The characteristics of oil depot fire and analysis of tactics

Abstract : In recent years, the larger the single tank area of ​​an oil depot, the larger the number and loss of oil tank fire explosions compared to before 2000. After a fire and explosion, the loss is large, the rescue is difficult, and the pollution is heavy. 4 from a fire fighting depot more successful cases occurred in recent years found by analyzing large combustion fire, high heat of combustion values, severe deformation of the tank, the fire scene is complex, difficult to be fighting fire depot site characteristics; a first time extinguishing The main reason for the success of large-scale oil depot fire fighting is that sufficient strength, well-equipped, well-utilized tactics, and powerful combat support. Studying the characteristics of large-scale oil depot fires and tactics of extinguishing fires, analyzing the existing problems in the scene of large-scale oil depot fire fighting and proposing relevant measures are of great value and significance to reducing the loss of oil storage fire accidents.

Keywords : oil depot fire ; amount of fire extinguishment ; tactics ; combat security

0 Introduction

In recent years, frequent oil depot fire, only 2010 - two years between 2011 took place from 11. New single tank area and production are mostly 100,000 150,000 M3 or M3 specifications, once the combustion explosion, high calorific value, fighting difficult, high-impact, large losses. The leakage of crude oil from the oil spill of the “ 7 • 16 ” oil depot in Dalian, Liaoning province amounted to 4,000 tons, causing 50 square kilometers of sea pollution in the nearby sea area . In addition to dispatching large numbers of people and vehicles, the use of fire extinguishing agents is estimated to have a water consumption of about 60,000 tons on the day and a foam volume of about 1,000 tons. In-depth study of the characteristics of oil depot fire fighting and tactics, is of great significance to reduce economic losses and reduce environmental pollution.

In this paper, 2007-- selected PetroChina Dalian Bonded Zone International Logistics Co., Ltd. depot "7 • 16" fire, Pudong New Area, Shanghai Branch of China Petrochemical Takahashi refining segment "5 • 9 2011 National Fire firefighting force to report on wars seminar materials "Fires, four fires of 12 • 6 "fires from Huayuan Petrochemicals Co., Ltd. of Tianjin Huayuan Petrochemical Co. , Ltd., and " 12 • 18 " fires from Zhejiang Huachen Energy Co., Ltd. discussed the characteristics of oil depot fires and the tactics of fire fighting. These four fire cases have been reported and discussed as a typical case in the national firefighting team's firefighting training seminar class due to the large scale of the fire scene, the high level of the on-site commander, and the successful execution of the fighting. The highest commander of the " 7 • 16 " fire in Dalian is the deputy minister of public security, the " 5 • 9 " in Shanghai and the " 12 • 06 " fire commander in Tianjin is the standing member and head of the municipal party committee, and the highest commander of " 12 • 18 " fire in Zhejiang . It is the leader of the municipal government and the head of the company.

Overall overview of 14 fires

With the development of China's chemical industry and the implementation of the National Crude Oil Strategic Reserve Project, the capacity of single tanks for oil ( gas ) storage tanks is increasing, and the large-scale development of oil ( gas ) tanks has become an inevitable trend of development. The four largest reserves of oil depot caught fire from a total of 7,574,500 M3, also the smallest 20000 M3, fire explosion of radiant heat and fire flowing around a huge threat to the oil tank. The overall situation of the 4 fires is shown in Table 1 .

2 4 scene characteristics of oil depot fire

2.1 The fire area is large and the combustion heat value is high

After four tank fires ignited at the fire site, the flames evacuated from a dozen meters to several hundred meters. The temperature reached as high as thousands of degrees. Radiant heat and shock waves pose a great threat to the surrounding tanks and pipelines. In Table 1, the sudden explosion of the oil in tank No. 1613 of the Shanghai Gaoqiao Refining Business Unit resulted in the complete combustion of the tank, resulting in a distance of 20M. The 1615 tank wall burns out of shape. Dalian after the "7 • 16" explosion of fire accident, the scene more than 100,000 M3 of crude oil storage tanks around the oil pipeline blown off a large area around the tank fire flow, resulting in more tanks and liquid chemicals storage area Fire is a serious threat. Tianjin Huayuan Oil Tank Caused by Gasoline Leakage Caused by Gasoline Leakage and Detonated a 100m3 Fuel Delivery Platform High gasoline canister. Zhejiang Huachen Energy's propellant tank explosion caused multiple cracks at the bottom of the tank, and the tank body leaked and burned. This tank area was in a state of full three-dimensional combustion.

