Update: 2019-12-03 16:18 Source: LUFTMY
The diameter of the floating dust particles is less than 10 microns, which can float in the air for a long time, and can enter the respiratory tract of human body through breathing. The floating dust, also known as the inhalable particles, is the granular floating substance produced when the substance burns, which is very harmful to health. When the particle size is less than 2.5 microns, most of them can be deposited into the lungs through the respiratory tract, which is more harmful to the human body. Dust pollution is an important aspect of air pollution, and the control of dust pollution has gradually attracted people's attention.
Haze and dust
Due to its small size, long floating time and wide range, floating dust is accumulating in the atmosphere. When it is in contact with sulfur dioxide and oxygen in the air, sulfur dioxide will be partially converted into nitrogen trioxide, which increases the acidity of the air and makes the pollution level worsen gradually. In addition, the small diameter dust (PM2.5) in the air also promotes the reaction of oxygen and sulfur dioxide to form sulfur trioxide, which is one of the main sources of acid rain. Floating dust is also the carrier and catalyst of many pollutants. It can absorb a variety of harmful and toxic substances that people discharge into the atmosphere.
Generally speaking, the main source of small diameter floating dust (PM2.5) is industrial production, automobile exhaust emission and other residues in combustion process. The main source of PM2.5 is man-made emission. Some gaseous pollutants emitted by human body are converted into PM2.5 in the air. The direct emission mainly comes from the combustion process, such as the combustion of coal, gasoline, diesel, burning straw, firewood, burning garbage, etc.
PM2.5 sensor can be used for the detection of dust concentration. The PM2.5 sensor is equipped with infrared light-emitting diode and phototransistor. Their optical axes intersect. When the dust air flows through the intersection of optical axes, the floating dust will appear on the infrared light. The reflection intensity of the reflected light is directly proportional to the dust concentration.The infrared light-emitting diode emits light and encounters dust to generate reflected light, receives PM2.5 sensor to detect the intensity of reflected light, outputs signal, determines dust concentration according to the intensity of output signal, and outputs two different pulse width modulation signals (PWM) to distinguish the concentration of different dust particles. GDS06 infrared sensor can be used for the detection of dust concentration:
PM2.5 sensor gds06 detects about 0.3μm particles, such as indoor dust, pollen, microorganism, dust mite and cigarette smoke, and measures the concentration of floating particles in a space of no more than 10μM. The signal of PM2.5 sensor gds06 is converted into PWM output through internal circuit and program; the detection ability of PM2.5 sensor gds06 product is stable, the production efficiency is high, and it has double advantages.
HPD05 high quality PM2.5 sensor is a small module which uses the principle of optical scattering to detect the dust particles in the air. It has the advantages of small volume, high detection accuracy, good repeatability, good consistency, continuous real-time response, strong anti-interference ability, super quiet fan, 100% detection and calibration of the sensor.
The infrared PM2.5 sensor HPD05 uses the principle of optical scattering to obtain the particle concentration, and measures the dust concentration within the detection range through the conversion of optical path and circuit. High precision PM2.5 sensor HPD05 has the characteristics of small volume, high precision, low power consumption, short response time and stable operation under high dust concentration. This high precision PM2.5 sensor can be applied to air purifier and fresh air system.