CN105738306A - Portable fire control emergency rescue multi-gas rapid remote sensor and detecting method - Google Patents

Abstract

The invention discloses a portable multi-gas rapid remote sensing instrument for fire emergency rescue, which includes an analysis system and a reflection system arranged on both sides of a detection area, and the analysis system includes a reflection mirror, a first collimator beam expander lens and a second collimator beam expander Lens, the analysis system also includes a receiving fiber optic head and a focusing lens, the receiving fiber optic head is connected to a spectrum analyzer and a computer in turn; the analysis system also includes a special ultraviolet light source. Detection method: the analysis system and the reflection system are set on both sides of the detection area; the special ultraviolet light source is turned on, converged to the first collimator beam expander lens through the reflector, and the ultraviolet beam is output through the second collimation beam expander lens, and then passes through the reflection system to the The focusing lens converges to the receiving optical fiber head; it is sent to the spectrum analyzer to calculate the absorption intensity and absorption wavelength; it is transmitted to the computer to calculate the gas composition and concentration; a reference rescue implementation plan is given. The invention realizes rapid, non-contact and large-scale detection of toxic and harmful gas components and concentrations.

Description

Portable fire emergency rescue multi-gas rapid remote sensing instrument and detection method

technical field

The invention relates to a remote sensing instrument and a detection method, more specifically, to a portable multi-gas rapid remote sensing instrument for fire emergency rescue and a detection method.

Background technique

Today, with the rapid development of science and technology, new petrochemical products and materials emerge in an endless stream, with increasing varieties and expanding application scope, which greatly improves and improves people's living standards, but at the same time leads to an increase in hazardous chemical disasters. Hazardous chemical disaster accidents refer to the leakage of hazardous chemicals caused by people’s production, transportation, storage, and use of hazardous chemicals due to reasons such as design defects, illegal operations, and equipment failures, resulting in environmental pollution, combustion explosions, Accidents with serious consequences such as casualties. And due to the characteristics of hazardous chemicals such as easy evaporation and low boiling point, there are a lot of toxic and harmful gases at the accident site. The public security fire brigade undertakes fire fighting, major disaster accidents and other emergency rescue work mainly to save people's lives. Due to the wide variety of petrochemical products with different physical and chemical properties, the disposal methods and procedures of different chemical disasters are also different. However, there are basically a large amount of toxic and harmful gases at the scene of a hazardous chemical leakage accident. Emergency rescue of hazardous chemical disaster accidents has a high risk. When fire officers and soldiers participate in the rescue of chemical disaster accidents, a slight mistake may easily cause self-injury. According to the analysis and research of 25 firefighting officers and soldiers who caused their own casualties in the rescue of hazardous chemical disaster accidents in recent years, the average probability of firefighters dying in emergency rescue of hazardous chemical disaster accidents is the same as that of firefighting and rescue, social assistance and other rescues. Actions are 1,120,000 times, and the probability of injury is 3,386,667 times that of rescue operations such as fire fighting and rescue and social assistance. In these cases, sudden poisonous and harmful gas explosion accidents often occur, and in the cases of firefighter casualties caused by toxic and harmful gas explosion accidents, more than 70% of cases are not properly investigated. Inadequate detection is mainly manifested in the inability to identify the components of toxic and harmful gases at the accident site, or the inability to measure the concentration of the identified toxic and harmful gases. Safety precautions, panic response when toxic and harmful gas leaks, resulting in relatively large casualties of firefighters at the scene. How to detect the composition and concentration of various toxic and harmful gases in hazardous chemical disasters as soon as possible without contact is an urgent problem for fire departments to solve in accident rescue.

