Electronic nose instrument for fixed stool and movable stool and multi-component online real-time detection method for stink

Abstract

The invention provides an electronic nose instrument for fixed stool and movable stool and an online real-time detection method for odor pollutants. The instrument mainframe box is mainly formed by a gas sensor array module, a gas headspace sampling module, a pressure multiplication module and a computer control and analysis module, and auxiliary parts are a clean air bottle and an alternating current and direct current mobile power supply. Within the period T = 180-600s, the pressure intensity in the working cavity of the gas sensitive sensor array is doubled by the pressurizing cylinder in a short time, and the response of 16 gas sensitive sensors is obviously increased; and the computer control and analysis module selects three components including a steady-state peak value, peak appearance time and an area under the curve from each response curve according to a triangular stability principle, and adds environment temperature and humidity values to obtain a 3 * 16 + 2 = 50-dimensional gas-sensitive sensing sample. Fixed or mobile detection, indoor or field detection and on-line or real-time detection of stink pollution are achieved through the fixed and live dual-purpose electronic nose instrument, a big data set is established, and then a new machine learning model is used for achieving on-line real-time analysis of multiple indexes of stink.

Description

Technical Field

[0001] The present invention - a fixed-term or live-terminal electronic nose instrument and a method for online real-time detection of multiple components of odor are based on GB14554 "Emission Standard of Odor Pollutants" (draft for comments) promulgated by the Ministry of Ecology and Environment on December 3, 2018, and are aimed at the monitoring and analysis needs of odor pollution status in chemical parks, landfills, sewage treatment plants, livestock and poultry farms, and adjacent residential areas. It involves scientific and technological fields such as artificial intelligence, computers, and ecological environment, and mainly solves the problems of existing electronic nose instruments with unsatisfactory sensitivity and selectivity, poor online and real-time applicability, and single use, so as to flexibly realize continuous online or on-site real-time detection of multiple components of odor pollutants. Background Art

[0002] Green environmental protection industry is a national emerging industry. We will establish a modern ecological environment monitoring system, focus on solving the pollution problems such as odor and restaurant fume, study the online monitoring and impact assessment technology of atmospheric odor pollution, and implement the " Double random The "one disclosure, one public" supervision model will be adopted to strengthen monitoring capacity building, achieve full coverage of environmental quality, pollution sources and ecological status monitoring, and promote Monitoring equipment Accurate, fast and portable Development, ensuring monitoring data" True, accurate and complete ", comprehensively improving the level of monitoring automation, standardization and informatization, which are the important starting points of this invention.

[0003] "Odor" is also called "smell", which is the abbreviation of "odor pollutant", specifically referring to unpleasant odor, and generally refers to all gaseous substances that stimulate the olfactory organs and cause people to feel unpleasant and damage the living environment. Odor pollutants are widely present in the atmospheric environment of biochemical and pharmaceutical, garbage and sewage treatment, livestock and poultry breeding and other enterprises as well as adjacent residential areas, and are widely distributed. One of the current situations of odor / smell pollution in my country is that there are many emission sources, the odor components are complex, the national standards are lagging behind, residents complain frequently, and casualties occur from time to time. For many years, the proportion of environmental complaints has been greater than 20%, becoming the second largest source of environmental complaints; the second situation is that the "national standard" is reached but the "civilian standard" is not reached, that is, the measurement results of the monitoring agency meet the standards, but the residents cannot tolerate it, and complaints continue. Odor is an environmental hazard that seriously disturbs the people and endangers their health. The current "Environmental Protection Law" of the country lists it as one of the seven major pollutants to be prevented and controlled, and the control of odor pollution has been continuously included in the national environmental protection plan.

[0004] GB14554 "Emission Standards for Odor Pollutants" (draft for comments) published by the Ministry of Ecology and Environment on December 3, 2018 stipulates that the emission control indicators for odor pollutants are composed of 8 single component concentrations, including hydrogen sulfide H2S, ammonia NH3, methyl mercaptan CH4S, dimethyl disulfide C2H6S2, methyl sulfide C2H6S, carbon disulfide CS2, trimethylamine C3H9N, styrene C8H8, and 1 overall odor concentration, that is, 8+1 quantitative indicators. GB14554-1993 has been implemented for 31 years and is no longer able to adapt to the current odor pollution problem. However, the new standard has not been officially promulgated and implemented, indicating that the qualitative and quantitative analysis of odor pollution is very complicated. Many experts have called for the revision of standards, the improvement of quality, emission, monitoring and other standards, and the construction of a standard system for odor prevention and control.

[0005] GB14554, both the current and new standards (draft for comments), stipulate that the three-point comparison odor bag method is used to determine the odor concentration, the gas chromatography method is used to determine the concentration of H2S, CH4S, C2H6S, C2H6S2, C3H9N and C8H8, and the spectrophotometry method is used to determine the concentration of NH3 and CS2. According to the industry standard HJ1262-2022 "Ambient air and waste gas - Determination of odor - Three-point comparison odor bag method" implemented in 2023, "odor concentration" is Odor Room Use odorless clean air On-site collection The dilution factor of the odor sample when it is continuously diluted to the olfactory threshold of the odor detector; the EU standard EN17325-2003 uses the OU (odor unit) value for measurement. HJ1262 regulates the selection of odor detectors, sample collection, manual dilution, and manual olfactory identification.

[0006] The dilemma of the sensory measurement method of "odor concentration" is that many odorous substances either have no olfactory threshold at all, or the values ​​given by different countries, regions or organizations vary greatly. "The right or wrong choice depends entirely on the subjective judgment of the odorist after sniffing" [1]. In 2015, the Tianjin "National Environmental Protection Odor Pollution Control Key Laboratory" organized 30 odorists (13 men and 17 women) to measure the olfactory thresholds of 40 odorous substances [1]. The olfactory threshold of NH3 in Tianjin differed by 5 times from that in Japan, the H2S value differed by nearly 3 times, the trimethylamine value differed by 28.12 times, and the n-valeric acid value differed by as much as 65.67 times, etc. These facts indicate at least two problems: (1) the sensory measurement process of odor concentration is complicated, time-consuming and labor-intensive; (2) the olfactory threshold is poorly consistent and not objective. The human sense of smell can detect more than 4,000 odor-causing components, and odors often contain dozens or hundreds of them, and dozens of them are more harmful to health. The olfactory method is harmful to health, and conventional instrumental methods such as chromatography have complex operating procedures and harsh testing conditions; the common shortcomings of the two are high cost, low efficiency, and poor real-time performance. Therefore, machine olfactory methods and instruments are particularly attractive.

[0007] Online real-time monitoring, estimation and prediction of 8+1 concentration indicators of odor pollutants are the basic requirements for smart city construction, indicating the urgency of industrial application of machine olfaction theory and technology. The cruel reality is that the research on machine olfaction, which began in the early 1960s and emerged in the 1980s, is still in the laboratory stage as a whole, is not yet mature, and has almost no industrial application. For example, the French FOX Odor Fingerprint Analyzer entered the Chinese market in 2007, with a price of up to $150,000, or more than 1 million RMB. It is only used for offline laboratory detection and cannot be used for online real-time detection of odor on-site. The parent company has discontinued its production and withdrawn from the Chinese market.

