DIY Sulfur Denitrator

[dartier]

Small RO/DI canister based denitrator reactor

Small RO/DI canister based denitrator reactor

Before I start this unit up, I thought I would post to get feedback. I am hopeful that my design will allow the Nitrogen to off gas through the ARM canister (though there is a manual vent button just incase).

The unit is comprised of 2 RO/DI cannisters, with the first holding the LSM (I plan on laying some bags of Matrix on top of the LSM), and the second will hold ARM. I will be using a Milwaukee MC125 PH/ORP controller to control the feed pump. The circulation pump is a Jebao DC1200 and the feed pump is a Jebao DC2000. I will probably switch to a DC1200 feed pump later, but only have a DC2000 on hand at the moment.

There is a check valve on the input and on the output of the LSM canister. I am running the canisters in reverse with a PVC tube to get an upflow effect. This will be running in the sump. The Jebao pumps are not external capable.

Ignore the stand in Chinese PH probe in the photos, I did not want to unwrap the Milwaukee ORP probe.

This shows the whole system

Here is a close up of the recirculation flow.

The PVC tube is just pressure fitted (not glued) so that it can be adjusted for length. The tube uses a slip x slip on the bottom and a slip x FPT on the top. The FPT end slides over nub on the canister lid snuggly. I also put an o-ring on the nub for the union to seat/seal against. I just made some slits on my mitre saw. I thought about making an acrylic diffusion disc on my CNC to rest on the shoulder of the slip union, but decided against it since it would leave a lot of unused space a the bottom of the cannister. If I get too much channelling, I guess I could make a disc that slips over the union and includes standoffs to set the space below it. For now I will include a plastic mesh needlepoint disc in between the LSM and the Matrix bags just to hold the LSM down in the flow.

I included plenty of unions so that it can be easily broken down for maintenance. I learned from past DIY projects that were too permanent and very hard to maintain . I also used threaded fittings so if it ends up being a bust, I can disassemble the unit and re-use most of the parts.

Here is a top down shot showing the reverse flow and the manual vent buttons. Hopefully the stainless screws hold up well in salt water. If they prove problematic I will remove them and seal the holes.

I plan on starting it up later today off line in a barrel using tank water to allow it to cycle.

Dennis

 

[Belgian Anthias]

Before I start this unit up, I thought I would post to get feedback. I am hopeful that my design will allow the Nitrogen to off gas through the ARM canister (though there is a manual vent button just incase).

The unit is comprised of 2 RO/DI cannisters, with the first holding the LSM (I plan on laying some bags of Matrix on top of the LSM), and the second will hold ARM. I will be using a Milwaukee MC125 PH/ORP controller to control the feed pump. The circulation pump is a Jebao DC1200 and the feed pump is a Jebao DC2000. I will probably switch to a DC1200 feed pump later, but only have a DC2000 on hand at the moment.

There is a check valve on the input and on the output of the LSM canister. I am running the canisters in reverse with a PVC tube to get an upflow effect. This will be running in the sump. The Jebao pumps are not external capable.

Ignore the stand in Chinese PH probe in the photos, I did not want to unwrap the Milwaukee ORP probe.

Dennis

I can not see the pictures.
What are the expectations concerning nitrate removal for this system? What do you expect it will be capable to do?
Why Matrix?
You are using ORP for controlling the feed pump? The feed pump is rated 900-2000l/h. The circulation pump is rated 400-1200 l/h. The idea is to move the media around very slowly otherwise the biofilm may be washed away.
For having control on the nitrate level flow true the canisters must be controllable from 0 to 10x the volume of the sulphur. Controlling the level is only possible when de system is capable to remove the daily nitrate production daily at the desired nitrate level.
To do this the pumps must be in a closed loop with a control valve to adjust the flow.
When matrix is used the biofilm on this media will not be able to oxidize sulphur when the circumstances to do so are suitable.
ORP and PH can be used for monitoring the system. PH will show the denitrification rate.( nitrification and denitrification produces H+)
What is the volume of sulphur used?

 

[dartier]

Doh. Until you mentioned it I did not realize the photos were marked as private and only showing up to me :headwally: ...

Here they are reposted with their respective explanations. Too late to edit my original post and making them public changed their URL's.

This shows the whole system

Here is a close up of the recirculation flow.

