Automatic quartz sand filtration equipment

Automatic Quartz Sand Filtration Equipment | Fully Automatic Backwashing · Highly Effective Removal of Suspended Solids

This equipment uses high-quality quartz sand as the filter medium, and is equipped with a fully automatic multi-way valve or pneumatic/electric valve assembly to achieve fully automatic "filtration-backwash-forward wash" cycle operation. When the filter layer becomes saturated with contaminants, causing an increase in the inlet and outlet water pressure difference, or when a set time is reached, the equipment automatically starts backwashing to discharge the trapped impurities and restore filtration capacity. The equipment requires no manual operation, is easy to use, and produces low effluent turbidity, making it an ideal pretreatment or bypass filtration device in water treatment systems. It is widely used in cooling circulating water, swimming pools, farmland irrigation, groundwater silt removal, and greywater reuse.

core components

Automatic Control Valve: Fully automatic multi-way valve (time/differential pressure dual control type) or integrated pneumatic/electric butterfly valve assembly, with built-in PLC program, automatically switching between filtration, backwashing, forward washing, and sewage discharge stations.

Filter Tank: Vertical tank made of carbon steel with epoxy anti-corrosion coating, stainless steel 304/316L, or fiberglass, pressure resistant 0.6-1.0MPa.

Quartz Sand Filter Media: Selected natural quartz sand, multi-layered particle size distribution (0.5-4mm), large dirt-holding capacity, effluent turbidity ≤3 NTU.

Water Distribution and Collection System: Upper claw-type water distributor, lower perforated plate + filter cap or double-layer water collection device, ensuring uniform water flow distribution and no flow deviation.

Pipeline System: Equipped with manual butterfly valve, sampling valve, pressure gauge, air vent valve, and sewage discharge port.

Electrical Control Box: Remote/local switching possible, supports fault alarm output.

Working principle

Filtration: Raw water enters the tank through a control valve (or multi-way valve) and is evenly distributed on the quartz sand layer by a water distributor. The water flows downwards through the filter layer, where suspended solids are intercepted and adsorbed by the sand particles. The clean water returns to the outlet pipe through the bottom collection device.

Backwash: When the pressure differential reaches the set value or the timer is triggered, the control valve automatically switches to backwash mode: water flows upwards into the tank, causing the quartz sand layer to expand and rub against each other, stripping away trapped solids, which are then discharged from the drain with the backwash water.

Forward Wash: After backwashing, the control valve switches to forward wash mode, where a small amount of water washes the filter layer from top to bottom, recompacting the filter media and washing away residual impurities. The system then automatically returns to filtration mode. The entire process requires no manual operation.

Main advantages

Fully Automatic Operation: No dedicated personnel required; automatic backwashing based on set time or pressure differential reduces labor costs.

High Filtration Efficiency: Multi-layered quartz sand achieves a suspended solids removal rate of ≥85%.

Uninterrupted Water Supply: Can be configured with dual tanks in parallel/series during backwashing; one tank backwashes while the other continues filtration.

Robust and Durable: Tank material is suitable for corrosive water quality; quartz sand has a lifespan of 2-5 years.

Simple Maintenance: Top manhole facilitates inspection and filter media addition; standard pipe connections ensure easy connection.

Water and Energy Saving: Low backwash wastewater flow rate allows for recycling back to the raw water tank.

Technical parameters

Processing flow rate: 1 – 200 m³/h (single tank, multiple tanks can be connected in parallel)

Working pressure: 0.2 – 0.8 MPa

Design pressure: 1.0 MPa

Filtration velocity: 8 – 15 m/h (economic flow rate)

Backwash intensity: 12 – 15 L/(s·m²)

Quartz sand layer height: 600 – 1200 mm

Control method: Time-based/differential pressure-based/flow-based (selectable)

Tank material: Carbon steel epoxy/Stainless steel 304/316L/FRP

Valve configuration: Automatic multi-way valve or pneumatic/electric butterfly valve assembly

Application areas

Industrial water filtration

Swimming pool circulating water filtration (ensuring clear water quality)

Waterworks and rural safe drinking water pretreatment

Groundwater silt removal and color treatment

Primary filtration for greywater reuse and rainwater harvesting

Agricultural irrigation water purification

We can provide single-tank or multi-tank solutions, valve selection, and filter media gradation based on your influent and effluent water quality, flow rate, and site conditions. Welcome to provide parameters for customized solutions.