CN213041596U

CN213041596U - Portable gas collecting device for LIBS measurement

Info

Publication number: CN213041596U
Application number: CN202022137659.5U
Authority: CN
Inventors: 张可为; 潘苑茹; 张宇梁
Original assignee: China Jiliang University
Current assignee: China Jiliang University
Priority date: 2020-09-25
Filing date: 2020-09-25
Publication date: 2021-04-23
Anticipated expiration: 2030-09-25

Abstract

The utility model provides a can be used to LIBS measuring portable gas collection device for heavy metal element's content in the measured gas. The whole device comprises three parts of gas collection, gas treatment and gas detection, the device is controlled by a console, the gas collection part comprises a gas suction channel, a gas suction pump, a gas chamber, a gas exhaust channel and a gas exhaust pump, the gas treatment part comprises a temperature sensor, a pressure sensor and a piston, the piston is positioned at the bottom of the gas chamber and is connected with a piston rod, the piston rod is controlled by a connecting rod and a turntable to move, the gas detection part comprises a LIBS spectrum measurement system, a laser generator and a focusing lens are positioned right above a quartz window of the gas chamber, and a spectrum acquisition system is positioned outside the side wall of the gas. The top of the device is provided with a portable handle. The device can collect fast and LIBS detects gas, has the characteristics of high gas detection efficiency and high accuracy.

Description

Portable gas collecting device for LIBS measurement

Technical Field

The utility model relates to a spectral measurement analysis technical field, concretely relates to gaseous collection device of measurement that can be used to LIBS.

Background

At present, heavy metal pollution causes serious harm to ecological environment and people's life, untreated industrial waste gas is a main pollution source caused by heavy metal elements, heavy metals in the atmosphere mainly come from gas and dust generated in energy, transportation, metallurgy and building material production, the aspects are closely related to human life, and when the heavy metal pollution is more and more serious, people are concerned about the content of the heavy metal elements in the gas, which is a topic that people cannot neglect.

Laser-induced breakdown spectroscopy (LIBS for short) is a novel substance analysis and detection technology, in which ultrashort pulse Laser is focused on the surface of a sample to form plasma, and then plasma emission spectrum is analyzed to determine the substance composition and content of the sample, the energy density is high after the ultrashort pulse Laser is focused, and samples in any form can be excited to form plasma, so that the technology can theoretically analyze samples in any form.

When LIBS measures heavy metal components and their contents in a gas, it is first necessary to collect a sample of the gas to be measured on site and then take it back to the place where LIBS apparatus is installed for measurement. During measurement, gas is firstly input into a sample chamber of the measuring device, then a gas sample is processed in the sample chamber, and finally the measurement can be started. The device of this scheme to the adoption when collecting gas does not do too much requirement, so can appear some errors when gas is collected and lead to the measuring result not so accurate to can not directly measure the gas sample after the gas sample is collected, need take the sample back and just can measure, it is slower to obtain the result, can spend a lot of time, and the efficiency ratio is lower, and is convenient direct inadequately.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving foretell problem, and the portable gas collection device who can be used to LIBS measurement that proposes, this device not only can be used for collecting the gas that awaits measuring, can also handle the sample with the device after collecting, then directly measures and directly obtains the result with the LIBS technique to heavy metal composition in the gas and content thereof.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a portable gas collecting device for LIBS measurement is characterized in that the gas collecting and detecting device integrates the collection, processing and detection of the gas to be measured, can directly detect after the collection of the gas sample is finished, the whole device is of a cylindrical structure, wherein the gas collecting part consists of a gas chamber (13) positioned in the center of the inside of the whole device, a suction pump (7), a suction channel (16), an exhaust pump (8) and an exhaust channel (17), the suction pump (7) and the exhaust pump (8) can be controlled by a console (4) of the whole device, when the air suction or air exhaust work is finished, the air suction channel (16) and the air exhaust channel (17) can be closed under the control of the console (4) to form a closed environment in the air chamber (13), and a display screen (3) arranged on the console (4) can display the volume of the gas in the gas chamber.