[0008] Machine olfactory system Initially seen as a combination of multiple overlapping capabilities Gas Sensor of Array and appropriate model Identification method Composition An instrument ,able Identifying simple and complex smells , now more emphasis is placed on being an odor measurement and analysis Ability (odor measurement and analysis capability). Unfortunately, the research on machine olfaction, which lasted for more than 60 years, is still confined to the laboratory. Typical gas-sensitive materials include MOS, electrochemical (EC), conducting polymer (CP), quartz microbalance (QMB), surface acoustic wave (SAW) and photoionization detector (PID). Taking into account the sensitivity, response speed, degree of commercialization, life, size, simplicity, stability and other factors, MOS gas sensors represented by SnO2 are the most widely used. This invention takes this as the basis for the development of odor electronic nose instruments.

[0009] The research on machine olfaction should be based on ① revealing the mechanism of olfactory perception and ② Gas sensor array and Machine Learning method As the starting point, with ③ industrial application as the guide, the three are interdependent and cannot be neglected, otherwise it will fall into misunderstanding. For example, what is the microscopic perception mechanism of MOS gas-sensitive materials represented by SnO2? From the perspective of material properties alone, there is a grain interface. Potential Barrier Change, Surface Space Charge There is no definitive conclusion on the theory of change. If we study the perception mechanism with industrial application as the guide, we will discover new horizons.

[0010] here, Live real time - One-time or limited detection and analysis of odor or volatile gas of source substances on site, test as soon as they arrive, test as soon as samples are prepared, and the detection and analysis cycle of one time is 5-10 minutes; Continuous online —Continuous and multiple detection and analysis of malodorous gases on site, with a detection and analysis cycle of 5-10 minutes.

[0011] The working mode and performance level of existing odor monitoring devices are far from the principle of "random, accurate, complete, portable and fast". What are the key scientific issues and technical bottlenecks of electronic noses for odor detection and analysis applications? First, there is no research from the perspective of the complex odor composition characteristics of odor, and laboratory research is disconnected from application; second, there is no research oriented towards industrial applications, resulting in the olfactory simulation method not being able to leave the laboratory. In order to use olfactory simulation technology for online real-time detection of odor pollutants, we must solve the following scientific and technological problems:

[0012] (A) Typical application-oriented gas sensing mechanism revelation, concentration enhancement and information selection issues

[0013] There is a tendency for the theory and practice to be out of touch in the research of gas sensing mechanism. On the one hand, material researchers are striving to find more sensitive gas sensing materials and develop more advanced manufacturing processes; on the other hand, there are so many gas compounds that it is too arbitrary to draw conclusions about whether a material is sensitive or not based on laboratory tests of a limited number of compounds. Therefore, it is particularly important to study the gas sensing mechanism with an application-oriented approach.

[0014] The characteristics of complex odors are: (i) they have many and varied components. Except for a few inorganic substances such as H2S and NH3, most of them are organic substances, namely "volatile organic compounds (VOC)". (ii) Some compounds have a very low olfactory threshold, but contribute greatly to the odor intensity; vice versa. (iii) Some compounds contribute very little to the odor intensity, but the gas sensor is very sensitive, and vice versa. Therefore, when it is known that a material has good sensitivity, it is more important to focus on the specific application objects and application conditions to carry out research.

[0015] From the perspective of instrument design and industrial application, this study studies how to draw on the existing gas pre-concentration technology and the Langnuir adsorption and desorption principle to increase the pressure in a short period of time so that more trace odor molecules can be adsorbed on the surface of the sensitive membrane, thereby achieving the purpose of improving the sensitivity of gas sensors.

[0016] (B) Combination optimization of multiple working parameters of machine olfactory system and online real-time industrial application problems

[0017] This application project is guided by the urgent need for instruments to replace manual work in the field of odor analysis, problem-oriented to improve the multi-parameter intelligent analysis capabilities of machine olfactory systems, and goal-oriented to achieve industrial applications of online real-time analysis of multiple indicators of complex odors.

[0018] One of the scientific and technological problems that need to be solved here is: from the perspective of machine olfactory system design and industrial application, simulate the human breathing method, study how to optimize the combination of working parameters such as sample volume, volatile gas capacity, injection flow, pressure, temperature, and duration, and use sensitive membranes characterized by large sample volume and large injection flow to quickly cycle adsorption and desorption of complex odors, and use internal precision "unchanging" to cope with external "ever-changing", both online and real-time, fixed and mobile, and indoor and outdoor, to achieve the goal of significantly improving gas sensitivity and repeatability.

[0019] References

[0020] [1] Wang Weng, Zhai Zengxiu, Geng Jing, et al., Determination of olfactory thresholds of 40 typical malodorous substances, Journal of Safety and Environment, 2015, 15(6): 348–351. Summary of the invention

[0021] The present invention is based on the existing invention patents "A system and method for multi-point centralized online monitoring and analysis of malodorous gases" (see patent application number: 2018104716131) and "Big data driven multi-point centralized electronic nose instrument online analysis method for malodorous gases" (see patent application number: 2018104717083), and invents a fixed-point and movable electronic nose instrument and a multi-component online real-time detection and analysis method for malodors, so as to solve the problem of on-site or long-term continuous online monitoring or short-term real-time detection of malodor pollution, and realize the online real-time quantitative estimation and prediction of the 8+1 malodor pollutant concentration control index values ​​specified in GB14554.

[0022] In order to achieve the above object, the present invention provides the following technical solutions:

[0023] The hardware of the electronic nose instrument includes a gas sensor array module I, a gas automatic headspace sampling module II, a pressurized cylinder III, a computer control and analysis module IV, a backup power supply V, and a clean air bottle VI; among them, the gas sensor array module I, the gas automatic headspace sampling module II, the pressurized cylinder III, and the computer control and analysis module IV constitute the main box; the electronic nose instrument can flexibly realize fixed or mobile detection of odor pollution on site, identification of odor types, and quantitative estimation and prediction of the concentration of multiple odorous compounds;

[0024] The gas sensor array module I includes: a gas sensor array I-1, a gas sensor array annular working chamber I-2, a heat insulation layer I-3, a partition I-4, a fan I-5, a resistance heating wire I-6, and a temperature sensor I-7, which is located in the upper right part of the electronic nose instrument main box. The environmental temperature and humidity sensor I-8 is located in the upper right corner of the front inner wall of the electronic nose instrument main box.

[0025] The gas automatic headspace sampling gas path module II includes: a micro vacuum pump II-1, a flow meter II-2, a throttle valve II-3, a first two-position two-way solenoid valve II-4, a second two-position two-way solenoid valve II-5, a third two-position two-way solenoid valve II-6, a fourth two-position two-way solenoid valve II-7, a fifth two-position two-way solenoid valve II-8, and a purifier II-9. The booster cylinder III includes: a piston III-1, a piston rod III-2, a cylinder body III-3, a compression spring III-4, an O-ring III-5, an inner retaining ring III-6, a front cover III-7, and an anti-collision pad III-8. The gas automatic headspace sampling gas path module II and the booster cylinder III are located at the lower right in the main box of the electronic nose instrument.

[0026] The main components of the computer control and analysis module IV include: A / D data acquisition card IV-1, drive and control circuit board IV-2, computer mainboard IV-3, 4-way precision DC regulated power supply IV-4, WIFI board IV-5, touch screen IV-6, which are located on the left side of the main box of the electronic nose instrument.

[0027] Clean air bottles VI include: 40L large clean air bottle VI-1 and 2-6L small clean air bottle VI-2. The 40L large clean air bottle VI-1 is mainly used for long-term continuous online detection of odor sites for more than 2 hours; the 2-6L small clean air bottle VI-2 is used for limited short-term real-time detection of odor sites within 0.5-6 hours.

