Water purification systems

Selection of operational and process units

All water sources contain a wide range of organic and inorganic impurities. Water purification is the removal of undesirable components from water and then their disposal in the easiest and safest way. To achieve this goal, various purification processes are used that use different physical and chemical phenomena to remove or reduce undesirable components from water. The selection of purification processes is one of the keys to the successful operation of any water treatment plant. Engineering decisions made at this stage can have a significant impact on the cost of the entire project. A mistake in the selection of a process may necessitate costly changes in operation to meet the quality standards of the treated water.

Combining process and operational units in a purification pattern

Many process and operational units can be combined in a purification pattern to achieve the desired degree of purification in order to meet drinking water quality standards. The degree of purification may range from the removal of turbidity, taste and odor to the complete removal of minerals. Selecting the right process and developing an overall purification model is not an easy task. It requires understanding the processes, their performance, and their capabilities.

Treatment Pattern for New Systems

Experiences gained from treating a similar water source are a good guide in providing a treatment pattern for new systems.

Factors that influence the selection of a treatment pattern

• Ability to meet treated water quality objectives, taking into account seasonal and long-term variations in raw water quality
• Topography and site conditions, existing treatment facilities, available land area, and hydraulic considerations
• Reliability of the overall system
• Flexibility and ease of operation
• Ability of the process to upgrade performance in cases where water quality or drinking water standards change
• Ability of the process to control hydraulic shocks
• Availability of specialized operation and maintenance personnel, major equipment, and chemical distribution system
• Government regulatory requirements
• Preferences and experience of the design engineer
• Ease of construction of the facility
• Construction and operating costs