Sand Filters & Gravity Filters
Sand Filters & Gravity Filters
Sand filters and gravity filters are essential components of water and wastewater treatment systems, providing reliable and cost-effective filtration for municipal, industrial, commercial and desalination applications. Using layers of sand or multimedia to remove suspended solids, these filters offer high flow capacity, low operating costs and robust performance. Tecpro Australia supplies high-quality filter nozzles, under-drain components and supporting spray equipment to optimise the operation and efficiency of sand and gravity filtration systems.
How Sand & Gravity Filters Work
Sand filters and gravity filters operate by allowing water to flow downward through a bed of sand or multimedia. As water passes through the media:
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Suspended solids are trapped within the filter bed
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Turbidity and particulate matter are removed
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The water leaving the filter meets required clarity and quality standards
Over time, accumulated solids are removed by backwashing the filter. Filter nozzles play a critical role in distributing the flow evenly during both filtering and backwashing cycles.
The Importance of High-Quality Filter Nozzles
Filter nozzles sit at the bottom of sand or multimedia filters and are responsible for:
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Uniform water distribution during filtration
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Even backwash flow to expand and clean the media bed
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Preventing media loss (sand, anthracite, garnet, etc.)
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Maintaining consistent filter performance over time
Tecpro supplies ILMAP filter nozzles—renowned globally for precision engineering, accuracy and long service life.
Key nozzle features:
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Accurate slot or screen gaps to prevent media migration
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High mechanical strength for repeated backwash cycles
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Corrosion-resistant materials including PP, ABS, PVC and stainless steel
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Low pressure drop for efficient filtration
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Wide range of stem lengths to suit all filter tank designs
The right nozzle selection ensures optimal hydraulic performance and long-term filter reliability.
Applications of Sand & Gravity Filters
Sand and multimedia gravity filters are used across:
Municipal Water Treatment
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Drinking water plants
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Post-coagulation and sedimentation polishing
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Pre-treatment for disinfection and membrane systems
Wastewater Treatment
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Secondary and tertiary filtration
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Effluent polishing before discharge or reuse
Desalination
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Pre-treatment before SWRO
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High-capacity gravity filters for large plants
Industrial Water Treatment
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Cooling tower water
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Boiler make-up water
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Chemical, mining and petroleum process water
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Food & beverage rinsing and washwater recovery
Tecpro provides nozzles, spray systems and tank cleaning solutions to suit all of these applications.
Gravity Filters vs Pressure Filters
While both use sand or multimedia for filtration, they operate differently:
Gravity Filters
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Open-top design
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Water flows downward by gravity
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Ideal for large municipal plants
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High throughput with low energy consumption
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Easy access for inspection and maintenance
Pressure Filters
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Enclosed steel vessels
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Water is pushed through under pressure
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Suitable for industrial and compact plants
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Faster filtration and higher head pressure
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Easily integrates with existing pipework
Tecpro offers filter nozzles and under-drain accessories compatible with both types.
Supporting Equipment for Filter Performance
To enhance the operation of sand and gravity filters, Tecpro also supplies:
Spray Nozzles for Surface Wash
Used to break up compacted media before backwashing.
Washdown Guns & Hose Reels
For cleaning filter galleries, platforms and walkways.
Tank Cleaning Heads
For cleaning chemical tanks, washwater tanks and backwash holding tanks associated with filtration systems.
Backwash Optimization Support
Advice on flow rates, nozzle spacing and media compatibility.
Benefits of Sand & Gravity Filtration
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Proven, reliable filtration method
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Low operating and maintenance costs
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Simple and robust design
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Flexible—works with many types of media
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Suitable for high-volume water treatment
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Effective removal of turbidity and suspended solids
Combined with ILMAP’s precision nozzles and Tecpro’s engineering expertise, filtration systems operate more efficiently and with fewer issues over their lifetime.
Why Choose Tecpro Australia?
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Exclusive access to ILMAP filter nozzles—world-leading quality
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Expert guidance on nozzle selection and under-drain design
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Wide range of materials and configurations for all filter types
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Strong support for municipal, industrial and OEM customers
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Local stock, fast delivery and technical assistance
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Additional spray and washdown solutions for full system optimisation
Whether upgrading existing filters or designing a new filtration system, Tecpro delivers proven solutions that enhance performance and reliability.
