DIY hybrid sediment settling chamber/vortex filter - "Muck Dropper"

[Catfishnut]

I am getting back to my bait tank/pond setup and filtration system design and I am curious of your evaluation and thoughts on my current aspect of this project.

I have deemed it necessary to incorporate a sediment trap/settling chamber to remove large debris before it reaches my bio-conversion stages for obvious reasons.
I haven't been too critical of this design thus far as I was really focusing in on other sections of the overall filter system. I have recently been researching the net for ideas and solutions to the pre-bio-converter-filtration unit and coming up with very little that enthuses me. Most everything is either overly expensive or would require continuous cleaning. High dollar Vortex units or multi-chamber settlement tanks which take up a lot of space or mechanical filter media that has to be repeatedly washed or replace are not the routes that I wish to follow.

Therefore, I have attempted to create a DIY "Muck Dropper" that would incorporate some advantages of a vortex and a multi-chamber settling tank and a mechanical filter all in one, but be simplistic, not as expensive and functional as well as very low maintenance overall. Please offer your constructive criticism of this design and bare with me as I attempt to describe it.

First item is the vessel itself, which I have available. It is a 55 gallon, open top (with a set-on cover lid) batch mixing tank with a 15° cone bottom. Inside this vessel, I was pondering installing a 1/2" thick round disc of polyehtylene at about 1/3 of the height from the bottom or 12" up. Directly below this disc, I would bring a 1" PVC pipe into the vessel with an angled fitting to direct the water from the pond into the lower portion of the chamber and guide it around the vessel's outer wall, akin to a vortex filter unit.

The pump to feed this will be a 350 gph magdrive PondMaster pump. It will have a prefilter unit attached to eliminate any sticks and large debris that might harm the pump impeller, but it will be able to take up the fish waste and leftover food items. Sticks and leaves and such I will manage more by keeping the pond (the tank) covered with a screen assembly, so I am not worried about this.

I started with a single 950 GPH magdrive pump for this project, but have reduced this to the 350 GPH pump for experimentation and cost savings and because I plan to utilize multiple pumps as a safety feature in case one fails. I should run approximately 950 GPH since the bait tank itself is max capacity of 970 gallons, but I will adjust for these discrepancies after I figure out the overall concept of the design.

Next item. I will have a two inch drain line exiting the bottom ot the cone (tank) with a knife gate valve or a 2" ball valve to expel the collected debris out into the yard.

Now, back to the 1/2" poly barrier plate. Since my 55 gallon vessel isn't the perfect dimensions for a vortex filter, I felt that I needed to enhance the function of dropping out the solids and the muck. Here is where the role of the plate comes in. I propose to drill numerous holes concentrated nearer the center of the plate (where the velocity of the vortex below should be the least) and insert many PVC pipes of either 1" or 1 1/4" diameter extending upwards to the upper water line in the vessel. I may leave the tops of these pipes open or I may cap the ends and cut slits/ drill holes in the sides of the pipes just below the caps, not sure what will work best, so I will just experiment with this when I get to that point.

The theory here is that, I already have a slight vortex action going on below the 1/2" poly barrier, but additive to that, the incoming water must lose much of it's velocity and energy in order to escape UP through these PVC pipes to the top of the vessel where it will be extracted. The loss of this kinetic energy should force the water to drop much of its sediment load below the poly barrier platform and with many, many, many pipes to channel the flow up to the top of the vessel, the water velocity through any one of them should be dramatically reduced, so hopefully even lightweight poop will drop out before it even makes an attempt to travel up the PVC tubes. Or at least it will have such a long residence time in the chamber below that it will break apart and saturate and precipitate out or become so fine that, if it does make it onward, it will pass through all other sections of the filter system without clogging them.

The nest component will be the extracting device which will simply be a 2" lakescreen with a fine mesh sock filter covering it to prevent any oops's from continuing on (mainly to prevent an accidental stick or hackberry seed from getting into the next pump.

The next pump will extract the mechanically filtered water from this sediment tank and push it on to the bio-converter, as clean as I can make it.

Can you envision my "Muck Dropper" sediment filter? It is difficult to describe in words what one see's in their mind sometimes, so I hope I got the idea across.

Please reply with your comments, I do need input on this.

Thanks

Catfish

 

[Mmathis]

OK, you lost me. Can you include a diagram?

 

[Catfishnut]

For some reason I am not able to attach or imbed any images.

Hmmpph!?

 

[Catfishnut]

Let me see if I can describe the main "guts" of this settling chamber better.

