Water Softeners and Air Filtration Systems - brown water after backwash
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Dave-O
01-03-07, 02:39 PM
I have a filter system disigned for high iron 11ppm, low ph 5.8 and positive for coliform. The system injects a measured amount of bleach and then into a large pressure tank to kill the bacteria and ppt the iron. Then into a 2 cf resin tank of Filter Ag that is controlled by a automatic filter control valve from watersoft. Then into a second resin tank with a mixture of activated carbon to remove the residual bleach and calcite to raise the Ph.
The big problem I am currently having is when the filter Ag tank backwashes I get brown water after the backwash is complete. I have resorted to backwashing the tanks only when I can watch them to make sure everything is OK. Once I have started the backwash cycle manually I stand there and watch it, to see what is happening, it cycles through the rinse and then backwash and then second rinse with what seems like adequate water flow, and I can see very dirty/red water in the backwash line during the backwash part of the cycle. I bypass the second carbon tank when I do this to avoid introducing the iron ppt into that tank. It just seems like the backwash cycle is not allowing the control valve to get to a point where the tank is filtering properly after the cycle. If, after I backwash the tank, I let the water flow out the garden hose for a long time ~30 minutes I can get the water to a point where it is no longer discolored or very slightly so, then I un-bypass the second carbon tank and I am OK for the next few days until I want to backwash the filter Ag tank again. I understand that the waterfsoft control valve is simply a re-badged Fleck changed a bit to reduce water use. I am frustrated by the lack of help/information and availability from watersoft, and am wondering about installing Fleck replacement parts in the head e.g the piston and spacer stack but am unsure of this. I am fairly certain that these parts may be the source of my problem, i.e water not flowing properly during the backwash cycle.
The big problem I am currently having is when the filter Ag tank backwashes I get brown water after the backwash is complete. I have resorted to backwashing the tanks only when I can watch them to make sure everything is OK. Once I have started the backwash cycle manually I stand there and watch it, to see what is happening, it cycles through the rinse and then backwash and then second rinse with what seems like adequate water flow, and I can see very dirty/red water in the backwash line during the backwash part of the cycle. I bypass the second carbon tank when I do this to avoid introducing the iron ppt into that tank. It just seems like the backwash cycle is not allowing the control valve to get to a point where the tank is filtering properly after the cycle. If, after I backwash the tank, I let the water flow out the garden hose for a long time ~30 minutes I can get the water to a point where it is no longer discolored or very slightly so, then I un-bypass the second carbon tank and I am OK for the next few days until I want to backwash the filter Ag tank again. I understand that the waterfsoft control valve is simply a re-badged Fleck changed a bit to reduce water use. I am frustrated by the lack of help/information and availability from watersoft, and am wondering about installing Fleck replacement parts in the head e.g the piston and spacer stack but am unsure of this. I am fairly certain that these parts may be the source of my problem, i.e water not flowing properly during the backwash cycle.
AndyC
01-04-07, 08:19 AM
Your problem is not so unusual....
When you say 'watersoft' (in lower case letters), I assume you are speaking of the name of the company, which is a local company, right?
A number of red flags show up here
....First of all, your disinfection system may be very inadequate. You say you inject bleach (5.25% household bleach?) prior to a 'large' pressure tank, presumably for mixing, disinfection and iron conversion from ferrous to ferric.
What type of pump are you using? Diaphram (pulse) or paristaltic (siphon)?
How large is your pressure tank? How many downflow gallons. In other words, if you have a 30 gallon tank, your down flow may be 9-14 gallons depending on bladder pressure. That is not a very large volume of water and it is constantly fluctuating. There is essentially no 'retention' of water except when not in service. This means you need higher levels of chemical to be effective.
For disinfection using chlorine, I would recommend you need a minimum of 20 minutes of retention time and it woud seem very unlikely that can be achieved through a pressure tank constantly expanding and contracting during service.
Secondly, one problem with single tank backwashing filters is that they backwash with all the same water (very heavy iron-mix of ferrous and ferric iron) that you are trying to treat. Meaning, when you are cleaning out the old iron from the service cycle, you are replacing it with more of the same. So when you place it back into service, it all flushes into your home as dirty brown water until it clears awaya and resumes normal service.
this is not an ideal set up.
I am not quite sure why your pressure seems to drop when you by-pass the carbon filter. Are you running water to the house at that time? Can't figure that out with the info provided, sorry.