At present, most of the portable gas detection instruments in domestic and foreign fire rescue equipment use electrochemical sensors, which can detect 1-6 types of gases at the same time. Compared with other types of gas sensors, electrochemical sensors are small in size, low in power consumption, and repeatable It has better performance and longer service life, and is a relatively common detection element for detecting toxic and harmful gases in fire rescue. However, there are relatively few detectable types, low sensitivity and other disadvantages, and long-distance (non-contact) detection cannot be realized. On May 18, 2006, a series of car collisions occurred in Yichang Zhijiang section of Hanyi Expressway in Yichang City, Hubei Province, resulting in the leakage of a tank truck containing dimethyl sulfate [(CH3)2SO4], killing 5 people Dead, 12 injured and 44 poisoned. The firefighters who participated in the rescue at the scene used the toxic gas and flammable gas detectors equipped by the firefighting force to detect for many times, but they could not find out the name, concentration and hazard characteristics of the leaked substances at the scene, resulting in poisoning and injury to 5 firefighters during the accident disposal. Some well-known foreign manufacturers (such as American Scientific Corporation) vigorously develop portable gas detection instruments, and use advanced technologies such as wireless network transmission to realize real-time detection of six gases; in order to adapt to the detection of multiple gases, some domestic and foreign manufacturers have carried out portable infrared spectroscopy. The detection instrument can detect hundreds of gas components at the same time according to the database analysis. At the same time, portable gas chromatography, gas detection tube and other detection technologies are also widely used in gas detection equipment. The common disadvantage of these fire-fighting and rescue gas detection equipment is that they all have to enter the dangerous chemical leakage area for detection, which undoubtedly increases the danger of rescuers. At the same time, in these detection equipment, except for the simple electrochemical detection method, most other detection technologies such as infrared spectroscopy require specialized technology and experience to operate, which undoubtedly increases maintenance costs. The maintenance and use of the equipment increases the difficulty of the fire brigade. Due to the low boiling point and high volatility of the leaked chemicals, some of them are gases at normal temperature and pressure, and quickly form a high-concentration aerosol cluster after leakage. When there is wind, they will quickly spread with the wind direction. Due to the characteristics of strong suddenness and fast diffusion, the emergency rescue command personnel must grasp the diffusion distribution of the entire leakage area in real time and dynamically, so as to adjust the rescue plan at any time. Monitoring and detection of the entire area cannot be achieved.

To sum up, the qualitative and quantitative detection of toxic and harmful gases in hazardous chemical disasters is extremely important in the field of fire rescue. At present, no one has proposed a non-contact multi-gas composition and concentration gas detection equipment, and the current gas composition detection equipment can only detect a small point range around the person carrying it, which cannot meet the needs of fire rescue. It can be seen from this that the design A non-contact multi-gas composition and concentration portable gas detection device and method are currently in urgent need of equipment for reducing casualties of firefighting forces and improving firefighting and rescue combat effectiveness.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies in the prior art, provide a portable multi-gas rapid remote sensing instrument for fire emergency rescue and detection method, and use differential optical absorption spectroscopy technology to realize rapid detection of toxic and harmful gas components and concentrations at the accident site , non-contact, large-scale detection.

The purpose of the present invention is achieved through the following technical solutions.

The portable multi-gas rapid remote sensing instrument for fire emergency rescue of the present invention includes an analysis system and a reflection system arranged on the left and right sides of the detection area, and the analysis system includes a reflection mirror and a first collimating beam expander lens arranged in sequence from left to right and the second collimating beam expander lens, the reflector, the first collimating beam expander lens, the second collimating beam expander lens and the reflection system beam incident part are on the same optical path, and the analysis system also includes from left to The receiving fiber optic head and the focusing lens arranged on the right, the receiving fiber optic head, the focusing lens and the beam exit part of the reflection system are on the same optical path, and the receiving fiber optic head is connected with a spectrum analyzer and a computer in sequence; the analysis system also includes Ultraviolet special light source; the detection area is located between the outgoing light path of the second collimating beam expander lens and the incident light path of the reflection system.

The reflection system is composed of corner cube prisms.

The reflector is a parabolic reflector.

