Industrial Reverse Osmosis vs. Industrial Deionization

Two of the leading methods for water purification for industrial and commercial environments are Twin Bed Deionization (also called strong base demineralization or Two Bed De-Ionization or DI) and Reverse Osmosis (RO). While they obtain roughly the same results, choosing between them for your industry’s pure water can be difficult.

Here is how to compare industrial reverse osmosis vs. industrial deionization to determine which is the best match for your industrial water purification needs.

Industrial Reverse Osmosis (RO)

The newer technique of the two, industrial reverse osmosis, or industrial RO, has only become widely available within the last few decades. Industrial reverse osmosis is a diffusion process that runs water through a semipermeable membrane against the concentration gradient, which in turn catches and removes ions and larger molecules. Today, commercial and industrial reverse osmosis systems are usually the preferred method for removing the majority of TDS (Total Dissolved Solids) in water. (Notably, for polishing the water to ultra or a super high purity level, mixed bed deionizers (DI) or electrodeionization (EDI) is needed.) For more information on the reverse osmosis process theory, visit our page on industrial reverse osmosis.

Pros of Industrial Reverse Osmosis

• Industrial reverse osmosis systems remove up to 99% of dissolved mineral salts, organics and other particles.

• No chemicals or permits are required with industrial reverse osmosis.

• Industrial reverse osmosis is a very environmentally friendly process.

• Capital and operation costs are usually much lower with industrial reverse osmosis systems than with industrial two bed deionization systems.

• Industrial reverse osmosis maintenance is easy and system operation is relatively low compared to twin bed DI systems.

• Industrial RO systems perform well in high TDS water.

• Industrial RO systems are great for desalination and removal of impurities like ethanol.

Cons of Industrial Reverse Osmosis

• Industrial reverse osmosis usually requires some sort of pretreatment equipment (e.g. industrial water softeners, ML or AG+ filters, carbon filters) or a small chemical treatment feed.

• Certain water chemistries do not work well in reverse osmosis systems (e.g. high silica or barium levels could cause scaling).

• Water needs to be temporarily stored and re-pressurized with industrial reverse osmosis.

• Incoming water with fine silt or other small suspended solids that are hard to catch in a pre-filter can lead to membrane plugging in industrial reverse osmosis systems. Industrial nanofiltration systems can be used, but are expensive.

• Industrial reverse osmosis equipment has a more limited temperature range than DI systems have.

Industrial Twin Bed Deionization (DI)

As is clear from its name, deionization (also often written as de-ionization) is the process of removing ions from water. Twin bed de-ionization (or demineralization, as it’s sometimes called) is accomplished by running water through two ion exchange columns, first a cation DI tank and then an anion DI tank. One tank removes all the cations in the water and the other all the anions.  For more information on the process theory, visit our industrial deionization page.

Pros of Industrial Two-Bed Deionization

• Industrial deionization is a tried and true method that is widely accessible. It is perfect for certain water chemistry, temperature, and quality issues.

• Capital costs of DI systems with high flow rates can be much more cost effective than reverse osmosis with certain water chemistries (e.g. low TDS ~ 150-250ppm).

• Industrial deionizers can be used with higher temperatures than reverse osmosis systems.

• For some water chemistries, demineralizers (another name for industrial de-ionization) will perform better than reverse osmosis systems.

• Industrial deionization can handle a higher temperature range than reverse osmosis as well.

• Deionization can handle a wider range of water chemistries than reverse osmosis equipment.

• Industrial deionization doesn’t usually require any pretreatment equipment (industrial water softeners, carbon filters, ML or AG+ Filters).

Cons of Industrial Two-Bed Deionization

• Industrial deionization uses a process that can be dangerous to workers due to the use of acids and caustic chemicals for regeneration.

• Permits for the chemicals are often needed and having hazardous materials on site can increase insurance costs with industrial deionizers.

• Operating costs are usually much higher with industrial twin bed deionization systems.

• Initial capital costs for industrial deionizers are usually higher than with industrial RO equipment.

So, which is right for you:  industrial twin bed deionization or industrial reverse osmosis? There is no fail-proof formula for making that decision – it really ends up being a case-by-case issue. The best thing to do is contact us at 800-820-9021 or info@industrialh2osolutions.com to help point you in the right direction.

Do you need repair or preventative maintenance? Contact Industrial Water Solutions at 800-820-9021 or info@industrialh2osolutions.com for:

• Service and repair of industrial deionizers, reverse osmosis, and filters
• Preventative maintenance and training (PMT) for deionizers, reverse osmosis, and filters
• Parts for water softeners, deionizers, reverse osmosis, and filters

Also see our helpful resources and industrial water technical articles for industrial water softeners, reverse osmosis, deionization, filters, brine tanks, and more.