Piezoelectric resonant type PM2.5 monitoring system

Abstract

The invention discloses a piezoelectric resonant type PM2.5 monitoring system. Based on a piezoelectric resonant frequency difference method and by adopting a modular design, the piezoelectric resonant type PM2.5 monitoring system mainly comprises a control unit, and an electrostatic precipitation sampling unit, a piezoelectric resonance unit, a frequency testing unit and a display unit which areconnected with the control unit, wherein the electrostatic precipitation sampling unit mainly comprises an impact type inertia classifier and an electrostatic precipitator; and the piezoelectric resonance unit mainly comprises a piezoelectric quartz crystal resonator, an amplifier and a low-voltage power supply. The piezoelectric quartz crystal resonator is a double-quartz crystal resonator consisting of two identical piezoelectric quartz crystal oscillating circuits, a relational model between the piezoelectric resonant frequency and piezoelectric crystal wafer quality is established, the mass concentration of PM2.5 is determined according to the change of the piezoelectric resonant frequency, one oscillating circuit of the double-quartz crystal resonator is a measurement end, and the other oscillating circuit is a reference end. The collection rate of PM2.5 particulate matters is stable, and the monitoring sensitivity is not influenced by multiple factors including ambient temperature and the like.

Description

technical field [0001] The invention relates to PM2.5 monitoring, in particular to a piezoelectric resonance PM2.5 monitoring system. Background technique [0002] PM2.5 refers to fine particles with a particle size below 2.5 μm, which has become the primary pollutant in the urban atmosphere at home and abroad. The piezoelectric crystal oscillator method, also known as the piezoelectric crystal oscillator frequency difference method, is a method for measuring the PM2.5 mass concentration based on the change of the resonance frequency of the piezoelectric element. It has the advantages of high monitoring sensitivity, good selectivity, and relatively simple equipment, and has become increasingly popular. People in the relevant industry pay attention to it, but its defect is that the collection rate of PM2.5 particulate matter is not stable enough, and its monitoring sensitivity is easily affected by many factors including ambient temperature. Contents of the invention [00...

AI Technical Summary

Problems solved by technology

The piezoelectric crystal oscillator method, also known as the piezoelectric crystal oscillator frequency difference method, is a method for measuring the PM2.5 mass concentration based on the change of the resonance frequency of the piezoelectric element. It has the advantages of high monitoring sensitivity, good selectivity, and relatively simple equipment, and has become increasingly popular. People in the relevant industry pay attention to it. The defect is that the collection rate of PM2.5 particulate matter is not stable enough, and its monitoring sensitivity is easily affected by many factors including ambient temperature.

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