Portable Service DI Tank Exchange

Puretec's Portable Deionized / Demineralized Water Tank Exchange Service is a safe and economical way to achieve a dependable supply of high purity deionized water.

Portable Service Exchange DI Tanks

Portable ion exchange service consists of movable tanks or cylinders ranging in volume from 0.5 cubic feet to 45 cubic feet which incorporate different ion exchange resin types and tank sizes to accommodate different quality and flow rate requirements. The ion exchange tanks remove ionic contaminants that are harmful to many industrial and commercial processes. Eventually the ion exchange tanks reach exhaustion after a certain amount of use and are unable to remove ionic impurities and this is when Puretec will send a service technician to remove the exhausted tanks onsite and replace them with freshly regenerated tanks. All of the equipment, ion exchange resins, regeneration, maintenance and repair is provided by Puretec.

DI Tanks_Larger

Our DI Water Tanks require no chemical handling or maintenance and provide a reliable source of deionized water (also called demineralized water) up to 18.2 Mega-ohm resistivity. The DI Water tanks come in various sizes, ion exchange resin types and flexible configurations to meet your process water needs with many quality-monitoring options available. We offer same day/next day service and are able to respond 24/7 to emergencies.


Each customer is unique. We recommend the most economical and reliable service unit type for their application, water quality requirements and demand. DI Water tanks can be provided on an as needed basis, a scheduled frequency or as part of a broader preventative maintenance service for your water system. We handle everything from installation to service and take pride in having a strong service culture that focuses on quality and customer satisfaction.


All ion exchange resins are regenerated under current Good Manufacturing Practices in compliance with ISO 9001 standards. Only premium ion exchange resins are used to ensure consistent performance and throughput. Each batch of ion exchange resin is tested multiple times throughout the regeneration process for both quality of effluent and throughput capacity. This guarantees the proper water quality and a predictable run length. For critical laboratory, pharmaceutical, medical and research applications that adhere to USP, CAP/NCCLS/CLSI, ASTM, ISO 3696, GRADE 1-3/TYPE I-IV, and "Milli-Q Water" applications, dedicated and isolated service deionization tanks are available along with full documentation and traceability.

Basics of Ion Exchange/Demineralization

Ion Exchange Diagram Color

Deionization (also referred to as demineralization) is one of the most efficient processes for removing ionic dissolved salts and minerals from water. Ion exchange is a process where troublesome ions are exchanged for more desirable ions by using specially manufactured ion exchange resins. Ions are dissolved salts or minerals in water that can cause problems in high purity water systems when used as a rinse, coolant or a product ingredient. The purpose of ion exchange is to employ the correct type of ion exchange resins to remove the ionic contaminants that are unacceptable for the customer and replace them with ions that allow the customer to operate without problems. This process provides water that can remove nearly all dissolved salts and gases providing water that is high purity water that is similar to distilled water. The best ion exchange system for you depends on the quality of water entering the system and the quality of water that you require out of the system. By using the proper ion exchange resins it is possible to provide the optimal system for your application.

Granular Activated Carbon (GAC)

GAC removes chlorine and chloramines as well as many dissolved organic contaminants. It does not function on the principles of ion exchange, but a GAC unit is commonly found as part of an ion exchange system or before an RO unit to prevent damage from oxidation or organic fouling.

Dual Bed Systems

A dual bed system consists of (at a minimum) a Cation demineralizer followed by either a Strong Base or Weak Base demineralizer.  A Cation Demineralizer exchanges positively charged ionic contaminants such as calcium, magnesium, iron, manganese, potassium and sodium with the hydrogen (H+) ion.  A Strong Base Anion Demineralizer exchanges negatively charged dissolved ionic contaminants such as chlorides, alkalinity (carbonate and bicarbonates), CO2 gas, sulfates, nitrates and silica for the hydroxyl ion (OH-). A Weak Base Anion Demineralizer removes the above contaminants with the exception of silica and C02.  The resulting stream of water will consist of hydrogen (H+) and hydroxyl (OH-) that together form H20.  Due to the inevitable sodium leakage in a dual bed system, you will not achieve complete deionization. You can expect to see water quality with a resistivity up to 200,000 ohms-cm (2.5 ppm TDS).  A Cation-Strong Base demineralizer will produce a higher than average pH, while a Cation-Weak Base system will produce a lower than average pH.  Additional ion exchange tanks can be added to a dual bed system to achieve desired water quality results. For example, a mixed bed ion exchange tank can be added after a dual bed system to ‘polish’ the water up to 18.2 Mega-ohms resistivity.

Mixed Bed Deionizers

Mixed Bed Deionizers consist of Strong Acid Cation and Strong Base Anion ion exchange resins mixed together to produce a higher quality of deionized water with a more neutral pH than dual bed systems. You can expect to see water quality with a resistivity of up to 18.2 Mega-ohms (the highest possible level of deionization/distillation available). Often a dual bed system or RO system will be placed before a mixed bed deionizer, which provides the user with a very reliable high purity source of water. In line conductivity/resistivity meters alert users when the ion exchange tanks need to be replaced with fresh bottles.

Type Resistivity Conductivity TDS pH
Mixed Bed ≤18.2 Ω ≥0.056 µ ≥0 ppm Neutral
Cation-Stong Base Anion ≤200K Ω ≥5 µ ≥2.5 ppm >7
Cation-Weak Base Anion ≤100K Ω ≥10 µ ≥5 ppm <7

Puretec Industrial Water provides a complete line of water treatment services and parts across California, Arizona, Nevada, and New Mexico.