How EMW®-Pulsfilter with Poret®-Wrap reduce differential pressure and extend service life.
At a site in Central America two gas turbines of the GE 7F 5-Series type are in operation. During operation, there were increasing strong rises in differential pressure (Δp), resulting in power losses, increased fuel consumption and unplanned turbine shutdowns.
The existing pulse filters exhibited inconsistent pleat geometry. Due to the instability of the Pleat-Lock technology the pleat packs compressed during operation – the active filter area decreased, flow resistance increased and Δp peaks rose.
Solution: In a comparative study EMW® Pulse Filters with an innovative stabilized pleat technology in combination with the pulsable Poret® Wrap were used. In operation one unit was equipped with the EMW® combined pulse filters and the other unit with pulse filters using the so-called Pleat-Lock technology.
• AQI often in the moderate range
• Frequently elevated PM₁₀ levels, which can rise to 2 to 5 times normal values; 24-h average of PM₁₀ up to approx. 197 µg/m³
The EMW® Pulse Filters impress with a revolutionary pleat design that offers maximum stability of the filter media.

The interior of the EMW® Pulse Filter still shows an intact pleat structure even after use, thereby ensuring minimal development of differential pressure during operation.

Opening a pleat of the EMW® Pulse Filter reveals the well-thought-out media structure. The innovative design allows a full utilisation of the filter area, which leads to a significantly extended service life of the EMW® pulse filter.

EMW® Pleat Technology: Ensures a permanently stable pleat pattern, uniform media utilisation and reduced increase of differential pressure.
Poret® Wrap: A pulsable, unique pre-filter media for pulse filters with increased dust storage capacity
| Pulse filter | Pulse filter with Pleat-Lock technology | EMW® Pulse Filter with Poret® Wrap | |
|---|---|---|---|
| Average Δp | 2,524 mbar | 1,896 mbar | |
| Maximum Δp | 5,377 mbar | 3,774 mbar | |
| Share Δp ≤ 2,5 mbar | 44,2 % | 98,7 % |
EMW® Pulse Filters demonstrate the more robust peak-load performance and spend significantly more operating time in a low differential pressure range. This is an indicator of fewer pulse cycles and an extended operating period to stabilise the power plant operation of the gas turbines.
• Increased availability & output: reduced Δp peaks mitigate the risk of load reductions/down-regulations.
• Lower OPEX drivers: potentially fewer pulse cycles, longer operational intervals until filter change.
• Higher operational safety: a more stable Δp curve enables plannable maintenance intervals.
• Lower peaks: Δp EMW 2.235 mbar vs. 3.019 mbar (Pleat-Lock).
• Fewer outliers: Max Δp EMW 3.774 mbar vs. 5.377 mbar.
• Share Δp ≤ 2.5 mbar: EMW 98.7% vs. 44.2% (Pleat-Lock).
The combination of the innovative pleat technology of EMW® Pulse Filters and the pulsable pre-filter media Poret® Wrap delivers a more stable differential pressure, lower operating costs and a longer service life of the filters – thereby making a measurable contribution to operational safety and plant efficiency.