[0028] The Dinghuo two-hand electronic nose instrument forms a large odor data set X through long-term continuous online detection or short-term multiple detection of various odor pollution sites. The machine learning model learns from this data set to master the correspondence between the gas sensor array response and 8 single components and 1 overall odor concentration control indicators, including hydrogen sulfide H2S, ammonia NH3, methyl mercaptan CH4S, dimethyl disulfide C2H6S2, methyl sulfide C2H6S, carbon disulfide CS2, trimethylamine C3H9N, and styrene C8H8, namely 8+1 odor pollutant concentration control indicators, and determines the odor pollution type based on this in the decision-making stage, and estimates and predicts the 8+1 odor pollutant concentration control indicator values ​​online in real time.

[0029] The gas sensor array I-1 and its annular working chamber I-2 are located in a constant temperature room at 55±0.1℃; within the default value of the gas sampling cycle T=300s, depending on the type and flow of the gas, the gas sensor array I-1 and its annular working chamber I-2 go through the following five stages in sequence: ① Accurate calibration: Under the action of 1,000ml / min clean air purge, the gas sensor array I-1 gradually and accurately recovers to the standard state, which takes 60s. ② Balance: There is no gas flow in the annular working chamber I-2 of the gas sensor array, which takes 10s. ③ Headspace sampling: Under the suction action of the micro vacuum pump II-1, the gas sensor array I-1 responds sensitively to the 1,000ml / min malodorous gas being measured, which takes 30s. ④ Pressure doubling: Under the thrust of 0.2Mpa clean air, 78ml of malodorous gas in the booster cylinder III is pressed back to the annular working chamber I-2 of the gas sensor array. The pressure in the chamber increases by about 1 times in a short time, and the sensitive response of the gas sensor array I-1 is further increased, which lasts for 30s. ⑤ Exhaust gas emission: Under the suction of the micro vacuum pump II-1, the exhaust gas from the annular working chamber I-2 of the gas sensor array, the booster cylinder III and the related air pipelines is discharged into the atmosphere, which lasts for 170s. As the malodorous exhaust gas is discharged, the gas sensor array I-1 gradually returns to its initial state. If the gas injection cycle T>300s, the exhaust gas emission time will be extended accordingly, and the flow rate and duration of the other four stages will remain unchanged; for example, if T=480s, the exhaust gas emission time length is 170+(480-300)=350s; if T<300s, the exhaust gas emission time length is 170+(T-300)<170s.

[0030] According to the ideal gas state equation under constant temperature conditions p1V1=p2V2 and the classical Langmuir isothermal low-pressure adsorption equation q=γpq m / (1+γp), where p1, p2 and p are pressures, V1 and V2 are volumes, q is the adsorption amount, q mis the saturated adsorption amount, γ is the equilibrium constant, and the present invention uses the boost cylinder III to achieve an increase in the adsorption amount of trace components as the pressure increases. The specific measures are: designing a small-volume and small-section gas sensor array annular working chamber I-2 with a middle diameter of φ140mm and two cross-sectional sizes of 14×10mm and 16×20mm, and a net volume of 75ml; designing a one-way introduction ultra-thin piston boost cylinder III, the diameter of the piston III-1, i.e. the cylinder diameter, is φ50mm, the diameter of the piston rod III-2 is φ18mm, the theoretical maximum stroke is 40mm, and the theoretical net volume of the cylinder is 78ml. The working mode of the boost cylinder III is that the piston III-1 and the piston rod III-2 retract under the push of 0.2Mpa clean air, and are reset with the help of the compression spring III-4 on the piston rod III-2. In the three stages of ⑤ exhaust gas emission in the gas sampling cycle kT and ① precise calibration, ② balance and ③ headspace sampling in the next cycle (k+1)T, under the tension of the compression spring III-4, the piston rod III-2 extends, the piston III-1 returns to the initial position, the maximum net volume of the cylinder reaches 78ml, and 78ml of the malodorous gas to be measured is stored. In the ④ pressure doubling stage, due to the thrust of 0.2Mpa clean air, the piston III-1 and the piston rod III-2 move the maximum stroke of 40mm, the compression spring III-4 is compressed, the static volume of the cylinder gradually changes from 78ml to 0, and the 78ml of malodorous gas to be measured stored in the cylinder body III-3 is pressed back to the annular working chamber I-2 of the gas sensor array. The electronic nose instrument increases the adsorption of trace components by the sensitive membrane through the booster cylinder III to double the pressure in the annular working chamber I-2 of the gas sensor array, which is equivalent to increasing the concentration of trace components in the malodorous gas, and realizing the doubling of the sensitivity of gas sensing.

[0031] The boost cylinder III is placed at the rear end of the gas outlet of the annular working chamber I-2 of the gas sensor array. All gases flowing through the annular working chamber I-2 of the gas sensor array flow through the boost cylinder III and are finally discharged into the atmosphere as exhaust gas. The boost cylinder III is provided with two air inlets and one air outlet: the air inlet 1 is connected to the air outlet of the annular working chamber I-2 of the gas sensor array, the air inlet 2 is connected to the air outlet of the clean air bottle VI by means of a two-position two-way solenoid valve II-8, and the air outlet of the boost cylinder III is connected to the flow control and exhaust gas exhaust gas path by means of a two-position two-way solenoid valve II-5. The micro vacuum pump II-1 sucks the malodorous gas molecules remaining on the inner wall of the annular working chamber I-2 of the gas sensor array, the boost cylinder III and the related air pipelines at a flow rate of 6,000 ml / min for a long time, and the gas sensor array I-1 is thus initially restored to the reference state. Under the continuous purge of 1,000 ml / min clean air for 60 seconds, the gas sensor array I-1 accurately recovered to the reference state.

[0032] The electronic nose instrument is flexibly used in odor pollution observation points (i) in the field without AC power and (ii) in the field with AC power, and can flexibly perform (A) short-term limited real-time detection and analysis tasks on site and (B) long-term continuous online detection and analysis tasks lasting for hours, 1 day, several days or even months. Working scenario (i) + task (A): The instrument uses a backup power supply - 25.2V lithium battery pack V, with a nominal capacity of 10Ah, a battery pack weight of 2.5kg, a continuous working time of >3h, and can be recharged. At the same time, the instrument also uses a 2-6L aluminum alloy seamless clean air bottle VI-2, with a maximum working pressure of 15MPa, a size of φ111*359mm-φ140*629mm, and an air bottle weight of 2.8-7.2kg (the valve 0.8Kg is not included). Calculated based on the precise calibration time of clean air of 60s, the continuous working time is >2.5h. Working scenario (ii) + task (A): The instrument uses AC power and only uses 2-6L aluminum alloy seamless clean air bottle VI-2 to carry out short-term detection and analysis of odor pollution for 0.5-6h. Working scenario (ii) + task (B): The instrument uses AC power and uses a 40L large clean air bottle VI-1, with a maximum working pressure of 15MPa, a size of φ219*1450mm, and a weight of 45kg. It is still calculated based on the precise calibration time of clean air of 60s. One bottle of clean air can work continuously for about 20 days. Timely replacement of the exhausted large clean air bottle VI-1 can enable continuous online detection and analysis for a longer period of time.