Now what is the system doing to your iron? Bleach is an effective oxidizer but only when time alottment is adequate and/or solution concentration is sufficient. It could be that it is -partially converted- by the time it reaches the ag filter and yet much may remain as dissovled iron as it passes through and enters the carbon filter valve. If you disassemble the carbon filter valve and notice iron deposits, then that is what's happening. Carbon will have virtually no effect of iron, so it will pass on through to the house.
If your iron is passing through unaffected, then there may be chance that the coilform may be doing the same. Watersoft should be addressing these issues as they are responsible for your system.
I advise to install a 120 gallon retention tank (6gpm x 20min + 120gl) with an in-line mixer between the pressure tank and the backwashing filter. There are some mixing tank that are much smaller and they are fine for iron, pH and other water issues, but when mixed with disinfection, the actual time involved is very important.
This serves numerous important purposes:
1. it converts iron (manganese, odors) more efficiently,
2. better disinfects the water,
3. provides an area for the ppt iron to collect,
4. allows the ag filter to backwash with 'cleaner' water,
5. simply flushing the retention tank is easy maintenance,
6. you can avoid constantly supplying bleach to the bladder tank (rubber and chlorine are not good buddies),
7. you can easily monitor free-chlorine through a test valve after the retention tank and ag filter and adjust supply accordingly,
8. your ag filter won't need to backwash as often, and
9. you filter ag and carbon filter media and valves may last much longer, work more effectively and cost less over the maintenance period,
10. use less chemical solution, generally, the longer the retention time the less bleach is needed.
Just food for thought
Space (120 gallon tank and plumbing) is often a bigger hurdle than cost because there is no reason not to save money over the long haul with a system that is properly set up and works.
Andy CWS
When you say 'watersoft' (in lower case letters), I assume you are speaking of the name of the company, which is a local company, right?
A number of red flags show up here
....First of all, your disinfection system may be very inadequate. You say you inject bleach (5.25% household bleach?) prior to a 'large' pressure tank, presumably for mixing, disinfection and iron conversion from ferrous to ferric.
What type of pump are you using? Diaphram (pulse) or paristaltic (siphon)?
How large is your pressure tank? How many downflow gallons. In other words, if you have a 30 gallon tank, your down flow may be 9-14 gallons depending on bladder pressure. That is not a very large volume of water and it is constantly fluctuating. There is essentially no 'retention' of water except when not in service. This means you need higher levels of chemical to be effective.
For disinfection using chlorine, I would recommend you need a minimum of 20 minutes of retention time and it woud seem very unlikely that can be achieved through a pressure tank constantly expanding and contracting during service.
Secondly, one problem with single tank backwashing filters is that they backwash with all the same water (very heavy iron-mix of ferrous and ferric iron) that you are trying to treat. Meaning, when you are cleaning out the old iron from the service cycle, you are replacing it with more of the same. So when you place it back into service, it all flushes into your home as dirty brown water until it clears awaya and resumes normal service.
this is not an ideal set up.
I am not quite sure why your pressure seems to drop when you by-pass the carbon filter. Are you running water to the house at that time? Can't figure that out with the info provided, sorry.
Now what is the system doing to your iron? Bleach is an effective oxidizer but only when time alottment is adequate and/or solution concentration is sufficient. It could be that it is -partially converted- by the time it reaches the ag filter and yet much may remain as dissovled iron as it passes through and enters the carbon filter valve. If you disassemble the carbon filter valve and notice iron deposits, then that is what's happening. Carbon will have virtually no effect of iron, so it will pass on through to the house.
If your iron is passing through unaffected, then there may be chance that the coilform may be doing the same. Watersoft should be addressing these issues as they are responsible for your system.
I advise to install a 120 gallon retention tank (6gpm x 20min + 120gl) with an in-line mixer between the pressure tank and the backwashing filter. There are some mixing tank that are much smaller and they are fine for iron, pH and other water issues, but when mixed with disinfection, the actual time involved is very important.
