Bag filter housings – technical overview
Bag filter housings are widely used for liquid filtration applications where flexible capacity, high dirt holding and straightforward operation are required. They are commonly applied in industrial process filtration, water treatment and utility systems to remove suspended solids and protect downstream equipment.
Compared to cartridge-based filtration systems, bag filter housings offer a cost-effective solution for applications with moderate to high solids loading. Their design allows fast and simple filter bag replacement, helping to minimise downtime and simplify routine maintenance.
Filtration principle
Bag filter housings operate using replaceable filter bags that retain contaminants within the bag structure. Depending on the selected filter bag type, filtration can be based on depth filtration, surface filtration or multilayer constructions. Flow enters the housing, passes through the filter bag media and exits as filtered liquid.
As contaminants accumulate inside the filter bag, pressure drop gradually increases. The filter bag is typically replaced once the maximum allowable differential pressure is reached, ensuring stable filtration performance throughout the service cycle.
Housing configurations
- Single bag filter housings – compact housings designed for low to medium flow applications where space efficiency and simple operation are required
- Multiple bag filter housings – housings with multiple filter bags installed in parallel to accommodate higher flow rates and extend service intervals
- X100 bag filter housings – heavy-duty designs intended for applications with high dirt loads and demanding operating conditions
- PVDF bag filter housings – corrosion-resistant housings selected for aggressive chemical environments where metallic housings are not suitable
Typical applications
- Industrial process liquid filtration
- Water and wastewater treatment
- Chemical processing and surface treatment
- Protection of pumps, heat exchangers and downstream filtration stages
- Pre-filtration upstream of cartridge or membrane filtration systems
Key selection criteria
- Required flow rate and number of filter bags
- Filter bag type and filtration principle (depth, surface or multilayer)
- Housing material compatibility with the process fluid
- Operating pressure, temperature and chemical exposure
- Bag size, sealing configuration and ease of maintenance
Bag filter housings are often used as pre-filtration stages upstream of filter cartridge housings or other polishing filtration systems. This approach helps reduce particle load and extend the service life of downstream filters.