[0033] Based on the existing manufacturing process level and existing finished products of gas sensors, measures to significantly improve the sensitivity and selectivity of gas sensors from the perspective of instrument structure design and industrial application include: (i) the design of the annular working chamber I-2 of the gas sensor array with two small cross-sectional sizes of 14×10mm and 16×20mm and a medium diameter of φ140mm and a small volume of 75ml, the booster cylinder III with a large headspace injection flow of 1,000ml / min and a net volume of 78ml to double the pressure in the annular working chamber I-2 of the gas sensor array in a short time, and the optimized combination of the three doubles the gas sensitivity. (ii) The three sensing components of steady-state peak value, peak time and area under the curve are simultaneously selected from the voltage response curve of a single gas sensor to significantly improve the gas sensitivity selectivity.

[0034] From the beginning of the 6th second of the ② equilibrium phase of the kth gas injection cycle, including the entire ③ headspace injection and ④ pressure doubling phases, until the end of the 5th second of the ⑤ exhaust gas emission phase, the computer control and analysis module IV records and stores the perception information of the gas sensor array I-1, which lasts for 70 seconds. From the beginning of the 6th second of the ⑤ exhaust gas emission phase of the cycle until the end of the 35th second, the electronic nose instrument enters the information processing and analysis phase, which lasts for 30 seconds. The computer control and analysis module IV selects multiple initial perception information components from each gas sensor voltage response curve of 70 seconds, and adds the on-site environmental temperature and humidity Tem,0 (k) and H um,0 (k) components constitute the initial sample x0(k). Based on this, the machine learning model determines the type of odor pollution and quantitatively estimates and predicts the values ​​of 8+1 concentration control indicators.

[0035] In the headspace sampling stage ③, the first two-position two-way solenoid valve II-4 and the second two-position two-way solenoid valve II-5 are turned on, the third two-position two-way solenoid valve II-6, the fourth two-position two-way solenoid valve II-7 and the fifth two-position two-way solenoid valve II-8 are turned off, and the piston rod III-2 of the booster cylinder III extends under the elastic force of the compression spring III-4, so that the cylinder body III-3 generates 78ml of storage space. Under the suction action of the micro vacuum pump II-1, the malodorous gas flows through the first two-position two-way solenoid valve II-4, the annular working chamber I-2 of the gas sensor array and the gas sensor array I-1, the cylinder body III-3, the second two-position two-way solenoid valve II-5, the throttle valve II-3, the flowmeter II-2 at a flow rate of 1,000ml / min, and is finally discharged into the atmosphere for 30s. The cylinder body III-3 stores 78ml of the malodorous gas to be measured. During the flow of the malodorous gas, the gas sensor array I-1 produces a sensitive response.

[0036] In the ④ pressure doubling stage, the fifth two-position two-way solenoid valve II-8 is turned on, the first two-position two-way solenoid valve II-4, the second two-position two-way solenoid valve II-5, the third two-position two-way solenoid valve II-6 and the fourth two-position two-way solenoid valve II-7 are turned off, and under the thrust of 0.2MPa clean air, the piston rod III-2 of the booster cylinder III is retracted, and the 78ml malodorous gas stored in the cylinder body III-3 is pressed back to the annular working chamber I-2 of the gas sensor array, which lasts for 30s. According to the ideal gas state equation p1V1=p2V2 under constant temperature conditions, the pressure of the annular working chamber I-2 of the gas sensor array gradually increases to 1 times. According to the Langmuir isothermal low-pressure adsorption equation, during this 30s period, the response size of the gas sensor array I-1 increases by about 1 times based on the headspace injection stage ③.

[0037] In the ⑤ exhaust gas discharge stage, the second two-position two-way solenoid valve II-5 and the fourth two-position two-way solenoid valve II-7 are turned on, the first two-position two-way solenoid valve II-4, the third two-position two-way solenoid valve II-6 and the fifth two-position two-way solenoid valve II-8 are turned off, the piston rod III-2 is extended again due to the elastic force of the compression spring III-4, and the cylinder body III-3 generates 78ml of space again. Under the suction action of the micro vacuum pump II-1, the residual exhaust gas in the annular working chamber I-2 of the gas sensor array and the cylinder body III-3 is extracted at a theoretical flow rate of 6,000ml / min, and the gas sensor array I-1 gradually recovers to the reference state. Subsequently, in the precise calibration stage ① of the next cycle, the second two-position two-way solenoid valve II-5 and the third two-position two-way solenoid valve II-6 are turned on, the first two-position two-way solenoid valve II-4, the fourth two-position two-way solenoid valve II-7 and the fifth two-position two-way solenoid valve II-8 are turned off, and the gas sensor array I-1 is accurately restored to the reference state under the action of 1,000 ml / min clean air purge lasting 60 seconds, and the malodor molecules remaining on the inner walls of the cylinder body III-3 and related pipelines are completely removed.

[0038] The online real-time detection and analysis of multiple components of odor by the Dinghuo Liangbian electronic nose instrument includes the following steps:

[0039] (1) Preparation: (i) For on-site real-time work scenarios with AC power supply, carry the main chassis and 2-6L small clean air bottle VI-2. (ii) For scenarios with AC power supply and continuous online work, fix the main chassis and 40L large clean air bottle VI-1. (iii) For field work scenarios without AC power supply, carry the main chassis, backup power supply - 25.2V lithium battery pack V and 2L small clean air bottle VI-2.

[0040] (2) Power on: Preheat the instrument for 30 minutes; set the “gas injection cycle T”, the default value is T = 5 minutes.

[0041] The second two-position two-way solenoid valve II-5 and the fourth two-position two-way solenoid valve II-7 are turned on, the first two-position two-way solenoid valve II-4, the third two-position two-way solenoid valve II-6 and the fifth two-position two-way solenoid valve II-8 are turned off, the piston rod III-2 is extended due to the elastic force of the compression spring III-4, and the cylinder body III-3 generates a 78ml space. Under the suction action of the micro vacuum pump II-1, the residual exhaust gas in the annular working chamber I-2 of the gas sensor array and the cylinder body III-3 is extracted at a flow rate of 6,000ml / min, and the gas sensor array I-1 gradually recovers to the reference state.

[0042] (3) The online real-time detection and analysis cycle of odorous gases begins:

[0043] (3.1) Malodorous gas detection:

[0044] In a gas sampling cycle T, depending on the gas type and flow rate, the gas sensor array module I undergoes the following steps: ① precise calibration,

[0045] There are five stages: ② balance, ③ headspace injection, ④ pressure doubling, and ⑤ exhaust gas emission. Table 1 shows the gas type, injection time length, start time, flow rate, and the on / off status of the five two-position two-way solenoid valves in each stage when T=300s.

[0046] From the beginning of the 6th second of the ⑤ exhaust gas emission phase to the end of the 35th second, the electronic nose instrument enters the information processing and analysis phase, which lasts for 30 seconds. From the beginning of the 6th second of the ② equilibrium phase, including the entire ③ headspace injection and ④ pressure doubling phases, to the end of the 5th second of the ⑤ exhaust gas emission phase, the computer control and analysis module IV records and stores the perception information of the gas sensor array I-1, which lasts for 70 seconds, and then

[0047] Table 1, gas sensor array module I operating parameters and related solenoid valve on / off status at gas sampling cycle T = 300s (default)

[0048]

[0049] Each gas sensor voltage response curve with a duration of 70 seconds selects multiple sensing information components, and the information component of the gas sensor array I-1 plus the local ambient temperature T em,0 (k) and ambient humidity H um,0 (k) together form the initial sample x0(k).

[0050] (3.2) Malodorous gas analysis:

[0051] Within 30 seconds after the end of data recording, the machine learning model determines the type of odor pollution based on the current perception sample x0(k) and the odor big data X, and quantifies and predicts the concentration control index values ​​of 8+1 odor pollutants online in real time.

