Are All Residential Water Distillers Created Equal?

It would be much cheaper, from an energy consumption point of view (by a factor of 200-400!), to use reverse osmosis [RO] instead of distillation. However, distillation is very tolerant to suspended solids in the water, and in some cases less pretreatment equipment is needed. RO suffers should free chlorine be present in the feedwater, and fouling from suspended solids can also be a hazard, making pretreatment necessary upstream of it.

Both processes are used to make drinking water from seawater in such locations as oil and gas platforms, ocean-going vessels, etc.

Without a water analysis and an energy tariff it is very difficult to advise which is better. However here are some thoughts:

• Is it possible to relocate the carbon filters in some way so that they are in use only on the water used for cooking and drinking, thereby extending the cartridge life many-fold?
• Is it possible to put a pretreatment cartridge depth filter of, say, 5μm nominal rating upstream of these?
• Many major home improvement stores sell D-I-Y water improvement systems and it may be worth a walk round the shelves first to see what could be done relatively cheaply. So far, home RO systems are not sold in this way locally.

You might check here for a whole-house water treatment system:

http://www.ecoquestintl.com/CatalogProduct.aspx?ProductId=3579

Click on the "Specifications" tab for more info.

And just for full disclousre, I do have a connection to this company.

How about putting in a small 3 chamber pool filter upline?

Heavily chlorinated water will significantly shorten the life of an activated carbon filter. If this is the problem you are dealing with, the only way I know of to reduce residual chlorine content is let the water set for a period of time- it helps to stir it up. If, on the other hand, the problem is with excessive dissolved solids and minerals, a prefilter will definitely help (but will most likely need frequent servicing or replacement as well.

One solution you may want to consider is an ozone treatment system. Ozone is generally used as a sterilizer (like chlorine), but it has the added avantage that it can reduce dissolved solids by oxidizing them into a heavier compound that will settle out of the water.

If you feed your raw water into a storage tank, say 1000 gallons or so, then use a swimming pool ozone generator configured such that the ozone bubbles up from the bottom of the tank, it will stir the water up (helping to evaporate the excess chlorine) while reducing the other contaminants through oxidation. You may want two tanks, one that you use after treatment, a second that is undergoing treatment. Try to size the tanks so that the water resides in the tanks for at least 3 days before you use it. Then filter through a paper or sand filter, then activated carbon, and you should have reasonably inexpensive and good quality water.

I originally started using this approach for treating rainwater, and found that it greatly improves the public utility supply as well.

I beg to differ!

Amount of Chlorine in water will NOT reduce the life of (AC)activated carbon.Removal of chlorine is just a catalytic reaction. But amount of organic matter present in water will significantly reduce the life of AC.

You to do not have to keep water in storage after sterilization (with ozone or chlorine). You can send treated water immediately through an AC filter.

Using a prefilter before the AC filter is certainly preferable as you do not want your horse to the dog's work (with apologies to both!)

I too think for OP's problem RO with some pretreatment is the best solution.

GA from me as you said it all in a simple easily understood manner.....

Hi Andy,

You are giving GA for a factually incorrect answer. I request you to reconsider your decision.

CWarner7_11, please this is nothing personal against you. I have 26 years experience in Activated Carbon and I wanted to correct this wrong belief among a lot of people.

AC works on the principle of adsorption to remove organic matter and other micro pollutants, but in dechlorination it acts in a completely different manner!

Although you have corrected my knowledge on one minor point, the rest of his post was excellent.

There are so many posts on CR4 that are 2000% wrong (if that was even possible!), here one minor point.....forget it!!

I see no reason to remove the GA.

Thanks anyway.

What I intended when discussing the effect of chlorine on activated carbon was not the removal of chlorine, but, rather, using chlorinated water with activated carbon will significantly reduce the efficacy and life expectancy of the activated carbon, not that the activated carbon was intended to remove the chlorine. The level of the chlorine will decrease through evaporation if you let the water stand for a period of time (three days was an estimate based on water I am familiar with. The level of residual chlorine in the water will have a significant impact on how long it must stand to reduce the level to tolerable limits).

