Water Treatment Solutions for Powder Coating

At Reynolds Culligan, we supply industrial and commercial water treatment systems for a wide range of applications and processes. They help reduce and remove unwanted chemicals and compounds in source water to bring it up to operation-appropriate standards. As a result, they can help increase water quality, protect processing and handling equipment, improve equipment performance, and/or enhance process efficiency and effectiveness. One use case for our water treatment solutions is powder coating operations.

What Is Powder Coating?

Powder coating is a finishing process that involves applying dry thermoplastic or thermoset powder to the surface of a material and heating, melting, and drying it to form a protective and/or decorative coating. It is often used to finish industrial tools and equipment.

The Importance of Water Treatment for Powder Coating Operations

The powder coating process has three stages—surface preparation, material application, and curing—each of which utilizes distinct tools and carries specific requirements to achieve a durable and aesthetic finish. The surface preparation stage ensures the application surface is fully clear of any chemicals or compounds that could negatively affect the quality of the coating. Water treatment systems ensure the rinse water, which removes any dissolved and undissolved solids from the application surface that may have been deposited by previous steps, does not add any new compounds to the application surface.

Photo of three colors of powder coating

Types of Water Treatment Systems for Powder Coating Operations

Three of the most common water treatment systems used for powder coating operations are deionized water systems, water softeners, and reverse osmosis filters.

Deionized Water Systems

Deionization water systems work by employing specialized ion exchange resin compounds that physically bind to mineral salts. As the water flows through the resin bed, all of the solids are removed from it. When the resin bed is exhausted, it is replaced with a fresh tank.

Coating companies generally utilize deionized (DI) water during the final rinsing steps since it does not contain any dissolved minerals. As a result, it does not leave any compounds on the surface of the material.

Water Softeners

Water softeners replace the calcium, magnesium, and other minerals in source water with sodium. As sodium is more soluble than these compounds, it is less likely to produce hard scale within powder coating equipment (e.g., nozzles, tanks, and heated washers). However, the increase in sodium can raise the total dissolved solids (TDS) level if the facility does not employ adequate or complete back flushing measures.

Softened water is not suitable for use during rinsing stages preceding or following phosphate conversion coating operations or final rinsing stages. Compared to untreated hard water, it contains solids that are more soluble and conducive to corrosion.

Reverse Osmosis (RO) Filters

Reverse osmosis (RO) water treatment systems filter out suspended and dissolved solids from source water by forcing it through semi-permeable membranes. These membranes can remove various minerals that affect pretreatment and application, depending on the specific design and construction.

Compared to water softeners, RO systems achieve and maintain much lower TDS levels (between 50–250 ppm), making them highly suitable for treating source water with significantly high TDS levels. Compared to deionized water systems, they carry a higher short-term investment cost but lower long-term maintenance costs. Additionally, they are ideal for applications that require high volumes of treated water. Water treated through reverse osmosis can be used to improve coating performance and/or reduce pretreatment chemical usage in chemical bath operations.

Water Treatment Solutions for Powder Coating at Reynolds Culligan

At Reynolds Culligan, we’ve provided single-source, comprehensive water treatment solutions for a wide range of industries and applications since 1948. Data logging, remote monitoring, and telemetry technology allows us to carefully examine and evaluate the performance of our water treatment systems. This information enables our customers to determine if and when their systems are inconsistent and their processes need improvement.

Whether you need deionized water systems, water softeners, or reverse osmosis filters, we’ve got you covered. To learn more about the importance of water treatment in powder coating operations or how we serve the powder coating industry, contact our team today.