[0052] (4) Once the gas sampling cycle kT-⑤ exhaust gas emission stage at the same odor pollution point is completed, either enter the next cycle (k+1)T and repeat the process (3), or move to the next odor pollution point to start new detection and analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 The present invention is a fixed-life electronic nose instrument and a method for online real-time detection of multiple components of malodor. The working principle of the multifunctional malodor electronic nose instrument is

[0054] Schematic diagram 1: The headspace injection position of malodorous gases, with continuous online working state with alternating current.

[0055] Figure 2 The present invention is a fixed-life electronic nose instrument and a method for online real-time detection of multiple components of malodor. The working principle of the multifunctional malodor electronic nose instrument is

[0056] Diagram 2: Pressure multiplication position, real-time working status in the field without AC power supply.

[0057] Figure 3 The present invention is a fixed-action electronic nose instrument and a method for online real-time detection of multiple components of malodors, an array arrangement of gas sensors and a gas sensor array.

[0058] Schematic diagram of the structure of the annular working chamber of the sensor array.

[0059] Figure 4 The present invention is a fixed-action electronic nose instrument and a method for online real-time detection of multiple components of malodors. The pressure multiplier device is a pressurized cylinder structure.

[0060] Schematic diagram; (a), the booster cylinder piston rod is in the retracted position, and the annular working chamber of the gas sensor is in the pressurized state; (b), the booster cylinder piston rod is in the extended position, and the annular working chamber of the gas sensor is in the initial recovery, precise calibration and head space injection state.

[0061] Figure 5 The present invention is a kind of electronic nose instrument for determining the odor of two stools and a method for online real-time detection of multiple components of odor.

[0062] Appearance (data analysis status) and back view.

[0063] Figure 6 The present invention is a kind of electronic nose instrument for determining the odor of two stools and a method for online real-time detection of multiple components of odor.

[0064] Scenarios; (a) long-term online detection scenario with AC power; (b) short-term real-time on-site detection scenario without AC power.

[0065] Figure 7 The present invention is a fixed-life electronic nose instrument and a method for online real-time detection of multiple components of malodor. Within a period of T = 360s, the gas sensor array

[0066] Schematic diagram of the changes in gas injection parameters and gas sensor response in the working chamber I-2. DETAILED DESCRIPTION

[0067] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0068] Figure 1This is one of the working principle diagrams of the multifunctional fixed-action and dual-use malodor electronic nose instrument of the present invention. The instrument is in the malodor gas headspace sampling position and is in a continuous online working state with alternating current. The main hardware components of the electronic nose instrument include: gas sensor array module I, gas automatic headspace sampling module II, booster cylinder III, computer control and analysis module IV, backup power supply-25.2V lithium battery pack V, 40L large clean air bottle VI-1, 2-6L small clean air bottle VI-2. Among them, the gas sensor array module I, gas automatic headspace sampling module II, booster cylinder III, computer control and analysis module IV, these four components constitute the main box.

[0069] Figure 2 This is the second schematic diagram of the working principle of the multifunctional fixed-action and dual-use malodor electronic nose instrument of the present invention. The instrument is in a malodor gas pressure multiplication position and is in a field real-time working state without an AC power supply. The main components of the gas sensor array module I include: gas sensor array I-1, gas sensor array annular working chamber I-2, thermal insulation layer I-3, partition I-4, fan I-5, resistance heating wire I-6, temperature sensor I-7, and are located in the upper right part of the main box of the electronic nose instrument.

[0070] The gas automatic headspace sampling gas circuit module II includes: a micro vacuum pump II-1, a flow meter II-2, a throttle valve II-3, a first two-position two-way solenoid valve II-4, a second two-position two-way solenoid valve II-5, a third two-position two-way solenoid valve II-6, a fourth two-position two-way solenoid valve II-7, a fifth two-position two-way solenoid valve II-8, and a purifier II-9. The booster cylinder III includes: a piston III-1, a piston rod III-2, a cylinder body III-3, a compression spring III-4, an O-ring III-5, an inner retaining ring III-6, a front cover III-7, and an anti-collision pad III-8. The gas automatic headspace sampling gas circuit module II and the booster cylinder III are located at the lower right in the main box of the electronic nose instrument.

[0071] The main components of the computer control and analysis module IV include: A / D data acquisition card IV-1, drive and control circuit board IV-2, computer mainboard IV-3, 4-way precision DC regulated power supply IV-4, WIFI board IV-5, touch screen IV-6, which are located on the left side of the main box of the electronic nose instrument.

[0072] Clean air bottles VI include: 40L large clean air bottle VI-1 and 2-6L small clean air bottle VI-2. Among them, the 40L large clean air bottle VI-1 is mainly used for long-term continuous online detection of odor for more than 2 hours; the 2-6L small clean air bottle VI-2 is used for short-term limited real-time detection of odor on site within 0.5-6 hours.

[0073] Figure 3(a) shows that the 16 gas sensors of the gas sensor array I-1 are arranged in a ring. Figure 3 (b)-(e) show that the middle diameter of the annular working chamber I-2 of the gas sensor array is φ140mm, the two annular sections are 16*20mm and 14*10mm respectively, and the net volume is about V0=75mm 3 The main components are the working chamber chassis I-2-1, the working chamber cover I-2-2, the sensor socket I-2-3, the hexagon socket screw I-2-4, the O-ring I-2-5, and the food-grade odorless sealant I-2-6.

[0074] Figure 4 This is a structural diagram of the booster cylinder III, a gas pressure multiplier device for the annular working chamber I-2 of the gas sensor array. The main components of the booster cylinder III are: piston rod III-1, piston III-2, cylinder body III-3, compression spring III-4, O-ring III-5, inner retaining ring III-6, front cover III-7, and anti-collision pad III-8. The booster cylinder III is a one-way introduction piston type ultra-thin type, with a piston III-1 diameter of φ50mm, a piston rod III-2 diameter of φ18mm, a maximum stroke of 40mm, and a theoretical net cylinder volume of 78ml; the piston III-1 and the piston rod III-2 extend under the push of 0.2Mpa clean air, and are reset with the help of the compression spring III-4 on the piston rod III-2. In the pressure doubling stage, due to the thrust of 0.2Mpa clean air, the piston III-1 and the piston rod III-2 move the maximum stroke of 40mm, the compression spring III-4 is compressed, and the static volume of the cylinder gradually changes from 78ml to 0, that is, 78ml of the malodorous gas to be measured is pressed back into the annular working chamber I-2 of the gas sensor array for a short time, so that the pressure in the annular working chamber I-2 is doubled in a short time, so as to increase the adsorption amount of the malodorous trace components by the gas sensitive membrane, which is equivalent to increasing the concentration of the trace components, and realizing the doubling of the sensitivity of the gas sensitive sensing. In the remaining 4 stages of a gas injection cycle T, with the help of the compression spring III-4, the piston III-1 returns to the initial position, and the maximum net volume of the cylinder is restored to 78ml. In particular, the booster cylinder III is provided with an air inlet 1 to allow the malodorous gas to be measured to enter the cylinder body III-3, so as to pressurize and accumulate gas inside the annular working chamber I-2 of the gas sensor array; and an air inlet 2 is provided so that the clean air can push the piston III-1 to move.