This serves numerous important purposes:
1. it converts iron (manganese, odors) more efficiently,
2. better disinfects the water,
3. provides an area for the ppt iron to collect,
4. allows the ag filter to backwash with 'cleaner' water,
5. simply flushing the retention tank is easy maintenance,
6. you can avoid constantly supplying bleach to the bladder tank (rubber and chlorine are not good buddies),
7. you can easily monitor free-chlorine through a test valve after the retention tank and ag filter and adjust supply accordingly,
8. your ag filter won't need to backwash as often, and
9. you filter ag and carbon filter media and valves may last much longer, work more effectively and cost less over the maintenance period,
10. use less chemical solution, generally, the longer the retention time the less bleach is needed.
Just food for thought
Space (120 gallon tank and plumbing) is often a bigger hurdle than cost because there is no reason not to save money over the long haul with a system that is properly set up and works.
Andy CWS
Dave-O
01-05-07, 12:51 PM
Thanks, a lot of information there, I guess my questions were not so clear
Your problem is not so unusual....
When you say 'watersoft' (in lower case letters), I assume you are speaking of the name of the company, which is a local company, right?
***************
No, the control valves are from WaterSoft Inc. called "2092 control valve" which I understand is now Amtrol, anyway they are just re-badged Fleck 5600 with a bit of tweaking of the inards. I looked at the Fleck information to try and get more information about the WaterSoft mods. The backwash time is considerably shorter and the spacer stack and piston are different.
***************
A number of red flags show up here
....First of all, your disinfection system may be very inadequate. You say you inject bleach (5.25% household bleach?) prior to a 'large' pressure tank, presumably for mixing, disinfection and iron conversion from ferrous to ferric.
What type of pump are you using? Diaphram (pulse) or paristaltic (siphon)?
How large is your pressure tank? How many downflow gallons. In other words, if you have a 30 gallon tank, your down flow may be 9-14 gallons depending on bladder pressure. That is not a very large volume of water and it is constantly fluctuating. There is essentially no 'retention' of water except when not in service. This means you need higher levels of chemical to be effective.
For disinfection using chlorine, I would recommend you need a minimum of 20 minutes of retention time and it woud seem very unlikely that can be achieved through a pressure tank constantly expanding and contracting during service.
*********************
Yes, injecting household bleach in line via a Stenner peristaltic pump before a UT80 retention tank from WellMate for the purposes of disinfection and iron oxidation. I have the amount of bleach set for a residual of 2.0 measured after the Ag tank and before the carbon tank.
************************
Secondly, one problem with single tank backwashing filters is that they backwash with all the same water (very heavy iron-mix of ferrous and ferric iron) that you are trying to treat. Meaning, when you are cleaning out the old iron from the service cycle, you are replacing it with more of the same. So when you place it back into service, it all flushes into your home as dirty brown water until it clears awaya and resumes normal service.
**************************
I had that thought also, but didn't really know what if anything I could do about it, but thought it shouldn't matter because the last part of the backwash cycle on the WaterSoft control valve is a "settling rinse" which is supposed to flow water in the normal "in serv" position (out the backwash drain line) to "re-set" the filter bed and allow it to supply filtered water immediately upon returning to service.
************************
this is not an ideal set up.
I am not quite sure why your pressure seems to drop when you by-pass the carbon filter. Are you running water to the house at that time? Can't figure that out with the info provided, sorry.
*********************
No pressure loss. Since I started having problems, I bypass the carbon filter while the Ag tank is backwashing and until I can get clear water again eg from the garden hose. I do this so I do not introduce any unfiltered iron containing water into the carbon tank.
*************************
Now what is the system doing to your iron? Bleach is an effective oxidizer but only when time alottment is adequate and/or solution concentration is sufficient. It could be that it is -partially converted- by the time it reaches the ag filter and yet much may remain as dissovled iron as it passes through and enters the carbon filter valve. If you disassemble the carbon filter valve and notice iron deposits, then that is what's happening. Carbon will have virtually no effect of iron, so it will pass on through to the house.
**************************
I believe I have sufficient bleach to disinfect and ppt the iron as I can measure significant (2.0, sorry I don't remember the units) chlorine residual after the Ag tank...even when the Ag tank is passing "brown water".
I think a problem is that the control valve on the Ag tank is either not flowing enough water during the "settling rinse" or is not always returning the piston to its proper positon after a backwash and somehow allowing a little bit of unfiltered water through along with the filtered water. I am frustrated with the help/information I can get about the WaterSoft "2092 control valve" but realize that it is really just a Fleck. I was thinking about substituting some of the parts eg piston/spacer stack from Fleck rather than using the WaterSoft parts. WaterSoft redesigned the Fleck head "to reduce water consumption and backwash time", neither of which I really care about, I would much rather have a nice long full backwash cycle, especially on the Ag tank with my iron being so high. Maybe my anwer is to just get rid of the WaterSoft head on the Ag tank and replace it with a Fleck.