Start with a 55 gallon barrel and place a divider inside it so that the bottom 1/3 and the top 2/3 of the barrel are two separate chambers.
Drill 24 1" diameter holes in the divider and insert 1" PVC tubing into these holes. Make the PVC tubes about 18"-24" long.
Feed the dirty pond water into the bottom 1/3 section of the barrel through a 1" PVC inlet pipe at a 350 GPH rate.

In order for the water to escape the lower chamber and enter the upper chamber, it must go through the 24 1" PVC pipes.
Since the incoming water is moving at 350 GPH in a single 1" pipe, the same amount of water must exit through the 24 1" pipes.
Therefore the velocity of the water will slow down and the rate in each of the 24 1" pipes will be 1/24 x 350 GPH or 14.6 GPH.

Since the water has slowed down, it has lost energy and therefore, according to hydrodynamics, cannot carry the same load of sediments.
Per theory, the sediments should then drop out in the lower chamber where they may be expelled when necessary by opening the bottom drain valve for a brief time.
The clean(er) water should exit the top of the PVC pipes and can be pumped or gravity fed to the bio-converter.

The 24 1" PVC pipes are cut to 18"-24" in length and set vertically to add flow resistance as opposed to just having open holes in the divider.
This simply adds to the effect and makes use of the total space rather than just having open water for the top 2/3'rds of the tank.

The very bottom of this tank has a conical shape, like a vortex separator. Although It isn't very much (only 15° slope) I think it will provide some minor positive effect.
It should be better than just a flat bottom. The major difference here, compared to a vortex separator, is that the water has to exit upwards through the pipes near the
center of the barrel rather than overflowing into a pipe below the water's surface at the center of the vortex.

I could actually create multiple chambers, instead of just two. That would clean the water even moreso, but I don't have a good or simple plan to flush out the muck from the mid sections.
I will eventually have to clean the upper section out from time to time, but here I can install a removable plug in the divider and when the tank is mostly empty, just spray it out with the hose
letting the muck go down to the bottom level and out the drain.

Please keep in mind that I am trying to devise this settling unit in this way because I have the materials to do so, opposed to buying something else, even if that might be better.

Catfish

 

[Mmathis]

BTW, welcome back!

 

[Mmathis]

Are the 24 1" pipes elevated off the bottom of the lower 1/3? Trying to picture HOW the water will flow UP through those pipes, and and all I can picture is the pipes sitting on and in contact with the bottom ..... And I think I just figured out the answer to my next question . Duh!!

Sounds very interesting, and simple, too, like something I'd like to try, if it works. Mechanical filtration has been the biggest problem I've encountered so far, but anything like settling tanks/vortex chambers are too expensive and/or too massive to suit me. And my water isn't anywhere close to being as nasty as what you have to deal with. Have you built a prototype yet? And how will you get the bottom to have that conical shape?

 

[Catfishnut]

M,

The 24 1" pipes won't protrude through the "divider" between the upper and lower sections of the tank. I will actually install PVC fittings that will screw into the divider plate (after I drill the holes and thread them) and any portion of the fitting that does protrude will be ground off flush with the surface of the divider. Therefore, the bottom side of the divider plate will be basically smooth and flat. The pipes will "slip fit" into the other side of these fittings (one side of the fitting is threaded and the other is a slip fit). Also, the divider plate will be roughly 10-14 inches off the very bottom of the tank.

The tanks that I have and will be getting were manufactured with a conical bottom (intended so that all the contents could be drained and leave nothing behind). They are a specialty industrial type tank.

I haven't built a prototype yet. I have all the pieces (mostly) to put it together, but it will be a task to assemble, lots of drilling and cutting and threading. The tank part will be no problem, it is the divider plate that is going
to be a chore. I know that it will work, I just don't want to spend too much time and labor on it if I can find a better design or modify this one to make it work even better. I don't want to backtrack and start over.

I am in agreement with you regarding the expense and size of the store-bought vortex chambers. I looked into these and I really don't want to go that route, either! The concept is exactly what I need, but I'll be doggone if I'll pay $500 or more for one. Doing it this way, all I really have to pay for is the PVC pipe and fittings. I will probably total less than $50 for that and the rest is just stuff that I can collect as scrap or low price salvage (like the container). The container is a blemished or defect item from the factory so it is basically a throw away unit.

What do you think, M? Can you visualize this tank and how I intend it to work?

