High Dust Holding Cartridges — 3× Longer Life, A Game Changer for Mixing Plant Dust Control

Key Selling Points at a Glance

· 2–3× Extended Service Life — 14 to 32 working days versus 7–15 days for conventional 

cartridges

· 70%–130% Higher Dust Holding Capacity — 600–800g/m² gradient density substrate

· PTFE Microporous Membrane Surface Filtration — Dust release rate ≥93%, resistance 

recovery rate exceeds 90%

· Hydrolysis-Resistant, Alkali-Tolerant, Anti-Hardening — Specifically engineered for cement 

dust conditions

· Wide-Shallow Bridge-Proof Pleat Design + Reinforced Cage — Eliminates dead zones and

 structural deformation

I. Operating Condition Background and Design Objectives

During cement silo feeding, aggregate unloading, mixer discharge, and powder tanker

 unloading in concrete mixing plants, high-concentration composite dust is generated,

 with inlet dust concentrations reaching 120–180g/m³. The dust exhibits four typical 

operating condition characteristics:

· Particle size distribution: predominantly concentrated in the 1–20μm range

· Chemical properties: contains calcium hydroxide, weakly alkaline

· Hygroscopicity: prone to moisture absorption and hardening under fluctuating air humidity

· Abrasiveness: mixed with fine sand and stone particles, exhibiting certain abrasive properties

These conditions impose severe challenges on installed filter cartridges. Conventional 

standard polyester thin cartridges (480–500g/m² single-layer structure) are susceptible

 to four types of aging failure under continuous high ash load:

· Rapid resistance rise — fine dust penetrates into the fiber interior

· Incomplete cleaning — pulse cleaning cannot fully remove hardened ash layers

· Scouring wear — hard particles continuously erode the filter media

· Alkaline degradation — long-term exposure to alkaline media reduces fiber strength

The service cycle of conventional cartridges is only 7–15 working days. Frequent replacement 

affects continuous equipment operation and significantly increases on-site operation and

 maintenance costs. To address these challenges, we introduce our High Dust Holding Capacity 

Long-Life Filter Cartridges — engineered through material upgrades and structural optimization

 for stable, long-term performance.

II. Filter Media Grading Parameters and High Dust Holding Technical Principles

All filter media performances comply with GB/T 6719 national standards, adopting a gradient 

density thickened substrate + PTFE microporous membrane composite structure. Based on 

dust concentration and ambient humidity of mixing plants, the filter media are divided into

 three adaptation grades.

Grade 1 — Medium Ash Load General Type (600g/m² Gradient PET + Thin PTFE Membrane)

Structural composition: Three-layer gradient polyester fiber construction — outer loose buffer 

layer, intermediate dust storage transition layer, and inner precision filtration layer. Surface is

 thermally laminated with PTFE membrane and calendered for hydrophobic treatment.

Core technical parameters:

· Unit dust holding capacity: 1450–1650g/m² — 70% higher than standard 500g media

· Alkaline adaptability: pH 8–13, tensile strength retention ≥86% after 800 hours of alkaline 

dust aging

· Continuous operating temperature: ≤120°C

· Filtration accuracy: 0.3μm, surface filtration prevents dust penetration into fiber interior

Applicable conditions: Single-line small mixing plants, single cement silo dust removal, inlet

 concentration ≤120g/m³, ambient relative humidity ≤70%

Standard service cycle: 25–32 working days under standardized operation and maintenance 

conditions

Grade 2 — High Ash Load Mainstream Type (700g/m² Reinforced Gradient PET + Thickened PTFE

 Membrane)

Structural composition: Four-layer high-density gradient polyester substrate with double-sided 

polished thickened PTFE membrane. The substrate is blended with anti-static fibers to improve 

fine dust release performance.

Core technical parameters:

· Unit dust holding capacity: 1700–1950g/m² — 105% higher than conventional thin cartridges

· Enhanced abrasion and scouring resistance, adapted to sand/stone particle impact at 

discharge points

· Humidity adaptation range: ≤85% RH

· Conventional pulse cleaning dust release rate: ≥93%, resistant to hard compaction formation

Applicable conditions: Double-line medium-sized mixing plants, multi-silo simultaneous feeding, 

dust concentration 120–160g/m³, semi-open plants with occasional condensation in rainy 

seasons

Standard service cycle: 18–26 working days under standardized operation and maintenance 

conditions

Grade 3 — Ultra-High Ash Load Heavy-Duty Type (800g/m² Ultra-Thick Gradient PET + Mirror 

PTFE 

Membrane)

Structural composition: Multi-layer thickened buffer fiber substrate with fluorinated high-density

 PTFE isolation membrane, plus overall hydrolysis-resistant impregnation treatment.