A shorter/less volume backwash on the carbon tank sounds like a good idea...as far as saving the media. If the Ag tank is doing its job then all the backwash for the carbon tank is doing is "re-setting the bed".
*************************
If your iron is passing through unaffected, then there may be chance that the coilform may be doing the same. Watersoft should be addressing these issues as they are responsible for your system.
I advise to install a 120 gallon retention tank (6gpm x 20min + 120gl) with an in-line mixer between the pressure tank and the backwashing filter. There are some mixing tank that are much smaller and they are fine for iron, pH and other water issues, but when mixed with disinfection, the actual time involved is very important.
This serves numerous important purposes:
1. it converts iron (manganese, odors) more efficiently,
2. better disinfects the water,
3. provides an area for the ppt iron to collect,
4. allows the ag filter to backwash with 'cleaner' water,
5. simply flushing the retention tank is easy maintenance,
6. you can avoid constantly supplying bleach to the bladder tank (rubber and chlorine are not good buddies),
7. you can easily monitor free-chlorine through a test valve after the retention tank and ag filter and adjust supply accordingly,
8. your ag filter won't need to backwash as often, and
9. you filter ag and carbon filter media and valves may last much longer, work more effectively and cost less over the maintenance period,
10. use less chemical solution, generally, the longer the retention time the less bleach is needed.
Just food for thought
Space (120 gallon tank and plumbing) is often a bigger hurdle than cost because there is no reason not to save money over the long haul with a system that is properly set up and works.
Andy CWS
*******************
Thanks for the ideas. Space is not an issue. What is an in-line mixer? Isn't it much easier to deal with dissolved iron with a higher pH, shouldn't the pH problem have been addressed before dealing with the iron? Right now the pH is corrected in the carbon tank with calcite after the iron has already been removed.
Amen to your last statement, I told the guy when he was designing it and I didn't know anything about the subject, "Don't cut any corners, just make it work" I don't do business with him anymore for a variety of reasons, and am now stuck with trying to make the most of the equipment and setup I have. I have also recently re-sampled the raw water for testing by the state lab, things may have changed in the last three years, no sense in changing/buying new equipment unless I know exactly what I am dealing with. Thanks again for the help.
Dave
Your problem is not so unusual....
When you say 'watersoft' (in lower case letters), I assume you are speaking of the name of the company, which is a local company, right?
***************
No, the control valves are from WaterSoft Inc. called "2092 control valve" which I understand is now Amtrol, anyway they are just re-badged Fleck 5600 with a bit of tweaking of the inards. I looked at the Fleck information to try and get more information about the WaterSoft mods. The backwash time is considerably shorter and the spacer stack and piston are different.
***************
A number of red flags show up here
....First of all, your disinfection system may be very inadequate. You say you inject bleach (5.25% household bleach?) prior to a 'large' pressure tank, presumably for mixing, disinfection and iron conversion from ferrous to ferric.
What type of pump are you using? Diaphram (pulse) or paristaltic (siphon)?
How large is your pressure tank? How many downflow gallons. In other words, if you have a 30 gallon tank, your down flow may be 9-14 gallons depending on bladder pressure. That is not a very large volume of water and it is constantly fluctuating. There is essentially no 'retention' of water except when not in service. This means you need higher levels of chemical to be effective.
For disinfection using chlorine, I would recommend you need a minimum of 20 minutes of retention time and it woud seem very unlikely that can be achieved through a pressure tank constantly expanding and contracting during service.
*********************
Yes, injecting household bleach in line via a Stenner peristaltic pump before a UT80 retention tank from WellMate for the purposes of disinfection and iron oxidation. I have the amount of bleach set for a residual of 2.0 measured after the Ag tank and before the carbon tank.
************************
Secondly, one problem with single tank backwashing filters is that they backwash with all the same water (very heavy iron-mix of ferrous and ferric iron) that you are trying to treat. Meaning, when you are cleaning out the old iron from the service cycle, you are replacing it with more of the same. So when you place it back into service, it all flushes into your home as dirty brown water until it clears awaya and resumes normal service.
