Chemistry: analytical and immunological testing – Metal or metal containing
Reexamination Certificate
1998-10-21
2001-03-13
Soderquist, Arlen (Department: 1743)
Chemistry: analytical and immunological testing
Metal or metal containing
C422S088000, C422S062000, C436S025000, C436S026000, C436S081000, C436S083000, C436S177000, C436S178000, C436S182000
Reexamination Certificate
active
06200816
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a method and device for measuring metals in a fluid stream, and more specifically, this invention relates to a method and device for simultaneously measuring metals in a gas stream while also providing archival samples.
2. Background of the Invention
The problems associated with the presence of metal particulates in air due to combustion and other activities continue to increase. As a result, the U.S. Environmental Protection Agency requires analysis of a number of metals in gas streams from combustors, incinerators, and other such entities.
Also, many industrial processes depend on the analysis of process streams before and/or after certain operations.
Present sampling techniques include manual stack sampling, which involves wet chemical analysis and the concomitant long delay in getting the results. Furthermore, such analysis usually results in destruction of the sample so that sample archiving is not possible. Nondestructive analysis is sometimes valuable in instances where confirmation of test results is desired long after initial sampling and reporting is made.
Generally, particulates in gas streams are analyzed by diverting a known portion of the stream to pass through a filter media onto which the particulate sample is collected. The sample is then moved to a means for analyzing the sample. Usually, the collection process needs to be halted so as to facilitate removal of the filter media.
Typically, gaseous metals entrained in the stream are collected by passing a known portion of the stream into some means for collecting such samples, such as a cold condenser or a liquid impinger where the metal sample condenses out or precipitates out. The metal sample must then be collected from the condenser or recovered from the liquid before an analysis of the sample can be made.
Devices exist for detecting the presence of certain analytes in a sample. For example, U.S. Pat. No. 5,541,057 to Bogart et al., utilizes an optically active surface to facilitate assays of biological analytes. U.S. Pat. No. 5,460,973 utilizes a combination of distillation and head space analysis to measure volatile impurities.
Other devices exist for collecting metals in the atmosphere. One such device, U.S. Pat. No. 3,940,614 to Rhodes, utilizes a high volume air sampler combined with noble-metal-coated fibrous packing. The device facilitates the collection of mercury vapor. However, no provision is made for particulate collection or analysis.
A need exists in the art for an inexpensive method and device to simultaneously measure particulate and vapor phases of metals contained in a fluid. The method and device should be adaptable to on-line operations and to installation on mobile units. The method and device should also provide for archive sampling.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a method and a device for the measurement of the solid-phase and vapor-phase metals that overcomes many of the disadvantages of the prior art.
Another object of the present invention is to provide a method and device to simultaneously measure metal particulates and metal vapor in a flue stream. A feature of the invention is the use of a continuous sampling media. An advantage of the invention is the facilitation of near real-time sampling of the metal content in the flue stream.
Yet another object of the present invention is to provide an economical method and device for analyzing metals in a gas stream. A feature of the invention is contacting the gas stream with a continuous surface comprising an adsorbent and subsequently analyzing the surface with a standard x-ray fluorescence analyzer. Another feature of the invention is that the surface can be temperature adjusted to capture and remove volatile matter such as lower boiling point chemicals and metals. An advantage of the invention is the use of standard materials and methods to provide a rapid analysis of metal content in the gas stream.
Still, another object of the present invention is to provide a method and device for capturing and retaining target matter for analysis. A feature of the invention is utilizing a plurality of adsorbents to capture the matter. An advantage of the invention is the capture and retention of different types of matter for instant analysis or archival purposes.
Briefly, the invention provides for a method for analyzing metal in a fluid comprising supplying a continuous filter media substrate; maintaining a first portion of said filter media substrate at a temperature coinciding with the phase in which the metal is to be analyzed; contacting the fluid to the first portion of said substrate to retain the metal on the first portion of said substrate; preventing further contact of the fluid to the first portion of said substrate; and contacting the fluid to a second portion of said substrate to retain metal on the second portion of the said substrate while simultaneously analyzing the first portion for metal, whereby the second portion of said substrate is integral to the first portion of said substrate.
The invention also provides for a device for analyzing metal in a fluid comprising a continuous filter media substrate; means for maintaining a first portion of said filter media substrate at a temperature coinciding with the phase in which the metal is to be analyzed; a means for contacting the fluid to the first portion of said substrate; a means for preventing further contact of the fluid to the first portion of said substrate; a means for contacting the fluid to a second portion of said substrate to retain metal on the second portion of the said substrate; and means for analyzing the first portion for metal, whereby the second portion of said substrate is integral to the first portion of said substrate.
These and other features and advantages of the invention will be apparent from the detailed description of the invention and from the claims.
REFERENCES:
patent: 3061723 (1962-10-01), Kapff
patent: 3098719 (1963-07-01), Skeggs
patent: 3940614 (1976-02-01), Rhodes et al.
patent: 4056969 (1977-11-01), Barringer
patent: 4568520 (1986-02-01), Ackermann et al.
patent: 4742009 (1988-05-01), Beverly et al.
patent: 5637506 (1997-06-01), Goken et al.
W. Dannecker et al. Staub—Reinhalt. Luft 1983, 43, 253-258, Jun. 1983.
K. E. Lorber Waste Manage. Res. 1986, 4, 3-13, Jan. 1986.
K. Yasuda et al. Taiki Osen Gakkaishi 1986, 21, 191-196, Mar. 1986.
W. J. Smith et al. Am. Ind. Hyg. Assoc. J. 1986, 47, 779-784, Dec. 1986.
J. A. Cooper Fuel Process. Technol. 1994, 39, 251-258.
M. B> Bernick et al. J. Hazard. Mater. 1995, 43,91-99.
E. M. Prestbo et al. Water, Air, Soil Pollut. 1995, 80, 145-158.
B. S. Turk et al. High Temp. Gas Clean., 3rd, E. Schmidt ed., Institut fuer Mechanische Verfahrenstchnik und Mechanik der Unviversitaet Karlsruhe: Karlsruhe, Germany, 1996, pp. 302-315.
O. Haupt et al. X-Ray Spectrom. 1997, 26, 79-84, Feb. 1997.
G. M. Thomson et al. Am. Ind. Hyg. Assoc. J. 1997, 58, 98-104, Feb. 1997.
Farber Paul S.
Huang Hann-Shen
Dvorscak Mark P.
Gottlieb Paul A.
LaMarre Mark F.
Soderquist Arlen
The United States of America as represented by the Department of
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