The utility model discloses in to the gas that awaits measuring handle the part and include: piston (9), piston rod (10), connecting rod (11), carousel (12), temperature sensor (6), baroceptor (15) and control line two (21), and temperature sensor (6) and baroceptor (15) can pass to control cabinet (4) with the inside real-time temperature of air chamber (13) and real-time pressure, then show through display screen (3) on control cabinet (4), are convenient for observe the inside condition of air chamber (13). The control console (4) can control the rotation of the rotary table (12) through a second control line (21), and the rotary table (12) controls the movement of the piston (9) and the air pressure in the air chamber (13) through rotating the control connecting rod (11) and the piston rod (10).

The utility model discloses the part that detects is carried out to the gas that awaits measuring in includes: the LIBS spectrum collection system comprises a laser (2), a lens (14), a LIBS spectrum collection system (5), a control line I (19), a transmission line (20), a quartz window I (22) and a quartz window II (23), wherein the laser can emit laser under the control of the control line I (19) on a control console (4), the laser is converged by the lens (14) and then is emitted to the surface of a sample through the quartz window I (22) to generate plasma, the quartz window II (23) plays a protection role in the LIBS spectrum collection system (5) in a gas chamber, the LIBS spectrum collection system (5) receives the spectrum emitted by the plasma in the gas chamber (13), then the signal is transmitted to the control console (4) through the transmission line (20) to be analyzed and processed, and finally the signal is displayed through a display screen (3).

During detection of heavy metal components and content in gas, absorbed gas to be detected may not be measured because the concentration of the absorbed gas to be detected cannot reach the measurement standard of LIBS, so the purpose of measurement is achieved by changing the volume of the gas to be detected in the gas chamber (13), but the obtained measurement result is not the measurement result of the heavy metal components and content in the gas under the ordinary environment, and in order to obtain the heavy metal components and content in the gas under the ordinary environment, an ideal gas state equation is required to be introduced, namely the ideal gas state equation is required to be introduced, namely the ideal gas

After the gas collection is finished, the gas pressure P of the gas chamber (13) can be obtained through the gas pressure sensor (15) and the temperature sensor (6)₁And temperature T₁Volume V of gas to be measured₁After the collection is finished, the volume of the gas to be measured is changed until the LIBS measurement standard is reached, and the gas pressure P in the gas chamber (13) can be obtained through the gas pressure sensor (15) and the temperature sensor (6)₂And temperature T₂Thus, can be expressed by the formula

Obtaining the volume V of the gas to be measured when the LIBS measurement standard is reached₂When the console (4) obtains the data, the heavy metal components and the content of the gas in the normal environment can be obtained through an algorithm, and finally the heavy metal components and the content of the gas are displayed through the display screen (3).

The utility model has the advantages that: the device is convenient and simple for collecting gas. The whole set of device integrates collection, processing and detection, the collected gas sample can be immediately processed, the change of the detection environment can be conveniently completed, the sample can be measured at any time and any place, the volume, the temperature and the pressure of the gas and the data such as the measurement result obtained after measurement by utilizing the LIBS technology are observed through the display screen arranged on the console, the steps of gas collection, processing, detection and the like do not need to be separated, and the sample can be directly replaced after one-time measurement is finished to carry out the next measurement, so that the device has good continuity, and the efficiency in the measurement is further improved. The presence of the handle above the whole set of device can make the device portable and have good portability.

Drawings

Fig. 1 is a schematic structural view of the present invention;

fig. 2 is a top view of the present invention;

in the figure: 1-a gas collection and detection device; 2-a laser; 3-a display screen; 4-a console; 5-LIBS spectrum collection system; 6-temperature sensor; 7-a getter pump; 8-an exhaust pump; 9-a piston; 10-a piston rod; 11-a connecting rod; 12-a turntable; 13-air chamber; 14-a lens; 15-a barometric pressure sensor; 16-an aspiration channel; 17-an exhaust channel; 18-a handle; 19-control line one; 20-a transmission line; 21-control line two; 22-quartz window one; 23-quartz window two.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings:

as shown in fig. 1, this is a portable gas collection device that can be used for LIBS measurements, comprising a gas collection and detection device (1).

