Question on after RO use rinse

[mol1jb]

Ok so after the RO runs out of sap I am initially rinsing the membrane for 3-4 minutes to remove residual sugar and sending this to the concentrate tank. After that then the full rinse. My question is with the what to do with any remaining liquid in the concentrate line that goes to the concentrate tank? Is the sugar level low enough after the 3-4 minute rinse to let it be till the next RO use? How much % sugar would be in there after such a rinse?

[Dennis H.]

For me I normally will check the liquid going to the concentrate to see the sugar content drop while pushing the remaining sweet out of the RO.
For me this is about 1%, once I hit that I throw the valves and send it to drain for a few moments.
Now I will do a True rinse and then if necessary a wash.

I would not hold it till next time unless that next time is really soon, the sweeter the sap the faster it will start to go bad, and you do not want to add a little sap to a nice big load of fresh sap.

[needmoremaples]

the chance of someone answering that and you testing it and getting the same result isn't good. you need a sap hydrometer and figure out your own conclusions. when i start tapering off in sugar % put some into a bucket to go back into the regular sap tank. the rest of the rinse water goes on the ground after the sugar is nil.

[Russell Lampron]

I check the sugar in my concentrate with a refractometer and when it gets down to less than .5% I consider the sugar flush done. It sometimes takes up to 10 minutes to get all of the sugar out. I let it flush for 5 minutes before I even start checking the sugar. I have my plumbing set up so that I can drain pipe from the head tank back into the RO room when I'm done with the flush. There isn't much sugar in it at that point so I just run that into the drain. I then do a soap wash and then a rinse.

[butler]

How long does soap rinse take?

[Russell Lampron]

How long does soap rinse take?

It depends on if you heat the wash water or let your RO heat it. On mine I've never timed it but it takes 2 or 3 hours. My RO will slowly heat the water as it is pumped through. Some RO's won't heat the water and you will need to heat it yourself. When it's up to temperature it doesn't take very long.