Catfish

(Good to be back and spring is almost here! )

 

[Mucky_Waters]

Catfish
I always like DIY projects, and building a better settling chamber, or "muck dropper" as you call it sounds like a worthwhile one, except I see what I would consider a flaw in your system..
I'm also text handicapped,,, meaning I understand things better with pictures or diagrams, but from what I can understand of your described system, the thing that I think would handicap your system is your muck blender.
The idea of the settling chamber is to do as you have described, get the muck to drop, or settle, to the bottom of the chamber. Any muck from your pond that will settle to the bottom of the settling chamber will also be wanting to settle to the bottom of your pond where, from my understanding of your description, is where your pump will be. That I see as your biggest handicap. Any muck that is wanting to settle will get stirred and blended up by the pump before entering your settling chamber, and that will severely reduce it's effectiveness. This is why I am such an advocate of gravity feed bottom drains.
I think if you must pump from your pond, you'd have more success trying to build some sort of DIY sieve that a settling chamber, since sieves are more effective at removing suspended muck than settling chambers.
Don't mean to cut down your design, but to me blending the muck up and then immediately trying to get it to settle out again seems counter productive.
Of course, maybe I missed something and it is a gravity fed settling chamber???

 

[shakaho]

I understand, and I like it. Those vertical pipes are such a clever idea. The hard part will be fitting that plate. I'm eager to see how this works.

 

[Catfishnut]

Mucky_Waters,

You make an excellent point. Using the pump to feed the settling chamber is counterproductive. Gravity feed would be best in this case, unfortunately I think I am stuck with using pumps.
That is unless I can engineer something above ground to elevate my pond / tank. It is 1,000 gallons, so this might prove complicated.

Since I am constructing this for my cabin along the river I need to put everything above ground to prevent problems from flooding.
I have built up the land about 3-5 feet so that flood water height will be minimized. That required approximately 2,500 cubic yards of soil and quite a job!
I cannot bring in more soil to build up the landscape any further due to flood zoning restrictions.
The threat of flooding still exists, but I should only see a maximum of 4-6 inches depth. That precludes me from installing anything below grade which really complicates my whole system design.

I would love to use gravity feed for water flow as well as take advantage of the ground temperature during both summer and winter to keep a better balance in the pond/tanks.
But I think you can see my dilemna. It wouldn't be easy to elevate the pond and it isn't wise to excavate down for the filters.

A sieve filter might be the way to go here. Or at least maybe I could incorporate that into the design of my "muck-dropper" to take advantage of both aspects.
A possibility would be to pump the dirty water out of the pond with a higher volume pump to an elevated sieve filter and then let the outflow of the sieve filter gravity feed my muck dropper.

Catfish

 

[Catfishnut]

Update and questions:

After researching a sieve filter system further, I am contemplating incorporating one into my menagerie. My question now involves the SS screen.

I have read many references to a 200, 250 or 300 micron screen (70, 60 or 50 mesh). I assume that anywhere in this range would be suitable, but not any finer or any
more coarse.

What is recommended regarding the type of weave? (Plain weave, twilled weave, intercrimped weave, plain Dutch, reverse Dutch, twilled Dutch, sintered or welded)?
I don't even have a clue what all these weaves are! Although I am pretty sure that sintered is not a good choice. Is there any guidelines for this in a sieve construction?

What about the type of SS (T-304, T-316 or T-316L). I assume the T-316L would probably be best.

And then, does anyone know of a good source to purchase SS filter mesh at a fair price?

One final question for this post. Has anyone ever used nylon or polyethylene mesh - like a filter sock material?
I can get some nylon mesh for free, but it is 150 microns or finer, I think it may be 100 microns. I tried a swatch of it the other day in the sink and the water doesn't seem
to flow very freely through it. It would be a lot less expensive to buy nylon mesh (if it were 200-300 microns) than SS, if it would hold up. What I have won't do the job,
but it may have other potential merits.


Thanks,

Catfishnut

 

[multifasited]

Poly and kevlar ,and SS are commonly used in the paper mills for filteration of the pulp ,all hold up well even w/ the acidic nature of the process!

 

[Catfishnut]

Multifasited,

Thank you for the reply on the material type. I hadn't thought of Kevlar. Poly, nylon and SS seem to be more common. I have decided to go with the SS as I am going to shape it into a cone. More on that later.
I ended up ordering a 48" x 48" panel of T-304 SS 200 micron mesh with Dutch Twilled weaving. It was $220.00 with tax and shipping.

Here is my latest idea, which is subject to change at any time.