Core technical parameters:

· Unit dust holding capacity: 2000–2300g/m² — 130% higher than conventional cartridges

· Strength retention: ≥92% after 1200 hours of alternating high/low temperature and high ash

 load aging test

· Membrane peel strength: ≥38N/5cm

· Humidity adaptation range: 85%–98% RH, inhibits dust mud hardening caused by

 condensation

Applicable conditions: Three-line large mixing plants, simultaneous operation of multiple 

aggregate bins and multiple cement silos, instantaneous peak dust concentration >160g/m³, 

coastal high-humidity plant conditions

Standard service cycle: 14–22 working days under standardized operation and maintenance

 conditions

Membrane Dust Holding Stability — Core Parameters

The PTFE membrane is the critical structure enabling recyclable dust holding and long-term 

cleanability. Its low surface energy ensures dust only accumulates on the cartridge surface, 

with over 90% of original dust storage space restored after each pulse cleaning.

· Membrane thickness deviation: ≤±0.05μm, preventing dust penetration through local weak

 points

· Entire process employs thermal lamination technology without adhesive gaps, preventing

 delamination and dust leakage under alternating temperature and humidity conditions

Filter Media Performance Degradation — Judgment Criteria

The cartridge is deemed degraded and requires replacement upon occurrence of any of the 

following:

· Resistance increases by more than 100Pa per shift and cannot return to normal range after

 cleaning

· Fiber strength retention falls below 75% after alkaline dust aging, with media prone to 

scouring damage

· Filter media surface hydrophobic angle drops below 95°, resulting in continuous unpeelable 

dust compaction

III. Optimized Structural Design for High Dust Holding Cartridges

Thickened filter media must be matched with appropriate pleat and support structures;

 otherwise, dust accumulation dead zones and structural deformation will occur, preventing

 full utilization of high dust holding performance. Mixing plant dedicated cartridges adopt a 

wide-shallow bridge-proof structure design.

Dust Accumulation Proof Pleat Structure — Standard Parameters

· Pleat spacing: ≥10mm — avoids dust bridging problems common in narrow pleat structures

· Pleats per meter height: 20–26 pleats

· Pleat depth: 32–38mm — prevents uncleanable dust accumulation at deep pleat bottoms

· Pleat top angle: 55°–65° obtuse angle design — eliminates dead-angle dust accumulation

· Preferred specifications: φ325×900mm and φ350×1000mm conventional large diameters, 

with effective filtration area per cartridge reaching 16–18m²

Deformation-Resistant Thickened Support Cage

Standard 0.6–0.8mm thin cages are prone to inward concave deformation under high resistance

 conditions, compressing pleat space and reducing dust storage volume. Unified standards for 

cages under high ash load conditions:

· Wall thickness: ≥1.2mm seamless rolled perforated cage — eliminates welding gap corrosion 

risks

· Aperture: 3–4mm uniformly distributed — balances air permeability with structural strength, 

prevents unilateral abrasion from localized airflow concentration

· Material: 304 stainless steel for conventional plants; 316L stainless steel for coastal

 high-humidity plants — avoids secondary filter media contamination from rust debris

Sealing and Bonding — Adaptation Parameters

· Seals: Food-grade silicone for conventional dry-wet alternating plants — temperature 

range -30°C~180°C, resists alkaline condensate immersion. Fluororubber seals for 

high-temperature steam conditions — prevents aging expansion and dust leakage.

· End cap bonding: High-temperature fluorine-containing epoxy hot-melt adhesive with peel 

strength ≥48N/cm — does not hydrolyze or debond in high-humidity alkaline environments, 

preventing local cartridge overload from bypass dust leakage

IV. Front-End Pre-Separation Supporting System

Instantaneous peak ash load is the primary cause of rapid cartridge saturation. The front-end 

two-stage pre-separation structure intercepts large-particle sand/stone and coarse cement 

dust in advance, reducing overall cartridge load by 50%–70% and fully utilizing long-term dust 

holding performance.

Stage 1 — Labyrinth Coarse Dust Baffle

A stainless steel labyrinth dust retaining structure installed at the equipment air inlet intercepts

 coarse sand and stone particles above 30μm, preventing hard particles from directly scouring 

and wearing the membrane. Accumulated coarse dust on the baffle is cleaned per shift to prevent

 secondary dust from entering the cartridge zone.

Stage 2 — Mini Cyclone Pre-Separation Device

Large multi-line mixing plants can be equipped with a front-mounted mini cyclone separator to

 pre-separate 60%–80% of large-particle dust, reducing inlet dust concentration from 180g/m³ to

 below 80g/m³ — effectively lowering cleaning frequency and wear load, thereby extending 

service life.

