Internal heater for preconcentrator

• US 6,656,738 B1
• Filed: 11/17/1999
• Issued: 12/02/2003
• Est. Priority Date: 11/17/1999
• Status: Expired due to Fees

• Current Assignee: Femtometrics, Inc. (BAE Systems Plc)
• Original Assignee: BAE Systems Integrated Defense Solutions, Inc (BAE Systems Plc)
• Inventors: Vogel, George W., Claycomb, C. Rodger Jr., Pflugshaupt, Rick E.
• Primary Examiner(s): LUDLOW, JAN M
• Application Number:
  US09/437,422
• Time in Patent Office: 1,476 Days
• Field of Search: 436/161, 436/178, 436/181, 422/69, 422/70, 422/88, 422/89, 73/233.9, 73/234.1, 95/87, 961/01, 961/04
• US Class Current: 436/161
• CPC Class Codes: G01N 1/40 Concentrating samples
• CPC Class Codes: G01N 1/405 by adsorption or absorption
• CPC Class Codes: Y10T 436/255 including use of a solid sorbent, semipermeable membrane, or liquid extraction
• CPC Class Codes: Y10T 436/25875 Gaseous sample or with change of physical state

Abstract

An apparatus for collecting and detecting chemicals contained in a fluid includes a sorbent element, at least one chemical sensor, a first pump for pumping fluid through the sorbent element and a second pump for pumping fluid to the chemical sensor. The sorbent element contains a sorbent material and a heating element. The first pump pumps fluid into the sorbent element thereby collecting the chemicals on the sorbent material. The heating element provides heat to the sorbent element to desorb the chemicals from the sorbent material. The chemicals desorbed from the sorbent material are then pumped out of the sorbent element and to the chemical sensor. The sorbent material may have a cavity therein with the heating element located in that cavity. Alternatively, the heating element may be interposed between the enclosure and the sorbent material.

Claims

1. A method for collecting and detecting chemicals in a fluid comprising:

(a) providing a sorbent material within an enclosure, the enclosure having an interior wall, the sorbent material having an interior cavity circumferentially spaced inwardly from the interior wall;

(b) introducing the fluid into the enclosure, the introducing comprising passing the fluid through the sorbent material surrounding the circumferentially spaced cavity, thereby collecting the chemicals on the sorbent material;

(c) providing a source of heat within the cavity such that the sorbent material surrounds the source of heat;

(d) radiating heat from the source of heat into the surrounding sorbent material, thereby desorbing the chemicals from the sorbent material; and

(e) transferring the chemicals desorbed from the sorbent material out of the enclosure and to at least one chemical sensor.

2. The method of claim 1, where the introducing fluid comprises introducing a gas.

3. The method of claim 2, where the introducing fluid comprises introducing ambient air.