Looking for an RO/Di master

[johnd651]

lol...so i hope that title was catchy enough. but i was actually wondering

i have two similar ro/di units, that i have put together to work as a 5 stage RO/DI filter.

After working on it yesterday, i have almost everything figured out except:

on the membrane housing where does waste/product water come out of the membrane? what comes out the center of the membrane (white tube)? what comes out through the sides (wrapped around the white tube)?

The unit seems to have a 100gpd membrane, and there is no flow restrictor. I did find one in a hose that was not attached, just in the box, but it seems tiny, like for the 25 or 50gpd units. is a 1/4inch hose restriciting enough for a 100gpd unit? the unit originally was a coralife ro unit, if that helps.

also, after reorganinzing everything, I now have 4 chambers and the ro membrane. What should go in the chambers??? Should I run 3 pre-membrane, and 1 di post-membrane? should i run 2pre and 2 di post?

my thought was a 5micron sediment, 5 micron carbon (or chloroamine, as needed), 1 micron carbon, membrane, di resin.

also, there where a couple of ball valves. do i need them? where should i put them in? i was going to have one on the incoming water, before it goes into the unit, and one on the output of the DI chamber. other then that, is there a reason for these ball valves?

PS---i will post pictures, but it will not be until much later tonight.

 

[xpxdx]

sounds like a fun project

on mine the waste water comes out the side and the product water from the middle. you will definitely need a flow restrictor that is matched to your ro membrane, otherwise it won't work at all. it looks like a cylinder and goes on the waste line.

most units have 3 carbon/sediment filters before the ro membrane, and a di after.

i would look at sites like bulkreefsupply.com and see how their units are put together...

good luck!

 

[superkat]

if i remember correctly..someone out there who's house i went to...had an amazing system...THAT THEY MADE THEMSELVES....that's your master, right there...

 

[StashuDave]

I would copy the Spectrapure MaxCap system personally. 1 micron prefilter, 1 micron carbon, then R/O membrane, then 2 DI cartridges. I would also just use the flow restrictor that you have and then use 1 of the ball valves on the waste water line so that you can fine tune your waste/ product water ratio. Hopefully your R/O membrane housing has a pressure guage... this will allow you to close the waste water as much as possible while maintaining the greatest pressure. I'd obviously put one of the other ball valves on the actual input of the unit for ease of servicing the unit. The only other suggestion would be to get a dual inline TDS meter.... put 1 sensor after the actual R/O output and the other after the 1st DI cartridge. This allows you to monitor whats coming out of the membrane and you can verify that the 1st DI cartridge is bringing the TDS down to 0. As soon as that 1st DI cartridge registers 1 TDS, then you yank it out, move the 2nd DI into the 1st position and put a new DI cartridge in the 2nd position! This system assures that 0 TDS is always achieved...... there are a million different ways to do this based on water pressure and water temperature and your particular water source...... so there's never 1 perfect answer.
Dave

 

[johnd651]

dave, i see where you are going with that. it just makes sense hearing it from someone else

as for the 2 di, most of the 5 stage systems i have seen have only 1 DI. what benefits are there for 2 di, vs 3 pre-membrane filters?

 

[StashuDave]

I really like knowing that whatever comes out as good product water is definately 0 TDS, and using the dual DI in the manner I described assures me of that. As far as 3 prefilters or 2...... I think using a smaller micron cartridge is more important than the number of cartridges. The carbon cartridge is really just used to get rid of chlorine.... smaller micron cartridges are rated for more gallons, ballpark a 1 micron cartridge cleans 10,000 gallons and a 5 micron cleans 3500 gallons..... so by using 1 1micron cartridge, I can clean more water than 2 5micron cartridges. I also really rely on my pressure guage to tell me when to change cartridges. Using 5 micron cartridges....its going to take alot longer for them to clog, even though they should be changed more frequently. I'd rather the cartridge clog up on me before it is really fully exhausted.... this would kill the pressure in my R/O housing and alert me to an issue.... and my first fix for an R/O issue is to put in new prefilter and carbon cartridges. Secondarily the cost of replacing the cartridges usually favors my method.... 1 micron carbons are not that much more than 5 micron ones, so again, why buy 2 when I can buy just 1? Hope I've helped......
Dave

 

[johnd651]

i do see what you are saying. i ended up doing 2 pre membrane, and 2 di. it just fits better. this is what it looks like right now.

i still need to get DI cartridges. (if anyone has extra refillable DI cartridges...let me know)

 

[superkat]

you guys are gonna flip if what I talked about with an engineer friend of mine tonight after the theater really works...it involves an old water softener system we dragged back to NY from California.....