The detection method of the above-mentioned portable multi-gas rapid remote sensing instrument for fire emergency rescue comprises the following steps:

(1) Estimate the scope of the detection area, and set the analysis system and reflection system on both sides of the detection area;

(2) Turn on the special ultraviolet light source to emit ultraviolet light, the ultraviolet light is converged to the first collimator beam expander lens through the reflector, and the uniform ultraviolet beam with uniform direction is output by the second collimator beam expander lens, and the ultraviolet beam passes through The detection area is reflected to the focusing lens by the reflection system, and converges to the receiving fiber head through the focusing lens;

(3) sending the ultraviolet light beam received by the receiving optical fiber head into the spectrum analyzer in step (2), and calculating the absorption intensity and the absorption wavelength;

(4) The absorption intensity calculated in the step (3) and the absorption wavelength are transmitted to the computer with an electric signal, and the gas composition and concentration are calculated by using the neural network model analysis calculation software, and displayed;

(5) Identify the degree of danger based on the gas composition and concentration detected in step (4), and provide a reference rescue implementation plan.

The establishment of neural network model analysis calculation software in described step (4), comprises the following steps: establish the ultraviolet absorption spectrum database of many dangerous gases and the dangerous degree prediction database of many dangerous gases; Utilize the method of wavelet analysis and Lambert-Beer's law, establish Neural network model analysis and calculation software with self-learning function.

Compared with the prior art, the beneficial effects brought by the technical solution of the present invention are:

(1) In the present invention, the ultraviolet special light source is used as the light source of the system differential absorption spectroscopy technology, which has the characteristics of high stability, long life, wide wavelength range, etc., and meets the design requirements;

(2) In the present invention, the reflection mirror, the first collimation beam expander lens, the second collimation beam expander lens and the reflective system light beam incident part are on the same optical path, the reflection mirror can improve the system signal strength, and the first collimation beam expander lens The beam lens and the second collimating beam expander lens can shape the converged ultraviolet light into a uniform ultraviolet light beam with uniform directionality;

(3) In the present invention, the analysis system and reflection system are arranged on both sides of the detection area, and a non-contact remote sensing method is adopted to avoid the contact of detection personnel with toxic and harmful gases, and greatly increase the scope of the detection area.

Description of drawings

Fig. 1 is a structural schematic diagram of the present invention.

Reference signs: 1 analysis system; 2 reflection system; 3 detection area; 11 reflector; 12 first collimator beam expander lens; 13 second collimator beam expander lens; 14 special ultraviolet light source; 15 focusing lens; head; 17 spectrum analyzer; 18 computer; 21 corner cube prism.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, the portable multi-gas rapid remote sensing instrument for fire emergency rescue of the present invention includes an analysis system 1 and a reflection system 2 arranged on the left and right sides of the detection area 3, and the reflection system 2 is a passive device to realize the detection of ultraviolet For the exact reverse function of the light beam, the reflective system 2 is composed of a corner cube prism 21 . The analysis system 1 includes a reflector 11, a first collimating beam expander lens 12 and a second collimating beam expander lens 13 arranged in sequence from left to right, the reflector 11 is provided with a paraboloid, and the reflector 11, The first collimator beam expander lens 12 , the second collimator beam expander lens 13 and the beam incident part of the reflection system 2 are on the same optical path. The analysis system 1 also includes a receiving fiber head 16 and a focusing lens 15 arranged from left to right, and the receiving fiber head 16 , focusing lens 15 and the beam output part of the reflection system 2 are on the same optical path. The receiving optical fiber head 16 can be connected to the input end of the spectrum analyzer 17 through an optical fiber, and the output end of the spectrum analyzer 17 is connected to a computer 18 . The detection area 3 is only located between the outgoing light path of the second collimating beam expander lens 13 and the incident light path of the reflection system 2 . A light source is arranged near the reflector 11, and the light source can be a special ultraviolet light source 14.

