Properties and density of natural gas

To date, natural gas is the most important source of energy. All gaseous combustible compounds from the bowels of the earth are odorless, contain a lot of impurities that affect the density of natural gas.

These gases do not have the physical parameters customary for a person - taste, color, smell - for which we are able to determine their presence. And yet they are characterized by characteristic indicators, such as: density, combustion temperature, heat of combustion, composition, maximum concentration for the explosion, pressure in the explosion.

Among the many significant physical indicators can be said about the density of natural gas. This is the value that is calculated as the ratio of the mass to its volume and is described by the formula r = m / V. The density of natural gas under normal conditions is in the range from 0.73 to 0.85 kg / m3.

Features of gas

Extracted from deposits, it consists of methane in the range of 82-98% of the total mass, often with impurities of other hydrocarbons. Combustible gas in its composition also contains incombustible substances: oxygen, carbon dioxide, nitrogen, and also water vapor. Immediately after pumping out of the bowels, the gas is freed from toxic hydrogen sulphide, bringing its content to an allowable 0.02 g / m3. The greatest density of natural gas creates the content of non-combustible mixtures of N ₂ , CO ₂ , H ₂ S or heavy hydrocarbons. The lowest values are obtained by dry methane media. It is well known that an increase in the physical value index entails an increase in the temperature of hydrate formation. Although a small weight is also able to give hydrates. At high reservoir pressure, gas is liquefied in the deposit , and this field is called gas condensate.

In comparison with other types of fuel (solid, liquid) natural gas, the density of which depends entirely on its composition, is advantageous for several indicators:

• Cheapness - as a consequence of a much easier way of extraction and transportation;
• When burned, ash and solid particles do not form;
• Relatively high rate of heat of combustion;
• There is no need to pre-prepare the blue fuel for combustion;
• Significantly simplifies the work of staff;
• The sanitary and hygienic conditions of workers are significantly improved;
• Conditions of automation of technical processes are simplified.

In everyday life there are cases when the gas pressure on the upper floors of the house risks to be more than the lower ones. This is explained by the fact that the air density index is much larger in comparison with the combustible medium. At altitude, the static air pressure decreases strongly, and the gas pressure decreases less.

Methods for measuring density

The density of natural gas is determined by laboratory methods. Due to its technical and economic feasibility, it can be calculated in the following ways:

• manually;
• With the help of tables, graphs, diagrams;
• With the use of computers and automated devices.

The most accurate method is to place the test sample in a thin-walled glass bottle with further weighing on an accurate scale. There are also special instruments that measure the density of natural gas. These are densitometers of the most diverse type - vibrational, pycnometric, acoustic, areometric, radiation and others. Among them are very well-known models Solartron 7812 and Solartron 3098. They are capable of providing continuous measurement in the flow. Typically, these models are used in systems for commercial gas accounting.