 

[talon4x4]

you guys are gonna flip if what I talked about with an engineer friend of mine tonight after the theater really works...it involves an old water softener system we dragged back to NY from California.....

Sounds interesting, do share. I have a new water softener collecting dust in my garage. Maybe I could put it to use.

 

[StashuDave]

John- Looks good!!!!!
Kat- I'm interested also....... Water softeners seem pretty useful in this area with our hard water, seems to make sense they could help "purify" our water source alot before it even hits our actual R/O unit.

Dave

 

[johnd651]

yes...share...

 

[captain7359]

Here's how I piggybacked my membranes, so I wast less water and double my output. It is a little tougher on the second membrane, but less waste water is more important to me. I have a regular flow restrictor, not the capillary tube they mention.

http://www.spectrapure.com/manuals/PRINTER_FRIENDLY/PBK.pdf

Here's my wall of filters

The bottom 3 on the left are beer water filters and aren't tied into the fish ro/di. I do sediment, carbon, carbon block, dual ro, then into 2 di canisters with color change media. It usually pumps out 50-60 gallons in 8-10 hours with dual 75gpd membranes. I also have it being fed from before the house pressure regulator so it gets 80-100 psi mwhich helps the waste ratio and gives me better product water.

 

[superkat]

these chambers and all the tubing/equipment we brought with us stand 4ft tall. there are 4 chambers (tanks - not PVC...but sturdy plastic...and pretty attractive, actually.) the water softener system actually uses salt to remove the impurities. one of the chambers is a self contained skimmer with a removable compartment to empty the crud. another is carbon, another is a circulation unit, the final is a fine filtration chamber...7 layers of material (one is sand) that fine filters the water before sending it TO YOUR FAUCETS. So literally...the water in any of the house's faucets are purified. We are going to set this up (which could take some time....and space) and start doing some testing...using materials you would use as filtration in a regular RO/DI unit. When we bought this, it was simply called a Water Softener Unit...however, reading the instruction manual (yeah, i'm OCD, i keep everything...EVERYTHING)....we realized that it is, for all intents and purposes and HUGE RO/DI...it even says so in the instructions. The issue would lie with the plumbing to the faucets since all of ours are copper. But if we set this up in the basement, it would be easy to replace all the plumbing with PVC and the fixtures so that it becomes a viable system. The end result would be auto top off from the sink utilizing a drip valve. For the other tanks...simply filling up a bucket, or running a hose from the sink to the tank. Mixing salt water would be a breeze. So there you have it. I'll keep you posted as we start putting this together. Seriously...this system is a monster...

 

[johnd651]

pictures??? sounds interesting.

where i work we use a similar setup to the fish ro/di for our lab water (just about $4800 more). it just has a holding tank, then di resin and UV. the spout returns half to the tank, so it goes through the Di and uv again.

but the place below us, some DoD machine shop, uses RO/Di water for there coolant mixtures. there system is huge. it consists of a sediment filter, two 4 foot by 1 foot wide cylinders of carbon, not sure about the membrane, but then it has 2 more of those tanks with DI resin. the water comes out of what likes like a gas pump hose. the flow is great. probably take an hour or so to fill a 55 gallon

 

[superkat]

ummm...if you promise not to tell...(cause i'd have to shoot you) this unit was a cast off from the DoD, USAF, B-2 Bomber program, for which I was an Industrial Engineer, hubby was a QA Inspector. We finished up the program and they were throwing this out. We had it hooked up at the house and it was awesome...i almost left it there...but it was a very expensive system (well, for us, for the Air Force it was like a...a box of tissues by comparison...lmao.) and i thought, well...maybe we'll need it. 10 years later......

 

[Buckeye Hydro]

Softeners contain a type of cation resin, rather than the mixed bed resin we use in DI systems in this hobby.

John - recommend you rotate your RO housing so that the outlet ports are above the horizontal centerline of the housing.

Russ

 

[superkat]

thanks, Buckeye...this system is not a standard system. A little different from what a regular consumer would purchase....

 

[johnd651]

your saying so that they point up? will do, any reasoning for it?