[0075] Figure 5(a) is the three-dimensional appearance of the main box of the fixed-use two-portable odor electronic nose instrument - data analysis status. The main box has an external dimension of 420 (width) × 380 (height) × 230 mm (depth). The gas sensor array module I is located in the upper right part, the gas automatic headspace sampling module II and the booster cylinder III are located in the lower right part, and the computer control and analysis module IV is located on the left. A 14” widescreen touch display (size: width w × height h × thickness t = 312 × 205 × 5 mm) is set on the front to display the perception curve of the gas sensor array I-1 for odor pollutants and the analysis results of the machine learning method in real time online. A flow meter is set to display the flow change in real time online. Here, the local ambient temperature and humidity are also measured and recorded. Figure 5 (b) is the layout diagram of the back of the instrument, which is generally equipped with mouse, keyboard, USB, monitor, Internet interface sockets, two air inlets for clean air and odorous gas, exhaust outlet, and two sockets for AC power and DC power.

[0076] Figure 6 (a) shows the long-term online detection working scenario of the fixed-duty two-way odor electronic nose instrument under AC power. The main box of the instrument plus the 40L large clean air bottle VI-1 can continuously detect and analyze odor pollutants online for several days or even dozens of days. The role of the operator is to replace the clean air bottle VI-1 that is about to run out with a new one in time. Figure 6 (b) A short-term on-site real-time detection working scenario of a fixed-action two-way odor electronic nose instrument in the field without AC power is given. The instrument main box is equipped with a 2-6L small clean air bottle VI-2 and a backup DC power supply - a 25.2V lithium battery pack V. It can detect a limited number of times at the odor pollution site and can work continuously for up to 6 hours; if necessary, a mobile AC power supply can be used instead of the backup DC power supply, and a 2-6L small clean air bottle can be carried. It should be pointed out that even in a working scenario with AC power, if the detection time is short-term, the fixed-action two-way odor electronic nose instrument of the present invention can use the instrument main box plus a small volume 2-6L small clean air bottle VI-2 to carry out short-term odor detection and analysis.

[0077] Figure 7 The diagram is a schematic diagram of the gas sampling type parameters of the gas sensor array working chamber I-2 and the sensing response changes of one of the gas sensors in a gas sampling cycle T=360s of the fixed-action and active-action electronic nose instrument of the present invention. Figure 7(a) A gas sampling cycle T = 300s includes five stages: ① Precise calibration: Under the action of 1,000ml / min clean air purge for 60s, the gas sensor array I-1 accurately recovers to the standard state; ② Balance: There is no gas flow in the annular working chamber I-2 of the gas sensor array, which lasts for 10s; ③ Headspace sampling: Under the suction action of the micro vacuum pump II-1 for 30s, the gas sensor array I-1 responds sensitively to the 1,000ml / min malodorous gas under test; ④ Pressure doubling: After 30s of pressure doubling, the gas sensor array I-1 responds sensitively to the 1,000ml / min malodorous gas under test; s of 0.2Mpa clean air thrust, the booster cylinder III presses the 78ml of stored malodorous gas back to the annular working chamber I-2 of the gas sensor array, increasing the pressure in the chamber by 1 times, and the response of the gas sensor array I-1 is further increased; ⑤ Exhaust gas emission: Under the suction action of the micro vacuum pump II-1 at a flow rate of 6,000ml / min for 170s, the exhaust gas from the annular working chamber I-2 of the gas sensor array, the booster cylinder III and related pipelines is extracted, and the gas sensor array I-1 gradually returns to its initial state.

[0078] It is particularly pointed out that an important capability that the electronic nose instrument used in industrial applications for online real-time detection and analysis of odor pollution should possess is that once a perception vector x(k) is obtained through on-site real-time detection, the instrument can estimate the 8+1 concentration control index values ​​of odor pollutants in real time on-site within 1 minute. As for the type of odor pollution, it is relatively secondary.

Claims

1. A fixed-life electronic nose instrument and a method for online real-time detection of multiple components of malodor, characterized in that: The electronic nose instrument hardware includes a gas sensor array module I, a gas automatic headspace sampling module II, a pressurized cylinder III, a computer control and analysis module IV, a backup power supply V, and a clean air bottle VI; among them, the gas sensor array module I, the gas automatic headspace sampling module II, the pressurized cylinder III, and the computer control and analysis module IV constitute the main chassis; the electronic nose instrument flexibly realizes fixed or mobile detection of odor pollution on site, identification of odor types, and quantitative estimation and prediction of the concentration of multiple odorous compounds; The gas sensor array module I comprises: a gas sensor array I-1, a gas sensor array annular working chamber I-2, a heat insulation layer I-3, a partition I-4, a fan I-5, a resistance heating wire I-6, and a temperature sensor I-7, which are located in the upper right part of the main box; the environmental temperature and humidity sensor I-8 is located in the upper right corner of the front inner wall of the main box body; The gas automatic head space sampling gas circuit module II comprises: a micro vacuum pump II-1, a flow meter II-2, a throttle valve II-3, a first two-position two-way solenoid valve II-4, a second two-position two-way solenoid valve II-5, a third two-position two-way solenoid valve II-6, a fourth two-position two-way solenoid valve II-7, a fifth two-position two-way solenoid valve II-8, and a purifier II-9; the booster cylinder III comprises: a piston III-1, a piston rod III-2, a cylinder body III-3, a compression spring III-4, an O-ring III-5, an inner retaining ring III-6, a front cover III-7, and an anti-collision pad III-8. The gas automatic head space sampling gas circuit module II and the booster cylinder III are located at the lower right in the main box; The computer control and analysis module IV mainly comprises: A / D data acquisition card IV-1, drive and control circuit board IV-2, computer mainboard IV-3, 4-way precision DC voltage-regulated power supply IV-4, WIFI board IV-5, touch screen IV-6, which are located on the left side in the main box; Clean air bottles VI include: 40L large clean air bottle VI-1 and 2-6L small clean air bottle VI-2; 40L large clean air bottle VI-1 is mainly used for long-term continuous online detection of odor on-site for more than 2 hours; 2-6L small clean air bottle VI-2 is used for limited short-term real-time detection of odor on-site within 0.5-6 hours; The Dinghuo two-hand electronic nose instrument forms a large odor data set X through long-term continuous online detection or short-term multiple detection of various odor pollution sites. The machine learning model learns from this data set to master the correspondence between the gas sensor array response and 8 single components and 1 overall odor concentration control indicators, including hydrogen sulfide H2S, ammonia NH3, methyl mercaptan CH4S, dimethyl disulfide C2H6S2, methyl sulfide C2H6S, carbon disulfide CS2, trimethylamine C3H9N, and styrene C8H8, namely 8+1 odor pollutant concentration control indicators, and determines the odor pollution type based on this in the decision-making stage, and estimates and predicts the 8+1 odor pollutant concentration control indicator values ​​online in real time.