Specifically, the gas collection and detection device (1) comprises: the laser system comprises a gas chamber (13), a laser (2), a display screen (3), a console (4), an LIBS spectrum acquisition system (5), a temperature sensor (6), a getter pump (7), an exhaust pump (8), a piston (9), a piston rod (10), a connecting rod (11), a turntable (12), the gas chamber (13), a lens (14), an air pressure sensor (15), a getter channel (16), an exhaust channel (17), a handle (18), a first control line (19), a transmission line (20), a second control line (21), a first quartz window (22) and a second quartz window (23), wherein the getter channel (16) and the exhaust channel (17) can be opened or closed under the control of the console (4), the air pressure sensor (15) is positioned on the piston (9), the temperature sensor (6) is positioned at the top of the gas chamber (13), the laser (2) is positioned right above the whole gas chamber (13), the LIBS spectrum collection system (5) can receive a spectrum emitted by excited plasma after a sample in the gas chamber (13) is irradiated by exciting light, then the signal is transmitted to the console (4) through a transmission line (20), and the console (4) analyzes and processes the result and displays the result through the display screen (3). The piston (9) is connected with the piston rod (10), the piston rod (10) is connected with the connecting rod (11), the connecting rod (11) is connected with the rotary table (12), and the rotary table (12) can rotate under the control of the control console (4) through a control line II (21), so that the piston (9) and the piston rod (10) are controlled to move up and down, and the pressure in the air chamber (13) can be adjusted.

The specific use method is as follows:

when the device is in a measuring environment, the air suction channel (16) is opened under the control of the console (4) when a gas sample is collected, meanwhile, the exhaust channel (17) is also in an opened state but the exhaust pump (8) does not work, the exhaust channel (17) plays a role in balancing the air pressure in the air chamber (13) to prevent the gas sample to be measured from being sucked into the air chamber (13), before the gas to be measured is collected, the device can firstly discharge the air in the air chamber (13) to prevent the air from being mixed with the gas to be measured, the measurement result is influenced, after the air suction pump (7) is opened to absorb the external gas for a period of time, no other gas irrelevant to the gas to be measured exists in the air chamber (13), at the moment, the discharge process is finished, then the air suction pump (7) continues to work for a short period of time to finish the collection of the gas to be measured, and when the collection is finished, the display screen (3) can display the collection is used for displaying, and simultaneously, the suction pump (7) stops working, and the suction channel (16) and the exhaust channel (17) are closed to form a closed environment in the air chamber.

After the collection process is finished, because the gas concentration in the gas chamber (13) can not meet the LIBS measurement requirement, the control console (4) is used for controlling the rotary table (12) to rotate, the connecting rod (11) is driven to move, so that the piston rod (10) and the piston (9) are lifted, the volume of the gas to be measured is reduced, and the gas to be measured in the gas chamber (13) is enabled to be reducedWhen the gas concentration reaches the measurement standard of LIBS, the rotating disc stops rotating, but the change of the volume of the gas means the increase of the gas pressure and the increase of the temperature, and the measured result is not the content of heavy metal elements in the ordinary environment, and in order to convert the content of heavy metal elements in the gas when the gas concentration is measured to be the content of heavy metal elements in the gas in the ordinary environment, an ideal gas state equation is introduced, namely the ideal gas state equation is introduced

The air pressure P of the air chamber (13) can be obtained by the air pressure sensor (15) and the temperature sensor (6) before the volume of the gas to be measured is changed₁And temperature T₁The volume V of the gas to be measured is obtained when the gas collection is completed₁At the moment, the volume of the gas to be measured is controlled to start to change through the console (4), and when the environment in the gas chamber (13) reaches the measurement standard of the LIBS, the gas pressure P in the gas chamber (13) at the moment can be obtained through the gas pressure sensor (15) and the temperature sensor (6)₂And temperature T₂Thus, can be expressed by the formula

Obtaining the volume V of the gas to be measured when the LIBS measurement standard is reached₂。

When the environment in the gas chamber (13) reaches the measuring condition, the laser (2) emits laser under the control of the console (4), the laser is converged by the lens (14) and then emitted into the gas chamber (13) through the quartz window I (22) to strike the surface of the sample to generate plasma, the LIBS spectrum acquisition system (5) receives the spectrum emitted by the excited plasma, the obtained data is transmitted to the console (4) through the transmission line (20) to be analyzed and processed, and the obtained compressed volume V of the gas to be measured is used₂The measurement result under the ordinary environment is obtained through the algorithm, and the measurement of the heavy metal components in the gas and the content thereof is completed through the display (3) display.

