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seldon
06/02/2015, 07:47 PM
I recently purchased a used CSPDI-90. I have been testing the performance and have some questions about the results which are below.

Test results were determined by flushing the membrane for 30 min then running it with a 550 ml cylinder style flow restrictor for 15 minutes before measuring the below values.

Hardness: 50 ppm
Pressure on Membrane: 54 psi
Temperature: 64F
Expected GPD: 65.124

Incoming TDS: 139
Good Water TDS: 3
Membrane Efficiency: 97.8%

Brine flow in 60 seconds: 505 ml
Good water in 60 seconds: 110 ml
Membrane Performance Ratio: 4.59:1

In a nut shell, I would expect to see a higher product amount of about 171 ml/min. Any help would be greatly appreciated.

Thank you.

alan jeffery
06/03/2015, 05:47 AM
Water temp and psi will affect the RO output

SpectraPure
06/03/2015, 09:36 AM
What is the previous history of this system? How old is it? How hard was the tap water?

Since you have replaced the original flow restrictor with someone else's, what was the waste to product ratio with the original flow restrictor? Why did you replace it?

Not knowing the answers to these questions puts us in the dark as to why the membrane is not producing the expected output.

Support at SpectraPure dot com

seldon
06/03/2015, 02:54 PM
Alan,
Temperature and pressure were taken into consideration. That is where the expected GPD of 65.124 value came from versus the label rate of 90 GPD.
Seldon

SpectraPure
06/03/2015, 03:57 PM
I recently purchased a used CSPDI-90. I have been testing the performance and have some questions about the results which are below.

Test results were determined by flushing the membrane for 30 min then running it with a 550 ml cylinder style flow restrictor for 15 minutes before measuring the below values.

Hardness: 50 ppm
Pressure on Membrane: 54 psi
Temperature: 64F
Expected GPD: 65.124

Incoming TDS: 139
Good Water TDS: 3
Membrane Efficiency: 97.8%

Brine flow in 60 seconds: 505 ml
Good water in 60 seconds: 110 ml
Membrane Performance Ratio: 4.59:1

In a nut shell, I would expect to see a higher product amount of about 171 ml/min. Any help would be greatly appreciated.

Thank you.

The rated gpd is + or - 10% of 90. 54 psi is 10% less of the 60 that we test under. So there is -9 right off the bat. Then water temperature has a huge impact. Nominal is 77. Anything lower starts to decrease the production rate. If you only have 67 degree water temperature, that would be the 81 gpd multiplied by 0.826. which comes out to 66.9. Now we either do the + or minus 10% and we have a range of 60 to 75 gpd.

This is standard for any membranes. I have tested tens of thousands, and I find that your results are common industry wide. A booster pump to increase your psi to about 75 will make a huge difference on water production, and DI longevity.

Jeremy

seldon
06/03/2015, 04:17 PM
The rated gpd is + or - 10% of 90. 54 psi is 10% less of the 60 that we test under. So there is -9 right off the bat. Then water temperature has a huge impact. Nominal is 77. Anything lower starts to decrease the production rate. If you only have 67 degree water temperature, that would be the 81 gpd multiplied by 0.826. which comes out to 66.9. Now we either do the + or minus 10% and we have a range of 60 to 75 gpd.

This is standard for any membranes. I have tested tens of thousands, and I find that your results are common industry wide. A booster pump to increase your psi to about 75 will make a huge difference on water production, and DI longevity.

Jeremy

Jeremy,

I should have been more clear in my original post. I completly agree with your math. I calculated 65.124 as what I should see in my original post that you quoted. However, I am only seeing 41.84 GPD (I extrapolated this from the 110 ml/min that I measured) which is 35.75% less than my expected value of 65.124 GPD and is where my questions are coming from.

To answer the other spectrapure persons questions, I unfortunatly do not have the past history as I am I believe the 3rd owner now. I purchased the unit off this forum. The date on the membrane housing is 7-2012 and if that is the production date,t he unit is just shy of 3 years old.

The tap water hardness is approximately 50 ppm whis is about 3 GH so the water is soft.

The flow restrictor is what was on it when I bought it and as such I cannot speak to any other waste to product ratio other than what I have posted above.

I do have some 1/4" ball valves I can use to throttle the waste water back to a set flow for you if that will help show anything.

I have checked the pressure drop across the sediment and carbon filters and it is only at 4 psi so it appears that they are ok.

Are there any other tests I can do for you to help trouble shoot. I am just trying to determine what I need to purchase to get this used unit up to speed.

Jeremy,

My plan is to purchase a booster pump and potentially a piggy back kit downt he road. Also due to my low incoming TDS and low GH I would like to look at getting this unit to a 2:1 waste to product ratio.

