Interesting find about Catalytic carbon

[nfored]

http://www.thewaterexchange.net/chloramine-water-filters.htm

I was reading that page and found three things, first thing is the funny miss spelling of koi.

"Ammonia, even in very low levels, is a problem for tropical fish owners and those with Coy ponds. "

The second the crazy idea that tripling the amount of chlorine will alter the chloramine and remove the ammonia. I don't know if this is true but if it is then this is an interesting Idea, chlorine is inline injectable and easier to remove.

One solution offered by an engineer at Calgon Carbon, the manufacturer of catalytic carbon designed to reduce chloramines, is to add triple the amount of chlorine to your water which would change the chloramines and the ammonia would be removed.

Third and most interesting, the Catalytic GAC carbon used in ALL chloramine filters is made by one company.

But Catalytic Carbon GAC (granulated activated carbon) in a special formulation, manufactured by Calgon Carbon, is effective in reducing chloramines taste and odor in a single cartridge.

vising the manufactures pages yielded this pdf on Chlormaine removal, very interesting read.

 

[12 Volt Man]

activiated carbon has always adsorbed chlorine ions and chloramine but the issue in an aquarium is that it takes a lot of contact time for it to adsorb all of it.

by then, it may have done its damage to fish.

still, its always good to add a fresh carbon if you are reintroducing an ornament that you have soaked in a bleach water solution to get rid of algae or disinfect etc.

 

[12 Volt Man]

The second the crazy idea that tripling the amount of chlorine will alter the chloramine and remove the ammonia

yes, its is a crazy idea. and not true lol.

adding chlorine in excess just means you have lots of free chlorine residual in the water. chlorine loves to react with just about anything. especially fish gills..haha

it won't do anything to the chloramine molecules already formed.

what will happen though is if you introduce chlorine into water that has ammonia in it it will form chloramine of course. not as good of a disinfectant as free chlorine but it lasts a long time in the water. thats why water plants form it - so the water stays disinfected from the time it leaves the treatment plant to the time it comes out of your tap.

 

[nfored]

So as I read this article I notice a couple things.

1
That the finer the carbon the better it works.

2
That contact time can be short, as this works very fast, but a longer contact time dramatically extends the performance of the carbon. a 3x increase in contact time results in a 44x increase in performance.


3
Temperature is also a big deal. Preheating the water extends the carbons life and performance. 22C seems to be what they recommend.

 

[nfored]

yes, its is a crazy idea. and not true lol.

adding chlorine in excess just means you have lots of free chlorine residual in the water. chlorine loves to react with just about anything. especially fish gills..haha

it won't do anything to the chloramine molecules already formed.

what will happen though is if you introduce chlorine into water that has ammonia in it it will form chloramine of course. not as good of a disinfectant as free chlorine but it lasts a long time in the water. thats why water plants form it - so the water stays disinfected from the time it leaves the treatment plant to the time it comes out of your tap.

Hopefully we all filter out chlorine, I agree though thats an insane idea but the real meat of this post is the pdf on chloramine.

 

[nfored]

This explanation helped me under stand the EBCT discussed in the pdf, I got this description from this page

The empty bed contact time using a general-purpose carbon should be at least 15 minutes (2 gpm per cubic foot) and the superficial flow rate should not exceed 2 gpm per square foot.

The empty bed contact time (EBCT) measures contact between carbon particles and water as the water flows through the vessel. Fifteen minutes is the minimum EBCT required to maximize the carbon capability to remove chloramines.

EBCT is calculated from the following:

EBCT = Volume of Activated Carbon in the Vessel divide by
Flow Rate of the Water
For this equation to result in minutes, the flow rate typically expressed in gallons per minute (gpm) must be converted to units such as cubic feet/ minutes (ft3/min). The conversion is 1gpm = .13368 ft3/min.

Below is an example calculation of EBCT:

Carbon vessel: 10 cubic feet
Flow rate: 8 gpm

EBCT = 10 ft^3 / ( 4 gpm x .13368) = 18.7 minutes

 

[nfored]

Here is a better explanation page

where V= the Volume of Carbon (in cubic
feet) and Q= the water flow rate, in cubic feet per minute.

For example, if you know that you have a flow rate of 10 Gallons per Minute (GPM), and
you want an EBCT of 5 minutes, your calculation would be:
V = (Q * EBCT) / 7.48
V = (10 * 5) / 7.48
V = 6.69
You need a 6.69 cubic foot carbon tank for each working and polishing tank

To calculate your EBCT from a known carbon tank volume and flow rate (assume a 6
cubic foot tank and a 12 GPM flow rate), your calculation would be:
Monitoring Your Dialysis Water Treatment System - June 2005
Northwest Renal Network - CMS Contract #500-03-NW16
7
EBCT = V/Q
EBCT = 6 / (12/7.48)
EBCT = 6 / 1.6
EBCT = 3.75 minutes per 6 cubic foot tank


It seems most of the choramine filters use 2 10" cartridges so (10" x 2.5") about 196 cubic inches or 0.11 cubic feet. 1 gpm = 0.13 cubic feet per minute, so assuming a 1 gph drip emitter I come up with this

0.00214 Cubic Feet per minute (flow rate)
0.11 cubic feet (carbon volume)

0.11 / 0.00214 = 51.4 EBCT Given that our water is in contact for 51.4 minutes and the pdf shows it can reduce it in as little as 2 minutes I would say you could have a much higher drip rate.



From the same page above here is a great explanation of measuring chloramine

There is no
method to test directly for chloramine, so you must perform two separate tests: one for
Total Chlorine, and one for Free Chlorine. The chloramine level is the difference between
the two tests.
Example:
Your Measured Total Chlorine is 1.2 PPM
Your Measured Free Chlorine is 0.8 PPM
1.2 - 0.8 = 0.4 PPM
Therefore your Chloramine Level is 0.4 PPM

A little clarification this is about treating incoming water, not water in your tank.

 

[Danger_Chicken]

thanks for the info

 

[Pharaoh]

Good read.