Regularity Of Localization Of Fires At Energy Facilities In Uzbekistan

In the article, the author analyzes emergencies at power plants in Uzbekistan, including research by scientists who conducted their research on extinguishing and localizing fires with the use of appropriate technical means at energy facilities, taking into account the observance of safety measures for energy facilities that have the property of electric shock to firefighters. In addition, the author provides a mathematical analysis of a fire event using the multi-interval method and formulates the appropriate conclusions. At the same time, the author proposes the use of the latest information technologies in extinguishing fires of this kind.


INTRODUCTION
In the Republic of Uzbekistan, special attention is paid to energy facilities, since the fires that occur at these facilities negatively affect the entire economic infrastructure of society, including both the production and housing sectors.
They have a total value of $ 2 billion and a capacity of 2,700 megawatts 1 .
In addition, new power plants with a total capacity of 760 megawatts will be commissioned in Tashkent, Navoi, Samarkand and Surkhandarya regions.
According to the research of Doctor of Technical Sciences A.D.Ishchenko "One of the most important aspects preventing the further development of a fire that has arisen is the organization of continuous fire extinguishing from the moment the fire extinguishing agents are supplied to localization.

METHODS OF RESEARCH
To fight fires in these premises, various technical solutions are used, for example, fire safety systems in buildings and structures. The effectiveness of these solutions is considered in a relatively short period of time (10-15 minutes), although it is obvious that these solutions can sufficiently improve the working conditions of fire departments when carrying out work related to extinguishing a fire that arrived in the shortest possible time. But, as a rule, dense smoke complicates the work of the links of the gas and smoke protection service (GSPS), thereby making it possible for a fire to develop according to its own scenario.
As you know, for work in an environment unsuitable for breathing, firefighters use breathing apparatus with compressed air and compressed oxygen. Do not forget that when the GSPS link moves in conditions of dense smoke, the link speed decreases several times. Such a variant of events is possible when the GSPS link does not have time to reach the fire source. This is facilitated not only by dense smoke, but also by the insufficient time of the protective action of the DASV, which does not allow to overcome the tunnels, in view of their complex layout and length. As a result, the GSPS link was forced to leave the VAT to change the compressed air cylinders, without starting to localize the fire source. Also, with a large number of unit changes, the load on the personnel increases" 2 .
The modern development of technical means of fire extinguishing undoubtedly requires the The American Journal of Applied sciences (ISSN -2689-0992) In addition, the fire extinguishing system at the power plant also requires improvement. So, when nuclear weapons explode at an altitude of more than 30 km, an electromagnetic pulse with a field gradient of up to 50 kV/m appears near the earth's surface. Due to the wide and increasing use of low-voltage highly sensitive microelectronic and microprocessor equipment in the power industry, an electromagnetic pulse of a high-altitude nuclear explosion (HEMP) is perceived by many world armies as a promising weapon for destroying the foundations of the infrastructure of any country, i.e. electric power industry. For example, many countries have recently begun to develop protective equipment to protect electrical power equipment from HEMP. However, in addition to electronic and electrical equipment that is directly involved in the production, transmission and distribution of electricity, there is another type of highly sensitive electronic equipment that is not directly involved in these processes, but can interfere with them. These are fire extinguishing systems installed at any power plant and electrical substation 4 . If, for example, we take the accident at the Talimarjan TPP that occurred on January 5, 2021, then according to the primary data, due to the triggered technological protection, an unscheduled shutdown of the Talimarjan TPP's combined- In this regard, it is necessary to turn to the large fires that occurred in the Republic of Uzbekistan at energy facilities. For example, in 1981 at the Syrdarya SDPP, 30 working blades of the low-pressure cylinder stages broke off at power unit No. 4, which caused a fire, which led to the failure of 10 power units of the station with a capacity of 300 MW 6 . The arithmetic downtime after the accident was: for power units No. 1,2,4-1382 hours, No. 3-927 hours, No. 5-564 hours, No. 6-658 hours, No. 7-290 hours, No. 8-80 hours, No. 9 -108 hours, No. 10-27 hours. The total downtime of the power units of the Syrdarya SDPP was 4036 hours. Which corresponds to 168 working days. The reason for this fire was insufficient technical monitoring of the operation of the lowpressure turbine unit. Unfortunately, this sad fact was repeated 9 years later, namely in 1990 at the same Syrdarya SDPP there was a fire in the working blades of the last stage of the lowpressure cylinder of turbine unit No. 7, which led to a fire. Three power units of the station with a capacity of 300 MW were shut down. Turbine unit 7 was completely destroyed, and the roof of the engine room from 33 to 36 axles was also rendered unusable, including damage to the turbine generator and auxiliary equipment. Analysis of fires at energy facilities in the Russian Federation has shown that the direction of development of fire fighting equipment is also determined by the situation that develops during the elimination of fires and the consequences of emergencies. So, during the elimination of the consequences of an emergency at the Sayano-Shushenskaya HPP, it was necessary to use all the forces and means to pump water, and during the protection in 2010. from forest fires of the federal nuclear center in Sarov, it was required to supply a large amount of water to extinguish fires 7 .
Such a need determined new tasks for manufacturers of fire fighting equipment; it was necessary to develop and create pumpand-hose complexes of increased productivity. New fire-fighting vehicles produced by Velmash-service have appeared 8 :  Universal pump and hose car "Potok";  Universal pumping and hose complex of high performance "Shkval".