Auxiliary Source Dust Suppression Measures

· Dry fog dust suppression devices at aggregate discharge and silo top feeding points — reduces 

dust generation at source

· Optimized negative pressure balance during tanker unloading — avoids instantaneous 

overpressure dust emission

· Proper raw material moistening with moisture content controlled at 6%–8% — reduces 

fugitive dust without compromising production quality

V. System Operating Parameter Control

Improper control of filtration air velocity, cleaning parameters, and cabinet condensation will 

cause 30%–50% performance loss of thickened filter cartridges. Graded parameter standards

 shall be strictly implemented.

Filtration Air Velocity — Graded Control Standards

· Medium ash load, single-line (≤120g/m³): air velocity 0.5–0.6m/min with 10% air volume 

margin

· High ash load, double-line (120–160g/m³): air velocity 0.4–0.5m/min with 20% air volume 

margin

· Ultra-high ash load, multi-line (>160g/m³): air velocity ≤0.35m/min with 30% air volume 

margin

⚠️ Excessive air velocity will compact alkaline dust into irreversible hard layers, drastically 

shortening cartridge service life.

Differential Pressure Linked Pulse Cleaning — Parameter Optimization

Adopt frequent, gentle cleaning instead of long-interval centralized high-pressure cleaning to 

prevent dust compaction and solidification.

Air source requirements: Must be equipped with a refrigerated dryer and two-stage oil-water 

separator — air source dew point ≤-20°C, residual oil ≤0.1ppm. Oil- and water-containing air

 sources will form oil-dust mixtures and permanently block filter media pores.

Graded cleaning pressure:

· Medium ash load: 0.40–0.45MPa, single injection duration 0.18–0.20s

· High ash load: 0.45–0.55MPa, single injection duration 0.20–0.25s

Insufficient pressure results in incomplete cleaning; excessive pressure wears the membrane.

Intelligent linkage logic:

· Resistance below 800Pa: cleaning interval 10–15min

· Resistance 800–1000Pa: automatically shortens to 5–8min

· Resistance above 1000Pa: initiates forced continuous cleaning to avoid long-term 

high-resistance dust compaction

Equipment resistance warning value: 1000Pa (inspection triggered)

Replacement threshold: 1500Pa

VI. Standardized Daily Operation and Maintenance Specifications

1. Record equipment operating resistance per shift. In case of abnormal resistance rise within a

 single shift, promptly inspect the cleaning system and pre-separation device.

2. Clean front-end dust retaining structure daily. Regularly empty the ash hopper to avoid 

overload caused by secondary dust emission.

3. Inspect compressed air oil-water separator weekly. Drain sewage promptly to ensure dry and

 oil-free air source.

4. Prohibited operations:

   · ❌ High-pressure external flushing of cartridges — damages membrane

   · ❌ Water or chemical soaking of cartridges — cement dust solidifies with water

   · ❌ Mechanical beating of cartridges — damages filter media structure and membrane

   · ✅ Slight blockage: allow only 2 times or less of low-pressure (0.2MPa) internal back-flushing 

as emergency treatment — repeated cleaning accelerates media aging

5. Seasonal adjustment: When plant humidity rises during rainy seasons, appropriately reduce 

system air volume, lower filtration air velocity, and shorten cleaning intervals to reduce sticky

 dust compaction risk.

VII. Common Fault Analysis and Solutions

Fault 1 — Short service cycle and rapid resistance surge of thickened high dust holding cartridges

Core causes:

· Excessive filtration air velocity

· Missing or damaged front-end pre-separation structure

· Insufficient cleaning pressure and excessive cleaning interval leading to dust compaction

Solutions:

· Expand filtration area by adding cartridges to reduce air velocity to standard range

· Repair and reinforce front dust retaining structure with regular cleaning and discharge

· Adjust pulse pressure and cleaning cycle; enable differential pressure linked intelligent 

cleaning mode

Fault 2 — Uneven resistance rise across batch cartridges and rapid local saturation

Core causes:

· Irregular cartridge pleat spacing

· Cage deformation compressing dust storage space

· Uneven airflow distribution inside cabinet causing local overload

Solutions:

· Replace with standard wide-shallow pleat structure cartridges

· Uniformly replace with thickened stainless steel deformation-resistant cages

· Adjust cabinet deflector to balance airflow load across all cartridges

Fault 3 — Mud accumulation at pleat bottoms during rainy seasons with unremovable dust after 

cleaning

Core causes:

· No thermal insulation or heat tracing on cabinet, severe wall condensation

· Horizontal cartridge installation leading to water and mud accumulation

Solutions:

· Install cabinet thermal insulation and electric heat tracing to ensure operating temperature

 remains above dew point

· Adopt vertical installation orientation

· Shorten cleaning intervals during rainy seasons to remove damp dust in a timely manner