**************************
I had that thought also, but didn't really know what if anything I could do about it, but thought it shouldn't matter because the last part of the backwash cycle on the WaterSoft control valve is a "settling rinse" which is supposed to flow water in the normal "in serv" position (out the backwash drain line) to "re-set" the filter bed and allow it to supply filtered water immediately upon returning to service.
************************
this is not an ideal set up.
I am not quite sure why your pressure seems to drop when you by-pass the carbon filter. Are you running water to the house at that time? Can't figure that out with the info provided, sorry.
*********************
No pressure loss. Since I started having problems, I bypass the carbon filter while the Ag tank is backwashing and until I can get clear water again eg from the garden hose. I do this so I do not introduce any unfiltered iron containing water into the carbon tank.
*************************
Now what is the system doing to your iron? Bleach is an effective oxidizer but only when time alottment is adequate and/or solution concentration is sufficient. It could be that it is -partially converted- by the time it reaches the ag filter and yet much may remain as dissovled iron as it passes through and enters the carbon filter valve. If you disassemble the carbon filter valve and notice iron deposits, then that is what's happening. Carbon will have virtually no effect of iron, so it will pass on through to the house.
**************************
I believe I have sufficient bleach to disinfect and ppt the iron as I can measure significant (2.0, sorry I don't remember the units) chlorine residual after the Ag tank...even when the Ag tank is passing "brown water".
I think a problem is that the control valve on the Ag tank is either not flowing enough water during the "settling rinse" or is not always returning the piston to its proper positon after a backwash and somehow allowing a little bit of unfiltered water through along with the filtered water. I am frustrated with the help/information I can get about the WaterSoft "2092 control valve" but realize that it is really just a Fleck. I was thinking about substituting some of the parts eg piston/spacer stack from Fleck rather than using the WaterSoft parts. WaterSoft redesigned the Fleck head "to reduce water consumption and backwash time", neither of which I really care about, I would much rather have a nice long full backwash cycle, especially on the Ag tank with my iron being so high. Maybe my anwer is to just get rid of the WaterSoft head on the Ag tank and replace it with a Fleck.
A shorter/less volume backwash on the carbon tank sounds like a good idea...as far as saving the media. If the Ag tank is doing its job then all the backwash for the carbon tank is doing is "re-setting the bed".
*************************
If your iron is passing through unaffected, then there may be chance that the coilform may be doing the same. Watersoft should be addressing these issues as they are responsible for your system.
I advise to install a 120 gallon retention tank (6gpm x 20min + 120gl) with an in-line mixer between the pressure tank and the backwashing filter. There are some mixing tank that are much smaller and they are fine for iron, pH and other water issues, but when mixed with disinfection, the actual time involved is very important.
This serves numerous important purposes:
1. it converts iron (manganese, odors) more efficiently,
2. better disinfects the water,
3. provides an area for the ppt iron to collect,
4. allows the ag filter to backwash with 'cleaner' water,
5. simply flushing the retention tank is easy maintenance,
6. you can avoid constantly supplying bleach to the bladder tank (rubber and chlorine are not good buddies),
7. you can easily monitor free-chlorine through a test valve after the retention tank and ag filter and adjust supply accordingly,
8. your ag filter won't need to backwash as often, and
9. you filter ag and carbon filter media and valves may last much longer, work more effectively and cost less over the maintenance period,
10. use less chemical solution, generally, the longer the retention time the less bleach is needed.
Just food for thought
Space (120 gallon tank and plumbing) is often a bigger hurdle than cost because there is no reason not to save money over the long haul with a system that is properly set up and works.
Andy CWS
*******************
Thanks for the ideas. Space is not an issue. What is an in-line mixer? Isn't it much easier to deal with dissolved iron with a higher pH, shouldn't the pH problem have been addressed before dealing with the iron? Right now the pH is corrected in the carbon tank with calcite after the iron has already been removed.
Amen to your last statement, I told the guy when he was designing it and I didn't know anything about the subject, "Don't cut any corners, just make it work" I don't do business with him anymore for a variety of reasons, and am now stuck with trying to make the most of the equipment and setup I have. I have also recently re-sampled the raw water for testing by the state lab, things may have changed in the last three years, no sense in changing/buying new equipment unless I know exactly what I am dealing with. Thanks again for the help.
Dave