Aerosol dilution device

Abstract

FIELD: aerosol dilution.SUBSTANCE: invention relates to devices for diluting aerosols and can be widely used at nuclear energy facilities, in medical institutions (oncology centres using beam and radiation technologies for diagnostics and treatment), in pharmaceutical and microelectronics enterprises and other industries where high demands are placed on air purification to ensure special production conditions or high demands on radiation and chemical safety. The device for diluting aerosols comprises a housing, a device for feeding an aerosol, an aerosol filter, a pressure sensor and a dilution ratio setter, a dilution module is installed in the housing of the device, equipped with an inlet fitting for feeding an aerosol, which is also connected to a bypass channel used to remove part of the aerosol, equipped with a HEPA filter, while at the inlet and outlet of the dilution module there are jets, the nozzle diameters of which are in the ratio D1:D2, equal to 2:1, in addition, in the housing at the outlet of the HEPA filter there is a module for regulating the pressure of air purified by the HEPA filter, containing a valve connected to a screw equipped with a handle and a channel for removing purified air, connected, in turn, to a tube installed at the outlet of the adjustment module for feeding this air to the dilution module, the latter is provided at the bottom with a chamber for mixing air with an aerosol to obtain an aerosol with a given dilution ratio at the outlet, as a dilution ratio setter the device is equipped with an electronic a module that provides control of the pressure difference between the aerosol flow in the bypass channel and the purified air supplied to the dilution module, wherein the electronic module is connected to the valve of the control module, the pressure sensors of the dilution module and the light indicators on the device body and the device is also provided with a removable battery, wherein: D1 - diameter of the nozzle of the upper jet of the dilution module; D2 - diameter of the nozzle of the lower jet of the dilution module.EFFECT: increasing the accuracy of the degree of aerosol dilution.1 cl, 6 dwg, 3 tbl

Description

[0001] The invention relates to devices for diluting aerosols and can be widely used at nuclear energy facilities (NEFs), in medical institutions, including oncology centers that use beam and radiation technologies for diagnosis and treatment, at pharmaceutical enterprises, microelectronics and other industries where high demands are placed on air purification to ensure special production conditions, or high demands on radiation and chemical safety.

[0002] A "Concentrated aerosol diluent" is known, comprising a housing with a lid equipped with a filter, and a bottom with an outlet pipe, characterized in that, in order to improve the quality of mixing and to increase the accuracy and determination of the parameters of the aerosol, diametrically located openings are made in the wall of the housing, which are equipped with additional filters, and all the inlet openings are equipped with diaphragms located along the flow path after the filters, while the openings in the diaphragm on the lid are located along the circumference, and the openings in the diaphragms in the side walls are located along the chords.

[0003] Aut. St. of the USSR No. 1153963, IPC: B01F 3 / 02, publ. 05 / 07 / 1985

[0004] A known "Aerosol diluent" comprises a housing made in the form of a shell and bases connected by guide rods and equipped with an inlet and outlet pipe, and a filter installed in the inlet pipe, characterized in that, in order to expand the technological capabilities of the device by ensuring the dilution of high concentration aerosols, the shell of the housing is made of an elastic material.

[0005] Aut. St. of the USSR No. 735288, IPC: B01F 3 / 02, published on May 25, 1980.

[0006] The closest technical solution to the device is the "Aerosol diluent for dust meters" containing aerosol and diluent gas pipelines, in the latter an aerosol filter is placed, characterized in that, in order to expand the range of the aerosol dilution factor of the original aerosol, the aerosol pipeline and the diluent gas pipeline are made in the form of mutually intersecting channels that have the same shape and dimensions of the flow section in the zone of their intersection, while the diluent is equipped with a circulation pump and a flow meter installed in the diluent gas pipeline sequentially along the flow before the filter, and a dilution factor setter and a comparison unit, the first input of which is connected to the output of the flow meter, the second input to the dilution factor setter, and the output to the circulation pump.

[0007] Auth. certificate of the USSR No. 1082471, IPC: B01F 3 / 02, published on March 30, 1984.

[0008] The technical result consists in increasing the accuracy of the degree of aerosol dilution by providing the device with a dilution module containing, at the input and output, nozzles with diameters in a ratio D1:D2 equal to 2:1, and a mixing chamber, as well as by providing the device with a bypass channel for diverting part of the aerosol flow, equipped, in turn, with a HEPA filter, as well as by installing in the device a control module containing a channel for diverting air purified from aerosol by a HEPA filter and a valve for regulating the supply of this air into the mixing chamber of the dilution module, in order to obtain an aerosol with a given dilution factor at the output, as well as by providing the device as a dilution factor setter, an electronic module that ensures control of the pressure drop of the aerosol flow in the bypass channel and the purified air supplied to the dilution module.

