40 Years Ago I Installed my First High Purity System
A few days ago, I was rummaging through some old slides and I stumbled across one from 1979. It was of the very first installation of an RO - DI system in an Indiana hospital. Back then, nearly every hospital used a steam distiller for high purity water, which was both expensive and labor-intensive. They contacted me to solve that problem.
I have to admit that I knew very little about this type of system, but it only seemed logical that it would include reverse osmosis and deionization. I'm sure that I was not the first one to do this, but there weren't many others. There was not a roadmap that I knew of, so I set out to design the system. As it ended up, it included the following
- 2 Miracle Water "Series One" Water Softeners - I did that so soft water would always be available. This was long before twin-alternating softeners like the 9000 or 9100;
- 20" Carbon Pre-Filter - In retrospect, I should have used a carbon tank instead of a cartridge, but "live and learn."
- 2,000 GPD Reverse Osmosis System - Using a Procon Rotary Vane Pump and a 4" x 40" Membrane. Again, I have learned that a true commercial system should not include a rotary-vane pump. I now use a stainless steel centrifugal pump. I would also now use three 2-1/2" by 40" membranes to deliver the same flow. That would enable me to waste just 1 gallon of water for every 4 gallons produced.
- Storage Tank - I don't remember the size and storage tanks back then were not readily available. It was likely around 200 gallons.
- Portstar Ultraviolet Disinfection - Designed to assure that the water is bacterially pure and that any airborne bacteria cannot survive.
- Repressurization Pump - Since the water is stored in an atmospheric tank, not under pressure) it has to be re-pressurized for delivery to wherever the water is needed.
- DI Tanks - We used two Deionization tanks, but now we use DI cartridges because we get much higher quality from reverse osmosis membranes. This means that tanks are dinosaurs. They no longer make sense.
Things have not changed a lot in the 40 years since I installed that system. The basic principles are the same. We don't use water softeners that much anymore, Instead we prefer "anti-scalant" systems. We also use carbon tanks to remove chlorine and chloramine which are detrimental to RO membranes.
Additionally, we have "quality lights" to monitor the water quality and instrumentation that measures the exact water quality digitally. Finally, we frequently include a 0.2-micron final filter and possibly a UV that has a TOC removal bulb.
We have been providing high purity and laboratory water for quite a long time.. over 40 years in fact. I would be remiss if I did not tell you that we are the real experts in this type of water treatment.