55 gallon cylindrical tank, 22" diameter and 35" height.

At approximately 20" from the bottom of the tank, there will be installed a circular "shelf" or ring approximately 6"-8" wide around the perimeter of the interior of the tank.
Within this ring or shelf, there will be open circular insets to hold 4" diameter X 14" long poly mesh 100 micron filter bags.
The inside perimeter of this ring or shelf will have a 2" lip attached as a sort of dam to prevent water from directly flowing into the center of the tank, all water that falls upon the shelf must exit through the poly filter bags.
If the filter bags are not cleaned and become clogged, then the dam will act as a spillway and the water will overflow into the center of the main tank.

Above the filter bag shelf, the SS filter media will be shaped into a cone that has a bottom diameter of approximately 18". The height of the cone will be approximately 12". The top of the cone will be an opening of 4" to 6" in diameter and attach to a PVC tubing. The outer diameter of this PVC tubing will be drilled with many holes to let the incoming, dirty water flow out and drop onto the top of the SS cone. Most of the water will flow right through the cone and to the bottom of the tank, where the drain will be located and route the cleaned water to the bio-conversion tank via a pump.

Any water that does not immediately strain through the SS cone filter will carry the muck away to the bottom of the cone filter and land upon the filter bag shelf, where the debris and muck will be trapped by the filter bags and the water will pass on through the filter bags to the bottom of the tank to join the rest of the water already filtered by the SS cone.

No water is wasted or expelled to remove the debris, it is separated from the muck and cycled back into the stream flow of this mechanical filter system. All of the mechanical filtration is accomplished within one cylindrical 55 gallon tank with no loss of water. Multiple filter socks can be installed around the perimeter of the shelf so they should be able to run for long periods between cleaning cycles.

On paper, my initial crude sketch of this sieve filter doesn't allow for easy changout / cleaning of the filter bags. Because the SS cone filter overhangs the filter bag shelf, it would have to be removed to access the filter bags. I couldn't think of any other way to design it to take full advantage of the self cleaning SS cone filter design within the dimensional space allowed within a 22" diameter tank. If I reduce the base diameter of the cone to provide easy access to remove the filter bags, then I end up with more of vertical walled cylinder and that won't work. I need the widest cone base diameter so that the water falls through it to the center of the tank and the debris rolls down the outside and drops onto the shelf with the filter bags where it can be caught and pass any wash water on through.

Therefore, instead of the designs for a sieve filter that you have likely seen before, ones with a flat, rectangular spillway design, my proposal here is a cone with the incoming water waterfalling from a central, circular reverse "morning-glory" type chamber at the top of the cone and sheeting down over the exterior wall of the cone to carry away the debris while the clean water can also fall through the cone and be pumped on to the bio-conversion tanks via a drain in the bottom of the 55 gallon tank. I am thinking that this design could be used passively, as with a gravity fed bottom drain or actively and aggessively as with a pump.

I am desperately trying to design my entire pond/filter system to reduce the space and plumbing required as well as making it functional and highly efficient.

If you can grasp my concept merely from my words, what is your assesment of this design? Do you like it? What would you add or change?

Catfishnut

 

[multifasited]

Catfishnut .I too am more pictorial ,the conical shaped bottom ,blurs my image of bottom plates configuration ,of pipes ,filter bags and actual perimeter height space.
SS conical shape to 18" 19" w overlap ,I assume you planning angular cut out of 4'/4' S.S. using diamond shape sieve pattern ,w/one seam to gain length required ,is perimeter secured top and bottom ,that wide a flare unsupported would require very secure top mounting,And secure seam ,these questions and comments may or not apply ,as interrupting written word may be in error ,I am sure you have gone over the flow thru rate,and the exit is much larger than the intake ,I totally understand and applaud you concerns related to getting it as right the first time as possible,This vessel ,save the filter bags should be virtually empty in full operation and require some sort of external mounting and stabilization , feeding your pump activated receiver tank ,the in depth design and safety sizing ,shows you engineering abilities ,Would like to see pix when possible ,as I am sure others would to ,I hope all this made some sort of sense!

 

[Mmathis]

Gordy, at some point I saw a series of YOUTUBE videos where someone made a DIY sieve, and I think it had some sort of overflow [or something -- maybe it wasn't overflow but an actual part of the debris collection???] and stuff was collected into mesh bags. It looked fairly easy to construct, though probably beyond MY abilities. If I can find it [them -- there were several, either as a series or showing progression of the idea....], I'll post.