In addition to the above four fires, apart from Shanghai's " 5 • 9 " fire, the other three fires caused secondary fires. Flowing fire spreads rapidly along oil pipelines, pipe trenches, sewage drains, and slopes, causing adjacent oil pumping stations, crude oil metering houses, pipelines, and manifolds to catch fire, and quickly spread to other areas with lower ground. After the " 7 • 16 " fire broke out in Liaoning , oil products flowed into the downhole wells and sewage disposal wells, and the crude oil that entered the underground space burned along the drainage and sewerage pipes into the waters of the dock, causing more than 10,000 m2 of sea surface bonfires, which seriously threatened ships docked at the docks. And tanker. The whole scene in a short time to form a total area of about 60,000 m2 of huge flames.

2. 2 Oil vapor accumulation

After the fire and explosion accident occurred, under the action of high temperature, the oil in the tank and the pipeline evaporates in large quantities, the oil vapor quickly accumulates, and the pressure continuously increases, causing frequent explosions in different subregions. At a complex site where explosion and combustion coexist, a large number of oils are blown and burned, and the fire expands instantaneously.

2. 3 collapse of the tank on fire

During long-time baking of the fire, the tank wall is heated and deformed, and the various parts of the tank are unevenly deformed and curled to form multiple independent combustion zones. The fire extinguishing agent is difficult to reach and the difficulty of extinguishing is increased.

2.4 The fire noise is big

Disaster site noise sources are: oil burning sound generated; and howling tank wall friction generated when oil leaks; the sound of fire engines in the field work issued; the sound of the on-site process equipment operation; the scene fighting sound personnel . These sounds often add up to more than 90 decibels.

3 fire fighting tactics analysis

3.1 Fire power output

The four fires were comprehensively evaluated from several aspects such as economic loss, casualties, time to save, and on-site disposal. These were considered to be successful fire fighting cases in which the fire-fighting forces dealt with oil depots in recent years. Through analysis, it was found that one of the important reasons for successful combat was to mobilize enough fire fighting power at the first time. Table 2 shows the fire fighting power invested by the fire brigades for the first time during the 4 fires.

3. 1. 1 Firefighters dispatched

After the fire broke out, Shanghai, Tianjin, Dalian, and Jiaxing all started the disposal plan for major disasters in the first time. In the event that the fire in Dalian first dispatched 1,000 firefighters, the Liaoning Corps sent more than 1,380 officers and men. In the reinforcement fire scene, more than 400 officers and men in Shanghai rushed to the scene, and the other two cities dispatched 300 and 421 firefighters. At the same time, Shanghai, Liaoning Province and Zhejiang Province have mobilized the strength of full-time fire brigades. The first time to mobilize enough manpower to form a core strike force in a short time, can quickly and reasonably select the water source and offensive route, meet the needs of large-flow liquid supply in front of fire extinguishing, ensure uninterrupted water supply at the rear, and ensure the effective control of the development of the disaster at the first time. .

3. 1. 2 Fire equipment dispatch situation

The Liaoning Provincial Fire Corps deployed 348 fire fighting vehicles. The Shanghai Fire Corps fired a total of 107 vehicles , including 30 foam cars . Tianjin Fire Corps dispatched 47 fire fighting vehicles and Zhejiang dispatched 74 fire fighting vehicles.

The equipment used for these fires was equipped with high-performance foam tankers and long-range, high-volume foam cannons and mobile water cannons as the main offensive vehicle equipment. In particular, high-power bubble car to the scene of a one-time mobilization of a multi-directional flow foam fire control provides a range of support and protection, four fire calls as Signa, Rosenbauer foam-Asia and other high-power water tankers (Signa Supply flow rate 7200 liters / minute, Lucenboia supply flow rate 10,000 liters / minute ) , on-board guns ( range of more than 70 meters ) , compressed air foam car, high-emission fire engine, large-tonnage tank fire engine and advanced and practical foam Liquid transfer pumps, remote self-oscillating foam guns, mobile water cannons and other advanced equipment and equipment. According to statistics, the Dalian Branch’s remote water supply system has a flow rate of up to 22,000 liters per minute , and the longest distance for water supply can reach 6 kilometers . During the process of the explosion fire accident, the entire water supply was uninterrupted and the site took nearly two-fold. One's water supply played a major role.

