Methods and sensors for the detection of active carbon filters degradation with EMIS-ECIS PWAS

摘要

Active carbon filters and systems that are operative to detect active carbon filter degradations are provided. The active carbon filter can include a carbon filter comprising activated carbon and defining a filter surface; a first piezoelectric wafer active sensor on the filter surface that is electrically isolated from the carbon filter; and a second piezoelectric wafer active sensor on the filter surface that is electrically connected to the filter surface; and an impedance monitoring device electrically connected to the first piezoelectric wafer active sensor and the second piezoelectric wafer active sensor. Methods are also disclosed for determining if any degradation has occurred in an active carbon filter.

主权项

1. A method of assessing filter degradation status of an activated carbon filter, wherein a plurality of piezoelectric wafer active sensors are positioned on the activated carbon filter, the method comprising:
measuring impedance spectra of pristine status at selected frequencies based on a selected methodology; saving pristine spectra data in said signal processor as baseline data; measuring impedance spectra of said piezoelectric wafer active sensors at desired intervals; storing the impedance spectra in the signal processor; and analyzing the measured impedance spectra using the selected methodology and compare with the said baseline data to estimate the degradation status of said filter, wherein the active carbon filter comprises a carbon filter comprising activated carbon and defining a filter surface, and wherein the plurality of piezoelectric wafer active sensors comprise:
a first piezoelectric wafer active sensor on the filter surface, wherein the first piezoelectric wafer active sensor is electrically isolated from the carbon filter;a second piezoelectric wafer active sensor on the filter surface, wherein the second piezoelectric wafer active sensor is electrically connected to the filter surface.