Analysis system for an atmosphere tracer dispersion system

• US 3,991,626 A
• Filed: 04/07/1975
• Issued: 11/16/1976
• Est. Priority Date: 04/07/1975
• Status: Expired due to Term

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Shair, Frederick H.
• Primary Examiner(s): Gill, James J.
• Application Number:
  US05/565,780
• Time in Patent Office: 589 Days
• Field of Search: 73/421.5 R, 73/422 GC, 73/425.6, 73/23.1, 128/234-237
• US Class Current: 73/23.4
• CPC Class Codes: G01N 27/66 and measuring current or voltage
• CPC Class Codes: G01N 30/06 Preparation
• CPC Class Codes: G01N 33/0011 Sample conditioning preparing specimens for investigation G01N1/28

Abstract

A system for atmospheric monitoring is disclosed. Atmospheric dispersion of a plume is monitored by continuously releasing a tracer gas such as sulfur hexafluoride into the plume, collecting air samples downwind and analyzing the samples. The system includes plastic piston pump samplers having a locking outlet receiving removable nozzles or a lock-seal closure. The samples are analyzed by means of a tracer specific gas-chromatograph-electron capture (GC-EC) detector having a lock-seal inlet adapted to engage the sampler outlet. In a preferred system, the atmospheric samples are collected by automatic, sequentially operated samplers and analyzed by means of a plurality of GC-EC detectors operating in parallel such that the trailing oxygen band is eluted through the first detector as the last detector is being loaded. Thus, the system is in continuous operation and minimizes operator time, and 80 samples can be analyzed in one hour. A multiple input, digital integrator having means for integrating peaks formed during baseline drift provides continuous, reliable read-out data from the signals from the multiple GC-EC detectors.

Claims

1. A gas analysis system comprising in combination:

a piston-pump sampler comprising a hypodermic syringe including a synthetic, plastic housing defining a sample chamber, a piston housed with the chamber, a plunger secured to the piston and extending out of one end of the chamber, an outlet at the other end of the chamber and a threaded annular member secured to said body surrounding said outlet;

a gas analysis unit having an inlet adapted to sealingly engage the threaded annular member of the sampler outlet during injection of sample into the unit;

a needle assembly configured to sealingly and releasably engage said threaded annular member; and

a sealing member adapted to releasably and sealingly engage said threaded annular member.

2. A system according to claim 1 in which the gas analysis unit is a gas chromatograph with an electron-capture detector.

3. A system according to claim 1 in which the annular member is cylindrical and contains internal threads and concentrically surrounds a short deformable outlet tube connected to the outlet and said inlet member contains an outer shoulder member for engaging said threads and an inner tapered recess for sealingly engaging said tube.