The PVC tube is just pressure fitted (not glued) so that it can be adjusted for length. The tube uses a slip x slip on the bottom and a slip x FPT on the top. The FPT end slides over nub on the canister lid snuggly. I also put an o-ring on the nub for the union to seat/seal against. I just made some slits on my mitre saw. I thought about making an acrylic diffusion disc on my CNC to rest on the shoulder of the slip union, but decided against it since it would leave a lot of unused space a the bottom of the cannister. If I get too much channelling, I guess I could make a disc that slips over the union and includes standoffs to set the space below it. For now I will include a plastic mesh needlepoint disc in between the LSM and the Matrix bags just to hold the LSM down in the flow.

I included plenty of unions so that it can be easily broken down for maintenance. I learned from past DIY projects that were too permanent and very hard to maintain . I also used threaded fittings so if it ends up being a bust, I can disassemble the unit and re-use most of the parts.

Here is a top down shot showing the reverse flow and the manual vent buttons. Hopefully the stainless screws hold up well in salt water. If they prove problematic I will remove them and seal the holes.

I have been running it since yesterday, but so far have had difficulty getting the ORP below 60. I am wondering if I have some leaks on the suction side of the circulation pump. The water level in my test container is lower than it would normally be in my sump. I am not 100% sure but think that air bubbles are building up in the output line to the ARM canister. This bodes well for my self purging idea, but not so well for the hope that the plumbing is not sucking air.

There is only about 1/4 of a gallon of LSM in it currently. I can probably stretch it to 1/2 gallon if I scrap the Matrix. Too early to be disheartened, but I am was kind of expecting the ORP to drop on its own. Then again I may not have much in the water other than nitrate (may be low on organics).

Since I am running it disconnected from the tank, I suppose I could give it a kick start with some carbon to see if the denitrator is capable of holding a low ORP.

Dennis

 

[Belgian Anthias]

Nice build Dartier.
How the flow is regulated as the pumps are not fitted in by a closed loop?
1/2 gal S should be fine in a 120 Gal system to reduce the level to 1ppm if the daily production stays below 0.5 ppm.
Kick start? A sulfur denitrator should work within 24h ( nitrite increase). Full operational and conditioned after 2 weeks. They use anorganic carbon which is normally available. Are you going to put methanol in a sulfur denitrator? If so, why? A sulphur denitrator is NOT a carbon driven heterothrophe denitrator and should be managed otherwise to perform well although it should work.
Is the flow ORP monitored or ORP controlled? Is there enough nitrate available as it is disconnected from the system?
Why matrix? It is a sulfur denitrator!

 

[dartier]

Nice build Dartier.
How the flow is regulated as the pumps are not fitted in by a closed loop?
1/2 gal S should be fine in a 120 Gal system to reduce the level to 1ppm if the daily production stays below 0.5 ppm.
Kick start? A sulfur denitrator should work within 24h ( nitrite increase). Full operational and conditioned after 2 weeks. They use anorganic carbon which is normally available. Are you going to put methanol in a sulfur denitrator? If so, why? A sulphur denitrator is NOT a carbon driven heterothrophe denitrator and should be managed otherwise to perform well although it should work.
Is the flow ORP monitored or ORP controlled? Is there enough nitrate available as it is disconnected from the system?
Why matrix? It is a sulfur denitrator!

I am not sure I understand your question about regulating the flow. The circulation pump's flow (DC1200) can be adjusted with its controller. This pump runs 24x7. The feed pump (DC2000) also has a controller that can be used to regulate the flow. On its lowest setting, and with the 3/4" output being restricted to 1/4" line, the flow is a slow steady stream.

The desire to add carbon was simply to help use up the remaining O2 and get the ORP down to see if the system can hold the ORP down, or if I do in fact have an air leak somewhere causing air to be sucked into the system.

When I woke up this morning the DC1200 was again sucking air and I had to manually enable the feed pump to purge the air pocket. Upon doing that the ORP dropped to 18 from 70, and is still dropping as I write this. This might just be the result of insufficient purging of the internal air upon startup. Maybe I did not let the feed pump run long enough before allowing the controller to take over?

The ORP is controlled not monitored. Though I do stand there starring at the controller more often the I should . There is 50 PPM of nitrate for the system to work on.

The Matrix was an idea that I gleaned from reading the threads on sulfur denitrators (including this one). The premise is that the bacteria can use the Matrix media as place to grow, and still use the sulfur as their food source. In any case, I will most likely remove it and use the space for more sulfur media, just because the reactor is on the small side already.

I am adding the more tank water every day to the test barrel during my water change to try to get the water level as high as my sump (just incase the there is a leak lower than my normal sump level). One more day and I should have 10" of water in the 29Gal test barrel.

