High-Precision Tubular Filtration Technology
Candle Filtration is a premium industrial filtration technology that uses long, vertical tubular filter elements (candles) housed in a pressure vessel. It is highly effective for fine filtration, polishing, and clarification of liquids, especially in applications requiring high purity and excellent cake formation.
| Feature | Benefit |
|---|---|
| Vertical Tubular Design | Large filtration area with excellent cake formation |
| Fine Filtration | Down to 0.5 – 5 microns particle retention |
| High Pressure Operation | Handles high differential pressures effectively |
| Backwashing Capability | Automatic or manual cleaning extends filter life |
| Versatile Media Options | Stainless steel, polypropylene, ceramic & sintered metals |
| Industry | Application |
|---|---|
| Polymers & Resins | Melt filtration and catalyst recovery |
| Pharmaceuticals | Intermediate and API clarification |
| Edible Oils | Polishing and dewaxing |
| Chemicals | Fine particle removal in aggressive media |
| Parameter | Specification |
|---|---|
| Filtration Rating | 0.5 µm – 100 µm (depending on media) |
| Candle Length | 250 mm – 3000 mm (custom available) |
| Candle Diameter | 20 mm – 150 mm |
| Operating Pressure | Up to 20 bar (290 PSI) |
| Operating Temperature | Up to 250°C (depending on material) |
| Filter Media | Stainless Steel, Polypropylene, Sintered Metal, Ceramic, Glass Fiber |
| Housing Material | Stainless Steel 304 / 316L, Carbon Steel, Duplex |
| Flow Rate Capacity | From 1 m³/h to 500+ m³/h per unit |
| Particle Size (µm) | Efficiency at Low Velocity | Efficiency at High Velocity | Efficiency after 8 Hours |
|---|---|---|---|
| 0.5 – 1 µm | 92% | 78% | 65% |
| 2 – 5 µm | 98% | 91% | 85% |
| 10 – 20 µm | 99.5% | 97% | 94% |
| > 50 µm | 99.9% | 99.5% | 98% |
Key Insight: Filtration efficiency decreases with smaller particle size, higher face velocity, and longer operating time due to filter loading.
| Industry | Key Applications | Benefits |
|---|---|---|
| Polymers & Plastics | Melt filtration, catalyst recovery, polymer solution polishing | High temperature resistance and fine particle removal |
| Pharmaceuticals | API clarification, intermediate filtration, sterile solutions | High purity and easy validation |
| Edible Oils & Fats | Dewaxing, bleaching earth removal, final polishing | Excellent clarity and extended shelf life |
| Chemicals | Aggressive solvents, acids, catalyst recovery | Corrosion resistance and long service life |
| Beverages & Food | Juice clarification, beer, wine, syrup polishing | High flow rates and easy cleaning |
| Water Treatment | Process water, wastewater, condensate polishing | Reliable fine filtration with automatic backwash |
| Question | Answer |
|---|---|
| What is a Candle Filter? | A Candle Filter is a vertical tubular filtration system where liquid flows through long cylindrical filter elements (candles) to remove fine particles. |
| What is the typical filtration rating? | Candle filters can achieve fine filtration from 0.5 µm to 100 µm, depending on the filter media used. |
| Can candle filters be cleaned automatically? | Yes. Many systems offer automatic backwashing or vibration cleaning for continuous operation with minimal downtime. |
| What materials are used for candle filters? | Stainless steel, polypropylene, sintered metal, ceramic, and glass fiber are commonly used. |
| What industries use candle filtration? | Polymers, pharmaceuticals, edible oils, chemicals, beverages, and water treatment. |
| What are the main advantages? | High dirt holding capacity, excellent cake formation, high temperature & pressure resistance, and low maintenance. |
| Step | Installation Procedure | Important Notes |
|---|---|---|
| 1 | Select a stable, level location with sufficient clearance for maintenance and candle removal. | Allow at least 1.5× candle length above the vessel. |
| 2 | Install the filter vessel using proper foundation bolts. Ensure it is perfectly vertical using a spirit level. | Misalignment can cause uneven flow and premature failure. |
| 3 | Connect inlet, outlet, vent, and drain lines with proper gaskets and supports. | Use flexible joints to reduce stress on the vessel. |
| 4 | Carefully insert clean candle elements into the tube sheet. Ensure proper seating and O-ring sealing. | Avoid damaging the candles during installation. |
| 5 | Install the top cover and tighten bolts in a criss-cross pattern to the recommended torque. | Check torque values in the manual. |
| 6 | Connect compressed air or backwash lines (if equipped) and slowly pressurize the system while checking for leaks. | Never exceed design pressure. |
| 7 | Perform a test run and verify flow rate, pressure drop, and proper operation. | Record baseline pressure readings for future reference. |
| Step | Maintenance Procedure | Important Notes |
|---|---|---|
| 1 | Depressurize the system completely and isolate the filter vessel before any maintenance. | Always follow Lockout/Tagout procedures. |
| 2 | Drain the vessel completely from the bottom drain valve. | Collect and dispose of slurry properly. |
| 3 | Open the top cover and carefully remove the candle elements one by one. | Use proper lifting tools to avoid damage. |
| 4 | Clean the candles using water, compressed air, or appropriate solvent. Backwash if equipped. | Inspect for damage or excessive wear. |
| 5 | Inspect O-rings, gaskets, and tube sheet seals. Replace if worn or hardened. | Use compatible gasket materials. |
| 6 | Reinstall clean candles, close the cover, and tighten bolts in a criss-cross pattern. | Follow manufacturer torque specifications. |
| 7 | Slowly repressurize the system and monitor pressure drop and flow rate. | Record maintenance details in the logbook. |