Multimedia filters revolutionize water treatment by utilizing diverse filtering media to efficiently remove impurities and clarify water. This process involves passing turbid water through granular or non-granular materials under pressure. Common filter media, such as quartz sand and anthracite coal, effectively trap suspended impurities, offering applications in water softening and pure water pre-treatment.
Filter Media Selection Criteria:
- Mechanical Strength: Ensure resistance to wear and breakage during backwashing.
- Chemical Stability: Opt for media with good chemical stability.
- Safety: Select media free from harmful substances to human health and production.
- Adsorption Capacity: Choose media with high adsorption and interception abilities for improved water quality.
Components of Multimedia Filters:
- Filter Body: Includes cylinder, water distribution assembly, support assembly, backwash air pipe, filter media, and external exhaust valve.
- Supporting Pipelines and Valves: Integral components for efficient filtration.
Operation and Applications: filters, with various media types, effectively remove impurities, adsorb oil, and enable water recycling in industrial circulating water treatment systems. They excel in eliminating tiny particles and bacteria, surpassing sedimentation techniques and exhibiting removal effects on BODs and CODs.
Filter Media Particle Size and Filling Height: The relationship between filter bed height and average particle size (800-1,000 design specification) influences filtration accuracy. Gravel, providing essential support, is arranged in conventional configurations from large to small, from bottom to top.
Common Multimedia Filter Configurations:
- Anthracite coal-quartz sand-magnetite filter
- Activated carbon-quartz sand-magnetite filter
- Activated carbon-quartz sand filter
- Quartz sand-ceramic filter