SU88550A1 - Method of gas analysis - Google Patents

Description

The subject of the invention is a method of analyzing gases according to the degree of absorption by the component under study of light rays of a certain wavelength, directed to the test mixture of gases through a filter, using a photocell to determine the degree of absorption.

The proposed method differs from the known mixture of alternating irradiation of the gas mixture under study (by means of moving optical filters) by light rays with a sectoral composition absorbed and not absorbed by the test component.

FIG. 1, 2 and 3 shows the device in three versions for the axle; demonstration of the method.

The test gas (for example, CO,) passes through a tube that is transparent to infrared and visible rays /. The rotor is mounted in front of the tube; the ice (or rocking) obturator 2 with built-in light filters 3 and 4. Radiation energy, whose spectral composition is determined by, 1, passes through the tube / photocell 5 from the radiation source 6; The effective wavelengths are such that the flux of radiant energy transmitted by filter 5 is absorbed by CO. I.e., the effective wavelength lies near infrared frequencies. The flow of radiant energy transmitted by the filter 4 passes through the flow of the test gas unhindered. Then, obviously, measuring with

of any known device 7, the ratio of these two streams, it is possible to measure the concentration of COj and at the same time eliminate the instability of the photocell 5 and the photo booster 8).

In the variant of the device (fig. 2), a diagram is given, where the content of CO.J is also determined by the ratio of two fluxes of radiant energy, but already of the same spectral composition. According to this scheme, the flow of radiant energy from the radiation source 6 is supplied with the help of an optical device consisting of, for example, a condenser .9, mirrors 10 and 11 n of the Lummer cube 72, into the photocell 5, pepe 5, then through the vessel 13 with the test gas through the vessel

14, filled with CO. known concentration.

The unknown concentration at the output of the photocurrent amplifier 8 is also determined using instrument 7 with respect to the photocurrents.

The advantage of the latter scheme is the possibility of eliminating instability of the operation of the radiator 6; The disadvantage is the lack of complexity of the optical system.

Scheme III of the variant of the device differs from Scheme II of the variant by the absence of a vessel with a gas of known concentration.

In this scheme, the effect on the absorption of the remaining gases in the composition of the mixture under study can be taken into account, for example, by absorbing glass 15 (shown by dotted lines).

Subject invention

The method of analyzing gases according to the degree of absorption by the component under study of light beams of a specific wavelength, directed to the test mixture of gases through a filter, is used to determine the degree of absorption of a photocell, characterized in that, in order to improve the measurement accuracy, the light under test having a spectral composition, absorbed and not absorbed by the studied component.

FIG. one

h