Oil and Gas Production, Processing and Transportation

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, unsupports 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 - 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 chassis-based.

• 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 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 firefighting when required.

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.

Nitrogen is used to ensure production process safety by creating inert atmosphere when purging and testing gas pipelines, performing hot works, preserving pipelines and equipment. The implicit advantage of this method is its user-friendly operation and safety as any hydrocarbon interaction with nitrogen is excluded due to its high inert properties. Nitrogen is supplied to process pipelines and CS equipment to ensure less than 1% methane content and less than 2% oxygen content in gas mixture.

The use of R&P Co. Grasys nitrogen plants for performing gas pipeline hot and gas-flame works enable to substantially improve the work performance safety, reduce the scope of preparatory operations and decrease the completion time frame. Equally important, the personnel safety should be ensured when performing repair works.

The use of nitrogen at gas facilities to displace methane, air or gas-air mixture from pipeline sections and process equipment is regulated by STO Gazprom 14-2005 “Standard Design for Hot Works Performance at the Gazprom Gas Facilities” and STO Gazprom 2-3.5-454-2010 “Pipeline Operating Procedure”.

Usability of nitrogen plants enables to safely perform scheduled and emergency hot works and ensure operational reliability of hazardous production facilities as well as occupational safety.

There are technical specifications regulating gas composition delivered for pipeline transportation. The most common reason for the imposed requirements non-compliance is the difference in hydrocarbon and water gas dew point. As of today, it is high capital and operating expenses related to gas treatment for transportation that keep a great many of small, medium and large fields undeveloped or poorly developed. There also exists gas drying challenge (primarily water dehydration) when gas is collected from underground storage facilities.

Petroleum gas treatment for transportation and delivery implies product purification process from impurities and components that impede its passage through the gas pipeline. The H2O present in petroleum gas, as well as aggressive impurities and liquid hydrocarbon compounds may result not only in decreasing gas pipeline throughput capacity, but also in equipment corrosion.

Grasys membrane units enable to essentially reduce both water and hydrocarbon gas dew point. Depending on the process implementation scheme, gas can be dried by 15–60 °С. Implementation of the Grasys technology is instrumental in reaching water DPT in line with OST 51.40–93 at the dried gas pressure of 4.0 MPa. Petroleum gas treatment with immediate removal of several impurities within one process cycle is also efficiently provided with Grasys membrane gas separation units.