Chromatographic sample introduction two-stage thermal desorption apparatus and method thereof

The invention discloses a chromatographic sample introduction two-stage thermal desorption apparatus. The apparatus is characterized in that a first stable flow valve is connected with a first solenoid valve, the first solenoid valve is connected with a first heating device, the first heating device is connected with a second heating device, the second heating device is connected with a third solenoid valve, the third solenoid valve is connected with a chromatography device, the third solenoid valve is also provided with a first emptying channel, a first Tenax tube is arranged in the second heating device, a gas channel m is connected with a second pressure stabilizing valve, the second pressure stabilizing valve is connected with a second solenoid valve, the second solenoid valve is connected with a fourth solenoid valve, the fourth solenoid valve is connected with a heating-refrigerating device, and the heating-refrigerating device is connected with a third solenoid valve; and the first heating device is provided with a sample introduction device, and a second Tenax tube is arranged in the heating-refrigerating device. The arrangement of a two-stage thermal desorption gas channel portion and the first heating device for making standardized serial tubes makes a sample to be detected undergo a two-stage thermal desorption process, so the concentration of the sample to be detected entering a chromatographic device is improved.