Update: ORP now at 11

Dennis

 

[CHSUB]

I am not sure I understand your question about regulating the flow. The circulation pump's flow (DC1200) can be adjusted with its controller. This pump runs 24x7. The feed pump (DC2000) also has a controller that can be used to regulate the flow. On its lowest setting, and with the 3/4" output being restricted to 1/4" line, the flow is a slow steady stream.

The desire to add carbon was simply to help use up the remaining O2 and get the ORP down to see if the system can hold the ORP down, or if I do in fact have an air leak somewhere causing air to be sucked into the system.

When I woke up this morning the DC1200 was again sucking air and I had to manually enable the feed pump to purge the air pocket. Upon doing that the ORP dropped to 18 from 70, and is still dropping as I write this. This might just be the result of insufficient purging of the internal air upon startup. Maybe I did not let the feed pump run long enough before allowing the controller to take over?

The ORP is controlled not monitored. Though I do stand there starring at the controller more often the I should . There is 50 PPM of nitrate for the system to work on.

The Matrix was an idea that I gleaned from reading the threads on sulfur denitrators (including this one). The premise is that the bacteria can use the Matrix media as place to grow, and still use the sulfur as their food source. In any case, I will most likely remove it and use the space for more sulfur media, just because the reactor is on the small side already.

I am adding the more tank water every day to the test barrel during my water change to try to get the water level as high as my sump (just incase the there is a leak lower than my normal sump level). One more day and I should have 10" of water in the 29Gal test barrel.

Update: ORP now at 11

Dennis

are you running flow through the reactor? if yes, i would stop until ORP goes to -200, and then start flow as slow as possible. if ORP is used to control reactor, flow should not start until ORP is ~-170. i have found ORP of -100 or greater(closer to 0) allows no3 in effluent.

 

[dartier]

are you running flow through the reactor? if yes, i would stop until ORP goes to -200, and then start flow as slow as possible. if ORP is used to control reactor, flow should not start until ORP is ~-170. i have found ORP of -100 or greater(closer to 0) allows no3 in effluent.

No, the reactor has been under the control of the controller, so the feed pump was off, while the circulation pump is always on.

When I came home from work, I found that it was hovering at an ORP of 24. I was pretty disappointed that it still had not dropped below 0. I turned on the feed pump manually to watch for bubbles exiting the outflow. It did not seem to expel any air bubbles, but what I did notice though was that the ORP started dropping while the feed pump was running. This seemed counter intuitive, and on a hunch I started to suspect the circulation pump was set too low and was not actually circulating effectively, and the extra pressure from the feed pump was overcoming back pressure, so I adjusted the DC1200 to max, did not see any noticeable change, and then left to go buy some more fittings, intent on dis-assembling the unit to look for leaks tonight.

When I returned an hour later, the ORP was -115 and the controller was cycling the feed pump on and off. Finally!!

I am just working on dialing the controller in. The Milwaukee unit could really
use a digital set point feature. Currently it uses a dial and is quite sensitive to small movements. I have it coming on at -210 and turning off at -190. I would rather have it come on sooner, but I keep overshooting the band and either being too low, or too high for the set point.

The lowest this unit is suppose to be capable of being set to -200 (at the lowest), but the ORP on my unit reads (and turns on) well below that when the dial is set to -200 for the set point. I wonder which is correct, the dial or the probe reading?

Dennis

 

[CHSUB]

No, the reactor has been under the control of the controller, so the feed pump was off, while the circulation pump is always on.

When I came home from work, I found that it was hovering at an ORP of 24. I was pretty disappointed that it still had not dropped below 0. I turned on the feed pump manually to watch for bubbles exiting the outflow. It did not seem to expel any air bubbles, but what I did notice though was that the ORP started dropping while the feed pump was running. This seemed counter intuitive, and on a hunch I started to suspect the circulation pump was set too low and was not actually circulating effectively, and the extra pressure from the feed pump was overcoming back pressure, so I adjusted the DC1200 to max, did not see any noticeable change, and then left to go buy some more fittings, intent on dis-assembling the unit to look for leaks tonight.

When I returned an hour later, the ORP was -115 and the controller was cycling the feed pump on and off. Finally!!

I am just working on dialing the controller in. The Milwaukee unit could really
use a digital set point feature. Currently it uses a dial and is quite sensitive to small movements. I have it coming on at -210 and turning off at -190. I would rather have it come on sooner, but I keep overshooting the band and either being too low, or too high for the set point.

The lowest this unit is suppose to be capable of being set to -200 (at the lowest), but the ORP on my unit reads (and turns on) well below that when the dial is set to -200 for the set point. I wonder which is correct, the dial or the probe reading?