2. The electronic nose instrument for fixed and live feces and the method for online real-time detection of multiple components of malodor according to claim 1 are characterized in that: The gas sensor array I-1 and its annular working chamber I-2 are located in a constant temperature room at 55±0.1℃. Within the default value of the gas sampling cycle T=300s, the gas sensor array I-1 and its annular working chamber I-2 go through the following five stages in turn, depending on the type and flow of the gas: ① Accurate calibration: Under the action of 1,000ml / min clean air purge, the gas sensor array I-1 gradually and accurately recovers to the standard state, which takes 60s; ②Balance: There is no gas flow in the annular working chamber I-2 of the gas sensor array, which lasts for 10 seconds; ③Headspace sampling: Under the suction of the micro vacuum pump II-1, the gas sensor array I-1 responds sensitively to the 1,000ml / min malodorous gas being measured, which lasts for 30 seconds; ④Pressure doubling: Under the thrust of 0.2Mpa clean air, the 78ml malodorous gas in the booster cylinder III is pressed back to the annular working chamber I-2 of the gas sensor array, and the pressure in the chamber increases by about 1 times in a short time, so the sensitive response of the gas sensor array I-1 is further increased, which lasts for 30 seconds; ⑤Exhaust emission: Under the micro vacuum pump Under the suction action of II-1, the exhaust gas from the annular working chamber I-2 of the gas sensor array, the boost cylinder III and the related gas pipelines is discharged into the atmosphere, which lasts for 170s; as the odorous exhaust gas is discharged, the gas sensor array I-1 gradually returns to its initial state; if the gas sampling cycle T>300s, the exhaust gas emission time is extended accordingly, and the flow rate and duration of the other four stages remain unchanged; for example, if T=480s, the exhaust gas emission time length is 170+(480-300)=350s; if T<300s, the exhaust gas emission time length is 170+(T-300)<170s.

3. The electronic nose instrument for fixed and live feces and the method for online real-time detection of multiple components of malodor according to claim 1 are characterized in that: According to the ideal gas state equation under constant temperature conditions p1V1=p2V2 and the classical Langmuir isothermal low-pressure adsorption equation q=γpq m / (1+γp), where p1, p2 and p are pressures, V1 and V2 are volumes, q is the adsorption amount, q m is the saturated adsorption amount, γ is the equilibrium constant, and the present invention uses the booster cylinder III to achieve the increase of the adsorption amount of trace components with the increase of pressure; the specific measures are: designing a small volume and small section gas sensor array annular working chamber I-2 with a middle diameter of φ140mm and two cross-sectional sizes of 14×10mm and 16×20mm and a net volume of 75ml; designing a one-way introduction ultra-thin piston booster cylinder III, The diameter of piston III-1, i.e. the cylinder diameter, is φ50mm, the diameter of piston rod III-2 is φ18mm, the theoretical maximum stroke is 40mm, and the theoretical net volume of the cylinder is 78ml; the working mode of booster cylinder III is that piston III-1 and piston rod III-2 are retracted under the push of 0.2Mpa clean air, and are reset with the help of compression spring III-4 on piston rod III-2; in the ⑤ exhaust gas emission stage of the gas injection cycle kT and the three stages of ① precise calibration, ② balance and ③ head space injection of the next cycle (k+1)T, under the tension of compression spring III-4, piston rod III-2 is extended, piston III-1 returns to its initial position, and the maximum net volume of the cylinder is Reaching 78ml, storing 78ml of the malodorous gas to be measured; in the ④ pressure doubling stage, due to the thrust of 0.2Mpa clean air, the piston III-1 and the piston rod III-2 move the maximum stroke of 40mm, the compression spring III-4 is compressed, and the static volume of the cylinder gradually changes from 78ml to 0, and the 78ml of the malodorous gas to be measured stored in the cylinder body III-3 is pressed back into the annular working chamber I-2 of the gas sensor array; the electronic nose instrument uses the booster cylinder III to short-term double the pressure in the annular working chamber I-2 of the gas sensor array to increase the adsorption amount of trace components by the sensitive membrane, which is equivalent to increasing the concentration of trace components in the malodorous gas, thereby doubling the sensitivity of the gas sensor.

4. The electronic nose instrument for fixed and live feces and the method for online real-time detection of multiple components of malodor according to claim 1 are characterized in that: The boost cylinder III is placed at the rear end of the air outlet of the annular working chamber I-2 of the gas sensor array. All gases flowing through the annular working chamber I-2 of the gas sensor array flow through the boost cylinder III and are finally discharged into the atmosphere as exhaust gas. The boost cylinder III is provided with two air inlets and one air outlet: the air inlet 1 is connected to the air outlet of the annular working chamber I-2 of the gas sensor array, the air inlet 2 is connected to the air outlet of the clean air bottle VI by means of a two-position two-way solenoid valve II-8, and the air outlet of the boost cylinder III is connected to the air outlet of the clean air bottle VI by means of a two-position two-way solenoid valve II-8. The two-position two-way solenoid valve II-5 is connected to the flow control and exhaust gas exhaust path; the micro vacuum pump II-1 sucks the odorous gas molecules remaining in the annular working chamber I-2 of the gas sensor array, the boost cylinder III and the inner wall of the related gas pipeline at a flow rate of 6,000ml / min for a long time, so that the gas sensor array I-1 is initially restored to the reference state; under the continuous purge of 1,000ml / min of clean air for 60s, the gas sensor array I-1 is accurately restored to the reference state.

5. The electronic nose instrument for fixed and live feces and the method for online real-time detection of multiple components of malodor according to claim 1 are characterized in that: The electronic nose instrument is flexibly used in odor pollution observation points (i) in the field without AC power and (ii) in the field with AC power, and can flexibly perform (A) on-site short-term limited real-time detection and analysis tasks and (B) long-term continuous online detection and analysis tasks lasting for hours, 1 day, several days or even months; working scenario (i) + task (A): the instrument uses a backup power supply - 25.2V lithium battery pack V, with a nominal capacity of 10Ah, a battery pack weight of 2.5kg, a continuous working time of >3h, and can be recharged; at the same time, the instrument also uses a 2-6L aluminum alloy seamless clean air bottle VI-2, with a maximum working pressure of 15MPa, a size of φ111*359mm-φ140*629mm, and an air bottle weight of 2.8-7.2kg (valve 0. 8Kg is not included), calculated based on the precise calibration time of clean air of 60s, the continuous working time is >2.5h; Working scenario (ii) + task (A): the instrument uses AC power and only adopts 2-6L aluminum alloy seamless clean air bottle VI-2 to carry out short-term detection and analysis of odor pollution for about 0.5-6h; Working scenario (ii) + task (B): the instrument uses AC power and adopts 40L large clean air bottle VI-1 at the same time, with the maximum working pressure of 15MPa, size φ219*1450mm, and the air bottle weighs 45kg. It is still calculated based on the precise calibration time of clean air of 60s. One bottle of clean air can work continuously for about 20 days. Timely replacement of the exhausted clean air bottle VI-1 can enable continuous online detection and analysis for a longer time.

6. The electronic nose instrument for fixed and active defecation and the method for online real-time detection of multiple components of malodor according to claim 1 are characterized in that: Based on the existing manufacturing process level and existing finished products of gas sensors, measures to significantly improve the sensitivity and selectivity of gas sensors from the perspective of instrument structure design and industrial application include: (i) the structural design of the annular working chamber I-2 of the gas sensor array with two small cross-sectional sizes of 14×10mm and 16×20mm, a middle diameter of φ140mm and a small volume of 75ml, a booster cylinder III with a large headspace injection flow of 1,000ml / min and a net volume of 78ml to double the pressure in the annular working chamber I-2 of the gas sensor array in a short time, and the optimized combination of the three doubles the gas sensitivity; (ii) the three sensing components of steady-state peak value, peak time and area under the curve are simultaneously selected from the voltage response curve of a single gas sensor to significantly improve the gas sensitivity selectivity.

