Purified water is a specific type of treated water that has undergone advanced processes to remove nearly all contaminants, aiming for a very high level of purity, typically suitable for drinking or sensitive applications. Treated water, on the other hand, is a broader term referring to water that has been processed to meet specific quality standards for its intended use, which can vary widely from drinking to industrial, agricultural, or recreational purposes.
Understanding Treated Water
Water treatment encompasses a wide range of processes designed to make water suitable for a particular use. It is a more extensive process that includes various treatments to meet different water needs. The primary goal of water treatment is to remove harmful substances and make the water safe or appropriate for its intended purpose. This doesn't always mean achieving the highest level of purity, but rather meeting the necessary standards for a specific application.
Key Characteristics of Treated Water:
-
Broad Scope: Applies to water for various uses, including municipal drinking water, industrial processes, agricultural irrigation, and wastewater discharge.
-
Purpose-Driven: The level of treatment depends entirely on the water's intended use. For instance, water treated for irrigation will have different standards than water treated for consumption.
-
Common Processes: Typically involves multiple stages such as:
- Coagulation and Flocculation: Adding chemicals to make small particles clump together.
- Sedimentation: Allowing heavier particles to settle out.
- Filtration: Passing water through layers of sand, gravel, or charcoal to remove suspended solids.
- Disinfection: Killing harmful bacteria and viruses using chlorine, chloramine, or UV light.
- pH Adjustment: Balancing the acidity or alkalinity of the water.
-
Examples of Use:
- Municipal Tap Water: This is treated water designed to be safe for drinking and general household use. It meets safety standards set by regulatory bodies like the Environmental Protection Agency (EPA).
- Industrial Water: Water treated to prevent corrosion, scaling, or contamination in manufacturing processes.
- Wastewater: Treated to be safely discharged back into the environment or reused for non-potable purposes.
Understanding Purified Water
Purified water is a subset of treated water, distinguished by its much higher standard of purity. It is more focused on removing contaminants from water to provide pure drinking water. The objective is to remove virtually all dissolved solids, chemicals, pollutants, and pathogens, resulting in water that is exceptionally clean.
Key Characteristics of Purified Water:
-
High Purity: Removes nearly all impurities, including minerals, chemicals, and microorganisms. The total dissolved solids (TDS) content is typically very low (often less than 10 parts per million).
-
Specific Focus: Primarily aimed at producing water for drinking, laboratory use, medical applications, or other situations where extreme purity is critical.
-
Advanced Processes: Often involves more intensive and advanced purification methods in addition to basic treatment:
- Reverse Osmosis (RO): Pushing water through a semi-permeable membrane to remove dissolved solids, ions, and larger molecules.
- Distillation: Boiling water and collecting the condensed steam, leaving impurities behind.
- Deionization (DI): Using ion-exchange resins to remove mineral ions.
- Ultrafiltration: Using fine membranes to remove suspended solids, colloids, and macromolecules.
- UV Sterilization: Using ultraviolet light to kill bacteria, viruses, and other microorganisms.
-
Examples of Use:
- Bottled Drinking Water: Many commercially bottled waters labeled "purified" undergo these advanced processes.
- Laboratory and Medical Use: Essential for experiments, sensitive equipment, and medical procedures where impurities could interfere or cause harm.
- Pharmaceutical Production: Required for manufacturing drugs and other health products.
Key Differences Between Purified Water and Treated Water
The distinction primarily lies in the degree of purity and the scope of application. While all purified water is treated, not all treated water is purified.
| Feature | Treated Water | Purified Water |
|---|---|---|
| Definition | Water that has undergone processing to make it safe or suitable for a specific intended use. | Water that has undergone extensive processing to remove nearly all contaminants, aiming for a very high level of purity. |
| Goal | To meet minimum safety standards or suitability for various applications (drinking, industrial, agricultural). | To achieve maximum purity by removing almost all dissolved solids, chemicals, and microorganisms, typically for consumption or sensitive applications. |
| Scope | Broader; "more extensive and includes various treatments for water to meet different water needs." | Narrower; "more focused on removing contaminants from water to provide pure drinking water" or for specific high-purity needs. |
| Purity Level | Varies; generally safe but may contain minerals and trace elements. | Extremely high; very low or zero Total Dissolved Solids (TDS). |
| Processes | Filtration, coagulation, sedimentation, disinfection (e.g., chlorination), pH adjustment. | Includes advanced methods like Reverse Osmosis, Distillation, Deionization, Ultrafiltration, in addition to basic filtration and disinfection. |
| Typical Uses | Municipal tap water, industrial water, irrigation, recreational water (pools). | Bottled drinking water, laboratory experiments, medical applications, pharmaceutical manufacturing, specific electronics cleaning. |
| Cost | Generally less expensive to produce in large quantities for general use. | More expensive due to the advanced technologies and energy required for extensive purification. |
Practical Insights
- Choosing Your Water: For daily drinking, municipal tap water (which is treated water) is generally safe and often contains beneficial minerals. However, for those seeking to eliminate virtually all substances from their drinking water, or for specific health conditions, purified water may be preferred.
- Health Considerations: While purified water removes contaminants, it also strips beneficial minerals. Long-term consumption of highly purified water without mineral reintroduction can be a consideration, though most people get sufficient minerals from their diet. The World Health Organization (WHO) provides guidelines on drinking water quality.
- Home Solutions: Home water filters (pitcher filters, faucet filters) generally provide additional treatment by removing taste, odor, and some contaminants, but they typically don't achieve the high purity of commercially purified water. Whole-house filtration systems offer more comprehensive treatment, while home reverse osmosis systems can produce purified water.
In essence, while both types of water undergo processing, the key differentiator is the degree of purification and the intended application. Treated water is made safe and suitable for its purpose, while purified water goes further to achieve an exceptionally high level of cleanliness.