[0009] The technical result is achieved by the "Aerosol Dilution Device" comprising a housing, an aerosol delivery device, an aerosol filter, a pressure sensor, and a dilution ratio adjuster. A dilution module is installed in the housing of the device, equipped with an inlet fitting for supplying aerosol, which is also connected to a bypass channel equipped with a HEPA filter for diverting a portion of the aerosol. At the inlet and outlet of the dilution module, nozzles are located, the nozzle diameters of which are in a ratio of D1:D2 equal to 2:1. Furthermore, at the outlet of the HEPA filter, a pressure adjustment module for air purified by the HEPA filter is installed in the housing. The module contains a valve connected to a screw equipped with a handle, and a channel for diverting purified air, which in turn is connected to a tube installed at the outlet of the adjustment module for supplying this air to the dilution module.The bottom of the device is equipped with an air-aerosol mixing chamber to produce an aerosol with a preset dilution ratio. Finally, to control the dilution ratio, the device is equipped with an electronic module that monitors the pressure difference between the aerosol flow in the bypass channel and the purified air supplied to the dilution module. The electronic module is in turn connected to the control module valve, the dilution module pressure sensors, and the indicator lights on the device body. The device is also equipped with a removable battery, which:

[0010] D1 - diameter of the nozzle of the upper jet of the dilution module;

[0011] D2 - diameter of the nozzle of the lower jet of the dilution module.

[0012] “Aerosol dilution device” is illustrated by drawings in Fig. 1, 2 and 3

[0013] Fig. 1 - Aerosol dilution device (general drawing-diagram);

[0014] Fig. 2 - Aerosol dilution device (dilution module diagram);

[0015] Fig. 3 - Aerosol dilution device (control module diagram);

[0016] Fig. 4 - Device for diluting aerosols (graph of the table counter channels in the 1st version);

[0017] Fig. 5 - Device for diluting aerosols (graph of the table counter channels in the 2nd version);

[0018] Fig. 6 - Device for diluting aerosols (graph of the table counter channels in the 3rd version).

[0019] According to Fig. 1, 2 and 3, the "Aerosol Dilution Device" comprises a housing 1 in which a dilution module 2 is installed, provided with an inlet fitting 3 for feeding an aerosol, connected to a bypass channel 4 serving to drain a portion of the aerosol, in which a HEPA filter 5 is installed. The dilution module 2 is provided with nozzles at the inlet and outlet: an upper one 6 with a nozzle diameter D1 equal to 0.8 mm and a lower one 7 at the outlet with a diameter D2 equal to 0.4 mm, which are respectively in a ratio to each other equal to 2:1. Nozzles 6 and 7 are provided with sealing rings 8. At the outlet of HEPA filter 5, a module 9 for regulating the pressure of air purified by HEPA filter 5 is installed, containing a valve 10. The latter is provided with sealing rings 11 and 12. Valve 10 is connected by a screw 13 to a handle 14. The regulating module 9 is also provided with a channel 15 connected to a tube 16 for supplying purified air to dilution module 2.At the outlet of the dilution module 2, an air-aerosol mixing chamber 18 is installed for obtaining an aerosol with a given dilution ratio at the outlet. The device is also provided with an electronic module 19, which ensures control of the pressure difference of the aerosol flow in the bypass channel 4 and the purified air supplied to the dilution module 2, wherein the electronic module 19 is connected to the valve 10 of the control module 9. In addition, the device is provided with a removable battery 20, and the mixing chamber 18 is provided with an outlet fitting 21. Light indicators 22 are installed on the body of the device, which are also connected to the electronic module 19. Finally, the dilution module is provided with two pressure sensors 23 at the inlet and 24 at the outlet, which are also connected to the electronic module 19. The design of the device has the technical possibility of installing nozzles with different nozzle diameters in the dilution module.This allows for seamless integration with various particle counters requiring specific input concentrations, ensuring highly reliable measurement results. An additional advantage is the lack of a clean gas or air source, eliminating the risk of foreign aerosols entering the analyzed system. The chemical composition of the analyzed substance is also not altered.

