Improve your operation with Granular Media Filters

Underdrain systems

The underdrain system is practically the heart of each filter. It collects and drains filtered water, prevents media escape, and manages backwash flow distribution. This last function is the most complex and important. If backwash flows are distributed uniformly, the filter will make long production runs with short backwash cycles and low backwash waste.

Our underdrain systems are durable from their stainless steel construction and have impressive backwash distribution uniformity. They’re also able to manage simultaneous air and water flows without interference.

Gravity filters

SVG Filters

This filter is a compact, automatic self-backwashing gravity filter. Its internal clearwell compartment eliminates the need for external pumps, piping, valves and tanking. Its steel tank filter is enclosed and comes in either a single-cell or multiple-cell design. Backwash cycles can be triggered by headloss, a set time amount or manually.

SBW Filters
This filter is similar to the SVG Filter in most ways. It’s also self-backwashing with an internal compartment. However, it comes in a rectangular steel tank.

OTG Filters
OTG Filters are open top with downflow gravity filters. They are capable of accommodating wide variations in headloss and deep, multimedia filter beds.

Pressure filters

Vertical Pressure Filters
These pressure filters allow for versatile filtration for pressurized feed streams. They can handle deep, multimedia filter beds. Compared to gravity filters, pressure filters have higher filtration rates, solid loading and terminal losses. Our filters are fully shop-fabricated to ensure that they meet ASME Boiler and Pressure Vessel Code Section VIII.

Horizontal Pressure Filters
Just like Vertical Pressure Filters, these Horizontal Pressure Filters allow for versatile filtration of pressurized feed streams. They have a three-foot limit for bed depth, but are able to function well within that measurement. They have the same advantages when compared to gravity filters as the Vertical Pressure Filter. They come in a stainless steel vessel with abrasion-resistant rubber lining.

Reliable and thorough service

The following services come with your Granular Media Filters from FLSmidth.

On-site filter audits
If you’d like to save costs and continue using the filters your application already has installed, at FLSmidth we provide audits for current filters. We often have economical solutions for increasing your current filters’ capabilities.

Full-system supply capability
If you’re looking for an entire system design, we have thorough experience to offer. Our engineers can supply a complete system tailored to your facility.

Construction management and erection services
With these services we provide filter tank erection, system piping design and installation and control system design and start-up.

Replacement parts supply
Whenever is necessary, you can draw from the extensive supply of replacement parts that we maintain.

Control panels

When looking for outdoor control panel service, we provide NEMA control panels. For indoor purposes, we provide other ratings. If your operation prefers a simple arrangement, we can provide a single push-button control with an indicator light for backwash initiation. When it comes to multi-filter installation, isolation switches can be included in the cabinet. This allows individual cells to be taken off-line as needed. All panels are completely shop assembled and have labeled terminal strips to expedite field wiring.

Process controllers
To make processes more convenient, we can fully automate your filter operation using compact PLC control units. We pre-program these controls and install them in the control panel. If your application performs better with more complex controls, we can also provide microprocessors and distributed control systems. Using FLSmidth logic diagrams, filter control functions can also be placed on existing process control systems.

Instruments
We offer many instruments for controllers. Flow control valves come with orifice plates or flow tubes. Flow indicator controllers can be panel-mounted to interface with the process controller. Level or pressure-change control functions can be incorporated and centralized. We also offer optional flow, level or headloss gauges.

Valves
On-off service for backwash flow control is available through butterfly valves with actuated pneumatic cylinders. And positioners are available for flow modulation. You can also request electric motor actuated valves.

Skid mounting
Complete flow-control modules can be supplied with all required piping, instrumentation, valves, and controls. To ensure fast installation and start-up time, we provide these fully assembled and skid-mounted.