Successful RO cleaning done 👍

[Baldmonkey]

I can confirm (following on from a previous post) that i have successfully cleaned/reset/renewed my ro membrane.

1. Ro was very clogged up and waste was running very slow in comparison to the pure and pressure.
To get an equal rejection rate of 50/50 i had to lower my pressure down to 70 psi from the normal operating pressure of 100 psi.
Im running a spectrum membrane from doug @ daqua (im sure thats what it is, might be wrong)
When new i was getting roughly 98% rejection rate and the membrane has always performed well.
I have 2 x 10 inch 1 micron sediment filyers followed by 3 x 20 inch charcoal filters, always changed regular etc.
Before cleaning i was getting 89% rejection rate but with very restricted waste flow and poor production litres per min.

2. I used hydrex 4502 and hydrex 4503. A high ph and low ph cleaner, others are probably available,l and i was given these so no idea how much they cost.
Circulated a 1/35 mix of both, not at the same time, through my booster pump which was feed from my drainage sink and the pure and waste from the ro, left that circulation for am hour each.
Ran a flush from mains water after reconnecting for approx 30 mins. Set the system going and was nack up to 98% rejection rate, flow was around 55 waste 45 pure @100psi with a good production rate too.
after doing the calculation of what my 4040 held along with pipes and circulation resevoir, i only ended up using approx 300ml of each chemical.
Personally i will now always clean my membrane and save on replacement costs unless absolutely necessary

 

[Pjj]

I can confirm (following on from a previous post) that i have successfully cleaned/reset/renewed my ro membrane.

1. Ro was very clogged up and waste was running very slow in comparison to the pure and pressure.
To get an equal rejection rate of 50/50 i had to lower my pressure down to 70 psi from the normal operating pressure of 100 psi.
Im running a spectrum membrane from doug @ daqua (im sure thats what it is, might be wrong)
When new i was getting roughly 98% rejection rate and the membrane has always performed well.
I have 2 x 10 inch 1 micron sediment filyers followed by 3 x 20 inch charcoal filters, always changed regular etc.
Before cleaning i was getting 89% rejection rate but with very restricted waste flow and poor production litres per min.

2. I used hydrex 4502 and hydrex 4503. A high ph and low ph cleaner, others are probably available,l and i was given these so no idea how much they cost.
Circulated a 1/35 mix of both, not at the same time, through my booster pump which was feed from my drainage sink and the pure and waste from the ro, left that circulation for am hour each.
Ran a flush from mains water after reconnecting for approx 30 mins. Set the system going and was nack up to 98% rejection rate, flow was around 55 waste 45 pure @100psi with a good production rate too.
after doing the calculation of what my 4040 held along with pipes and circulation resevoir, i only ended up using approx 300ml of each chemical.
Personally i will now always clean my membrane and save on replacement costs unless absolutely necessary

This is very interesting we need more of this type of information on the forum , it will be interesting to see how long this clean lasts , what are you expecting and how did you get this information and chemicals ?

 

[Baldmonkey]

This is very interesting we need more of this type of information on the forum , it will be interesting to see how long this clean lasts , what are you expecting and how did you get this information and chemicals ?

Hi paul
I first thought there must be a way to clean the membranes years ago, but after a google search turned out to be a chemical minefield i forgot about it.

Anyway, ever since i was a kid, if something broke i opened it up to see what was inside, how it worked and possible see if i could fix it. Whwn i replaced my last membrane, i cut the old one open to have a look.
It was green and gunged up inside, the membrane itself was made out of good solid materials and saw no reason why this couldnt be cleaned, after all thats what we do for a living

Thought nothing more and carried on with the new membrane, fast forward to about 3 months ago and i saw a 20ltr container outside a customers house that said "membrane cleaner" on the label....

Had a full on conversation with him next time i saw him and it turns out he was in water treatment cleaning facilities and proceeded to tell me he had never come across an ro membrane that was uncleanable and outright disposable.

He said the performance deteriorates but can be sorted with a clean.

Sorted me out with a litre of each chem and bobs your uncle

 

[Baldmonkey]

This is very interesting we need more of this type of information on the forum , it will be interesting to see how long this clean lasts , what are you expecting and how did you get this information and chemicals ?

Im expecting the membrane to be virtually reset in terms of performance, longevity will be deyermined on the method i used and the chemicals themselves, but barring any deterioration of the membrane itself, i dont see why it cant be done each year for the foreseeable... Time will tell i guess

 

[Pjj]

Im expecting the membrane to be virtually reset in terms of performance, longevity will be deyermined on the method i used and the chemicals themselves, but barring any deterioration of the membrane itself, i dont see why it cant be done each year for the foreseeable... Time will tell i guess

Keep us informed how this goes , I recently replace two membranes and also cut one up as was interested to see what it was like mine had a brown discolouration on what looked like paper wound into a cylinder, but apart from that looked ok , didn’t have any issues with slow or low flow but efficiency was down . Very interesting post we need more of this type of thing