SU395025A1 - Gas analyzer - Google Patents

Description

one

This invention relates to a gas analytical instrumentation based on thermochemical methods for quantifying the content of combustible components in the analyzed gas mixture, for example, in exhaled air.

Currently, special indicator tubes containing a solution of a reagent (e.g. potassium dichromate, sodium permanganate, etc.) that change color when interacting with alcohol vapor are used to determine the alcohol vapor in the exhaled air. According to the degree of intensity of the color of the solution, the quantitative content of alcohol vapors is judged; in exhaled air.

The tubes are highly sensitive not only to ethyl alcohol, but 1and to its closest homologues (for example, acetone, ether, etc.), which does not allow

objectively assess the content of alcohol vapors in exhaled air. Based on the indicator, different gas analyzers have been developed, among which semi-automatic

Tic colorimeter with photoelectric transducer following equilibration. Dose collection in it wasp; there is a piston gauge and a cylinder, from which the gas is analyzed after lifting to the upper position

BMxomiT mixture into the atmosphere. After a manual overlapping of the inlet channel, the piston with its own weight forces the gas out of the cylinder into the vial with the liquid reagent. The disadvantage of this device is its low accuracy due to sensitivity to various impurities.

Gas analysis devices are known in which, the effect of thermal catalytic combustion on the sensitive element of the measuring bridge of alcohol vapors previously accumulated on the granular adsorbent is used. The desorption of the alcohol vapor is carried out by thermal path (heating the helix inside which the adsorbent is located).

The devices are semi-automatic and equipped with a manual pump to purge the gas lines from the residual products of the analysis, which complicates the operation of E7 devices. The irrational construction of the heating coils, inside of which the adsorbent is located, not only shields the latter from direct passage of the gas mixture, but also leads to significant losses of the useful dose of the gas mixture being analyzed. All this. reduces the effect of sorption, the sensitivity of the breaker and the accuracy of the gas analysis. In order to increase the accuracy of the analysis in the proposed device, the non-operating device of the piston dose setting unit is connected by a gas channel to the inlet of the reaction chamber. The heating coil is made in the form of a truncated cone with a smaller diameter at the base, built into a special cassette, the internal channel of which coincides in shape with the shape of the heating spiral and passes into a cylindrical guide knee for communication with gas combs II. To eliminate burning, the cassette is made of heat-resistant SALT-INSULATED materials, such as ceramics. Such an implementation of the heating coil and the cassette allows for more intensive adsorbent extraction by the gas stream under study without significant losses. The gas flow is created due to the elimination of a negative piston from the capillary unit of the dose of the gas mixture formed in it during the process of blowing exhaled air. To clean the gas communications from the residual products of the combustion channels, the channels are blown with clean air, the ingms flow in the adressor prior to the entry of the test; A new dose of the test gas mixture is being prepared, and at the same time the gas lines are being cleaned of residual impurities from the previous analysis. FIG. 1 shows a block diagram of a device including the described device; in fig. 2 - the described device. The unit diagram of the device consists of a gas piping (lytic device 1, relay-logic (OWN of block 2, measuring device 3 of program mechanism 4, console jTipaB of laziness 5, power supply unit 6. The device consists of water separator t | with internal partitions 8, excluding penetration moisture or other mechanical remittances into the output gas; channel 9 when blowing the gas mixture through the inlet pin 1O; two-way elec- tro magnetic valve 11 with three pass-holes | a-aiff-S ib-6; a calibrated setting; 12 doses with free sweep There are porschs inside it 13. There are 14 inlets in the cylinder cylinder and inlet 14 and outlet 15 inlets. The inlet inlet contains a check valve: 16. In the upper part of the sampler there is a mechanical valve with a lever 17, a return spring and a spool 10; dissolving channel 20 with a check valve 2р- "gas outlet channel 22c with a check valve 3, a button 24 for launching the program mechanism and a channel 25 for the expired gas mixture into the atmosphere. The reaction chamber 26 contains a separate cartridge 27 and a detector 28 placed on one side carc Ace working and comparative sensory and element-1 Tami 29, In the separation cassette there is an AOR heating coil, made in the form of a truncated cone, the adsorbent 31 in the form of granulated alumina and placed inside the heater with Ira, a cap 32 with a sleeve of 3 3 that holds the adsorbent inside the heater-1 spiral. In the separation cassette there is an inlet 34 for the gas mixture under study and an inlet 35 for clean air. Both; the input, connecting, goes to the sawing-I-shaped guide elbow 36, the diameter of which corresponds to the smaller diameter of the heating cone. For thermostabilization, the described device is equipped with heating spins 37, which are controlled by a thermal contact device. The device operates as follows. Upon a command from the control panel, the solenoid valve 11 is opened, which opens aa and bb openings. Hole i5 - b is blocked. The incoming gas mixture raises the dose setting piston to the extreme Bepxiiero position and sets in motion the mechanical valve, opening the channel 25 to open the excess gas of the investigated gas mixture to the atmosphere. For a more intensive enrichment of the entire receiving cavity of the dose setting device by the gas mixture under study, the process of blowing. neither after, does ana lead for a certain time interval specified by pro. : by the gram mechanism. When lifting up the clean air from the above-piston non-hour barrel chamber and through the gas channel 22 and oTBepCTi Fe 6-6 electrons of the diesel valve cleans the reaction chamber from the residual gas products. j The program mechanism is launched when j1 is processed by the 24 stove at the moment of its interaction with the piston,;

After a predetermined duration, the holes ci-cl and B-6 overlap; and through the opening of the ET-S under the piston's accumulated weight, the dose of the tested single mixture is displaced from the setter into the reaction chamber.

Piston lowering time Her SU Ug: by changing the cross-section of the bore hole in the iggutser 15. After some time, fasting; Gzvt command to activate the heating spiral ZO and warm up; sensitive ele .1. N-1OV 29 measuring device 3

smells after it is established, 5) the weight of the measuring bridge, the shoulders, ... :: pogo are sensitive elements. When the heating temperature i is increased. ... a helix creates a convective,. hashes air through the gas channel in t -iobepy. When this starts, desorption and .u. "Peiroc. alcohol vapor heat flow, .1, l on hot working and comparative sensitive elements. Combustion of alcoholic alcohol on the work item causes imbalance of the engine by a quantity proportional to

the amount of alcohol vapor present in the gas mixture being studied

To eliminate possible condensation of moisture in the gas mains, gas temperature is maintained in the gas 5 block of the probe, higher than the temperature of the gas cMecii under study.

The device makes it possible to significantly reduce the time for analysis and automatize it, which makes it more effective to control the content of the component to be detected in the gas mixture under study, in particular, to control the alcohol content in the exhaled air.

Formula and a boutheni

A gas analyzer comprising a piston dose setting unit and a reaction chamber; different

the fact that, in order to improve the accuracy of the analysis, the non-working cavity of the setter is connected by a gas channel to the entrance of the reaction chamber.

FIG. /

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