Coal Industry

Grasys nitrogen units and plants are used to create inert environment when preserving explosive mines or fighting hard-to-reach fires with nitrogen. Within just a few hours they are capable of providing inert atmosphere in the emergency area whereupon the combustion behavior completely extinguishes.

The design of the firefighting unit permits its use for supporting constant atmospheric composition with a certain allowable oxygen concentration in the mine. Nitrogen units and plants are also used to preserve exhausted mines.

In some circumstances, nitrogen renders possible to ensure practically complete fire and explosion safety since combustion of the vast majority of substances becomes impossible in the environment with oxygen content less than 10%.

Mine preservation is a temporary mine shutdown, or suspending mining and other operations with continued possibilities of the mine working in the years to come.

When coal mines are shutdown for preservation, there is a risk of mining gas (methane, nitrogen dioxide, carbon dioxide) intrusion into groundwater, the atmosphere, and others.

Fires and explosions, spontaneous combustion of coal are as well expectative since methane is released regardless of the age and kind of rock. To prevent fires, inert nitrogen gas is used to preserve mines and control fires resulting in managing the emergency risk.

Gaseous nitrogen generation from air is one of the mainstreams in gas separation and production through the use of membrane technology. Nitrogen, which is chemically inert gas, fails to support combustion of any hydrocarbon substances.

The functional concept of gas firefighting units is to create indoor environment of less than 10% oxygen, where combustion process becomes impossible.

Gas firefighting units are not only very efficient as they are capable of extinguishing fire in a few seconds, regardless of how far the fire source is, but they are also of service-strong and low-maintenance kind. In many applications these units are the only type of equipment suitable for fighting hard-to-reach fires, such as in mines. What is more, Grasys firefighting units are useful in supporting constant inert atmosphere composition in buildings.

These and other unique qualities contribute to ever-increasing recognition and spread of the units in different branches of human activities. The combination of the recent scientific results and vast experience of the company's specialists provides the Grasys firefighting units with a variety of obvious advantages, such as:

• No damage caused to equipment.

As a result of firefighting using a nitrogen unit, no damage is caused to valuable equipment, unlike foam and water fire extinguishing systems.

• 3D fire fighting

Nitrogen firefighting units ensure 3D fire extinguishing. The efficiency of firefighting is unaffected by the fire source inaccessibility.

• Permanent inertia

The firefighting unit design permits its use for supporting constant fire and safety atmospheric composition.

• Available container configuration

The nitrogen firefighting unit can be made in container version, skid-mounted or based on chassis.

• Full automation

In the event of a fire, nitrogen from the receiver is automatically supplied to the room or process tank where the fire has started.

• Easy to operate

The units are very easy to operate with no service required. Firefighting and further receiver filling with nitrogen are unmanned operations.

• No refueling required

Unlike conventional firefighting systems, refueling is not applicable to Grasys firefighting units. If nitrogen is used for firefighting or process requirements, the unit makes up for nitrogen reserves.

• Ecological cleanliness

Nitrogen is an environmentally-green gas, so the use of nitrogen firefighting units causes no adverse environmental impact.

• Low operating costs.

Nitrogen is an effective fire-suppressant gas produced by the plant from normal ambient air as a result of which operating costs appear to be very low.

The firefighting unit design permits its use for supporting constant atmospheric composition with a certain allowable oxygen concentration in a room or a tank. This renders possible to ensure practically complete fire and explosion safety since combustion of the vast majority of substances becomes impossible in the environment with oxygen content less than 10%. Furthermore, nitrogen produced by the unit can be used to purge process volumes, in that case it is automatically made up for in the receiver.

Nitrogen is the top requested gas for ensuring explosion and fire safety in various industries ranging from food to nuclear. As an inert gas nitrogen enables to displace oxygen and avoid the oxidation reaction when being supplied to the process volume.

Combustion is a rapid oxidation reaction, which is due to the oxygen presence in the atmosphere, as well as an available ignition source such as a spark, electric arc, chemical reaction followed by substantial release of heat. To prevent inflammation this reaction has to be prevented.

In environment with nitrogen concentration of about 90% the combustion process becomes impossible. Therefore, permanent-type nitrogen units and mobile nitrogen plants manufactured by Grasys and designed to produce nitrogen ranging from 5 to 5000 m³/h are capable of effective fire prevention and, when required, firefighting.

Grasys nitrogen units and plants are in widespread use to ensure explosion and fire safety during transportation, transshipment, storage of hydrocarbons and explosive chemicals. Nitrogen is most often used to purge process equipment, tanks, pipelines, as well as to develop nitrogen blanket.