Portable dust monitoring instrument using beta rays

Portable dust monitoring instrument using beta raysThe instrument host is installed indoors and connected to an outdoor cutting head (PM10 or PM2.5) through a sealed pipeline. It can handle atmospheric particulate matter PM10 (aerodynamic diameter ≤ 10um) and PM2.5 (aerodynamic diameter ≤ 2.5um).

The instrument uses beta rays as a radiation source and an air pump to sample the atmosphere. During sampling, the monitor monitors the real-time flow rate of the extracted air. Suspended particles in the atmosphere are adsorbed on the surface of the filter paper between the beta source and the scintillation detector. The change in the scintillation detector count before and after extraction reflects the mass of dust adsorbed on the filter paper, which is converted into the concentration of suspended particles per unit volume of air based on the volume used.

It can automatically measure and record concentration, using the working principle of beta ray absorption method. C-14 is used as the emission source, which emits constant high-energy electrons. The sample air passes through the injection tube at a constant flow rate through the cutter, and the particles are trapped on the filter membrane. When beta rays pass through the filter membrane, energy is attenuated. The mass of particulate matter is calculated by measuring the attenuation amount, and the actual concentration of particulate matter in the ambient air is calculated based on the sampling flow rate, sampling time, and filter membrane area. This device is suitable for online monitoring of particulate matter in construction sites, road construction, factory boundaries, and other areas.

The beta ray dust online monitoring device consists of a sampling pump, a cutter, a beta source, a power supply, a detection system, a temperature and humidity control system (DHS), a data acquisition and processing unit, a data transmission unit, supporting software, and auxiliary units. Optional wind direction, wind speed, video surveillance, and LED display screen.

Portable dust monitoring instrument using beta raysThe key components of the beta ray dust monitoring equipment are particulate matter and climate monitoring modules. Data collection control component. Short video recognition symbol accumulation module. Transmission data module. Data display service platform. Connect operation modules, etc. The key comes from monitoring and analyzing particulate matter in the air, and transmitting monitoring data information to electronic computers.

The online monitoring instrument for β - ray particulate matter adopts the β - ray absorption method, using low-energy C14 as the β - ray source. The mass of particulate matter collected on the filter paper is calculated based on the change of β - ray passing through the clean filter paper and the filter paper with particulate matter collected, that is, the concentration of particulate matter in the air is obtained. Widely applicable for measuring the concentration of particulate matter in ambient air, such as pm10, pm2.5, TSP (with different sampling and cutting heads available), etc. The overall design of the instrument is reasonable, aesthetically pleasing, easy to use, and easy to maintain. The online monitoring equipment for PM10 using the β - ray method is generally divided into two types: step-by-step and continuous. Stepper instruments generally output 1 data per hour, while continuous instruments can perform continuous measurements.