Thank you,

Seldon

SpectraPure
06/04/2015, 09:44 AM
Seldon, and others following

The cylindrical flow restrictors have a screen in them that clog up with calcium bicarbonate, or another form of bicarbonate. Any membrane can handle a low waste, but the production of a membrane will drop off if the waste is not enough. Now a standard 90gpd will do around 220-250 ml/min on the product water side in a minute under the test criteria that was stated. 550ml cylindrical flow restrictor is rated at 50 psi, and not the 60 Psi that Spectrapure uses. So what happens to membranes that do not have adequate waste water. Well they slow down over a period of time to as little as 40ml/min on the product water side.

Also in order to have a 2:1 waste ratio we need to determine with a General Hardness Test Kit what our hardness is. Perhaps it is 40. Sometimes people mistake general hardness for Total Dissolved Solids. A flush valve is also critical in the 2:1 waste ratio. That valve that you refer to tweak the waste is the flush valve. We open this valve to flush the stagnate water out of the membrane for 45 seconds before making water and then we close the valve to make our water. Then when we are finished making water we open the valve again for another 45 seconds to flush out the membrane again to filter out any unprocessed water that is still in the membrane. We then turn off the water source until we need to make water again. I leave my flush valve open at all time, unless im making water. This way it sets a reminder for me to flush the system.

Now the booster pump will help, however someone clearly put a competitor flush valve on this system which was a huge mistake. The capillary flow restrictors that we use do not allow for clogging of the waste water over time. A new membrane and flow restrictor will net you about 200 ml/min at your location now that it is summerish for you. A booster pump will do wonders not only for your membranes production performance, but it will also extend the life of your DI cartridges. The membrane produces much more efficiently on both aspects of production and rejection at higher flows. However you cannot exceed 75 psi due to the pressure rating on most clear housings. If this worries you we have commercial grade housing that are much better.

Email me your contact information so we can talk a little bit over the phone. I will get you set up at a discounted price. Anyone one this thread is implored to sell Spectrapure competitor's stuff, and I will give you a generous discount on Spectrapure products. We are a complete water purification company that handles all aspects of water purification. We are solely based on research and development through scientific studies. Please send a picture of your system and contact info to. When we consumers for whatever products we purchase understand that there is much more value given with some than others when making a purchase. I hope to spread that to everyone when making a purchasing decision. Check out our Facebook page!


support@spectrapure.com

Jeremy

seldon
06/05/2015, 09:10 AM
Email sent.

seldon
06/05/2015, 09:08 PM
Jeremy,

I have access to a lab at work that does water testing. As such, I had them test my water to confirm my tests at home. The results are as follows:

General Hardness: 60 ppm (~3.4 dGH)
pH: 9.06
Total Chlorine: 1.8 mg/L
Free Chlorine: 0.12 mg/L
Silica: 4.4 mg/L

Seldon

swk
06/06/2015, 01:17 PM
Seldon, and others following





Email me your contact information so we can talk a little bit over the phone. I will get you set up at a discounted price. Anyone one this thread is implored to sell Spectrapure competitor's stuff, and I will give you a generous discount on Spectrapure products. We are a complete water purification company that handles all aspects of water purification. We are solely based on research and development through scientific studies. Please send a picture of your system and contact info to. When we consumers for whatever products we purchase understand that there is much more value given with some than others when making a purchase. I hope to spread that to everyone when making a purchasing decision. Check out our Facebook page!





support@spectrapure.com



Jeremy


You guys are the best in the business ime. The customer service and way you stand behind your products is second to none. Awesome to see and will keep me buying your products without shopping around, no question. Keep it up!

SpectraPure
06/08/2015, 09:03 AM
You guys are the best in the business ime. The customer service and way you stand behind your products is second to none. Awesome to see and will keep me buying your products without shopping around, no question. Keep it up!

Wow. Thanks a lot!!!! You just made my day!

Jeremy

swk
06/08/2015, 09:58 AM
Wow. Thanks a lot!!!! You just made my day!



Jeremy


No need to thank me Jeremy. I don't spout off like a fanboy hardly ever, but the company, and you in particular have earned it. I hope they take good care of you. And yes, you may show the higher ups this post ;-)

Hell, if you guys sold groceries I would shop there for those too.

FYI - ever since I replaced the rollers and tubing in the lm3 slave pump it has been smooth sailing without any random "all pumps off" screens.

SpectraPure
06/08/2015, 01:03 PM
Also-
I checked with our chemist, and he mentioned your mono chloramines sound high from your numbers, and he would recommend using a good catalytic carbon filter as well to enhance your longevity/performance.

We sell one:
http://spectrapure.com/FILTERS-MEMBRANES-RESIN/CARBON-FILTER-CARTRIDGES/1-Micron-ChlorPlus-Chloramine-Removal-Carbon-Block-Filter-10-inch

Also, your membrane could be biologically fouled or hardened (is the outside of the membrane slimy or crystalline?) which would give the production issue you are seeing. The rejection you have is pretty good actually. I would pull it out and look at it.

Another thought is it may have been replaced with a smaller membrane.