After the measurement is finished, the rotary disc (12) can rotate under the control of the control console to drive the connecting rod (11) to move, the piston rod (10) and the piston (9) are controlled to descend until the rotary disc can reach the original position, the exhaust channel (17) is opened, the air suction channel (16) is in an opening state and the air suction pump (7) does not work, the air suction channel (16) plays a role in balancing the air pressure in the air chamber (13), the exhaust pump (8) starts to work, the air in the air chamber (13) is exhausted through the exhaust channel (17), when all the air is exhausted, the exhaust channel (17) and the air suction channel (16) are closed, and the whole air collection and detection process is finished. The collection and detection of the next gas sample can begin and the process can be repeated.

The gas collecting and detecting device (1) has continuity in detection of gas samples, is convenient and simple to operate, greatly improves detection efficiency, and the lifting handle (18) can be conveniently carried to improve portability.

Claims

1. A portable gas collecting device for LIBS measurement is characterized in that the gas collecting and detecting device integrates the collection, processing and detection of gas to be detected, can directly detect after the collection of a gas sample is finished, is of a cylindrical structure and consists of a gas collecting part, a gas processing part and a gas detecting part;

the gas collection portion includes: the air chamber (13), the air suction pump (7), the air suction channel (16), the exhaust pump (8), the exhaust channel (17), the console (4) and the display screen (3) are positioned in the center of the whole device;

the gas processing part comprises: the device comprises a piston (9), a piston rod (10), a connecting rod (11), a turntable (12), a temperature sensor (6), an air pressure sensor (15) and a second control line (21), wherein the temperature sensor (6) and the air pressure sensor (15) can transmit the real-time temperature and the real-time pressure in an air chamber (13) to a console (4), and then the real-time temperature and the real-time pressure are displayed through a display screen (3) on the console (4);

the gas detection section includes: the laser device comprises a laser device (2), a lens (14), a LIBS spectrum acquisition system (5), a control line I (19), a transmission line (20), a quartz window I (22) and a quartz window II (23), wherein the laser device (2) can emit laser under the control of a control console (4), the LIBS spectrum acquisition system (5) can receive light emitted by plasma and feed back the light to the spectrum acquisition system, the spectrum acquisition system transmits the obtained data to the control console (4) through the transmission line (20), and the result is displayed on a display screen (3) after the analysis processing.

2. A portable gas collection apparatus useful for LIBS measurements as claimed in claim 1 wherein: the suction passage (16) and the discharge passage (17) in the gas collecting section can be opened or closed under the control of the console (4), and the inside of the gas chamber (13) will be in a sealed state when both passages are closed at the same time.

3. A portable gas collection apparatus useful for LIBS measurements as claimed in claim 1 wherein: temperature sensor (6) in the gas processing part is located air chamber (13) top, baroceptor (15) are located on piston (9), piston (9) and piston rod (10) link together, piston rod (10) and connecting rod (11) link to each other, connecting rod (11) link to each other with carousel (12), carousel (12) can rotate under control of control cabinet (4) through control line two (21), thereby drive piston rod (10) and piston (9) and reciprocate, real-time temperature and atmospheric pressure in air chamber (13) can be shown in display screen (3).

4. A portable gas collection apparatus useful for LIBS measurements as claimed in claim 1 wherein: a quartz window I (22) in the gas detection part separates a gas chamber (13) and a laser (2) from a lens (14), a LIBS spectrum acquisition system (5) is covered by a quartz window II (23) to play a role in protection, the LIBS spectrum acquisition system (5) receives a spectrum emitted by excited plasma in the gas chamber, then transmits a signal to a control console (4) through a transmission line (20) for analysis and processing, and finally displays the signal through a display screen (3).

5. A portable gas collection apparatus useful for LIBS measurements as claimed in claim 1 wherein: a handle (18) is arranged at the top end of the whole device.