A method for measuring trace gas

Abstract

The invention discloses a trace gas flow meter and a flow measurement method. The trace gas flow meter mainly comprises a fixed cavity, a weighing cavity and a weighing sensor. The flow measurement method comprises the steps of: inflating trace gas to be measured into the weighing cavity; due to the special design of the weighing cavity, enabling the volume change of the gas in the weighing cavity to reflect the change of the liquid weight; and further measuring the weight value change of the weighing cavity by the weighing sensor so that the flow of the trace gas can be inferred. According to the invention, on the premise of nonintervention of a gas channel, the flow of the trace gas is accurately measured without being limited by the gas quantity and the flow speed, and the influence of problems of corrosion, blockage and the like of the trace gas to be measured to a measurement result can be effectively avoided.

Description

technical field [0001] The invention relates to the field of gas flow measurement, in particular to a method capable of accurately measuring trace gas. Background technique [0002] Most of the existing gas flowmeters are interventional types, such as differential pressure type, velocity type, volumetric type, vortex street, ultrasonic vibrator, thermal type and other types of flowmeters. In the passage of the gas to be measured, not only the operation is complicated, but also the direct contact with the gas to be measured will inevitably be corroded and blocked to a certain extent, which will affect the sensitivity of the intervening parts and lead to inaccurate measurement; moreover, the existing gas flowmeter can only Measure a large amount of gas with a certain flow rate or temperature, and for a trace gas with a slower flow rate (for example, only 1 ml of gas in 1 hour), the intervening parts cannot be driven to act or respond, so the measurement effect cannot be achiev...

AI Technical Summary

Problems solved by technology

[0002] Most of the existing gas flowmeters are interventional types, such as differential pressure type, velocity type, volumetric type, vortex street, ultrasonic vibrator, thermal type and other types of flowmeters. In the passage of the gas to be measured, not only the operation is complicated, but also the direct contact with the gas to be measured will inevitably be corroded and blocked to a certain extent, which will affect the sensitivity of the intervening parts and lead to inaccurate measurement; moreover, the existing gas flowmeter can only Measure a large amount of gas with a certain flow rate or temperature, but for a trace gas with a slower flow rate (for example, only 1 ml of gas in 1 hour), the intervening parts cannot be driven to act or respond, so the measurement effect cannot be achieved

[0003] At present, in the working environment of laboratory degassing chemical reaction, microbial gas production analysis, detection of leakage of sealed products, coal bed gas release, shale gas release, etc., the generated gas generally has the characteristics of small amount, slow detection time and long detection time. Corrosion, pollution, dust and other characteristics, obviously, it is difficult to accurately complete the above measurement work with the existing gas flowmeter

Images