The main function of the analysis system 1 is to emit and receive ultraviolet light beams, analyze the ultraviolet light beams containing gas information and output the results. The special ultraviolet light source 14, as the light source of the system differential absorption spectroscopy technology, has the characteristics of high stability, long life, wide wavelength range, etc., and meets the design requirements. The reflector 11 is used to converge the scattered ultraviolet light emitted by the special ultraviolet light source 14 to the first collimating beam expander lens 12, so as to improve the signal intensity of the system. The first collimator beam expander lens 12 and the second collimator beam expander lens 13 are used to shape the ultraviolet light converged by the mirror 11 into a uniform ultraviolet beam with uniform directionality for detection. The focusing lens 15 is used for converging the reverse ultraviolet light beam with gas information reflected by the reflection system 2 so as to be received by the receiving optical fiber head 16 . Described receiving optical fiber head 16 is connected with optical fiber, is used for receiving the reverse ultraviolet light that is converged by focusing lens 15, and ultraviolet light is sent into optical fiber, and described optical fiber is connected with spectrum analyzer 17 input ends, adopts single-mode optical fiber, uses The reverse ultraviolet light with gas information is sent to the spectrum analyzer 17. The output end of the spectrum analyzer 17 is connected to a computer 18 for analyzing reverse ultraviolet light and extracting the absorption intensity and absorption wavelength with gas information. The computer 18 is used to analyze and calculate the extracted absorption intensity and absorption wavelength, obtain the gas composition and concentration results, and display them. The reflection system 2 is used to reflect the ultraviolet beam passing through the detection area 3 back to the analysis system 1 . The corner cube prism 21 is used to reflect the ultraviolet beam.

The detection method of the above-mentioned portable multi-gas rapid remote sensing instrument for fire emergency rescue comprises the following steps:

(1) Estimate the scope of the detection area 3 (that is, the diffusion range of toxic and harmful gases at the accident site), determine the danger zone, and set the analysis system 1 and the reflection system 2 on both sides of the detection area 3 respectively. Turn on the power, and use the target indicating unit to align the analysis system 1 and the reflection system 2. The target indication unit adopts a domestic infrared and visible target indication and control unit for the analysis system 1 and the reflection system 2. Alignment can eliminate the complex and harsh conditions on site, accurately align the reflective system 2, and adjust the analysis system 1 and reflective system 2 to the best measurement state according to the obtained reflected infrared indicator signal spectrum.

(2) Close the target indicating unit, turn on the special ultraviolet light source 14 for detection, the special ultraviolet light source 14 emits ultraviolet light, and the ultraviolet light converges to the first collimating beam expanding lens 12 through the reflecting mirror 11, and then passes through the second collimating and expanding lens. The beam lens 13 outputs a uniform ultraviolet light beam with a uniform direction, and the ultraviolet light beam passes through the detection area 3. According to the absorption phenomenon of the electromagnetic radiation by the substance, the absorption characteristic of the substance is related to the energy of the radiation, and the absorption of each substance for the radiation is It is characteristic. That is, each substance has its own characteristic absorption spectrum, and the absorption intensity is related to the concentration of the substance. Therefore, the ultraviolet light beam passing through the detection area 3 will contain the characteristic absorption wavelength and absorption intensity information of the gas. The ultraviolet light beam containing gas information is reflected back to the analysis system 1 through the reflection system 2, and converged to the receiving optical fiber head 16 through the focusing lens 15.

(3) The ultraviolet light beam received by the receiving optical fiber head 16 is sent to the spectrum analyzer 17 through the optical fiber, and the absorption intensity and absorption wavelength are calculated by the spectrum analyzer 17 .

(4) The spectrum analyzer 17 transmits the calculated absorption intensity and absorption wavelength to the computer 18 as an electrical signal, uses the neural network model analysis and calculation software to calculate the gas composition and concentration, and displays it through the display terminal. The establishment of the neural network model analysis calculation software includes the following steps: establishing an ultraviolet absorption spectrum database and a multi-hazardous gas hazard degree prediction database in the computer; utilizing wavelet analysis methods and Lambert-Beer law to establish a Neural network model analysis and calculation software for learning functions. The gas composition and concentration analysis and calculation steps: the first step is to extract the differential absorption spectrum from the original absolute absorption spectrum, use the best fitting method to fit the absorption peak, determine the initial value of the first dangerous gas, and then start from the original Remove the spectral line of the first fitting from the spectrum; in the second step, use the same method as the first step to fit the spectral line of the second dangerous gas to determine the initial value of the second dangerous gas, and then Remove the second fitted spectral line from the original spectrum; loop in turn to obtain the spectral line of the i-th dangerous gas. The gas concentration was then calculated using the Lambert-Beer law.

