DOAS double sampling technology based coal seam gas combined measurement system

The invention discloses a DOAS double sampling technology based coal seam gas combined measurement system. The DOAS double sampling technology based coal seam gas combined measurement system comprises a tiny-amount gas double sampling system and a DOAS double sampling system. The tiny-amount gas double sampling system comprises two sample gas chambers, a gas pump and a pressure gauge; and continuous online acquisition of a gas in a gas drainage pipeline is carried out by the double sampling system, and the acquired sample gas is collected in the two sample gas chambers. Each of the two sample gas chambers is an elliptic cylinder air chamber; and the use of the pressure gauge and the gas pump realizes the normal acquisition of the sample gas whenever the pressure in the gas drainage pipeline is positive or negative. The DOAS double sampling detection system comprises a light source generator, a splitter, a receiver, a spectrometer and CCD optoelectronic coupler, a data collection card and an industrial control