Mention of VOC detection, may be more familiar with the environmental protection industry partners, today the network xiaobian mainly share with you the PID photoionized gas sensor detection method of VOC.
What is VOC?
VOC is the abbreviation of volatile organic compounds. It is a general term for all organic compounds discharged into the air at room temperature in the form of gaseous molecules. VOC covers a wide variety of organic compounds and its components are diverse, mainly: chloride, benzene compounds, freon compounds, organic alcohols, organic ketones, organic ethers, organic aldehydes, organic esters, organic amines, organic acids and petroleum hydrocarbon compounds. VOC and the secondary pollutants formed by it not only have strong toxicity to people’s health, but also affect the air quality as a precursor of ozone and PM2.5, and is one of the main “contributors” to compound air pollution.
Detection method of VOC
Common VOC detection methods include PID detection, GC-FID and GC-MS detection, in which GC-FID and GC-MS are used to detect the total value of VOC gas, in a mixed gas environment can not detect a single VOC gas. Gc-fid and GC-MS can also measure specific VOC gas composition, but they are expensive and bulky. PID sensor is small in size, low in price, simple in working conditions, low in energy consumption, more suitable for portable detector.
What is PID?
For instrument analysis partners, may be on GC-FID (hydrogen flame ionization detector) and GC-MS (GC) use more clearly, we focus today on PID (photoionization detector).
Photoionized gas sensor (PID) consists of ultraviolet light source and gas chamber. In PID, the ionization source of the gas to be measured is the UV lamp in the ionization chamber. After the measured gas reaches the gas chamber, the ultraviolet light emitted by the UV lamp will generate charge flow. The gas concentration is positively correlated with the size of the charge flow, and the gas concentration can be measured by measuring the charge flow. Ultraviolet luminescence principle is the same as sunlight lamp, but high frequency, high energy.
PID working principle:
The vacuum glass chamber is filled with high purity rare gas such as inert gas. The glass chamber is sealed with a window that can penetrate ultraviolet light. Excited by an applied electromagnetic field.
PID sensor type and brand research. PID sensor can be classified according to uv lamp energy, life and detection gas, mainly can be divided into the following types.
JXCT PID sensor
JXCT PID sensor realizes rapid detection of VOC gas, is waterproof, easy to clean, durable, multi-range selection, and accurate measurement. PID module is high sensitive and quick react. It can help you alarm the VOC at the first time and make sure your health. It can be widely used in VOC detection in factories, mining areas, chemical industry areas and other environments