Hard Water & Choosing a Water Softening System
“Hard” water is high in dissolved minerals, mainly calcium and magnesium. Though hard water does not pose a health risk, it can form hard scale deposits that can build up on piping, heat exchangers, water heaters, boilers, and steam related equipment. These deposits result in costly repairs, premature equipment and fixture failure, reduced efficiency, and increased energy consumption. Hard water minerals can also impede soap and detergent performance and reduce the service life of linens and other laundry in health care facilities and hotels.
In the U.S., water is categorized as soft, slightly hard, moderately hard, hard, or very hard depending on the parts per million (ppm) of dissolved minerals. To determine hardness, water can be tested a simple test kit, or the local water utility can advise as to the hardness of the water supply. If water is hard, or very hard, water softening equipment should be considered to prevent scale deposits.
The two most widely used types of water softening systems are ion exchange (IX) and reverse osmosis (RO), and each has its advantages and disadvantages depending on the application. An IX system reduces hardness by replacing magnesium and calcium with sodium or potassium ions. RO systems force water through a semi-permeable membrane that filters out dissolved minerals, organics and other particles. If dissolved minerals levels are particularly high, an RO system may be more economical due to the increased amount of chemicals that would be required in an IX system. RO creates more waste water than IX (20-50% vs. 4%), though it may still be suitable for a secondary use such as cooling. IX systems produce a higher quality of water and are not subject to sudden failure, whereas a ruptured RO membrane would require immediate plant shutdown.
PJM Mechanical Contractors, Inc. is a multi-faceted mechanical contractor providing construction and installation, service and maintenance, and design/build services in a comprehensive range of mechanical disciplines that include HVAC, plumbing, controls, refrigeration, custom metal fabrication, piping, fire protection, and backflow preventer testing. PJM primarily serves clients in pharmaceuticals, manufacturing, healthcare, institutional, and other various commercial and industrial sectors.