SU1479850A1 - Device for determining content of dissolved gases and liquid - Google Patents

Abstract

The invention relates to a fermentation technique, in particular, to devices for determining the content of dissolved gases in a liquid directly in process equipment. The goal is to increase accuracy. A sensor with a heat exchanger is placed in the reference liquid, which, through the heat exchanger, the inlet pipe 34 and the tube 15 enters the cavity 16 of the reference container 3 and then goes outside. Inert gas from cylinder 10 enters the carrier gas line 22,23. Passing through the helix of line 22, the inert gas is saturated by the gases diffusing through the silicone tube 2, dissolved in the test liquid. Formed with a gas mixture through the channel 24, the flow hole 26 and the channel 4 of the output of the carrier gas enters the chromatograph. 2 Il.

Description

(21) 4156807 / 28-26

(22) 12/08/86

(46) 05/15/89. Bul Number 18

(71) All-Union Scientific Research Institute of Biological Instrument Making

(72) V.N. Khoz ychikov and D.P. Lebedev

(53) 6.847.356 (088.8)

(56) USSR Author's Certificate No. 987463, cl. G 01 N 7/10, 1983.

(54) DEVICE FOR DETERMINING THE CONTENT OF DILUTED GASES IN A LIQUID

(57) The invention relates to a fermentation technique, in particular, devices for determining the content of dissolved gases in a liquid.

directly in technological devices. The goal is to increase accuracy. A sensor with a heat exchanger is placed in the reference liquid, which, through the heat exchanger, the inlet pipe 34 and the tube 15 enters the cavity 16 of the reference container 3 and then goes outside. Inert gas from cylinder 10 enters the carrier gas lines 22, 23. Passing through the helix of line 22, the inert gas is saturated by the gases diffusing through the silicone tube 2, dissolved in the test liquid. Formed with a gas mixture through the channel 24, the flow hole 26 and the channel 4 of the output of the carrier gas enters the chromatograph. 2 Il.

$

eight

Jt. 72

four

WITH

oo

SP

tpuef

one

14,798

The invention relates to a fermentation technique, in particular, to devices for determining the content of dissolved gases in a liquid directly in process equipment, for example, in fermenters.

The aim of the invention is to improve the accuracy.

Fig. 1 schematically shows a device for determining the content of dissolved gases in a liquid; figure 2 - the change in the error rf of the known proposed device. About

A device for determining the content of dissolved gases in a liquid contains a sensor 1 with measuring 2 and reference 3 capacitances with gas-permeable walls connected through channels 4 and 5 of the output of the carrier gas to the gas analyzer 6, for example, a chromatograph, and the nozzle 7 of the carrier gas through a flow regulator 8, a reducer 9 is attached to a cylinder 10 with an inert carrier gas, for example helium.

Measuring 2 and reference 3 capacitances of sensor 1 are made in the form of coaxially arranged tubes, for example, of silicone rubber, mounted on the upper 11 and 12 and lower 13 and 14 end cones. In the reference container 3, along its axis with a gap in the lower end, a tube 15 is installed, the upper end of which is fixed in the upper 12 end cone.

The tube 15, the internal cavity 16 of the reference container 3, the channel 17 in the housing of the upper 12 face cone and the nozzle 18 of the output of the reference fluid form a fluid pumping line. A cylindrical partition wall 19 is installed between measuring 2 and reference 3 capacitances with ribs 20 and 21 located on both its sides along a helical line and adjacent to the walls of containers 2 and 3, which form the carrier gas lines 22 and 23 which are connected by channels 24 and 25 located in the housing of the lower end of the cone 13, through isolated from each other flow holes 26 and 27 in the common bottom 28 of the lower end cones 13, 14 and nozzles 29 and 30 with channels 4 and 5 of the output of the carrier gas. The lower ends of the pipes 29 and 30 are fixed in the lower end cone 14. The bottom 28

ten

five

0

five

0

five

0

five

0

five

50 2

using the spring 31 and the wingopon cover 32 is hermetically pressed to the base of the lower end cones 13 and 14.