3.2 The application of fire tactics

3. 2. 1 Long-distance combat

After the 4 tank fires and explosions occurred, except for the storage tanks of Zhejiang Huachen Energy Co., Ltd., the remaining three tank fixing facilities failed. The fixed fire-fighting facilities of the oil tank itself have failed, the flame temperature is high, the firefighters cannot approach the fight, and the entire cooling and extinguishing can only be carried out through mobile fire-fighting equipment. Dalian PetroChina International Storage & Transportation Co., Ltd. used 30 vehicle guns and moving cannons on the fire site and used 31 foam pipe guns ; 28 guns and moving guns were used in the Shanghai Gaoqiao Refining Group fire department ; Tianjin Huayuan Petrochemical Petroleum Co., Ltd. fire site mobile artillery, guns vehicle, high spray guns 5, 4 gun foam tube; a robot; Zhejiang Huachen energy Limited mobile artillery fire, the vehicle-mounted guns, high spray gun 24 is fixed co-gun, three guns foam tube . Long-distance combat not only ensures the firefighters' own safety, but also ensures the high pressure and flow of fire extinguishing agent. Currently fighting large-scale chemical fires, long-range operations have become the preferred tactics.

3. 2. 2 Use different treatment methods at different times

The four tactics of fire suppression were implemented with the tactics of "cooling and suppressing explosions, shutting off valves and shutting off materials, and concentrating troops to fight annihilation." In the initial stage of fire disposal, the commanding department took measures to extinguish the fire by means of cooling and detonating and closing the valve according to the fire scene. All four fire commanders sent fire fighting teams, and under the guidance of the technical staff of the unit, they closed the valves and closed the tanks. At the same time, they set up water guns, moving water guns, and foam guns to cool the cupping tank and adjacent tanks. Explode and eliminate surface fire. Effectively blocked multiple explosions in oil tanks and pipelines and increased the risk of fire. During the middle stage of fire suppression, the four fire headquarters commanded the strategy of continuous cooling, overcoming difficulties, and protecting key points according to the fire situation at the scene to ensure that the fire was basically controlled ; at the end of the fire fighting, when the on-site vehicle equipment personnel were in place, the preparation of foam fire extinguishing agents was adequate. The rear water supply lines have all been formed. When the time is ripe, a total attack is launched and the troops are concentrating on combat.

3. 3 combat protection

In the 4 fires, Dalian PetroChina International Storage & Transportation Co., Ltd. fire-fighting time was 15 hours and 33 minutes. Shanghai Gaoqiao Refining Business Department fire-fighting time was 3 hours and 16 minutes. The disposal time was as long as 17 hours. The operation time was long and the demand was guaranteed. Big. In the fight against fire, on-site vehicle fuel, fire-fighting and rescue equipment, foam liquid, and personal protective equipment are adequately supplemented. The two generals have set up supplies for life supplies, which ensured the needs of war officers, soldiers, catering, and medical care. The operation time of tank fires in Tianjin Huayuan Petrochemical Petroleum Co., Ltd. and Zhejiang Huachen Energy Co., Ltd. is approximately two hours, and no living material supply station has been established. However, after the fire, public security, transportation, urban construction, medical care, Environmental protection, electricity, and other social linkage units have also arrived on the scene and coordinated operations, playing an active role in the smooth implementation of various fire fighting measures.

4 Problems in Extinguishing Fire at Oil Depot

4. 1 Large fire noise, communication equipment can not meet the needs of on-site command

The noise at the scene of oil depots at oil depots often exceeds 90 decibels, fire fights are put into combat forces, and there are many command levels. Communication equipment is difficult to meet the communication needs of large-scale joint operations, and this leads to a certain degree of communication command. Taking these four fires as an example, there are several hundred people at the scene, and as many as several thousand people, the frequency and signal strength of communication equipment cannot meet the demand.

