Automatic monitoring technology of ambient air quality

Applicating Company

Tianjin Shareshine Technology Development Co., Ltd

Technology Name

Automatic monitoring technology of ambient air quality

Technical principle

1.Particulate matter monitor

Instrument use β Ray attenuation principle to monitor particulate matter: when the air sample with known volume is introduced into the sampling head with optional particle size (PM-10, PM-2.5, PM-1 and TSP sampling heads can be configured), and is continuously collected on the automatically movable filter belt, when β When the ray passes through the filter membrane deposited with particles, β The energy attenuation of X-rays can be measured to calculate the concentration of particles. The instrument has successfully applied particulate matter β Based on the real-time measurement technology of ray attenuation β The compensation of ray background interference can provide more accurate particle quality data.

2. Gaseous pollutants

(1) SO2

The instrument uses the principle of ultraviolet fluorescence method to monitor sulfur dioxide. Ultraviolet fluorescence method is a spectral method based on molecular emission. When ultraviolet light irradiates SO2 gas molecules, it will become excited state. After the excited state, because the system will seek the lowest energy stable state, the molecule will soon return to its ground state. When the excited state molecule returns to the ground state, it will emit another ultraviolet light of different wavelength. The emitted ultraviolet light is proportional to the SO2 concentration, and the SO2 concentration can be obtained by measuring the ultraviolet light intensity.

(2) No2

The instrument uses the chemiluminescence principle to monitor nitrogen oxides: the reaction between NO and O3 will produce a unique light, and the light intensity is linear with the concentration of No. No2 needs to be converted into no by converter, and then measured by chemiluminescence reaction.

The air sample enters the analyzer through the sampling system and then flows to the mode solenoid valve. The solenoid valve sends the sample directly to the reaction chamber (no mode) or sends it to the reaction chamber through the converter (NOx mode). Dry air also enters the analyzer through the sampling system and generates O3 through the ozone generator.

In the reaction chamber, O3 reacts with no to produce stimulated NO2 molecules, and then photomultiplier tube (PMT) is used to detect the light generated in the reaction. Calculate the concentration and concentration difference of no and NOx respectively to obtain the concentration of NO2.

(3) O3

The instrument adopts ultraviolet absorption method and can measure the ozone content of ppb level. The concentration of ozone is determined by the difference between the UV signal absorbed by the sample gas and the UV signal absorbed by the sample gas after ozone removal. In the measurement module with temperature control adjustment, a sealed ozone eliminator is installed, which is easy to replace and disassemble and has a powerful and easy-to-use interface module. During span calibration of the instrument, it can be displayed through real-time chart.

(4) Co

The instrument uses the gas filter correlation infrared absorption method to detect the CO concentration. Through the 4.67 μ m infrared absorption characteristics of carbon monoxide, the photoelectric detector is used to detect the intensity of the absorbed light, and the concentration of carbon monoxide is calculated by using the beer Lambert law. The instrument measurement module and relevant runner are installed in the sealed foam box to ensure constant temperature and eliminate the interference of external environment, with higher accuracy and reliability, and extremely low maintenance.

Scope of application

According to the national standards, combined with the monitoring capacity building requirements of the new air quality standards, and in accordance with the technical specifications for the layout of ambient air quality monitoring points, the system monitors the ambient air quality of environmental air quality monitoring points with different functions, such as pollution source monitoring points, air quality evaluation points, air quality control points and air quality background points. The system integrates data collection, data review, statistical analysis, report release, map display and other functions, and can release monitoring data and AQI in real time. The system is applicable to ambient air quality monitoring, road traffic, industrial parks, rural stations, venues monitoring, environmental assessment monitoring, etc.

Process flow and description

1 Incoming inspection

The quantity and quality inspection shall be carried out for the purchased equipment components and auxiliary materials to ensure that they meet the requirements, and whether the incoming materials are allowed to be put into storage shall be judged.

2 Auxiliary material assembly

According to the equipment drawings, installation instructions and other process documents, complete the assembly of equipment accessories according to the process.

3 Assembly of components

According to the equipment drawings, installation instructions and other process documents, complete the assembly of equipment components according to the process.

4 Process commissioning

After the complete machine is assembled, complete the commissioning of the system equipment according to the installation and commissioning instructions.

5 Final inspection

After installation and commissioning, full-time personnel shall conduct sampling quality inspection on the equipment to ensure that the product performance, accuracy, safety and appearance meet the quality requirements.

6 packing of products

Before packaging, check the product packaging list to ensure that there is no omission of required accessories and technical documents.

Promotion prospects

Our products are selected from the world's advanced automatic quality monitoring technology and the most advanced and reliable devices. Based on independent development, we adhere to the technical route of low-cost and high reliability, improve the stability and accuracy of the system, and make it easy to master, operate and maintain. The system is widely used for on-line real-time continuous monitoring of air quality in various environments and transmitting field data to environmental protection departments. The results and monitoring system of the project, with all independent intellectual property rights, have high social and economic benefits and broad prospects.