'll be able to purchase them for a discount price thanks very much for your time

Channel: saVRee

Views: 134,004

Keywords: how primary clarifier works, primary clarifier wastewater treatment, primary clarifier, wastewater treatment process, primary clarifier parts, primary clarifier design, primary clarifier operation, primary clarifier - 3d technical animation, wastewater treatment, wastewater treatment plant, wastewater treatment plant design, wastewater treatment plant tour, primary clarifier process, clarifier, circular clarifier, circular primary clarifier, clarifier water treatment

Id: bBS2UcYaSOM

Length: 5min 13sec (313 seconds)

Published: Tue Sep 25 2018