Comparison of Flat Panel to MiniPanel™ Diffuser

The EDI MiniPanel is a curved panel diffuser designed to save energy while maintaining high oxygen transfer efficiency. Its shape lowers the pressure needed to operate, which helps reduce energy costs when compared to traditional flat panel diffusers. 

By developing the MiniPanel diffuser EDI generated benefits and advantages versus the flat panel type diffusers:

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.

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 the effects of stress while 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.

EDI’s MiniPanel diffusers are mounted 0.2 to 0.5 meters above the floor, unlike flat panel diffusers. MiniPanels’ curved surface is easily able to shed solids, and their discrete spacing between the individual diffuser units allow solids to pass by easily when the air is turned off, and they do not accumulate at all during mixing activities. This prevents accumulation of heavy solids and operational issues like fouling and clogging without flexing

Heat Resistance

Flat panel membranes are not ideal for high-heat applications because they can experience mechanical stress, especially hoop stress, which can weaken the membrane material. Their manufacturers often warn against using them in extreme temperatures, like deep tank operations or hot processes, and require cooling of the air ahead of the diffuser systems. In contrast, EDI’s MiniPanel diffusers can handle over 215°F (100°C) without requiring air cooling, making them a better choice for heat-intensive environments..

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.

MiniPanel diffuser units can be controlled with individual orifices (for total piping and distribution) and with an engineered opening in the membrane itself (for air distributed over the surface of the membrane).

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 configuration.

Using the EDI MiniPanel system 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, the 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 diffuser systems 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).