Rain water and ro systems

[rob92]

So I started collecting rain water to test it and see how it compares to regular tap water.

Test if rain/snow water

Tds 006
Ph 7.4
Ammonia .25
Nitrite 0
Nitrate 0
Phosphates .10

I was thinking if I can collect the rain water and pump it through a RO filtration system I should be able to run for quite a few years before ever needing to change membranes. Also with the TDS being soo low nearly 0, it would cut the waste (brine) water by 90%.

What is everyone's thoughts on this.

 

[McAllyn]

You'd need a pretty decent pump to get up to ~40-65psi to run your RODI unit. After that, I'd be more worried about the chemicals that fall with rainwater, stuff you're not testing for. However, if it worked out, it seems like a great idea.

 

[Kgedelian]

Tds is a measure of the saltiness of the water not purity, Rainwater picks up pollutants in the air that's why we treat it befor we drink it, Any rainwater is not recommended for RO..

 

[rob92]

TDS is not a measure of saltiness if so then why is it on RODI units it's a measure of the total dissolved solids. The measure of saltiness is done by a hydrometer or even better a refractometer

 

[rob92]

You'd need a pretty decent pump to get up to ~40-65psi to run your RODI unit. After that, I'd be more worried about the chemicals that fall with rainwater, stuff you're not testing for. However, if it worked out, it seems like a great idea.

That's why I would send the water through the RODI unit to get rid of the chemicals just like it does for regular tap water. And I was thinking using a water water pump then have a booster pump right before the unit

 

[Marquiseo]

Rainwater picks up pollutants based on your location, rural or urban. Rural areas are less likely to have rainwater with a high amount of pollutants in it unlike urban areas.

 

[rob92]

I live out in the country pretty much surrounded by farm fields in every direction.

 

[SeahorseKeeper]

I live out in the country pretty much surrounded by farm fields in every direction.

I still wouldn't do it. The possibility of the unknown contaminating the water would have me worried. There is a strong possibility of pollutants and pesticides getting into the rain water. If your curious, you can mail a sample of water to a water testing company and get them to test the water.

 

[AZDesertRat]

You could do it and it would work, the RO/DI would remove everything but, the cost to operate a booster pump to take wate rat atmospheric pressure up to 40-80 psi would be prohibitive compared to treating tap water not requiring boosting.