Dennis

sounds like you're getting there..... mine is set at -155, but it goes close to -200 before it starts back to -155, running at a full stream, pump on. when controller turns off pump it will go as high as -100, still dripping a little, pump off. don't worry to much about ORP set point, ime, anything over -125 gives no3 free effluent with salifert test kit. it will still be a while before you can really crank up the effluent rate, maybe a month, and the input level will need to be low. if your dt no3 is very high the filter will need a lot of dwell time to produce no3 free effluent. i use an Aqua Medic controller, can't advise on yours, but any controller is fine. i used a "rigged" Pinpoint controller and it was fine.

controller:
[URL=http://s1294.photobucket.com/user/CHSUB/media/imagejpg2_zps3e97f455.jpg.html][/URL]

reactor:

[URL=http://s1294.photobucket.com/user/CHSUB/media/imagejpg1_zpsb396951e.jpg.html][/URL]

 

[dartier]

Thanks for the run down on what to expect. I think I am headed in the right direction.

One question I have is, how long between on/off cycles are you getting with your reactor? Mine is coming on at -193 and then it takes 2 minutes and 43 seconds to get up to -173, where it toggles the pump off at. The pump stays off for 6 minutes and then the cycle repeats. The on/off cycle seems short than I was expecting. Perhaps it is because of the smaller size of my reactor? Should I be trying to slow the speed it raises the ORP by slowing the feed flow even more? I have a 1/4" Murlok valve on hand incase I needed a slower feed rate than the lowest setting of DC2000 is capable of.

I am seeing 2.0 ppm of nitrite in the effluent as of tonight.

Dennis

 

[CHSUB]

Thanks for the run down on what to expect. I think I am headed in the right direction.

One question I have is, how long between on/off cycles are you getting with your reactor? Mine is coming on at -193 and then it takes 2 minutes and 43 seconds to get up to -173, where it toggles the pump off at. The pump stays off for 6 minutes and then the cycle repeats. The on/off cycle seems short than I was expecting. Perhaps it is because of the smaller size of my reactor? Should I be trying to slow the speed it raises the ORP by slowing the feed flow even more? I have a 1/4" Murlok valve on hand incase I needed a slower feed rate than the lowest setting of DC2000 is capable of.

I am seeing 2.0 ppm of nitrite in the effluent as of tonight.

Dennis

that's funny!!! i would time my on/off cycles all the time, hoping for improvement, and with so few people running Sulfur this way it's hard to find feed back. Cycle time is also largely effected by flow, however i had very similar times in the early stages of setup. i was using a dosing pump that maxed out at 18 gals per day. After about 10 months it was on nearly all the time and broke. Now i use a small Eheim pump with stronger flow. i would leave the flow as is and let the reactor age. i'm going on 18 months and the reactor is doing perfect!

regarding nitrite, you should be seeing 0.0 very soon, iirc no2 was only readable for a day or two.

 

[Belgian Anthias]

I am not sure I understand your question about regulating the flow. The circulation pump's flow (DC1200) can be adjusted with its controller. This pump runs 24x7. The feed pump (DC2000) also has a controller that can be used to regulate the flow. On its lowest setting, and with the 3/4" output being restricted to 1/4" line, the flow is a slow steady stream.

It means that the pumps are used as riding a bicycle with the brakes on. They will use a lot of power due to the resistance and worn out before the normal lifetime. When the pumps are in a closed loop the flow is easely regulated wile the pumps keep turnig with minimal resistance at normal rate.
As I understand the ORP controller switches the seed pump on and of. With 50 ppm nitrate in the water this may work. Any idea of your daily nitrate production? What when de level descent to for example 5ppm and the flow is restricted by ORP and the oxygen level. One can only remove the quantity of nitrate that passes true the reactor. How much nitrate this system will be able to remove at a level of 1ppm? Will it depend on the nitrate level, the flow or the ORP limits set? Will the system be able to remove the daily production every day and keep the level at 1ppm?

The desire to add carbon was simply to help use up the remaining O2 and get the ORP down to see if the system can hold the ORP down, or if I do in fact have an air leak somewhere causing air to be sucked into the system.

Why not let autotrofe bacteria use up the oxygen? They are responsible for nitrification and are supposed to be responsible for de-nitrification. That is why sulphur is used. No need for organic carbon. Some of these bacteria are able to use up oxygen and switch over to oxidising sulphur. A sulphur denitrator does not have to be oxygen free to function. It works within 24 hrs. This eliminates the risk for anoxic conditions. Most ORP controlled reactors can only reduce a limited amount of nitrate due to the limited flow which makes it impossible to maintain a steady low nitrate level even at very low nitrate productions. A sulphur denitrator should NOT be managed the same way a carbon driven heterothrophe reactor is managed.

