12–18mm Pebbles

12–18mm Pebbles Filter Media – High-Purity Silica Support Gravel for Water Treatment Plants & Industrial Multigrade Filters

The Foundation of Reliable Filtration

The 12–18mm Pebble layer is an indispensable component of any professional multi-media or pressure sand filter. Placed directly above the coarsest gravel or underdrain laterals, this specific 12–18mm grade acts as a “transition zone” that maintains the structural integrity of the filter bed even during intense backwash cycles.

Key Features & Benefits:

• Superior Flow Dynamics: The naturally rounded to sub-angular shape of these pebbles reduces friction and pressure loss, allowing water to pass through the lower layers of the tank efficiently.

• Prevents Media Migration: Carefully sized to bridge the gap between heavy base gravel and finer 2-4mm grit, ensuring that your expensive top-layer media (like activated carbon or fine sand) stays exactly where it belongs.

• Chemical Stability: Consisting of over 92% silica (SiO₂), these pebbles are chemically inert. They do not react with water treatment chemicals, ensuring the water remains safe for potable use without pH fluctuations.

• High Mechanical Strength: Unlike ordinary stones, these siliceous pebbles are dense and durable. They resist the mechanical wear caused by backwashing and air scouring, meaning they rarely need replacement over the life of the filter.

• Consistent Quality Control: Each batch is processed through rigorous washing and kiln-drying to adhere to industrial standards (like ANSI/AWWA B100), ensuring the media arrives ready for immediate installation.

Typical Applications in Sri Lanka:

• Industrial Water Treatment Plants (WTP/ETP): Essential support bedding for municipal and factory-level purification systems.

• Reverse Osmosis (RO) Pre-treatment: Acts as a stabilizing base in large-scale pre-filtration tanks to protect delicate RO membranes from silt and debris.

• Swimming Pool Systems: Used in commercial sand filters for hotels and sports complexes to manage high flow volumes.

• Borehole & Well Water Filtration: Ideal for domestic large-capacity filters where raw water contains high levels of turbidity and larger sediment.

Technical Specifications: