Analysis of the main causes of accidents that occurred on the main gas pipelines. Accident on the main pipeline

On November 3, a fire started in the area near the settlement of Almazovo, Moscow Region, of high pressure "Oborniki-Schitnikovo". The height of the flame reached up to 10 meters.
According to preliminary data, three settlements can be without gas supply - Balashikha, Monino, Chernaya.
In the garden partnership "Almaz-1" Shchelkovsky district.

October 19 in the city of Izhevsk, on an underground high-pressure gas pipeline, the pipe was damaged by a contractor who was working on the improvement of a pedestrian crossing. As a result of the accident, two districts of the city with a population of about 110 thousand people (the population of Izhevsk is about 600 thousand people) and 31 industrial enterprises were left without gas.

10 September in Moscow in the region of the 89th kilometer of the Moscow Ring Road during work on pressure testing of gas pipeline pipes by a team of gas service workers. Three people died as a result of the accident.

On the night of May 18 on the section of the main gas pipeline Mozdok-Kazimagomed in the Kizilyurt district of the Republic of Dagestan. As a result, the cities of Kizilyurt and Khasavyurt, as well as a number of settlements in the Kizilyurt, Khasavyurt and Kazbek regions of the republic were left without gas. There are no victims.

26 April happened on the Dmitrov highway in Moscow. During pressure testing of a new gas outlet in house 64, an explosion of compressed air occurred. One person died, two passers-by and a foreman at Gazteplostroy were hospitalized with injuries of varying severity.

2009
September 28 there was a breakthrough of the main gas pipeline in the region of the 32nd kilometer of the Novorizhskoye highway in the near Moscow region. occurred as a result of the fact that the driver of the car lost control and crashed into a gas pipeline valve. As a result, there was a strong fire, the man died. Due to the accident, two hospitals were left without gas, the gas supply to 1095 cottages, 200 apartments and seven boiler houses was temporarily stopped.

On the night of 9 to 10 May on Ozernaya Street in western Moscow, recognized as the largest in the post-war history of the capital. It took more than 15 hours to extinguish it, five people were injured, more than 80 vehicles were burned and damaged. According to Rostekhnadzor specialists, the explosion on the gas pipeline was caused by violations during construction in 1980 and during repairs in 1996, as well as poor-quality material from which the pipeline was made.

2008
February 17(Novgorod region). When the gas pipeline ruptured, gas caught fire and a significant flame ejection occurred. Flames from the gas pipeline set fire to three buildings located at a distance of about 200 meters from the rupture site. Two private houses were completely destroyed. They were inhabited by 11 people, among whom were several children. Two residents of the burnt houses needed medical help due to the stress they experienced. One of them was hospitalized in the Valdai Central District Hospital. As a result of the accident, traffic on the federal highway Moscow - St. Petersburg was blocked for almost two hours.

13th of January As a result of an explosion on the main gas pipeline in the Tosninsky district of the Leningrad region, a fire broke out. At the time of the fire, the height of the fire column reached 100 meters. At the time of the localization of the fire, about 0.5 hectares of the territory surrounding the gas pipeline burned out. There were no victims or injured.

2007
On the night of 26 July an explosion and fire occurred on the main gas pipeline in the Vsevolzhsky district of the Leningrad region at the site of the Severnaya CHPP (Petersburg) - Lavriki (Leningrad region). The gas pipeline is part of the unified gas supply system for St. Petersburg and the region. The accident was accompanied by a strong emission of flame and smoke, which took the form of a mushroom, which caused panic among the inhabitants of the city. In the area of ​​the incident, a forest and peat bogs on an area of ​​about two hectares caught fire. 25 fire brigades were involved in the fight against the fire. There were no casualties.

The material was prepared on the basis of information from RIA Novosti

Federal Agency for Education

Saratov State

socio-economic university

Department of Life Safety

abstract

"Accidents on pipelines".

UEF first-year students

Grigorieva Tamara Pavlovna

Head: Associate Professor of the Department

Bayazitov Vadim Gubaidullovich

Saratov, 2007.

Introduction.

1. General information on the state of the pipeline system in the Russian Federation in 2008;

2. Accidents on oil pipelines;

3. Accidents on the gas pipeline;

4. Accidents on the water supply;

5. Consequences of accidents on pipelines;

6. Self-rescue and rescue of victims of fires and explosions on pipelines;

Conclusion.

Bibliography.

Introduction:

In terms of the length of underground pipelines for transporting oil, gas, water and wastewater, Russia ranks second in the world after the United States. However, there is no other country where these pipelines are so worn out. According to experts of the Ministry of Emergency Situations of Russia, the accident rate at pipelines is increasing every year, and in the 21st century these life support systems have become worn out by 50-70%. Leaks from pipelines bring enormous economic and environmental damage to the country. A particularly large number of accidents occur in cities as a result of water leaks from worn-out communications - sewer, heating and water supply networks. From the destroyed pipelines, water seeps into the ground, the level of groundwater rises, sinkholes and subsidence occur, which leads to flooding of foundations, and ultimately threatens to collapse buildings. Foreign experience shows that this problem can be solved if plastic pipes are used instead of steel pipelines, and the laying of new ones and the repair of worn ones is carried out not in an open, but in a trenchless way. The advantages of repairing pipelines using the trenchless method are obvious: repair costs are reduced by 6-8 times, and work productivity increases tenfold.

There is a process of gradual transition from traditional building materials to new ones. In particular, when laying and reconstructing pipelines, polymer pipes are increasingly being used. Compared with steel or cast iron, they have a number of indisputable advantages: ease of transportation and installation, high corrosion resistance, long service life, low cost, smoothness of the inner surface. In such pipes, the quality of the pumped water does not deteriorate, since due to the hydrophobicity of the surface, various deposits do not form in them, as happens in steel and cast iron pipelines. Plastic pipes do not require any waterproofing, including cathodic protection, they provide continuous transportation of water, oil and gas without high maintenance costs.

The experience of reconstruction and construction of underground utilities in Chelyabinsk indicates that the use of advanced trenchless technologies can significantly reduce the cost and simplify such work. This is especially true for the central districts of the city, where the work of laying pipelines in the traditional trench way is associated with significant difficulties: these works often require the closure of passages, changing the routes of urban transport. Numerous approvals from various organizations are required. With the introduction of the latest technologies, it became possible to carry out the laying of pipelines and utilities without opening the surface and the participation of a large number of people and heavy construction equipment. Thus, the movement of urban transport is not disturbed, work on the installation of bypasses, transitional bridges is excluded, which is especially important for a city with dense buildings and a high level of traffic. Due to the absence of inconvenience and inappropriate costs (compared to construction in trenches, labor costs are reduced by about 4 times), the use of these technologies is very effective. In many cases, the use of modern technologies makes it possible to abandon the construction of new communications and, through reconstruction, completely restore and improve their technical characteristics.

The use of the latest technologies in underground construction is designed to solve the main problem - to improve the quality of underground facilities under construction and ensure the safety of their operation. The city government pays close attention to this issue. Only specialized organizations that have the appropriate license are allowed to work. At all stages of construction, multilateral monitoring is carried out, which provides data on the progress of the project and changes in the environment, constant monitoring of changes in the level of groundwater, settlements in the foundations of nearby buildings, and deformation of the soil mass is carried out.

1. General information on the state of the pipeline system in the Russian Federation in 2008

The field pipeline systems of the majority of oil producing enterprises in Russia are in a pre-emergency state. In total, 350,000 km of infield pipelines are in operation on the territory of the Russian Federation, where more than 50,000 incidents leading to dangerous consequences are recorded annually. The main reasons for the high accident rate in the operation of pipelines are the reduction in repair capacity, the slow pace of work to replace expired pipelines with pipelines with anti-corrosion coatings, as well as the progressive aging of existing networks. More than 100,000 km of field pipelines are operated at the fields of Western Siberia alone, of which 30% have a 30-year service life, but no more than 2% of pipelines are replaced per year. As a result, up to 35,000–40,000 incidents occur each year, accompanied by oil spills, including into water bodies, and their number is increasing every year, and a significant part of the incidents are deliberately hidden from registration and investigation.

The accident rate at the facilities of the main pipeline transport decreased by 9%. The system of main oil pipelines, gas pipelines, oil product pipelines and condensate pipelines operating on the territory of the Russian Federation does not meet modern safety requirements.

In the process of reforming the economy and as a result of changes in the oil markets, there is a constant decrease in the volume of financing for new construction, overhaul, reconstruction, modernization, maintenance and current repairs of physically worn out and obsolete trunk pipeline facilities. The development of new equipment, instruments and technologies for flaw detection of pipelines and equipment, as well as the development of new regulatory documents and the revision of outdated ones are extremely insufficiently funded.

There is no legislative basis for state regulation of the safety of the operation of main pipelines, in connection with which there is a need to adopt a federal law on main pipelines. The development of this law, which began in 1997, has not yet been completed.

In the Russian Federation, the total length of underground oil, water and gas pipelines is about 17 million kilometers, while due to constant intense wave (pressure fluctuations, water hammer) and vibration processes, sections of these communications have to be constantly repaired and completely replaced. The issues of corrosion protection for the oil, oil and gas production, processing and transportation industries are very relevant, due to the metal consumption of oil storage tanks and other structures, the presence of aggressive environments and harsh operating conditions for metal structures. The losses caused by water hammer and corrosion amounted to several hundred billion dollars for the Ministry of Fuel and Energy of the former USSR and about 50 thousand tons of ferrous metals per year. With the general dynamics of accidents, according to experts, the causes of pipeline rupture are:

60% of cases - water hammer, pressure drops and vibrations

25% - corrosion processes

15% - natural phenomena and force majeure.

During the entire period of operation, pipelines experience dynamic loads (pressure pulsations and associated vibrations, water hammer, etc.). They occur during the operation of injection units, actuation of shut-off pipeline valves, accidentally occur due to erroneous actions of maintenance personnel, emergency power outages, false operation of process protection, etc.

The technical condition of pipeline systems operated for 20-30 years leaves much to be desired. The replacement of worn-out equipment and pipeline fittings has been carried out at an extremely low rate over the past 10 years. That is why there is a steady tendency to increase the accident rate in pipeline transport by 7-9% per year, as evidenced by the annual State reports "On the state of the environment and industrial hazards of the Russian Federation."

Pipeline accidents have become more frequent, accompanied by large losses of natural resources and widespread environmental pollution. According to official data, only oil losses due to accidents at main oil pipelines exceed 1 million tons per year, and this does not take into account losses due to breaks in infield pipelines.

Here are just a few examples of oil pipeline accidents in 2006:

As a result of a major accident at the Druzhba main oil pipeline in the Surazh district of the Bryansk region, on the border with Belarus, the terrain, water bodies and lands of the state forest fund were contaminated with oil. The deputy head of Rosprirodnadzor noted that since the spring of 2006, 487 dangerous defects have been discovered in the section of the Druzhba oil pipeline, where the accident occurred. Pipeline corrosion was the cause of the oil pipeline accident.

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Gas pipeline accidents can lead to serious consequences for both people and the environment. In addition, during accidents, gas is lost in the area between the two taps. Gas consumers, who are forced to stop their production or use other types of fuel, suffer great material damage. The costs resulting from a gas pipeline failure can be more than 30 times higher than the costs required for repair work. In the event of an oil pipeline failure, oil leaks in the area between two valves. This leads to large losses of oil and pollution of the environment, and in some cases to the shutdown of the oil field or refinery.

A gas pipeline accident is considered to be a partial or complete rupture of the pipeline with the release of gas into the environment.

In the event of a gas pipeline accident with gas escaping to the earth's surface, it is necessary to immediately turn off the gas and take urgent measures to eliminate the accident.

The causes of gas pipeline accidents can be poor-quality welding, overvoltages in the metal due to improper laying of the gas pipeline in a trench, landslides, erosion, corrosive effects of the soil, the formation of hydration plugs in winter, and others.

One of the main conditions for preventing gas pipeline accidents associated with corrosion, erosion and metal fatigue is the systematic and timely monitoring of their condition.

In the field, when eliminating accidents of gas pipelines, making repairs, the workplace of an electric welder is necessarily equipped with a wooden lounger. The main working tool of an electric welder is the electrode holder, on which the convenience of work largely depends. The holder must firmly hold the electrode, provide reliable contact and allow quick and convenient change of electrodes without touching the current-carrying and heated metal parts of the holder. The holder should have a minimum weight and a comfortable grip. The most essential part of the electrode holder design is the device for clamping the electrode. According to the method of fixing the electrodes, the holders are divided into fork, spring, clamp and screw.

The Permafrost Institute, which studied the causes of gas pipeline accidents, found that it was not the laying of the pipeline in the freezing zone that caused these accidents, but poor-quality welding of joints.

According to an expert examination conducted at the site of the Urengoy-Center P gas pipeline accident (February 1995), one of the reasons was a pipe jammed in the ground adjacent to the karst cavity.

Ots for 1 hour; t - 3 - - average recovery time of an accident of a gas pipeline with a diameter Ots h; LJ - length of the i-th section, km.

This chapter presents the results of many years of metallographic studies of various groups of pipe steels destroyed during gas pipeline accidents.

In addition to the noted documents, operating organizations also store technical acceptance documentation; welding logs, material certificates, insulation logs, test logs, etc. This documentation is referred to when analyzing the causes and [identifying the perpetrators of gas pipeline accidents. In the process of routine maintenance, these documents are not used.

RD 153-39.4-114-01. Rules for the elimination of accidents and damage on the main oil pipelines. According to the RD, all failures on the MN are divided into accidents and incidents.

An accident is a sudden spill or outflow of oil as a result of complete destruction or partial damage to an oil pipeline, tanks or other equipment, accompanied by one or more of the following events:

3. ignition of oil or explosion of its vapors;

4. pollution of rivers and other bodies of water in excess of the limits set for water quality;

5. oil leakage more than 10m 3 .

An incident on a main oil pipeline is considered to be a failure or damage to equipment at oil pipeline facilities, a deviation from the regimes of the technological process, a violation of the legislative and legal acts of the Russian Federation and regulatory documents (establishing the rules for conducting work), which may be accompanied by oil leaks of less than 10 m 3 without polluting watercourses. The incident occurs without signs of the events described during the accident, but requires repair work to restore further safe operation of the MN.

An accident on a main gas pipeline is an uncontrolled release of gas into the atmosphere or the premises of compressor stations, gas distribution stations or automobile gas filling stations (CNG filling stations), which are accompanied by destruction or damage to the gas pipeline or its other facilities, as well as one of the following events:

1. fatal injury to people;

2. injury with loss of ability to work;

3. gas ignition or explosion;

4. damage or destruction of main pipeline facilities;

5. gas losses over 10000m 3 .

An emergency leak at a main pipeline is considered to be an uncontrolled release of the transported gas into the atmosphere, the premises of the compressor station, gas distribution station or CNG station, without signs of the events described above, but requiring repair work to ensure the further safe operation of the gas pipeline.

Causes of accidents:

1. Violation of the requirements of technology and state standards in the process of pipe production.

2. Deviations from the norms for the design and construction of pipelines.

3. Failure to comply with the rules for the operation of pipelines.

4. Influence of natural phenomena.

Organizational and technical measures during emergency recovery work.

Sequence on oil pipelines:

1. construction of an earthen barn or other container for collecting oil;

2. preparation of the repair site and placement of technical equipment on it;

3. shutdown of ECP facilities;

4. opening of the emergency section and construction of a repair pit;

5. release of the emergency site from oil;

6. cutting out a defective area or applying a sleeve;

7. sealing (overlapping) of the internal cavity of the oil pipeline;

8. installation and welding of a new coil;

9. welding of holes for oil removal;

10. quality control of welds;

11. commissioning of the oil pipeline;

12. isolation of the repaired section of the oil pipeline;

13. inclusion of ECP facilities;

14. backfilling of the oil pipeline and restoration of the embankment.

To eliminate incomplete breaks in transverse joints, double-leaf clamps with a lead or rubber gasket can be used.

For small gaps in the base metal of the pipes, smooth clamps can be used that are welded to the pipe.

With a complete rupture of the transverse joints, and so on. in case of breaks in the longitudinal joints of the pipes, the damaged sections are completely removed, and branch pipes from pipes of the same size are welded in their place. To cut out damaged areas, fireless technologies are used.

Sequence on gas pipelines:

1. shutdown of the emergency section and its release from gas;

2. disabling ECP facilities;

3. earthworks for the construction of a repair pit;

4. cutting holes in the gas pipeline for installing rubber balls;

5. installation of rubber balls to isolate the MG cavity in the repaired area;

6. cutting out the damaged area;

7. welding of a new coil;

8. checking the quality of seams by physical control methods;

9. extraction of rubber balls;

10. hole welding;

11. displacement of air from the emergency area;

12. testing of the seams of the repaired section under pressure of 1 MPa;

13. application of insulation;

14. Pipeline testing at operating pressure;

15. inclusion of ECP facilities;

16. backfilling of the pipeline.

Fistulas are eliminated by welding.

The main gas pipeline "Shchebelinka-Kursk-Bryansk" passes through the territory of the Oboyansky district.
The most dangerous section is the intersection of the gas pipeline with the Psel River near the city of Oboyan.

As a result of an accident on a gas pipeline, the following damaging factors may occur:

1. air shock wave;
2. scattering of fragments;
3. thermal effect of fire.

An analysis of accidents at main gas pipelines shows that the greatest danger is fires that occur after a pipeline rupture, which are of two types: a fire in a pit (column type) and a jet-type fire in the areas of the end sections of the rupture. The initial possible explosion of gas and the spread of fragments (the impact zone is several tens of meters), given the underground laying of the gas pipeline and the various removals of objects along the route, the possible impact zones must be considered specifically for each object.
Possible thermal damage radii are shown in Table 18.

Findings:

In the event of an accident on the main gas pipeline, it is possible to ignite buildings and injure people in a jet-type fire at a distance of up to 1200 m from the accident site.

Given the significant expansion of the boundaries of the residential zone of settlements, after the completion of the construction of gas pipelines, some buildings, structures and residential buildings fall into the zone of damaging factors in the event of an accident on these main gas pipelines.

In the event of a fire (explosion of a gas-air mixture) in one of the sections of the main gas pipeline, the radius of the likely affected area can reach 0.5 km. The death of personnel, recipients of liquefied gas over 30 people and 1-3 pieces of equipment is expected. The probable number of the population falling into the emergency zone is up to 1000 people. (on the basis of violation of life support conditions). As a result of the accident, the loss of gas can be up to 100 thousand m3, economic damage - up to 7 thousand minimum wages.

V. Accidents on main oil pipelines

The oil pipeline Michurinsk - Kremenchug "Druzhba" passes through the territory of the region. The oil pipeline diameter is 720 mm. The length of the oil pipeline is 270 km. Working pressure 41 kg/cm2. Productivity is 30 thousand tons/day. The amount of oil in the pipeline is 106,845 tons, which significantly exceeds the threshold amount determined for flammable liquids (50,000 tons). The main oil pipeline for civil defense is not categorized.
Types of possible emergencies:

1. Oil spill as a result of depressurization of a linear section with subsequent ignition and possible explosion of oil vapors. Since the oil product pipeline passes at a considerable distance from settlements and industrial facilities, therefore, in the event of an explosion or fire, they will not be affected. Severe consequences are predicted at intersections with railways. In this case, failure of railways, power lines, significant economic damage is possible.

2. Spill of oil products as a result of depressurization of the underwater crossing. In this case, oil products may enter rivers (up to 1.5 thousand m3) and spread downstream, which will lead to the death of flora and fauna, pollution of the coastal strip with oil products.

The area of ​​the probable emergency zone is up to 2000 m2 on land and 48000 m2 on the river. The probable number of the population falling into the emergency zone is up to 800 people. Likely socio-economic consequences in the event of an emergency:

1. economic damage - up to 30 thousand minimum wages;
2. victims - up to 150 people;
3. violation of living conditions - up to 800 people.

When an oil spill spreads, it is possible to pollute rivers and water bodies, carry oil products to the coastline and partially disrupt the life of the population living in settlements located downstream of the rivers.

The most likely causes of oil spills are:

Accidents as a result of external/internal corrosion of pipeline walls;
accidents when exposed to high temperatures during a fire;
accidents as a result of brittle fracture at low temperatures;
accidents on pipelines and equipment during natural disasters and terrorist acts;
accidents as a result of mechanical damage;
accidents as a result of defective construction and installation works;
accidents as a result of a violation of the technology of pumping oil products.

The main processes in the spill of oil products can be:

spreading;
evaporation;
dispersion;
dissolution;
emulsification.

The following scenarios of the possible behavior of oil products in areas of accidents and spills on water are possible, depending on the season of the year:

1. Ice-free period.

Getting into a river, stream or source, oil products begin to spread, carried away by the surface current. In this case, an elongated spot is formed. In general, oil products will tend to accumulate in areas of calm water or in whirlpools in river bends, meandering rivers, streams, or other places where the speed of the current slows down. Islands of oil products can form in places where trees and debris accumulate.
The movement and removal of oil slicks from the source of the accident will be primarily determined by the speed of the river and the direction of the wind. Under the action of the current, oil products are carried down the river, and the wind will shift the spot to one of the banks.

2. Ice period.

The movement of a slick of oil products does not depend on the direction of the wind. Floating oil products, having fallen under the ice, will move along the underwater part of the ice field, which usually has an uneven surface. The mobility of oil products decreases. The speed of movement of a slick of oil products under the ice is 10-50% of the flow velocity in the near-ice water layer 0.1 m thick, depending on the roughness of the lower ice surface. At water velocities of less than 0.1 m/s, a slick of oil products under the ice cover may remain stationary.

The distribution of oil products under the ice cover can be in the form of separate drops, merge into small spots or continuous carpets. The thickness of these formations does not exceed 5-10 mm.

As ice grows, immobile oil products freeze into the ice and then remain in the ice thickness in the form of frozen drops or individual lenses.

The nature of the distribution of oil spills depends on the shape of the channel part of the river, the speed of the current and the time elapsed since the start of the accident.

Localization of emergency oil pollution of water and coastal areas

The main way to localize the spread of oil products is to install booms on localization sites. Crews of emergency rescue units leave for the installation sites of booms in accordance with the developed standard or situational plan. Technical means - booms, oil skimmers for cleaning polluted waters. On small rivers, it is allowed to create earthen dams with culverts.

During the ice period, the time of localization of a spot of oil products depends on the time it takes to make a slot and a lane in the ice. The smallest allowable thickness of the ice cover for the performance of work can be determined in accordance with RD153-39.4-114-01 (clause 5.7.39).

Abroad booms produce control of the presence of oil products. In case of detection of oil products, an additional line of booms is installed.

During the flood period, the state of the water body is typical for both ice and ice-free periods. In this case, the activities and scope of work are planned depending on weather conditions, the prevalence of signs of an ice (ice-free) period, and the condition of access roads to the localization boundaries.

The location of localization boundaries was carried out taking into account the geographical features of the area, as well as the time of approach of oil products to a specific localization boundary. The choice of localization boundary is determined by the head of the CoES depending on the conditions of the spill, the situation and meteorological conditions. Under difficult meteorological conditions, the boundaries of localization are specified on the basis of specific hydrometeorological conditions.

Carrying out ASNDR will be hampered by high temperature in the fire seat and will require the use of specialized units. Localization and liquidation of the consequences of emergencies will require the involvement of significant financial, material and human resources.