Multi Bag Filter Housing
Multi Bag Filter Housing System
Multi bag filter housings are high-capacity pressure vessels designed to hold multiple replaceable filter bags simultaneously, providing significantly higher flow rates and solids holding capacity than single-bag models. Liquid enters the housing, flows through several bags in parallel (capturing particles inside each bag), and exits as clarified filtrate. These housings are ideal for continuous or high-volume processes where extended run times between bag changes, reduced downtime, and cost-effective operation are essential. Common applications include chemicals, paints & coatings, food & beverage, water treatment, pharmaceuticals, and large-scale industrial filtration.
System Design & Key Components
Multi bag filter housings feature a larger cylindrical or rectangular pressure vessel with multiple perforated stainless steel support baskets arranged inside. Each basket holds one filter bag, allowing parallel filtration. Bags are sealed at the top with snap-bands, O-rings, or flange rings. Liquid typically enters above the bags, flows downward through them, and exits via a common bottom or side outlet. Housings are built from stainless steel, carbon steel, or high-grade plastic with quick-access closures (swing bolts, eye bolts, or clamp lids) for fast bag changes.
Filtration & Maintenance Process
Operators typically follow this sequence for multi bag filter housings:
- Setup — Clean the housing, insert fresh filter bags into each basket, seal securely, close the lid, and vent trapped air.
- Operation — Pump liquid under pressure (typically 2–10 bar); flow divides across multiple bags, capturing solids while filtrate exits.
- Monitoring — Watch differential pressure. When ΔP reaches 1–2 bar — or visual inspection shows heavy loading — prepare for bag replacement.
- Bag Replacement — Depressurize, open lid, remove used bags (using handles/rings), dispose or clean if reusable, and install new bags.
- Restart — Secure lid, vent air, and resume flow. Change-out usually takes 10–20 minutes (longer than single-bag due to multiple bags).
Comparisons
| Feature | Multi Bag Housing | Single Bag Housing |
|---|---|---|
| Flow Capacity | High (50–500+ m³/h depending on bag count) | Low to moderate (5–50 m³/h typical) |
| Footprint & Space | Larger (multiple bags in one vessel) | Very compact |
| Change-Out Time | Moderate (10–20 minutes) | Very fast (5–10 minutes) |
| Cost (Housing + Bags) | Higher initial cost, but lower per-flow cost | Lowest initial cost |
| Best Suited For | High-flow continuous processes | Small systems, pilot plants, batch processes |
| Maintenance Frequency | Less frequent per bag due to higher total capacity | More frequent bag changes |
| Feature | Multi Bag Housing | Cartridge Filter Housing |
|---|---|---|
| Filtration Mechanism | Depth filtration (solids trapped inside bags) | Surface or depth (pleated or wound cartridges) |
| Solids Holding Capacity | Very high (multiple large bags) | Moderate to high (especially pleated designs) |
| Change-Out Time | Moderate (10–20 minutes) | Moderate (10–20 minutes for multi-cartridge) |
| Cost per Change-Out | Low (bags are inexpensive) | Higher (cartridges cost more) |
| Best Suited For | High solids loading, high-flow applications | Fine filtration, polishing, low-solids streams |
| Typical Micron Rating | 1–200 μm | 0.2–100 μm |
Typical Operating Parameters
| Parameter | Typical Range | Notes |
|---|---|---|
| Micron Rating | 1–200 μm (nominal) | Depends on bag material and construction |
| Operating Pressure | 2–10 bar (30–150 psi) | Maximum recommended ΔP usually 1.5–2.5 bar |
| Flow Rate | 50–500+ m³/h (depending on number of bags) | Scales with bag count (4–12 common) |
| Recommended Change-Out ΔP | 0.8–2 bar | Follow manufacturer guidelines |
| Temperature Range | 0–150 °C | Limited by bag material (polypropylene, polyester, nylon, PTFE, etc.) |
Common Applications & Advantages
| Industry / Application | Typical Fluid | Primary Goal |
|---|---|---|
| Chemicals & Coatings | Resins, solvents, paints, inks | Particle removal, product clarity |
| Food & Beverage | Syrups, juices, edible oils, beverages | Clarification, high-volume solids control |
| Water Treatment | Process water, cooling water, rinse water | High-flow equipment protection |
| Pharmaceuticals | Intermediates, buffers, process liquids | Pre-filtration for large batches |
| Industrial Processes | Cutting fluids, wash water, lubricants | High-throughput fluid reuse |
Key Advantages of Multi Bag Filter Housings
- High flow capacity — ideal for continuous, large-volume processes
- Extended run times between bag changes due to multiple bags
- Lower cost per unit of flow compared to multiple single-bag units
- Compact single vessel design for high throughput
- Reliable performance for moderate to high solids loading
- Scalable — add more bags for increased capacity
Also check out, "Single Filter Housing"