multimedia filter vs cartridge filter

[koshyeng]

we get industrial water from outside company in houston. Though they claim they dont see any scale deposits in their facility, we find large scales ( calcium scales) in our pipeline at the strainer.

I have decided to install a filter ( pH 9.0) in our line to capture anything greater than 20 micron solids. turbidity of water is 4.0 units.

I got quotes for self cleaning cartridge filter and sand filter with automatic backwash.

How should I chose the best equipment for my application. I dont have much experience in this area.

Seniors, plz guide how to choose right one. Thank you

 

[quark]

There is some confusion here. Scale formation is due to dissolved solids (hardness of water) and both the filters you mentioned take care of suspended solids. Go for a softener if you problem is with calcium hardness.

 

[koshyeng]

Thanks Quark.

Our water total hardness is 40 ppm. We are dealing with suspeneded scales that precipitated in the pipieline i.e, we want to remove only suspended solids in the water.

How do I choose between sand filter and cartridge filter. Even if I install a softener, I need to do some pre treatment before softener. which one would be a good choice for pre treatment.

Appreciate your comments.

 

[bimr]

Before you decide, one has to knwo what the application is. What is the water used for?

For example, is the water to be used for fire fighting, or for a beverage to be consumed. The use for the water is just as important as the water supply quality.

 

[tomwalz]

We build filter units that filter down to 1 micron and below. None of the information we found really made any sense in actual tests. We ended up building units, running them in test shops and then doing laser particle counts to get accurate data.

The best guy I have ever met for tech support is Jon at D.R. Shannon. Really knows his stuff.

Jon
D. R. Shannon
23407 Pacific Hwy. So.
Des Moines, WA 98198
USA
(800)255-1032

No connection - he is jsut a great supplier for us.

Thomas J. Walz
Carbide Processors, Inc.

http://www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

 

[koshyeng]

Thanks for your posts. We use this water for our cooling towers. We do have chemical treatment for cooling tower downstream water. Make up water contains so much scale deposits that it sometimes clog our lines.

I want to install a auto clean HYDAC filter or sand filter in this line before it branches out to 4 cooling towers.

I hope I made it clear now. In future we may have softeners for this water so I need to foresee future and select the right tecnology i.e, HYDAC cartridge vs sand filter.

Thank YOu

 

[bimr]

The most practical and economical approach for cooling towers is to use a sidestream filtration approach.

Size the filter for 5% of the recirculating water flow rate.

You can also use the water softener in a sidestream mode as well. Operate the water softener is series with the filter prior to the water softener. To fix the scale problem, you have to install a water softener and/or increase the CT blowdown rate.

This is an application for a media filter, typically sand/anthracite, not an application for a cartridge filter.

 

[sbush]

From what you've described, I'd recommend cartridge filters over sand. Even though the sand filter would have no trouble removing all of the scale particles, it is likely that some, if not all, particles of scale will remain in the sand filter due to their density, and not be backwashed out of the filter even at high (15 - 20 gpm/sf) upflow rates. (This routinely happens with sand filters installed after lime-soda softeners where no post pH adjustment has been included prior to sand filtration.)

I'd install the cartidge filter on the make-up water line, if this is the source water containing the scale particles.

There are some back-flushable strainer devices that might work equally as well (search Amiad or Orival brands). I have never used these devices myself, but they are promoted for just this type of application and would eliminate cartridge replacement (labor and expendables).

S. Bush

http://www.water-eg.com

 

[mxmaciek]

Cartridges replacement cost in the systems with high scaling factor can exceed the filters price within 6 mths.
Remember, that you have to clean your cartridges by the backwash only.
But the possible option can be the screen filters, i.e from Amiad.
You can clear your screens much more efficiently.