When I woke up this morning the DC1200 was again sucking air and I had to manually enable the feed pump to purge the air pocket. Upon doing that the ORP dropped to 18 from 70, and is still dropping as I write this. This might just be the result of insufficient purging of the internal air upon startup. Maybe I did not let the feed pump run long enough before allowing the controller to take over?

May be.

The ORP is controlled not monitored. Though I do stand there starring at the controller more often the I should . There is 50 PPM of nitrate for the system to work on.

At start up phase ( first 2 weeks) I would manage the flow manually; If I had ORP reading I only would use it for monitoring.


The Matrix was an idea that I gleaned from reading the threads on sulfur denitrators (including this one). The premise is that the bacteria can use the Matrix media as place to grow, and still use the sulfur as their food source. In any case, I will most likely remove it and use the space for more sulfur media, just because the reactor is on the small side already.

When a moving bed reactor is used the particles move around with the bio-film on them. When the circumstances are suitable the bio-film on the matrix will not be able to oxidise sulphur limiting the possibilities of the reactor.


I am adding the more tank water every day to the test barrel during my water change to try to get the water level as high as my sump (just incase the there is a leak lower than my normal sump level). One more day and I should have 10" of water in the 29Gal test barrel.

Update: ORP now at 11

When adding fresh system water daily you will not be able to follow the process. Why not fill it up? In- and outflow in the barrel.The nitrate level in the barrel should decrease now and nitrite increase. This will continue till most of the nitrate is reduced to nitrite. After 8 to 10 days nitrite will decrease fast. When nitrite is descending fast during two days your reactor is cured and ready.

Dennis

As far as I know ORP controlled reactors are not able to control the nitrate level and keep it steady. The flow is limited by set ORP limits which in my opinion are mostly set to low. Switching the seed pump on -off may increase the HRT in a way no nitrate is available any more in the reactor inducing unwanted reactions increasing the risk for a failing reactor.

Why ORP control? To keep the reactor in a save working range? As a sulphur reactor will function at positive ORP readings there is no danger for anoxic conditions when clogging is avoided. My opinion ORP control limits the use and possibilities of a sulphur reactor considerably and is not needed at all.
A sulphur driven reactor must not be managed the same way a carbon driven reactor can be managed because all the advantages of a sulphur based reactor will be lost.
ORP control increases the costs of a sulphur based de-nitration system considerably, makes it a lot less affective , limits the possibilities of the system and is certainly not necessary. But that is just my opinion.

A BADESS system will still work at a daily flow of 2x the total aquarium systems volume or more when the reactor is big enough and able to keep very low nitrate levels at daily productions of 1ppm and more. BADESS is PH monitored and can be ORP monitored. Corrections of flow are easily made by hand only when needed.

I wish you a lot of success and I will certainly follow this thread.
As I am against the use of ORP control for the reasons I mentioned and my opinion is made about the use of ORP for the time being I can only wait for someone who proves and shows me otherwise.

 

[dartier]

that's funny!!! i would time my on/off cycles all the time, hoping for improvement, and with so few people running Sulfur this way it's hard to find feed back. Cycle time is also largely effected by flow, however i had very similar times in the early stages of setup. i was using a dosing pump that maxed out at 18 gals per day. After about 10 months it was on nearly all the time and broke. Now i use a small Eheim pump with stronger flow. i would leave the flow as is and let the reactor age. i'm going on 18 months and the reactor is doing perfect!

regarding nitrite, you should be seeing 0.0 very soon, iirc no2 was only readable for a day or two.

Thanks CHSUB. Your posts about using ORP as a means of regulating the sulfur denitrator were what caused me to investigate using a controller rather than trying to adjust and monitor the drip rate.

It means that the pumps are used as riding a bicycle with the brakes on. They will use a lot of power due to the resistance and worn out before the normal lifetime. When the pumps are in a closed loop the flow is easely regulated wile the pumps keep turnig with minimal resistance at normal rate.

I am under the impression that you believe that the circulation pump's flow (closed loop) is being restricted in my system. I am not restricting it at all. I am relying on the DC control features of the pump to regulate the flow.

