Process and arrangement for determining at least one component of a test gas

• US 5,093,269 A
• Filed: 11/03/1987
• Issued: 03/03/1992
• Est. Priority Date: 12/20/1986
• Status: Expired due to Fees

• Current Assignee: Dragerwerkk AG Moislinger Allee
• Original Assignee: Dragerwerk AG
• Inventors: Matthiessen, Hans, Leichnitz, Kurt
• Primary Examiner(s): Lacey, David L.
• Assistant Examiner(s): Snay, Jeffrey R.
• Application Number:
  US07/116,640
• Time in Patent Office: 1,582 Days
• Field of Search: 422/88, 73/23, 73/863.11, 73/863.12, 73/23.1, 340/632, 324/71.1 R, 55/205, 55/179, 436/178
• US Class Current: 436/178
• CPC Class Codes: G01N 33/0062 concerning the measuring method, e.g. intermittent, or the display, e.g. digital
• CPC Class Codes: Y10T 436/255 including use of a solid sorbent, semipermeable membrane, or liquid extraction

Abstract

A process for determination of one component of very low concentration in a test gas, which is guided in a supply line for concentration of the component across a sample collector, whose amassed quantity of samples is relinquished to a detection sensor. The arrangement makes available a measurement signal even during the collection of the sample. It also makes even the individual components of a multicomponent test gas detectable and a component-specific cross sensitivity of the detection sensor controllable. For this, the following process steps are provided: the test gas is first guided across the detection sensor 3 and then across the multistaged sample collector 7 having arrangements for separation of the several components; then after interruption of the supply of test gas, each individual stage 4, 5 and 6 separately relinquishes its separated component to the detection sensor 3.

Claims

1. A process for determining at least on component of lower concentration of a test gas sample using a gas concentration sensor and a sample collector with means for concentrating at least the one component of the test gas, the process comprising the steps of passing the test gas sample across the sensor while obtaining a combined concentration reading of said test gas sample from the sensor;

passing the test gas from the sensor to the sample collector to concentrate each of said at least one component therein;

interrupting the supply of said test gas to the sensor and separately supplying only each collected component from the sample collector to the sensor and obtaining a component-specific concentration reading therefrom.

2. A process according to claim 1 wherein said sample collector comprises a plurality of stages arranged in series, each stage concentrating a different component of the test gas, further comprising the steps of supplying each collected component sequentially to the sensor and obtaining sequential component-specific concentration readings therefrom corresponding to the concentration of each of said at least one component in said test gas supplied to the sensor.

3. A process according to claim 2 in which each collector stage includes an adsorption layer for one of said at least one component, further comprising the steps of cooling the test sample during its passage across the sensor and to the collector stages and subsequently heating the respective collector stages sequentially for supply of the respective components concentrated therein to the sensor.

4. A device for determining a plurality of gas components from a test sample, comprising means defining a test gas passage, a sensor in said test gas passage for detecting the concentrations of a plurality of different gases in said test gas passage, a plurality of gas collection stages arranged in said test gas passage downstream of the sensor, each stage having means for separating a separate gas component and a separate exit line extending to said test gas passage, a direction control valve located at a connection of said exit lines to said test gas passage, a gas supply inlet line connected to said direction control valve and a discharge line connected to said direction control valve, control means connected to said direction control valve for regulating the connection of said stage exit lines to said test gas passage and said inlet and discharge connections and for directing each separated gas component individually to said sensor separately from each other and from the gas supply.