4. 2 personal protection awareness is not strong, inadequate protective equipment

The long time for the oil depots to be disposed of and the physical exertion are heavy. Combatants’ perceptions of long-time combat are gradually numb. For comfort, some combatants do not wear air respirator or wear irregularities, resulting in slight poisoning ; at the same time, there is also a concentration of the first output power. Empty air speed can not keep up with the phenomenon.

4. 3 Cross-regional Operations, Insufficient Coordination and Communication

The fire extinguishing of these several fires was to mobilize personnel from the province's ( city ) firefighting police force and cooperation units. At present, in the handling of large-scale disaster accidents, the leaders with the highest administrative positions on the site are generally appointed as the general commanders, and grades are commanded and implemented according to industries and departments. This model may lead to frontal combat units accepting multiple tasks at the same time, and the combat personnel will be at a loss . Second, too many command levels will lead to information delays and lags, resulting in low efficiency of on-site operations.

5 measures

5. 1 Strengthen the construction of on-site communication command system

At present, the disposal of large-scale disaster accidents places great emphasis on the tactical use of “first-time investment.” Since the first time to invest in the fighting power, command level, and therefore the communication command is particularly important. The communications dispatching and command of large-scale operations must be planned and coordinated. In addition to electronic communication technology, on-site instructions and information can also be issued in a timely manner using semaphores, sign language, trumpet numbers, and large-screen displays. The Liaoning Corps adopted a semaphore and large-screen display method with good results.

5. 2 emphasis on personal protection of firefighters

The guiding ideology of “doing personal protection well is the basis for carrying out firefighting and rescue operations” should be followed, and the self-protection awareness and protection training of combatants should be strengthened, logistics support for protective equipment should be well done, and non-combatant staff reduction should be eliminated.

5. 3 Scientifically Equipping and Using Special Vehicles

During the disposal of these fire accidents, the deployment and use of advanced equipment such as high-power, large-flow, large-tonnage vehicles, remote-controlled moving guns, and other advanced equipment enabled the long-distance combat tactics to be successful. The deployment of special equipment and frequent tactical drills by large-scale oil depots and special fire-fighting brigades based on the capacity of oil depots is an important measure for dealing with oil depot fires.

5. Cross-regional and large-scale regiment operations require multiple drills

Due to the large area of ​​fires in large oil depots, it is difficult to fight fires, and a large number of people, vehicles, and fire extinguishing agents are required. Therefore, similar to this type of fire, fire fighting troops often adopt tactics of cross-regional operations. The large-arms regiment has the characteristics of investing more troops, long combat time, and difficulty in command and coordination. Therefore, the cooperation areas should aim at the overall advancement of commanding power, total attack power, foam injection coverage, cooling water gun position setting, long-distance relay water supply protection, and coordinated cooperation of socially-linked members, and so on. In particular, key issues such as the command hierarchy should be assigned to posts and drilled repeatedly.

5. 5 Role of Fire Fighting Facilities in Oil Depots

There are power distribution rooms, fire pump rooms, fire fighting pools, foam tanks and other facilities in the reservoir area. If a fire is started for the first time after the fire in the oil depot, the fire protection facilities on the tank can be used to control the development of the fire in a timely manner. The spread of fire reduces economic losses and reduces the difficulty of fighting. However, in recent years, many fires in oil depots have shown that due to the continuous increase in the single tank area of ​​oil tanks, the overall layout of the reservoir area is compact, and the fire protection spacing prescribed by the regulations has been difficult to meet the requirements for fire fighting and protection after fire. Therefore, it is necessary to revise the design specifications and building codes of oil depots in due course.

6 conclusions

After the fire and explosion accident in the oil depot, the temperature of the fire field is high, the burning area of ​​the fire field is large, the concentration of oil vapor is high, the tank body and related systems are damaged and deformed seriously, and the fire field is of high noise, which makes it difficult to save. When analyzing the factors of the success of the four fire suppression operations, it was found that sufficient fire fighting power was mobilized at the first time and that it was possible to suppress the fire and control the disaster in a short time. This was the key to successfully extinguishing the fire ; the proper use of the fire tactical tactics prevented the fire. The occurrence of continuous explosions and the contagion of fires are important factors . Adequate warfighting and supplies support is the basis for long-term, high-intensity cooling, control of fires, and control of secondary disasters.

This article from the "China's production safety science and technology" in January 2013 the first period, re-edited by China Rescue Equipment Network, if infringement please contact us.