Gas separation: processes – With control responsive to sensed condition – Concentration sensed
Reexamination Certificate
2011-01-25
2011-01-25
Hill, Jr., Robert J (Department: 1776)
Gas separation: processes
With control responsive to sensed condition
Concentration sensed
C095S025000, C096S018000, C096S026000, C096S109000, C096S111000, C096S117000, C096S417000, C055SDIG034, C073S001060
Reexamination Certificate
active
07875100
ABSTRACT:
A method is provided for indicating the useful service life of a gas filtration and purification system comprising steps of embedding two or more mass-responsive electronic sensors (e.g., surface acoustic wave devices) in a sorbent bed of a filtration cartridge, wherein the mass-responsive electronic sensors are coated with a non-conductive absorptive organic polymer; passing a gas containing a volatile chemical of interest through the filtration cartridge and in contact with the two mass-responsive electronic sensors; and measuring a difference in an electronic property between the two mass-responsive electronic sensors. In such a manner, the two mass-responsive electronic sensors act as internal references with respect to each other, thereby eliminating variations in temperature, interferents, pressure, and the like. When the volatile compound is no longer retained by the sorbent bed, a difference electronic properties of the mass-responsive sensors indicates that the filtration cartridge should be replaced.
REFERENCES:
patent: 3999122 (1976-12-01), Winstel et al.
patent: 4312228 (1982-01-01), Wohltjen
patent: 4472356 (1984-09-01), Kolesar, Jr.
patent: 4543112 (1985-09-01), Ackley et al.
patent: 4572178 (1986-02-01), Takase et al.
patent: 4714486 (1987-12-01), Silverthorn
patent: 4886056 (1989-12-01), Simpson
patent: 4971052 (1990-11-01), Edwards
patent: 5012668 (1991-05-01), Haworth
patent: 5022901 (1991-06-01), Meunier
patent: 5235235 (1993-08-01), Martin et al.
patent: 5287035 (1994-02-01), Carroll et al.
patent: 5315987 (1994-05-01), Swann
patent: 5640952 (1997-06-01), Swann et al.
patent: 5861053 (1999-01-01), Noritake et al.
patent: 6340024 (2002-01-01), Brookman et al.
patent: 6497756 (2002-12-01), Curado et al.
patent: 6758212 (2004-07-01), Swann
patent: 7013891 (2006-03-01), Richardson et al.
patent: 2005/0132681 (2005-06-01), Chu
patent: 2007/0018836 (2007-01-01), Richardson
Hill, Jr. Robert J
Jones Christopher P
McNees Wallace & Nurick LLC
The Boeing Company
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