Quality, size, hematocrit

That the quality of the weight of gas, often milligrams (mg), grams (g), kilograms (kg), t (t) said. Volume refers to the containers in which the gas volume. Often mm3 (mm3), cc (cm3), cubic metres (m3). Hematocrit is the unit weight of some material volume, with symbols V, units with m3/kg hematocrit gas, liquid hematocrit l / kg said.

Pressure, pressure, pressure, absolute pressure, the relative pressure

Gas molecules on the vessel wall movement at the impact of the forces generated by that pressure. Containers per unit area is the pressure generated by the pressure. Pressure on the use of customary units mm Hg (mmHg) / cm2 (cm2), the International General (Legal Metrology) Pago (Pa), kPa (kPa), MPa (MPa). The conversion 133.3Pa = 1 mmHg = 0.1333kPa, 1MPa = 1000kPa = 1000000Pao1ATA = 0.1MPao.

Surrounded by a thick layer of the Earth's surface on the surface of the Earth's atmosphere or surface caused by the pressure of objects known as the "atmosphere", symbols for B; direct role in the container or object's surface pressure, known as the "absolute pressure" absolute pressure values an absolute vacuum as a starting point, the symbol for the PABS.

With pressure gauges, vacuum table, such as U-tube instruments measured the pressure called "Table pressure" (also referred to the relative pressure), "Table pressure" as a starting point to atmospheric pressure, the symbol for the Pg. Is the relationship between: PABS == B + Pg.

Temperature, absolute temperature, relative humidity, critical temperature, critical pressure

Temperature thermal motion of material elements statistical average. Gas molecules gas temperature is the thermal motion. The units used gas temperature Celsius (℃), the temperature of ice water for 0 ℃. Physics often use the absolute temperature, "K" said. Absolute temperature to -273 ℃ as zero. Celsius and the relationship between the absolute temperature T = t +273. In addition British scientists often use "Fahrenheit" symbol oF.

Because any point in the gas temperature and can be liquefied under pressure, the higher the temperature, the pressure of liquefied need higher, but when the temperature exceeds a certain value, even if the increase in how much pressure can liquefaction, that temperature is critical temperature , in this temperature on the lowest pressure called critical pressure.

Dew point, evaporation, condensation

The gas is never saturated water vapor into the saturated steam temperature, as a non-saturated water vapor saturated steam, it is a fine of dew, the temperature at which dew there called "dew point." Dew point and pressure and therefore are atmospheric pressure dew point (pressure dew point), and under the pressure of the dew point. Dew point is that the atmospheric pressure in the atmospheric pressure water condensation temperature, dew point and pressure is the pressure of the water condensation temperature, there are conversion (available on the conversion table), such as when the pressure of 0.7 Mpa pressure dew point of 5 ℃ , the corresponding atmospheric pressure (0.101 Mpa) dew point is -20 ℃. In the gas industry, in the absence of special note, and the dew point are referred to atmospheric pressure dewpoint.

Vaporization is a liquid material from the process gas, including boiling and evaporation. Gas Condensate is a liquid process.

Purity

Gas purity is an important technical parameters. Nitrogen cite as an example, according to GB nitrogen purity nitrogen into industrial use, and high-purity nitrogen purity nitrogen 3, they were the purity of 99.5% (O2 less than or equal to 0.5%), 99.99% (O2 less than or equal to 0.01 %) and 99.99% (O2 less than or equal to 0.001%).

Flow, volume flow, mass flow

Flow refers to the process gas flow in the unit time of the adoption of a cross-section of gas. There are two ways to flow, volume flow and quality of that flow. The former refers to a section of the pipeline gas volume, the latter through the quality of the gas in the gas industry in general are used to volume flow m3 / h (or L / H) for the measurement units. By gas volume and temperature, pressure and humidity relevant for the purposes of comparison usually refer to the volume of traffic that is the state standard (temperature is 20 ℃, 0.101 Mpa pressure, relative humidity of 65%), the flow at this time to Nm3 / h unit, "N" means that the state standards.

Compressed air

Compressibility of air, the air compressor mechanical power to do their smaller size of the increase in air pressure is compressed air. Contains many impurities in the air: 1. Water, including water spray, water vapor, condensation water; 2. Oil include: oil, oil vapour, 3. Various solid substances such as: Rust mud, metal powder, rubber powder, tar tablets and filters, sealing materials Ximo; In addition, a variety of harmful substances such as chemical smell. Compressed air through pressure, cooling, adsorption method to remove one of steam. Through heating, filtration, separation methods such as mechanical removal of liquid water.

Adsorption, membrane permeability

The adsorbed gases in one or more components in the surface of porous solid selective enrichment, is adsorbed component called adsorption media, as porous solid adsorbent. Adsorbent and adsorption media connectivity is the chemical bond, and adsorption media analysis on the temperature increase or decrease in pressure concerning the composition pressure. Another component is adsorbed to the solid adsorbent chemical reaction, known as chemical adsorption, chemical adsorption under normal circumstances can not be renewable.

Membrane permeability in the gas purification process that the polymer is based on a separation of gas or gas component from the side of selective membrane permeability to the other side. The components dissolved in the polymer membrane surface, and along the membrane formation of a transfer concentration difference, and maintain this concentration is on the poor side of membrane components pressure higher than the other side of the membrane component of the pressure.

Common statutory gas measurement units

According to the State Council on February 27, 1984 "on China's reunification in a statutory order unit of measure" establishment

Official measurement units: SI units

Statutory units of measurement: the International System of Units of the non-flat