Standard method for standard gas preparation.
Standard gas is the gas industry term. A reference material is a measurement standard with uniform concentration, good stability, and accurate measurement. They have the basic functions of copying, saving and transferring measured values, are used to calibrate measuring instruments and measurement processes, evaluate the accuracy of measurement methods, test the testing capabilities of testing laboratories, determine the characteristic values of materials or products, and arbitrate measured values.
Standard gases are divided into binary, ternary, and multivariate.
Standard gas preparation methods are divided into:
Weighing method 1, scope of application, weighing method is a method recommended by the International Organization for Standardization. It is only suitable for gases and condensable components that are completely in a gaseous state under experimental conditions, and that do not react with the inner wall of the cylinder. 2. Required equipment and gas distribution equipment: vacuum pump, vacuum gauge, high and low pressure gauge, valve, gas cylinder card, chassis. Weighing equipment: high-precision balance.
Scope of application: The permeation method is suitable for the preparation of trace amount of active gas. It is a dynamic gas distribution method. 2.Required equipment and gas distribution equipment: permeation pipe, pressure stabilizing valve, steady flow system, flow meter, temperature recorder, valve, pipeline, mixing tank.
Partial pressure method 1, scope of applicationThe partial pressure method is suitable for the preparation of gas at room temperature, and the standard mixed gas content is 1 60%. Required equipment and gas distribution equipment: gas cylinder confluence, pressure gauge, valve, vacuum pump, pipeline, gas cylinder fixture.
Diffusion method 1, scope of application, diffusion method is suitable for the preparation of liquid organic gas at room temperature 2, required equipment gas distribution equipment: gas cylinders, valves, flow control valves, flow meters, liquid composition, analytical instruments, gas cylinders, fixtures.
Volumetric method 1, scope of application: The static volume method is suitable for the preparation of various small and small amounts of standard gases in the laboratory, and the pressure is close to atmospheric pressure. 2.Required equipment and gas distribution equipment: gas cylinders, gas cylinder pressure reducing valves, stator tubes, pressure gauges, vacuum pumps.
Saturation method 1, scope of application: The saturation method is suitable for gases and vapors that are easy to condense. 2.Gas distribution equipment: gas cylinders, gas cylinder pressure reducing valves, condensers, saturators, thermostatic controllers, pressure gauges, circulating fans.
Flow method 1, scope of application, flow ratio method is a dynamic gas distribution method, is a standard gas that strictly controls the flow rate of a certain proportion of component gas and dilute gas. 2. Gas cylinders, gas cylinder pressure reducing valves, check valves, flow controllers, pressure gauges, pipelines, chassis and other equipment.
Dilution method 1, scope of applicationThe dilution method is one of the methods for preparing low-content standard gases. 2., gas cylinders, gas cylinder pressure reducing valves, flow controllers, pressure gauges, pipelines and other equipment.
Volume method 1, scope of applicationThe volume ratio method is a simple gas matching method, which is calculated according to the content and volume of the required gas. The volume of the component gas and the dilution gas is controlled and the standard gas is mixed. 2. Required equipment: syringe and fixed container.