LEFILTER Multi-Media Filter: Layered Filtration for Clear Water—From Suspended Solids to Pre-Treatment Excellence

Introduction  

Multi-media filter is a process of using one or several filter media to pass water with higher turbidity through a certain thickness of granular or non-granular material under a certain pressure, thereby effectively removing suspended impurities and clarifying the water. Commonly used filter materials are quartz sand, anthracite, manganese sand, etc., which are mainly used for water treatment to remove turbidity, soften water, and pre-treatment of pure water.

The above figure mainly indicates the three main links of water treatment, which are mechanical fltration stage (multi-media filtration), precision filtration stage, reverse osmosis stage. Raw water passes through mechanical flters and activated carbon filters to remove suspended solids and odors, and after passing through precision filters to remove tiny particles, it enters the Reverse osmosis device to achieve the purpose of purifying water quality.

Features

• ① Graded Media: "Big Particles First, Small Ones Later"

• Anthracite (top layer): 1.2–2.0 mm particle size, low density (1.4–1.6 g/cm³). Traps large suspended solids (5–50 μm) like algae and silt, with high dirt-holding capacity.

• Quartz sand (middle layer): 0.5–1.2 mm particle size, medium density (2.6–2.7 g/cm³). Captures fine particles (1–5 μm) such as clay and rust.

• Garnet/manganese sand (bottom layer): 0.2–0.5 mm particle size, high density (4.0–4.2 g/cm³). Removes colloids (<1 μm) and, with manganese sand, oxidizes iron/manganese ions (Fe²⁺→Fe³⁺).

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• ② Auto-Backwash: Self-Cleaning Without Downtime

• Trigger modes: Time-based (e.g., every 24 hours) or pressure difference-based (when inlet-outlet pressure >0.15 MPa).

• 3-step cleaning:

• Backwash: Reverse flow (10–15 L/m²·s) lifts media, flushing trapped impurities.

• Rinse: Forward flow (5–8 L/m²·s) settles media in original layers.

• Standby: Automatically returns to filtration mode, with <5 minutes of downtime.




• ③ Durable Construction: Built for Harsh Environments

• Tank material: Optional FRP (fiberglass-reinforced plastic, corrosion-resistant for acidic/alkaline water) or carbon steel with epoxy coating (for high-pressure industrial use).

• Internal components: 316 stainless steel distributor (resists rust) and PVC lateral pipes (smooth flow, no scaling).

• Service life: Media lasts 2–3 years; tank lifespan ≥10 years (tested in coastal high-salt environments).

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Technical Drawings

Technical Parameters

• Working effect

Influent turbidity:<20FTU, effluent turbidity:<3FTU

• Working Environment Parameters

Working temperature: 5-60°C

Working pressure:0.6MPa

Water inlet pressure: > 0.1MPa

Backwash water inlet pressure:>0.3 MPa

Pressure difference between inlet and outlet: 0.02-0.05MPa

•  Operating parameters

Working method: pressure type

Operating method: water flow from top to bottom

Filtration speed: 10-20m/h

Backwashing method: water washing, or air-water combined backwashing

Backwashing water consumption:3%

Backwashing intensity: 4-15L/s-m2

Backwash duration: 10-15min

Backwash expansion rate: 40-50%

• Control mode: manual control, automatic control (time control)

• Tank material:Q235B,304,316L, carbon stel with rubber lining.Water cap material:ABS,304,316L

• Single flow rate: 0.5m3/h~180m3/h

• Input voltage: AC22OV± 10 %50-60HZ

• Output voltage: AC24V/ AC220V

• Load power: 24W/1A

• Power of each circuit:<50w

Application Fields

① Municipal Water Supply: Protecting Public Health

• Challenge: River/lake water often contains algae, silt, and organic debris (turbidity 20–100 NTU), which clog pipes and affect disinfection.

• Solution: LeFilter filters reduce turbidity to <3 NTU, ensuring chlorine disinfection works efficiently (lowering trihalomethane formation by 40%).

• Case: A municipal water plant in Hubei cut filter maintenance costs by 60% after switching to layered media.

② Industrial RO Pre-Treatment: Extending Membrane Life

• Challenge: RO membranes are easily damaged by particles >5 μm, leading to frequent cleaning and replacement (costing ¥10,000+/year for small systems).

• Solution: Multi-media filtration as pre-treatment removes 95% of particles, reducing RO cleaning frequency from monthly to quarterly.

• Data: A electronics factory using LF-MF-1200 extended RO membrane life from 2 years to 3.5 years.

③ Swimming Pools & Aquariums: Crystal-Clear Water

• Challenge: Pool water accumulates skin cells, hair, and sunscreen residues, causing cloudiness and bacterial growth.

• Solution: LeFilter’s auto-backwash filter maintains turbidity <1 NTU, reducing chlorine use by 30% (safer for swimmers).

• User Feedback: A hotel pool reported 80% fewer guest complaints about "cloudy water" after installation.

④ Mining Wastewater: Recycling Resource

• Challenge: Mine drainage contains heavy metal particles (e.g., Fe, Zn) and silt, failing discharge standards (turbidity ≤20 NTU).

• Solution: Manganese sand in the filter oxidizes Fe²⁺ to Fe³⁺, while layered media removes particles, enabling water reuse for dust suppression.

• Result: A coal mine in Shanxi recycled 80% of wastewater, saving ¥200,000/year in fresh water costs.

Q&A: Your Concerns, Answered

Q1: How to choose media combinations?

A: For general turbidity: anthracite + quartz sand + garnet. For iron/manganese-rich water: replace garnet with manganese sand. For high organic content: add activated carbon in the top layer.

Q2: How often to replace media?

A: Anthracite: 2–3 years; quartz sand: 3–4 years; manganese sand: 1–2 years (faster depletion due to iron oxidation).

Q3: Can it handle high-temperature water?

A: Yes. FRP tanks tolerate 5–60℃; for >60℃, choose carbon steel tanks with high-temperature coating.

Q4: Is manual operation difficult?

A: Basic models have simple valve controls (3 steps: filter → backwash → rinse). For large systems, automatic PLC control is recommended (set and forget).