As I understand the ORP controller switches the seed pump on and of. With 50 ppm nitrate in the water this may work. Any idea of your daily nitrate production? What when de level descent to for example 5ppm and the flow is restricted by ORP and the oxygen level. One can only remove the quantity of nitrate that passes true the reactor. How much nitrate this system will be able to remove at a level of 1ppm? Will it depend on the nitrate level, the flow or the ORP limits set? Will the system be able to remove the daily production every day and keep the level at 1ppm?

As the nitrate level decreases, the amount of water flowing through the reactor will increase. The feedback loop here is that NO3 & NO2 are oxidizer's and raise the ORP level. As the NO3 decreases and the oxidation potential of the water entering is lower (due to less NO3), more flow will be required to maintain the target ORP level, not less water. Eventually at very low NO3 levels, the oxidation potential of the Oxygen in the water will have a far greater impact on the ORP than the NO3. This is really no different than what occurs with non-ORP controlled drip based system. Except the ORP controlled version has the ability to regulate its own operation to a point. At least that is the premise I am going on. Time will tell

When adding fresh system water daily you will not be able to follow the process. Why not fill it up? In- and outflow in the barrel.The nitrate level in the barrel should decrease now and nitrite increase. This will continue till most of the nitrate is reduced to nitrite. After 8 to 10 days nitrite will decrease fast. When nitrite is descending fast during two days your reactor is cured and ready.

The system's inflow and outflow are both within my test barrel (offline from the tank). I was just limited on the amount of test water available since I was using my AWC drain to fill the barrel. As of this morning, the barrel is now filled to level the system would experience in my sump.

As far as I know ORP controlled reactors are not able to control the nitrate level and keep it steady. The flow is limited by set ORP limits which in my opinion are mostly set to low. Switching the seed pump on -off may increase the HRT in a way no nitrate is available any more in the reactor inducing unwanted reactions increasing the risk for a failing reactor.

Why ORP control? To keep the reactor in a save working range? As a sulphur reactor will function at positive ORP readings there is no danger for anoxic conditions when clogging is avoided. My opinion ORP control limits the use and possibilities of a sulphur reactor considerably and is not needed at all.
A sulphur driven reactor must not be managed the same way a carbon driven reactor can be managed because all the advantages of a sulphur based reactor will be lost.
ORP control increases the costs of a sulphur based de-nitration system considerably, makes it a lot less affective , limits the possibilities of the system and is certainly not necessary. But that is just my opinion.

A BADESS system will still work at a daily flow of 2x the total aquarium systems volume or more when the reactor is big enough and able to keep very low nitrate levels at daily productions of 1ppm and more. BADESS is PH monitored and can be ORP monitored. Corrections of flow are easily made by hand only when needed.

I wish you a lot of success and I will certainly follow this thread.
As I am against the use of ORP control for the reasons I mentioned and my opinion is made about the use of ORP for the time being I can only wait for someone who proves and shows me otherwise.

Thanks for the encouragement. Hopefully this ends of being a case of TIMTOWTDI (There Is More Than One Way To Do It).

Dennis

 

[CHSUB]

Thanks CHSUB. Your posts about using ORP as a means of regulating the sulfur denitrator were what caused me to investigate using a controller rather than trying to adjust and monitor the drip rate.




Dennis

THANKS,

hopefully you will have the same results as me. i'm very happy with how the reactor is proforming!

 

[Belgian Anthias]

Thanks for the encouragement. Hopefully this ends of being a case of TIMTOWTDI (There Is More Than One Way To Do It).

Dennis

As the pumps are controlled by there controller the minimum flow is rated 900l/h for the seed pump and 400l/h for the circulation pump. Correct?

As the seed pump is switched on and off there is no continuous supply of nitrate and oxygen. As the HRT is unknown and can not be determined we need ORP to know how long the pump may stay OFF. When the pump stays OFF to long oxygen and nitrate may be used up. ORP is used to switch ON the pump to avoid anoxic conditions. So this ORP regulated system makes itself necessary for avoiding problems which are created by the system itself. When we remove it, we do not need it any more? We need it because we installed it. This is not the high tech solution I am waiting fore !?
But I agree.TIMTOWTDI

Do you think that a ORP controlled reactor will increase the flow in accordance with the nitrate level? Now the system contains 50ppm. How much the flow will be increased when 1ppm will be reached?

