Device for detection of a partial pressure and method for its operation
In order to provide a device for detection of a partial pressure of a measurement gas contained in a surrounding gas, comprising a measurement space with at least one inlet opening to admit surrounding gas into the measurement space and at least one outlet opening to discharge surrounding gas from the measurement space, a quantity that characterizes the partial pressure of the measurement gas in the measurement gas sensor sensitive to the measurement gas to measure a quantity that characterizes the partial pressure of the measurement gas in the measurement space, as well as readout device to read out the measurement gas sensor as well as a method for its operation, which permit metrological detection of the partial pressure of a measurement gas contained in a surrounding gas with improved chronological and spatial resolution, it is proposed that means to determine a response characteristic of device be provided.
1. A device for detecting partial pressure of a measurement gas within a surrounding gas, comprising:
a measurement space with at least one inlet opening to admit surrounding gas to the measurement space and at least one outlet opening to discharge surrounding gas from the measurement space,
a measurement gas sensor, sensitive to the measurement gas, to measure a measurement quantity characterizing the partial pressure of the measurement gas in the measurement space, and
a readout device to read out the measurement gas sensor for a time series of recorded measurement data, wherein the readout device is configured to determine a delayed response behavior of the device;
a reference gas source to furnish a reference gas, the reference gas source is configured to generate the reference gas from the surrounding gas;
wherein the measurement space is provided a flow of the reference gas to which the measurement gas sensor is not sensitive.
2. The device of claim 1 , wherein the readout device includes a correction gas sensor, sensitive to a correction gas, to measure a measurement quantity characterizing a partial pressure of the correction gas in the measurement space and a readout device to read out the correction gas sensor, in which the correction gas is contained in the surrounding gas or different from the measurement gas.
3. The device of claim 2 , wherein the correction gas sensor is not chemically sensitive to the reference gas.
4. The device of claim 1 , wherein the reference gas source removes the measurement gas from the surrounding gas or that the reference gas source chemically converts the measurement gas so that the measurement gas sensor or the correction gas sensor is not sensitive to the gaseous conversion products that form during the conversion.
5. The device of claim 4 , further comprising a control and evaluation unit for control of the flow through the measurement space in order to initiate and disconnect the flow of reference gas through the measurement space.
6. The device of claim 5 , wherein the control and evaluation unit is designed for computer determination of the delayed response behavior from the temporal time series of the recorded measurement data via the readout device of the measurement gas sensor or via the readout device of the correction gas sensor.
7. The device of claim 5 , wherein the control and evaluation unit is designed for computer compensation of the delayed response behavior of the measured data recorded via the readout device of the measurement gas sensor.
8. The device of claim 1 , further comprising a membrane, upstream of the at least one inlet opening or downstream of the at least one outlet opening, the membrane permeable to the surrounding gas is arranged so that the surrounding gas enters the measurement space through membrane or the surrounding gas leaves the device through membrane.
9. The device of claim 1 , further comprising a bypass line that connects the at least one inlet opening to the at least one outlet opening.
10. The device of claim 1 , wherein the measurement gas sensor or the correction gas sensor includes an optical gas sensor, a non-dispersive infrared sensor or spectrometer based on a tunable laser diode, or a pump to circulate the surrounding gas through the measurement space.