[0020] In this case, the selected diameters of the replaceable nozzles, depending on the required specified dilution coefficients, can be found in the following numerical values ​​equal to:

[0021] 1) D1=0.8mm, D2=1.0mm; 2) D1=0.8 mm, D2=0.4 mm; 3) D1=0.6 mm, D2=0.5 mm

[0022] 1st option is shown in Table 1 and in the graph - Fig. 4;

[0023] 2nd option is shown in Table 2 and on the graph - Fig.5;

[0024] The 3rd variant is shown in Table 3 and in the graph - Fig. 6, where

[0025] D1 - diameters of the upper jets 6 in the dilution module;

[0026] D2 - diameters of the lower jets 7 in the dilution module.

[0027] These examples of selecting the optimal nozzle diameters for diluting the aerosol with the required concentration and a ratio of 1:100, as well as the test results presented in Tables 1, 2, 3 and Graphs 1, 2 and 3, show that the optimal ratio of the nozzle diameters corresponds to the data in Table 2 and Graph 2, that is, they correspond to: D1 = 0.8 mm, D2 = 0.4 mm and a ratio equal to D1: D2 = 2: 1.

[0028] The aerosol dilution device operates as follows: part of the incoming aerosol flow is directed through the inlet fitting 3 along the bypass channel 4, where the HEPA filter 5 is installed. The remaining part of the flow passes through the dilution module 2. Here, the particle concentration is maintained at a constant level. Dilution module 2 contains two nozzles: the upper one 6 at the inlet with a nozzle diameter D1 equal to 0.8 mm and the lower one 7 at the outlet with a diameter D2 equal to 0.4 mm, which are respectively in a ratio of 2:1. Nozzles 6 and 7 are equipped with sealing rings 8. A smaller part of the flow, passing through the capillary channels of the nozzle of nozzles 6 and 7, is the sampled aerosol. The flow rate is 28.3 l / min, however, at a dilution ratio of 1:100, the rate of this flow is 0.283 l / min. The HEPA filter 5 in the bypass channel 4 captures aerosol particles, forming a flow of purified air, which then enters the control module 9.The air purified from aerosol passes through channel 15 and valve 10 of control module 9, and through tube 16 for supplying purified air enters mixing chamber 18 of dilution module 2. In mixing chamber 18, two flows are recombined: aerosol from the nozzle of lower jet 7 and purified air. The dilution coefficient is determined by the ratio of flow rates in bypass channel 4 and capillary channels of nozzles 6 and 7. The pressure difference is provided by bypass line 4, containing HEPA filter 5 and regulating valve 10 of control module 9. Valve 10 is connected, in turn, to electronic module 19, which sets the required dilution coefficient and allows regulating the back pressure of the air flow using valve 10. Such a mechanism guarantees achievement of the required pressure difference, which is measured by sensors 23 and 24, located at the beginning and end of dilution module 2.The differential pressure value is set by the manufacturer during calibration of the device and is recorded in the electronic module 19. Light indicators 22 on the device body 1 alert the user to deviations in the differential pressure from the set value.

[0029] The aerosol dilution device enables highly accurate aerosol dilution by installing nozzles with an optimal nozzle diameter ratio in the dilution module. This, in turn, allows for the device to be easily combined with various particle counters requiring specific input concentrations, ensuring highly reliable measurement results. An additional advantage is the elimination of the need for a clean gas or air source, as the device uses a bypass duct with a HEPA filter to supply purified air, eliminating the risk of foreign aerosols entering the analyzed system.

[0030]

Claims

An aerosol dilution device comprising a housing, an aerosol feeder, an aerosol filter, a pressure sensor and a dilution ratio setter, characterized in that a dilution module is installed in the housing of the device, provided with an inlet fitting for feeding aerosol, which is also connected to a bypass channel for removing a portion of the aerosol, provided with a HEPA filter, wherein at the inlet and outlet of the dilution module there are jets, the nozzle diameters of which are in a ratio D1:D2 equal to 2:1, in addition, in the housing at the outlet of the HEPA filter there is installed a module for regulating the pressure of air purified by the HEPA filter, which contains a valve connected to a screw provided with a handle, and a channel for removing purified air, connected, in turn, to a tube installed at the outlet of the adjustment module for feeding this air into the dilution module, the latter is provided at the bottom with a chamber for mixing air with an aerosol for obtaining an aerosol with a given dilution ratio at the outlet,the device is equipped with an electronic module as a dilution factor adjuster, which ensures control of the pressure difference of the aerosol flow in the bypass channel and the purified air supplied to the dilution module, while the electronic module is connected to the valve of the adjustment module, the pressure sensors of the dilution module and the light indicators on the device body, and the device is also provided with a removable battery, while:, D1 - diameter of the nozzle of the upper jet of the dilution module; D2 - diameter of the nozzle of the lower jet of the dilution module.

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