New: EMC technology also for 10 m filter bags

1 EMC test system for bag lengths of 10m

2 Pressure distribution as a function of bag length

3 Top-down gas flow supports the bag cleaning process

4 Comparison of the differential pressure of the filter as a function of bag length and dust loading

5 Size comparison of EMC filter unit for 1 000 000 Am³/h when using 6 m or 10 m filter bags

6 3D schematic of an EMC filter unit

7 Diametrically opposed configuration of the shutoff flaps during cleaning of the respective filter module

8 Significantly lower fluctuations in differential pressure of the filter during EMC mode of operation compared to offline operation

9 Ratio of the online differential pressure to that of EMC

10 Ratio of the online differential pressure to that of EMC

11 EMC process filter at the Dotternhausen cement plant Holcim GmbH

12 EMC logo

1 EMC test system for bag lengths of 10 m

Summary: On 25 April 2003 Scheuch GmbH, Aurolzmünster/Austria, was granted Austrian patent No. AT 410403 for its EMC-filter bag cleaning system (EMC: Energy-Minimizing-Concept). This was followed on 6 October 2004 by European patent No. EP 1404431. Right from the outset, this cleaning concept was oriented towards long bags (min. 8000 mm), for filter area loadings significantly higher than 1 m/min and dust loads of up to 1000 g/Am³. In addition to the known operating cost savings potential, the use of 10 m filter bags provides substantial cost benefits, not only for new plants (above 500 000 Am³/h), but particularly in the case of migration from electrostatic precipitators to bag filters and upgrades of existing bag filter units for the purpose of capacity increase.

1 Introduction

After the use of 8 m filter bags had become state of the art in the cement industry thanks to EMC technology, intensive development work resulted in the successful transfer of EMC advantages to 10 m filter bags and in verification for industrial application.

2 Technological solution

2.1 Initial situation – objective: use of 10 m filter bags

In new plant concepts, the clinker cooler exhaust gas is fed together with the kiln exhaust gas to a common filter in order to utilize synergetic effects or in order to make more recuperated heat available for the drying of very moist raw...