To remove 1 ppm daily out of a 120 gal system at 50ppm only 2.4 Gal / 9.2l of water has to pass the reactor daily when the effluent is 0. That is dripping rate.
To remove 1 ppm at a daily basis with 2 ppm in the water a daily flow of 1/2 the systems volume is needed, in your case 60 gal/day. This is more than dripping rate.
At a nitrate level of 1ppm the flow must be the double to remove the same daily production of 1ppm which is 120Gal/day. At 0.5ppm 240 gal/day. How this can be managed by a ORP controlled reactor. Each liter of water contains at least 6x more free oxygen than nitrate at that moment. When flow is increased how ORP will respond?
In a drip rated reactor the free oxygen reducing army is very limited. When flow is increased the army needs time to grow to remove this oxygen so ORP will increase. How much the flow can increase while the ORP reading must stay within low negative limits? Will the flow increase or decrease?
At dripping rate the total system water needs 10 days ore more to pass true the reactor and only very small amounts of nitrate can be removed daily at low nitrate levels which means that when the level can be kept steady this way you do not need a sulphur denitrator.
A sulfur denitrator works fine and is self regulating when there is enough daily nitrate production.
We mange our reactors differently and keep high flow with a very active oxygen reducing army because this army has a lot more work to do than the nitrate reducing army. Some will go from one army to the other. To lower the level we only have to adjust the flow till more than the daily production is removed. Once the desired level is reached and the reactor is stabilized it will be self-regulating within its limits. Corrections are only needed when nitrate production changes considerably . The level may be kept steady at a low nitrate level as desired and still remove high daily nitrate productions ( when the reactor is big enough)
ORP can help in monitoring the system.
ORP control of the flow limits the working range of the sulphur reactor considerably and makes it impossible to mange the nitrate level in the aquarium system because nitrate removal is limited and not predictable .

 

[CHSUB]

Do you think that a ORP controlled reactor will increase the flow in accordance with the nitrate level?

YIKES!!!!!!!!!!!∞

that is what is does....higher NO3 longer off time, lower NO3 shorter off time. this has been discussed over and over......

 

[dartier]

As the pumps are controlled by there controller the minimum flow is rated 900l/h for the seed pump and 400l/h for the circulation pump. Correct?

Correct. Though I am thinking about getting another DC1200 for the feed pump instead of the DC2000

As the seed pump is switched on and off there is no continuous supply of nitrate and oxygen. As the HRT is unknown and can not be determined we need ORP to know how long the pump may stay OFF. When the pump stays OFF to long oxygen and nitrate may be used up. ORP is used to switch ON the pump to avoid anoxic conditions. So this ORP regulated system makes itself necessary for avoiding problems which are created by the system itself. When we remove it, we do not need it any more? We need it because we installed it. This is not the high tech solution I am waiting fore !?
But I agree.TIMTOWTDI

Do you think that a ORP controlled reactor will increase the flow in accordance with the nitrate level? Now the system contains 50ppm. How much the flow will be increased when 1ppm will be reached?

That is the million dollar question. However I only plan to control the Nitrate, not remove all of it. My expectation is that at lower levels of Nitrate, I will want to adjust my target ORP setting on my controller to limit the amount of time the feed pump runs for to avoid extra sulfate from being added.

To remove 1 ppm daily out of a 120 gal system at 50ppm only 2.4 Gal / 9.2l of water has to pass the reactor daily when the effluent is 0. That is dripping rate.
To remove 1 ppm at a daily basis with 2 ppm in the water a daily flow of 1/2 the systems volume is needed, in your case 60 gal/day. This is more than dripping rate.
At a nitrate level of 1ppm the flow must be the double to remove the same daily production of 1ppm which is 120Gal/day. At 0.5ppm 240 gal/day. How this can be managed by a ORP controlled reactor. Each liter of water contains at least 6x more free oxygen than nitrate at that moment. When flow is increased how ORP will respond?
In a drip rated reactor the free oxygen reducing army is very limited. When flow is increased the army needs time to grow to remove this oxygen so ORP will increase. How much the flow can increase while the ORP reading must stay within low negative limits? Will the flow increase or decrease?
At dripping rate the total system water needs 10 days ore more to pass true the reactor and only very small amounts of nitrate can be removed daily at low nitrate levels which means that when the level can be kept steady this way you do not need a sulphur denitrator.
A sulfur denitrator works fine and is self regulating when there is enough daily nitrate production.
We mange our reactors differently and keep high flow with a very active oxygen reducing army because this army has a lot more work to do than the nitrate reducing army. Some will go from one army to the other. To lower the level we only have to adjust the flow till more than the daily production is removed. Once the desired level is reached and the reactor is stabilized it will be self-regulating within its limits. Corrections are only needed when nitrate production changes considerably . The level may be kept steady at a low nitrate level as desired and still remove high daily nitrate productions ( when the reactor is big enough)
ORP can help in monitoring the system.
ORP control of the flow limits the working range of the sulphur reactor considerably and makes it impossible to mange the nitrate level in the aquarium system because nitrate removal is limited and not predictable .

