Free installation + 2-year warranty on every purifier · Installation and service across Mangaluru, Bengaluru and nearby towns · Book a lab test
DM water plants (two-bed demineraliser)
A two-bed DM plant passes water through cation resin, then anion resin, and takes out the dissolved salts that an RO leaves behind. A Puryn two-bed plant gives water below 10 µS/cm, read on an online conductivity meter, and is regenerated on site with hydrochloric acid and caustic soda. Fed from an RO plant, it runs much longer between regenerations. Built and installed by our Bengaluru team.
- Below 10 µS/cm conductivity
- Online conductivity meter
- Regenerated on site
- Can follow an existing RO plant
- Installation included
- Payment 50% to book, 50% on installation
A typical Puryn 500 LPH two-bed DM plant
- Output
- Below 10 µS/cm conductivity
- Vessels
- 2 FRP pressure vessels, cation and anion
- Resin
- Strong acid cation and strong base anion
- Valves
- Manual multiport, 25 NB
- Feed
- 0.5 HP pump
- Reading
- Online conductivity meter, flow meter, 2 gauges
- Regeneration
- Acid and alkali tanks with ejectors
- Site
- Water point, drain, single-phase power
Check what your equipment needs first. Two-bed DM suits batteries, boilers, glassware and most autoclaves. Clinical analysers usually need purer water than that, which we build differently.
What do you need the water for?
Different equipment needs different purity. This is how we match it.
| Use | Two-bed DM? | What we suggest |
|---|---|---|
| Battery topping water | Yes | Two-bed DM |
| Boiler and cooling tower make-up | Yes | RO, then two-bed DM for longer runs |
| Lab glassware rinsing | Yes | Two-bed DM |
| Tabletop autoclaves | Usually | Two-bed DM with carbon and sediment pre-filters. Check the autoclave manual. |
| Clinical analysers (Type II lab water, 1 µS/cm or better) | No | RO followed by mixed-bed polishing, UV and a 0.2 micron filter |
| Drinking water | No | RO plant or a Puryn purifier |
Send us the water spec
Most manuals list the conductivity or resistivity they need. Send us that page and we will tell you whether a two-bed plant meets it.
Two vessels, two resins, one meter.
Water passes the cation resin, which swaps calcium, magnesium and sodium for hydrogen ions, then the anion resin, which swaps chloride, sulphate and nitrate for hydroxide. Hydrogen and hydroxide become water. The meter tells you when the resins are spent.
Feed pump
Draws raw water, or RO product water for longer runs.
Cation vessel
Strong acid cation resin in an FRP vessel with a multiport valve.
Anion vessel
Strong base anion resin in a second FRP vessel.
Conductivity meter
Online cell shows the water quality all the time.
Regeneration
When the reading rises: acid through the cation, caustic through the anion, using the ejectors. Then rinse.
Feed it from an RO plant
A DM plant on raw borewell water exhausts its resin quickly. Put it after an RO plant and it runs many times longer between regenerations, with less acid and caustic used.
What is in a 500 LPH two-bed plant
From a recent Puryn quotation. Larger plants use bigger vessels and more resin.
| Item | Specification | Qty |
|---|---|---|
| Skid | 25 mm frame | 1 |
| Cation exchanger | FRP pressure vessel 1054 | 1 |
| Anion exchanger | FRP pressure vessel 1054 | 1 |
| Valves | Manual multiport valve, 25 NB, top-mount | 2 |
| Cation resin | Strong acid cation | 25 L |
| Anion resin | Strong base anion | 25 L |
| Feed pump | 0.5 HP | 1 |
| Regeneration | Acid tank, alkali tank, ejectors | 1 + 1 + 2 |
| Instruments | Online conductivity meter with cell, flow meter, pressure gauges | 1 + 1 + 2 |
| Treated water | Conductivity below 10 µS/cm |
iConductivity
Measured in µS/cm. Lower is purer. Raw borewell water is often several hundred; a two-bed DM plant takes it below 10.
iRegeneration chemicals
Hydrochloric acid and caustic soda, supplied by you. We show your staff the regeneration steps at handover.
iRun length
Depends on the TDS of the feed water and the litres you draw. RO feed water stretches it a long way.
What it needs at your site
What to have ready
- A water pointRaw water, or the RO plant outlet.
- A drainFor regeneration and rinse water. Keep acid and caustic waste away from metal drains.
- A single-phase power pointFor the feed pump and the conductivity meter.
- A safe place for chemicalsAcid and caustic soda stored apart, away from sunlight.
What our technicians do
- Visit the site and test the feed water.
- Confirm the purity your equipment needs.
- Install the skid, vessels, pump and instruments.
- Run the first service cycle and read the conductivity with you.
- Train your staff on the regeneration steps, with safety gear.
Tell us what the water is for
WhatsApp the equipment name, its water spec if you have it, and how many litres a day you use. We tell you whether a two-bed plant fits or what does.
Send the use
Battery room, boiler, lab, autoclave: and the litres a day.
We match the purity
Two-bed DM, RO plus DM, or RO plus mixed-bed polishing.
Visit and quote
A site visit and a written quotation.
Tell us what you need.
The use, the litres a day and the water source. Our Bengaluru team will call you within 24 hours.
Frequently asked questions
What is a DM water plant?
A demineralisation plant. Water passes through cation resin and then anion resin, which take out dissolved salts. A two-bed plant gives water below 10 µS/cm conductivity.
DM or RO: which do I need?
RO takes out most dissolved salts and is the usual first stage. DM goes further. For many uses, an RO plant followed by a two-bed DM plant gives the best water for the least chemical use.
Is two-bed DM water good enough for a clinical analyser?
Usually not. Fully automatic analysers typically need Type II lab water of 1 µS/cm or better. For those we build RO followed by mixed-bed polishing, UV and a 0.2 micron filter.
How often does a DM plant need regeneration?
When the conductivity meter shows the reading rising. How long that takes depends on the feed water TDS and the litres you draw; RO feed water makes it last much longer.
Who supplies the regeneration chemicals?
You do: hydrochloric acid and caustic soda. We show your staff how to regenerate safely at handover.
Can I drink DM water?
No. DM water is for equipment and process use. For drinking water, use an RO plant or a Puryn purifier.
What are the payment terms?
50% advance to book and 50% on installation. GST is extra and invoiced by Puryn International.
How does the lab test work?
You get two lab reports: a pre-treatment report before we recommend anything and a post-treatment report after installation. Both, worth ₹2,000, are included in the price of your system. You pay ₹1,000 when we take the first sample, and it is adjusted when you order. For example, on a ₹65,000 system you pay the remaining ₹64,000.
Guides and related pages
Need DM water on site?
Tell us what the water is for. We match the purity and quote in writing.
