Desorbed gas amount testing device and measuring method

A desorbed gas amount testing device, comprising:

• a sample desorption tank, for storing a sample to be desorbed and providing a desorption environment for the sample to be desorbed;
• a water drain metering assembly, comprising a metering tube which is configured to display a liquid level height and receive gas desorbed from the sample desorption tank, the metering tube being connected to a draining and injecting assembly for draining water through a drain line or injecting water through an inject line, a first pressure monitoring member for monitoring a liquid pressure in the metering tube, and a second pressure monitoring member for monitoring a gas pressure in the metering tube, wherein an injecting pressure servo valve is arranged on the inject line, and a draining pressure servo valve is arranged on the drain line;
• a gas exhausting assembly, which is in communication with the water drain metering assembly and configured to exhaust desorbed gas therein;
• and
• a control system, for controlling the desorbed gas to enter the metering tube, controlling the draining and injecting assembly to drain or inject water, and controlling the gas exhausting assembly to exhaust the desorbed gas,
• wherein the control system is configured to, when the desorbed gas enters the metering tube, control a speed at which the draining and injecting assembly drains water, so that the second pressure monitoring member remains in a non-pressurized state;
• and
• the control system is further configured to, when a pressure of the first pressure monitoring member reaches a set minimum value, suspend the desorbed gas entering the metering tube, control the gas exhausting assembly to exhaust gas, and control the draining and injecting assembly to inject water into the metering tube, until the pressure of the first pressure monitoring member reaches a set maximum value.