Water Purification Technologies – Pulling It All Together

　　Combining Water Purification Techniques for Enhanced Efficiency
Water purification systems require a blend of technologies to effectively address the diverse range of contaminants present. Relying on a single purification method is insufficient for achieving the stringent purity levels demanded by sensitive applications. A well-designed purification setup combines multiple technologies to reach the desired water quality standards. These purification methods must be sequentially arranged to optimize their contaminant removal capabilities. The diagram below depicts a sophisticated central laboratory water purification system designed for critical use.

　　The purification process begins with pretreatment stages, which are carefully designed to target specific contaminants found in the source water. Pretreatment is crucial for minimizing substances that could affect later purification stages, especially reverse osmosis (RO) systems. This includes carbon filtration to remove chlorine, particulate filters to eliminate sediment and silt, and softening agents to decrease water hardness minerals.

　　Following pretreatment, the Reverse Osmosis (RO) phase can eliminate 90 to 99% of waterborne contaminants. RO is a cornerstone of any robust purification assembly due to its effectiveness in removing a broad range of contaminants. However, the RO membrane’s tight pore structure limits flow rate, necessitating the use of storage to collect and distribute water to various points-of-use, including additional polishing systems.

　　Polishing systems further purify pretreated water, such as RO water, by removing any trace contaminants, achieving "Type I" or "ultrapure" water quality. These systems are specifically designed to remove residual impurities from water that has already received primary treatment, such as reverse osmosis or deionization. Using such a system directly on untreated tap water would quickly diminish its capacity and affect the end quality.

　　A typical polishing system may include activated carbon, mixed-bed deionization, organic scavenging mixtures, and 0.22 μm final filtration. The system can also be supplemented with ultrafiltration, UV oxidation, or other features customized for particular applications. This integration of purification technologies, combined with suitable pretreatment, results in water that is nearly free of ionic, organic, and microbial contaminants.

　　For more information on individual technologies and their integration, refer to: Distillation, Ion Exchange, Carbon Adsorption, Ultrafiltration, Reverse Osmosis, and Ultraviolet (UV) Radiation.