Nozzles 29 and 30 of the output of the carrier gas are placed in the internal cavity

16 and are adjacent to the walls of the pipe 15 for pumping a standard liquid fluid and are in thermal contact with it.

The temperature control system is made in the form of a heat exchanger 33 connected to the standard liquid inlet pipe 34, and a heater 35 which is additionally introduced into the reference tank 3 and has the Same resistance and winding pitch with the heater 36 located in the measuring tank 2 and connected to the heater 35 in series. Both the heaters 35 and 36 are in thermal contact with the containers 2 and 3, respectively, and connected to the regulated current source 37. Thermal resistance 38 and 39, respectively, is wound on each heater 35 and 36. Thermal resistors 38 and 39 are connected to temperature detection unit 40.

The device works as follows.

The sensor 1 together with the heat exchanger 33 is placed in the test liquid. The reference fluid (water) through the heat exchanger 33 through the inlet pipe 34 and the tube 15 enters the cavity 16 of the reference tank 3 and through the channel

17 and nozzle 18 is led outside. Inert gas from cylinder 10 through

the reducer 9 and the flow regulator 8 are supplied through the inlet 7 of the carrier gas to the lines 22 and 23. Passing through the helix of line 22, the inert gas is saturated with the gases diffusing through the silicone tube (container) 2 dissolved in the test liquid. The gas mixture formed through the channel 24, the flow hole 26, the pipe 29 and the carrier gas outlet channel 4 enters the measuring arm of the chromatograph 7. The inert gas passing through the line 23 is saturated with 3 gases diffusing through the silicone tube (tank) in the reference gas. the fluid flowing in the cavity 16 of the reference tube 3, flows through the channel 25, the flow hole 27, the pipe 30 and the channel 5

The output of the glutiner is the griller arm of the chromatograph 7. In the bridge circuit of the chromatograph 7, the signals appearing in its shoulders are compared, and their difference is proportional to the absolute value of the concentration of dissolved gases in the liquid. The permeability of silicone tubes is significantly dependent on temperature. Figure 2 shows the change in the additional Ј error that occurs when the partial pressure changes as a result of a change in the temperature of the reference liquid (water) by 10 ° C (1 - mixture from 18.7% 0, stirrer speed 340 rpm, known device 2 the same, the proposed device). Such conditions arise during the operation of the temperature control system (the water heater entering into it) located at some distance from the technological apparatus (fermenter).

Claims (1)

Invention Formula A device for determining the content of dissolved gases in a liquid, containing a sensor with tanks with gas-permeable walls: measuring, equipped with a heater, and a reference with a line for pumping the standard liquid with inlet and outlet nozzles, lines of passage of carrier gas through the tanks an input spout and autonomous outlet connections connected to the gas analyzer, and a temperature control system, so that, with a circuit for increasing the accuracy of measurement, the measuring and reference capacitance of the sensor are made in the form of two coaxialites tubes, while in the reference tank along its axis with a gap is installed a tube, which forms with the internal cavity of the reference tank a pumping line for the liquid and a passageway 5 of the carrier gas is formed by a cylindrical partition mounted between the measuring and reference containers with ribs located on both sides of the partition along a helical line. 0 and adjacent to the walls of the containers, and the nozzles of the output of the carrier gas are placed in the internal cavity of the reference container and adjacent to the walls of the tube pumping pipeline reference 5 of the liquid and being in thermal contact with it, the temperature control system is made in the form of a heat exchanger and an additional heater introduced into the reference tank, 0 having the same resistance and winding pitch with a heater located in the measuring tank and connected to it in series, and the heaters are connected to an adjustable current source. (f 9 8 7 6 5 t3 2 J0 J5 Editor L. Veselovska Compiled by S. Kiselev Tehred I. Veres Corrector. Kravtsov Order 2536/42 Circulation 790 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 .... .. "., ...." ..... "..- -,". ".-. ---.-.-.-.-.-. And ... .-- ---- - -. - - - -. Production and publishing plant Patent, Uzhgorod, st. Gagarin, 101 40 t ° c 2 Subscription