1. **Chemical Dosing Method**: This is the most commonly used approach, involving the addition of scale inhibitors, corrosion inhibitors, and biocides into the water. - **Scale Inhibition**: Agents such as organic phosphonates are used to "sequester" calcium and magnesium ions, preventing them from crystallizing and precipitating. - **Sterilization**: Oxidizing biocides (e.g., hypochlorous acid) and non-oxidizing biocides are used alternately to prevent microorganisms from developing resistance.
2. **Physical Treatment Method**: No chemicals are added to the water; instead, electric fields, magnetic fields, or filtration are used to improve water quality. - **Electrostatic Treatment**: A high-voltage electrostatic field can alter the molecular structure of water, enhancing its scale-dissolving ability and disrupting bacterial cell membranes. - **Filtration and Purification**: Quartz sand filters or side-stream filters are used to remove suspended solids and impurities from the water.
3. **Other New Technologies**: These include using ozone's strong oxidizing properties for sterilization and scale inhibition, as well as biological methods that utilize microorganisms to decompose pollutants. These approaches are more environmentally friendly and produce less wastewater.