Comparison of Flat Panel to MiniPanel Diffuser

EDI recognizes that panel diffusers have high efficiency. With this in mind we have created Mini-Panel devices as alternatives to the flat panel diffuser types to have with the oxygen transfer efficiencies of flat panel configuration while producing actual energy savings because of significant reductions in operating pressure requirements.

mini panel 1

By developing the MiniPanel device EDI generated benefits and advantages versus the flat panel type devices:

Total energy value – The EDI MiniPanel is able to deliver significant energy benefits because it is able to deliver similar oxygen transfer efficiencies of “flat panels” with an operating pressure that is less than the operating pressure of flat panel devices!  The design minimizes the pressure losses required to distribute air in the piping network and across the surface of the diffuser membrane.

Engineering Note: EDI MiniPanel units are approximately 0.236 m2 of active surface area in a configuration of approximately 120 millimeters in diameter x 1400 millimeters long perforated top
surface only, i.e. panel configuration.

The operating pressure savings versus flat panels amounts to as much as 15 to 20% of the total operating pressure in the system.

MiniPanel Systems deliver lower total energy cost in most applications

EDI MiniPanel units are mounted on 4″ and 8″ pipe which help control the operating pressure in the system. Air pipe sizes are chosen to deliver minimum pressure loss for the operation of the system and are not fixed to a size limitation of the flat panel type of devices.

Operational stress is a critical item in any aeration membrane. The flat panel is vulnerable to high stress, internally and at any retainers or edges. By comparison the EDI MiniPanel is designed as a tubular device in order to take full advantage of low internal hoop stress. These reduced operating stresses assure long life and operational benefits.

“Flat Panels” claim beneficial geometry because membrane surface is supposedly flat during operation with uniform pressure across the entire surface.

    • “Flat panels” are flat when not in operation.
    • “Flat panels” in operation deflect upwards.
    • “Flat panels” deflection creates a similar shape segment in the total diffuser as an EDI MiniPanel.
    • Deflection of “Flat Panels” demonstrates effects of stress while the MiniPanels maintain their original shape with little deflection because of low “Hoop Stress”.

No Flexing Required

With flat panels, routine flexing and increased flux rates rates are generated in order to try and prevent excess solids from accumulating and settling on the surface of the membrane.

By comparison, the EDI MiniPanel is mounted 0.2 to 0.5 meters above the floor. The MiniPanel has a curved surface that is easily capable of shedding solids and the MiniPanels have discrete spacing between the individual units in order to allow the solids to pass by the diffusers when air is turned off. This prevents the accumulation of heavy solids and/or operational issues of fouling and clogging of the MiniPanel; no flexing required. For mixing activities solids do not accumulate under or around or between the MiniPanel devices.Panel-Test-1

Heat resistance
Flat panel membranes are typically constructed as materials that offer specific warnings against use in high heat applications. This high heat can be from deep tank operation requiring cooling of the air ahead of the diffuser system or in hot process applications. Limitations of these devices are documented in the manufacturer’s literature and become a limiting factor in many applications; particularly because of the high stress effects on warm membrane materials.

 

Heat resistance

Flat panel membranes are typically constructed as materials that offer specific warnings against use in high heat applications. This high heat can be from deep tank operation requiring cooling of the air ahead of the diffuser system or in hot process applications. Limitations of these devices are documented in the manufacturer’s literature and become a limiting factor in many applications; particularly because of the high stress effects on warm membrane materials.

 

Air flow ranges

The flat panel type devices are limited to low air flow rates in order to get proper distribution and utilization of the surface of the membrane.

By comparison the use of MiniPanel type devices can be controlled with individual orifices for total piping air distribution and the air distributed over the surface of the membrane with an engineered opening in the membrane itself.

 

Membranes

EDI membranes are designed to allow changing in less than two minutes per membrane.

 

Retrievable Option

EDI MiniPanel units are designed to allow easy application of retrievable diffuser systems. Retrievable diffuser systems can be advantageous in difficult applications and the MiniPanel is well suited to an engineered retrievable solution.

Using the EDI MiniPanel device allows access to the basin for cleaning and/or maintenance by walking between rows of diffuser units and working between those diffuser assemblies. By comparison a high floor coverage of flat panels prevents access for inspection, maintenance and/or any mechanical activity in the basin.

EDI MiniPanel units can be mounted on any type of a pipe, plastic or metal. These choices of materials are an engineering benefit for use by the engineer or owner.

By comparison, flat panel type of devices are limited to feeding with flexible hose connections in most applications or are limited to one type of piping for the installation.

 

For operation maintenance and overall system flexibility, the MiniPanel system offers high operating efficiency with low total cost of ownership (capital cost, energy cost, operation and maintenance costs as a net present value (NPV) or net present worth (NPW) evaluation).