Once I have the nitrate under control and no longer accumulating, then I need to tackle phosphate. Though not in the way you would assume. My Phosphates are not too high, they are non-existent. In fact they are so non-existent that I have to dose Seachem flourish with a dosing pump on a continuous basis or my corals STN/RTN.

The phosphate issue is a problem of my own design unfortunately. I run All-In-One Biopellets, and for some reason on my system, they are far more effective at removing phosphates than nitrate. Currently I have a DIY recirculating reactor being fed off a manifold, but I am fed up with trying to get the flow right using a ball valve. My plan is to put a feed pump on the reactor timed by my aquarium controller so that I can adjust the amount of water flowing through the reactor electronically. If I could use a probe to control this reactor as well, I would

Setting drip rates and then having to monitor them for slowing down and clogging/stopping is not for me. Down that road lies madness :rollface:

Dennis

 

[CHSUB]

Do you think that a ORP controlled reactor will increase the flow in accordance with the nitrate level? Now the system contains 50ppm. How much the flow will be increased when 1ppm will be reached?

That is the million dollar question.

I agree, "œThe million dollar question"? Maximum vs. equilibrium, as I stated early imo, it's closer to max. I did however take Mr. Belgium advice to task. When my dosing pump failed, I connected the reactor to my manifold and ran a constant flow and a higher ORP (-50 to 0) while testing the effluent. I found ORP above -100, -99,-98 etc. give a slight pink on a Salifert Tester, which imo is unacceptable. I would slow flow some, test until Salifert was clear (ORP~ -150) and try to increase flow again. I would, however, never get greater flow than I would with ORP controlling the pump. I also feel a test kit with greater accuracy would be needed to properly tune a reactor without ORP, as the NSW that I get from Halover Cut in Miami always shows clear on Salifert and I'm sure no3 is present. Imo, the reactor performs best from -150 to -190 ORP, which gives unreadable NO3 and good flow.

 

[dartier]

Hey CHSUB, how are you mounting your ORP probe? I am using the Avast thread insert that came with my Kalk reactor, but I just figured out that the back pressure from the sulfur prills are causing a steady leak out of the ORP probe insert. Just curious what you are using, or if you have any suggestions. I am surprised there is no o-ring on these Avast probe inserts?

Dennis

 

[CHSUB]

Hey CHSUB, how are you mounting your ORP probe? I am using the Avast thread insert that came with my Kalk reactor, but I just figured out that the back pressure from the sulfur prills are causing a steady leak out of the ORP probe insert. Just curious what you are using, or if you have any suggestions. I am surprised there is no o-ring on these Avast probe inserts?

Dennis

my reactor has a built in port in the reactor body. if you look at the top right of my reactor pic you can see the probe and wire. i would think the Avast would be water tight? i looked at some ports when i was thinking of building a larger reactor and couldn't imagine they would leak?

 

[Belgian Anthias]

Do you think that a ORP controlled reactor will increase the flow in accordance with the nitrate level?

YIKES!!!!!!!!!!!∞

that is what is does....higher NO3 longer off time, lower NO3 shorter off time. this has been discussed over and over......

So, when the nitrate level drops from 2ppm to 1ppm the flow will be doubled,? Because that is what it has to do to remove the same daily production and keep the level steady. I do not think so. When the flow is increased more free oxygen is entered ( 3x more than at 2ppm nitrate, 6 x more at a nitrate level of 1ppm) As a ORP controled reactor has a very small oxygen consuming army( very low flow) when flow increases it can not follow and free oxygen will increase fast. ORP will rise above limits. What will the flow do when ORP controled? I think that the flow will decrease again to keep the reactor within ORP limits. Here the flow is not decreased but interrupted. One moment there is oxygen to remove and a moment later there is non to remove.

i am sure ORP control can be used to keep the reactor anaerobic!
The question is WHY?
What is the main purpose for using ORP? To prevent anoxic conditions?
When no ORP control is used there is no risk for anoxic conditions. A Sulphur denitrator must not be kept anaerobic! Only a small part is enough! No risk!
it is proven that a sulphur denitrator will still remove some nitrate at a flow of 10x its own volume and starts to work when the oxygen level descents below 3ppm.
ORP monitoring? Yes, why not.
ORP control? Why? I can only see disadvantages.