Lets look at fouling next, or possibly a calcified membrane (if it was run in hard water previously).
Hope this helps
bruce


.

SpectraPure
06/08/2015, 04:18 PM
No need to thank me Jeremy. I don't spout off like a fanboy hardly ever, but the company, and you in particular have earned it. I hope they take good care of you. And yes, you may show the higher ups this post ;-)

Hell, if you guys sold groceries I would shop there for those too.

FYI - ever since I replaced the rollers and tubing in the lm3 slave pump it has been smooth sailing without any random "all pumps off" screens.

Again I am blown away by your kind words. I stand here humble. Please let me know if you every need help on anything at all.

Jeremy

seldon
06/09/2015, 07:38 PM
Bruce,

Would I be correct in assuming that the catalytic carbon filter would go between my existing 0.5 micron sediment filter and my 0.5 micron carbon block filter?

Are there any other numbers that I should get that would be helpful? Based on the chemistry numbers that you have, would you think I would be a good candidate for a 2:1 waste ratio? What single or dual DI membrane setup would you recommend?

I am traveling this week so I'll check for calcification and if the membrane is slimy when I get back. As for checking if the membrane was replaced with a smaller one, the thought never crossed my mind so thanks for that.

Thank you for checking on my water chemistry and for suggesting the things to check with the membrane. I really appreciate all your help and support.

Seldon

seldon
06/11/2015, 07:04 PM
Reading through the chloramines sticky, I see you call out putting the catalytic carbon filter between the sediment and block carbon filter.

One question that did raise for me was around my pH, which at 9 would create some other issues with my membrane. I see you recommend adding HCl to lower the pH. I can pick up some muriatic acid and would dilute that with water to get the correct molarity, then would inject that into my water inlet stream. Could you recommend a chemical injector? Doing the math, it doesn't take much to drop the pH. I haven't had much luck finding an injector with a high enough ratio. I was thinking of using a dosing pump to inject it into the water stream. Have you seen this done the way I described? Do you have any suggestions or would it not be worth the trouble?

Seldon

seldon
06/13/2015, 06:05 PM
Also-
I checked with our chemist, and he mentioned your mono chloramines sound high from your numbers, and he would recommend using a good catalytic carbon filter as well to enhance your longevity/performance.

We sell one:
http://spectrapure.com/FILTERS-MEMBRANES-RESIN/CARBON-FILTER-CARTRIDGES/1-Micron-ChlorPlus-Chloramine-Removal-Carbon-Block-Filter-10-inch

Also, your membrane could be biologically fouled or hardened (is the outside of the membrane slimy or crystalline?) which would give the production issue you are seeing. The rejection you have is pretty good actually. I would pull it out and look at it.

Another thought is it may have been replaced with a smaller membrane.

Lets look at fouling next, or possibly a calcified membrane (if it was run in hard water previously).
Hope this helps
bruce


.

Bruce,

I had a chance to check my membrane today. First off, it is a 90 GPD membrane. It was not slimy and did not appear to be calcified. I was unable to read the date on the membrane. I will take some pictures if that will help.

What I did notice however was that it looks like the carbon filter was never flushed prior to install as what seemed like a lot of carbon particulate came out of the housing and the membrane.

Let me know if you think this could be a potential cause.

Seldon

SpectraPure
06/15/2015, 09:24 AM
Sometimes the water companies spike the PH to lower the TDS. What is the KH of your tap water? I see that the PH is kind of high. These are tap water parameters right? What is the TDS of the product water coming out of the system?

Jeremy

seldon
06/15/2015, 06:27 PM
Jeremy,

My Carbonate hardness is 60 ppm or ~3.4 degrees of KH. I agree my pH is high and believe it is a result of how my city softens the water. Yes, the values are from tap water.

The tap water TDS is 139 and the good product water is 3 prior to my DI and 0 after the DI.

Seldon

SpectraPure
06/17/2015, 09:53 AM
Seldon email me your complete contact info for a membrane warranty. Please provide of proof of purchase. Thank you very much for hanging in there. I agree that given your membranes parameters, your knowledge of them, the amount of avenues we looked at, and other variables I have decided to warranty the membrane. =) I appreciate your loyalty to Spectrapure. Thank you very much.

Jeremy

seldon
06/17/2015, 11:05 AM
Jeremy,

I am not the original owner and as such am not looking for a warranty replacement, but just guidance and support (which you have been providing) to determine root cause. I am also looking for guidance on how to further develop my system so that it is better performing (eg. Booster pump, correct flow restrictor, flushing methodology, how to handle my high pH). If you like, I can start another thread to discuss the improvements now that we've identified I need to replace the membrane.

Seldon

SpectraPure
06/18/2015, 04:04 PM
I appreciate your candor.
I would like it if you started a thread on how you improved your rejection performance as the factors you are encountering and moving thru are very common, and not widely understood.
We appreciate you allowing us to help you along on your journey to excellence.
bruce