7. The electronic nose instrument for fixed and live feces and the method for online real-time detection of multiple components of malodor according to claim 1 are characterized in that: From the beginning of the 6th second of the ② equilibrium stage of the k-th gas injection cycle, including the entire ③ headspace injection and ④ pressure doubling stages, until the end of the 5th second of the ⑤ exhaust gas emission stage, the computer control and analysis module IV records and stores the perception information of the gas sensor array I-1, which lasts for 70 seconds; from the beginning of the 6th second of the ⑤ exhaust gas emission stage of the cycle to the end of the 35th second, the electronic nose instrument enters the information processing and analysis stage lasting 30 seconds, and the computer control and analysis module IV selects multiple initial perception information components from each gas sensor voltage response curve of 70 seconds, and adds the on-site environmental temperature and humidity T em,0 (k) and H um,0 (k) components constitute the initial sample x0(k); the machine learning model determines the type of odor pollution based on this, and quantitatively estimates and predicts the values ​​of 8+1 concentration control indicators.

8. The electronic nose instrument for fixed and active defecation and the method for online real-time detection of multiple components of malodor according to claim 1, characterized in that ③ In the headspace sampling stage, the first two-position two-way solenoid valve II-4 and the second two-position two-way solenoid valve II-5 are turned on, the third two-position two-way solenoid valve II-6, the fourth two-position two-way solenoid valve II-7 and the fifth two-position two-way solenoid valve II-8 are turned off, and the piston rod III-2 of the booster cylinder III extends out under the elastic force of the compression spring III-4, so that the cylinder body III-3 generates 78 ml of storage space; under the suction action of the micro vacuum pump II-1, the malodorous gas flows through the first two-position two-way solenoid valve II-4, the gas sensor array annular working chamber I-2 and the gas sensor array I-1, the cylinder body III-3, the second two-position two-way solenoid valve II-5, the throttle valve II-3, the flowmeter II-2 at a flow rate of 1,000 ml / min, and is finally discharged into the atmosphere, which takes 30 seconds; during the flow of the malodorous gas, the gas sensor array I-1 produces a sensitive response.

9. The electronic nose instrument for fixed and active defecation and the method for online real-time detection of multiple components of malodor according to claim 1, characterized in that ④In the pressure doubling stage, the fifth two-position two-way solenoid valve II-8 is turned on, the first two-position two-way solenoid valve II-4, the second two-position two-way solenoid valve II-5, the third two-position two-way solenoid valve II-6 and the fourth two-position two-way solenoid valve II-7 are turned off, and under the thrust of 0.2MPa clean air, the piston rod III-2 of the booster cylinder III is retracted, and the 78ml of malodorous gas stored in the cylinder body III-3 is pressed back into the annular working chamber I-2 of the gas sensor array, which takes 30s; according to the ideal gas state equation p1V1=p2V2 under constant temperature conditions, the pressure in the annular working chamber I-2 of the gas sensor array gradually increases by 1 times, and according to the Langmuir isothermal low-pressure adsorption equation, the response size of the gas sensor array I-1 increases by about 1 times based on the headspace injection stage ③.

10. The electronic nose instrument for fixed and active defecation and the method for online real-time detection of multiple components of malodor according to claim 1, characterized in that: In the exhaust gas discharge stage ⑤, the second two-position two-way solenoid valve II-5 and the fourth two-position two-way solenoid valve II-7 are turned on, and the first two-position two-way solenoid valve II-4, the third two The first two-position two-way solenoid valve II-6 and the fifth two-position two-way solenoid valve II-8 are disconnected, the piston rod III-2 is extended again due to the elastic force of the compression spring III-4, and the cylinder body III-3 generates 78ml of space again; under the suction action of the micro vacuum pump II-1, the residual exhaust gas in the annular working chamber I-2 of the gas sensor array and the cylinder body III-3 is extracted at a theoretical flow rate of 6,000ml / min, and the gas sensor array I-1 gradually recovers to the reference state; then, in the next cycle of the precise calibration stage ①, the second two-position two-way solenoid valve II-5 and the third two-position two-way solenoid valve II-6 are connected, the first two-position two-way solenoid valve II-4, the fourth two-position two-way solenoid valve II-7 and the fifth two-position two-way solenoid valve II-8 are disconnected, and the gas sensor array I-1 is accurately restored to the reference state under the action of the 1,000ml / min clean air purge lasting 60s, and the malodor molecules remaining on the inner wall of the cylinder body III-3 and the related pipelines are completely removed.

11. The electronic nose instrument for fixed and active defecation and the method for online real-time detection of multiple components of malodor according to claims 1-10, characterized in that: The online real-time detection and analysis of multiple components of odor by the Dinghuo Liangbian electronic nose instrument includes the following steps: (1) Preparation: (i) For on-site real-time work scenarios with AC power supply, carry the mainframe and 2-6L small clean air bottle VI-2; (ii) For scenarios with AC power supply and continuous online work, fix the mainframe and 40L large clean air bottle VI-1; (iii) For field work scenarios without AC power supply, carry the mainframe, backup power supply - 25.2V lithium battery pack V and 2-6L small clean air bottle VI-2; (2) Power on: Preheat the instrument for 30 minutes; set the "gas injection cycle T", the default value T = 5 minutes; The second two-position two-way solenoid valve II-5 and the fourth two-position two-way solenoid valve II-7 are turned on, the first two-position two-way solenoid valve II-4, the third two-position two-way solenoid valve II-6 and the fifth two-position two-way solenoid valve II-8 are turned off, the piston rod III-2 is extended due to the elastic force of the compression spring III-4, and the cylinder body III-3 generates a 78ml space; under the suction action of the micro vacuum pump II-1, the residual exhaust gas in the annular working chamber I-2 of the gas sensor array and the cylinder body III-3 is extracted at a flow rate of 6,000ml / min, and the gas sensor array I-1 gradually and preliminarily recovers to the reference state; (3) The online real-time detection and analysis cycle of odorous gases begins: (3.1) Malodorous gas detection: In a gas sampling cycle T, depending on the gas type and flow rate, the gas sensor array module I goes through five stages in sequence: ① precise calibration, ② balance, ③ headspace sampling, ④ pressure doubling, and ⑤ exhaust gas emission; Table 1 shows the gas parameters of each stage when T = 300s. Table 1 shows the working parameters of the gas sensor array module I and the on / off status of the related solenoid valves in the gas sampling cycle T = 300s (default). Liquid type, injection time, start time, flow rate and the on / off status of 5 two-position two-way solenoid valves; From the beginning of the 6th second of the ⑤ exhaust gas emission phase to the end of the 35th second of the cycle T, the electronic nose instrument enters the information processing and analysis phase lasting 30 seconds; from the beginning of the 6th second of the ② equilibrium phase, including the entire ③ headspace injection and ④ pressure doubling phases, until the end of the 5th second of the ⑤ exhaust gas emission phase, the computer control and analysis module IV records and stores the perception information of the gas sensor array I-1 for 70 seconds, and then selects multiple perception information components from each gas sensor voltage response curve with a duration of 70 seconds, and the information components of the gas sensor array I-1 are added to the local ambient temperature T at that time. em,0 (k) and ambient humidity H um,0 (k) together form the initial sample x0(k); (3.2) Malodorous gas analysis: Within 30 seconds after the data recording ends, the machine learning model determines the type of odor pollution based on the current perception sample x0(k) and the odor big data X, and quantifies and estimates the concentration control index values ​​of 8+1 odor pollutants online in real time; (4) Once the gas sampling cycle kT-⑤ exhaust gas emission stage at the same odor pollution point is completed, either enter the next cycle (k+1)T and repeat the process (3), or move to the next odor pollution point to start new detection and analysis.

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