Still the statement "using chlorinated water with activated carbon will significantly reduce the efficacy and the life expectancy of activated carbon" is wrong!

Sorry cwarner7-11 with due respect to you i must point this out for the benefit of others who look for correct knowledge in CR4 forum.

Contrary to what you say if water is chlorinated before sending it to activated carbon bed efficacy & life expectancy of AC improves as chlorinated water has less organic matter to contend with . These are scientific facts and not just observations.

Your observation that free chlorine will decrease when water is kept in storage in absolutely correct. People in this part of the world who get chlorinated water supplies by public water lines usually used to prefer to have storage tanks. But with popular use of AC for dechlorination and also removal of harmful Tri halo methanes now unless you need emergency supply you do not need storage in your own house.

Actually you do not have to keep chlorinated water stored for 3 days, but within a day all traces of free chlorine will be gone in less than 24 hours. At the same time you run the risk of downstream recontamination when you do this.

I have a lot of experience designing Activated carbon beds for water purification systems and I am just trying to share my knowledge with you all.

By the way cwarner7_11 your comment No 12 in response to my comment no 6, contains 100% correct facts,. Why did you mark it off topic?

Its not possible (unless you are the Admin) to know who gave you an OT, unless they tell you so. Did he tell you that?

I am not admin! I am just a very simple person in CR4. Just 29 years of experience in small matters like manufacture of Activated carbon, design of AC filter systems etc.
I just happened to have some minor academic qualifications ..just 2 degrees in Mechanical engineering & Computer IT.

I have gained a lot of knowledge from CR4 and also try ro reciprocate my best by contributing with my limited knowledge.

I reproduce here part of my comment on which you have commented
" By the way cwarner7_11 your comment No 12 in response to my comment no 6, contains 100% correct facts,. Why did you mark it off topic?"
He did not tell me. I do not know him personally. Whatever my correspondence I have with cwarner7_11 is on CR4 forum transparent to all. I just assumed him to have marked his own comment as OT. Apparently CR4 has some mysterious mechanism to do the OT as explained in post 19 by cwarner7_11 himself/herself (pardon me cwarner7_11, i am trying to add some humour!)

I have a concept for the manufacture of a unit to recover water by distillation using waste heat &/or solar but I do not have the facilty to build it. Anyone out there with plumbing experience and equipment interested ???

How stupid it was for all of us trying to help OP without really knowing what exactly the problem is? Our answers were based mostly on assumptions which may not be the case with OP.

I give my GA for you, for as you rightly said looking at it from a different & (if i may add) Correct perspective.

GA Jman, I guess that I need to become more verbose before I get a GA for the simpelest, cost effective answer r.e. #4. It was my assumption that the water quality was suffering from asthetics rather than toxics since the filter used was only clogging up, and the water was otherwise useable. The pool filter I reccomended would take care of that, followed up by the already installed carbon filter.

Many bloggers ask blanket questions, for which we are left guessing about the original symptoms of thier discontent. Perhaps before asking for help it would be made clear to them that the question needed to be phrased compleatly. You got to the heart of that matter. Good thinking. Are you a teacher?

Yes, we have some big costs with water filters diminishing effectivity, & rising pathogen rates plugging them up from the first gallon drawn.There is a company which is what you describe with stainless steel boiling chambers,10 gal storage tanks stacked on neat black stands, & a (VOC) "volatile organic compound" relief venting system, & just 1 charcoal filter cartridge which fits into storage tank, at base of distillers condensation coil.Pureandsecure.com If you need further help let me know so I can follow-up. Sincerely,Ecohelpfull

Any suckers..!

You should consider a pre filter before your carbon filter, to remove any larger suspended solids, say up to 20 or 30 um. That will help increase the life of the carbon filter.

Asking about distillation, are you looking for disinfection / removal of bacteria? Have you considered UV for a disinfection method? It would expect it to be more energy efficeint thatn distilation.

check out www.natureflow.com.au they have a good product.