(5) According to the established multi-hazardous gas hazard degree prediction database, the hazard degree of the detected gas composition and concentration is identified, and a reference rescue implementation plan is given.

According to the Lambert-Beer law, the relationship between the light intensity of light of a certain wavelength before and after passing through the gas with selective absorption characteristics is:

$\mathrm{<span\; class="notranslate">\; I</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&lambda;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; I</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&lambda;</span>}<span\; class="notranslate">\; )</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}\mathrm{<span\; class="notranslate">\; C</span>}\mathrm{<span\; class="notranslate">\; L</span>}}$

in:

I(λ): the light intensity of ultraviolet light with a wavelength of λ absorbed by the gas;

I ₀ (λ): the light intensity of ultraviolet light with a wavelength of λ before it is absorbed by the gas;

α _λ : Gas absorption coefficient of ultraviolet light with wavelength λ;

C: gas concentration;

L: The length of the ultraviolet light passing through the absorbing gas.

Therefore, if I(λ), I ₀ (λ), α _λ and L are known, the gas concentration can be calculated. By comparing the known characteristic absorption wavelengths of different gases, the composition of the gas can be identified, and finally the analysis and calculation The gas composition and concentration are displayed.

The indicators that the present invention can achieve: detection range: 0-100m; accuracy: ±10%; response speed: <10s; dangerous gases that can be measured: ammonia, benzene, toluene, xylene, carbon disulfide, formaldehyde, hydrogen sulfide, a Nitrogen oxide, nitrogen dioxide, sulfur dioxide, etc.

Claims (5)

1. A portable multi-gas remote sensing instrument for fire emergency rescue is characterized in that it includes an analysis system and a reflection system arranged on the left and right sides of the detection area, and the analysis system includes reflectors arranged in turn from left to right, a first The collimating beam expanding lens and the second collimating beam expanding lens, the reflector, the first collimating beam expanding lens, the second collimating beam expanding lens and the beam incident part of the reflection system are on the same optical path, and the analysis system It also includes a receiving optical fiber head and a focusing lens arranged from left to right, the receiving optical fiber head, focusing lens and the beam exit part of the reflection system are on the same optical path, and the receiving optical fiber head is connected with a spectrum analyzer and a computer in sequence; The analysis system also includes a special ultraviolet light source; the detection area is located between the outgoing light path of the second collimating beam expander lens and the incident light path of the reflection system. 2. The portable multi-gas rapid remote sensing instrument for fire emergency rescue according to claim 1, wherein the reflection system is composed of a corner cube. 3. The portable multi-gas rapid remote sensing instrument for fire emergency rescue according to claim 1, wherein the reflector is a parabolic reflector. 4. a detection method of the above-mentioned portable fire emergency rescue multi-gas fast remote sensing instrument, is characterized in that, comprises the following steps: (1) Estimate the scope of the detection area, and set the analysis system and reflection system on both sides of the detection area; (2) Turn on the special ultraviolet light source to emit ultraviolet light, the ultraviolet light is converged to the first collimator beam expander lens through the reflector, and the uniform ultraviolet beam with uniform direction is output by the second collimator beam expander lens, and the ultraviolet beam passes through The detection area is reflected to the focusing lens by the reflection system, and converges to the receiving fiber head through the focusing lens; (3) sending the ultraviolet light beam received by the receiving optical fiber head into the spectrum analyzer in step (2), and calculating the absorption intensity and the absorption wavelength; (4) The absorption intensity and the absorption wavelength calculated in the step (3) are transmitted to the computer with an electric signal, and the gas composition and concentration are calculated by using the neural network model analysis calculation software, and displayed; (5) Identify the degree of danger based on the gas composition and concentration detected in step (4), and provide a reference rescue implementation plan. 5. the detection method of portable fire-fighting emergency rescue multi-gas fast remote sensing instrument according to claim 4, is characterized in that, the establishment of neural network model analysis calculation software in described step (4), comprises the following steps: set up multi-dangerous gas The ultraviolet absorption spectrum database and the multi-hazardous gas hazard degree prediction database; using the wavelet analysis method and the Lambert-Beer law, establish a neural network model analysis and calculation software with self-learning function.