Fig.1.Shkval, a universal pump and hose complex of high performance
In addition, it has been established that the main danger in extinguishing fires of electrical It should be especially noted that at the country's critical energy facilities (nuclear power plants) there is a list of rooms in which power outages are unacceptable in connection with ensuring the safety of the nuclear reactor.
Therefore, fire extinguishing in these rooms should be carried out without removing the voltage from the live parts of the equipment, which is in the range from 0.4 to 6 kV 9 .
In other words, when extinguishing fires at power facilities, you should strictly adhere to this rule: if the disconnection of electrical equipment or cable is not indicated in the extinguishing permit, then they are considered energized.
Fire extinguishing at power facilities can be carried out on disconnected electrical installations that are energized; water is used in the form of compact jets from the HBK-50, HB-50 barrels and sprayed from the barrels with the NRT-5 nozzles, as well as noncombustible gases and powders. It is strictly 9 Колбасин А.А. Нормирование требований к средствам тушения электрооборудования под напряжением на объектах энергетики: forbidden to supply any foam by hand when extinguishing live installations. To avoid electric shock, personnel should not go behind the fence where switchgears and high-voltage devices are located.
According to research carried out by Doctor of Technical Sciences A.D. Ishchenko: "Another important component of the fire extinguishing system is the for fire protection of organizations, which are created in accordance with section 6 of SP 232.1311500.2015"Methods for determining the number and technical equipment of the fire protection of an enterprise for organization and implementation of extinguishing fires". In accordance with this technique, the most fire hazardous object on the territory of the enterprise is selected, characterized by the largest possible fire area and the highest flame propagation speed, and the fire development pattern in accordance with the fire load characteristic of the selected object. After that, the speed of the fire trucks to the place of the alleged fire is selected, depending on the type of road surface, and the time of the beginning of effective actions to extinguish the fire (the time interval from the moment of the outbreak of the fire to the moment the fire engine is fed to the fire) is calculated according to the formula: where tоб is the time from the moment of fire occurrence to the moment of its detection, min; tс -time from the moment a fire was detected until the moment it was reported to the fire brigade, min; tсл -is the time from the moment of arrival at the fire until the moment the first barrel is fed into the fire center (time of deployment of forces and means), min.
tр -time from the moment of arrival at the fire until the moment the first barrel is fed into the fire center (time of deployment of forces and means), min 10 .
Indeed, the proposed formula reflects the regularity of the arrival of fire rescuers at the site of the fire, taking into account the moment of its initial detection and the interval between its detection and the corresponding message about the fire that occurred to the fire and rescue service. In addition, A.D.Ishchenko takes into account such an important point as the supply of fire extinguishing agent from the first barrel and the shorter the time interval between the arrival of firefighters to the fire site and the supply of fire extinguishing agent from the first barrel, the closer the fire extinguishing effect will be to unity. Otherwise, this effect will approach zero. Thus, methodologically, the fire damage will be the least when approaching unity and the highest when approaching zero.
By the way, if we analyze the work of such a researcher as V.I. Levin, then we can be convinced of his approach to the application of a set-theoretic construction associated with the use of a multi-interval method, which consists in a paradigm reflecting that the set of all possible values of an incompletely defined quantity а~ set only by its lower (а1) and upper (а2) boundaries. Accordingly, the value а~ is written in the form of a limited uncertainty interval of the form: а~ а 1 , а 2   а а 1 а а 2  . (2) It is assumed here that the unknown "true" value of the undefined quantity а~ reliably lies within the interval [а1, а2], without going beyond its boundaries (а1) and (а2). Moreover, all values within this interval are considered "equally possible" in the sense that there is no reason to prefer one value to another. Note that in this case, the concept of equal to a possibility does not mean setting a uniform probability or any other distribution of possible values within the specified interval. Algebraic operations are introduced over intervals of the form (2), similar to the corresponding operations over numbers. For this, a settheoretic construction is used: а~ б~ а б аа~,бб~, а~а аа~, (4) 10 Ищенко А.Д. Теория локализации пожаров в зданиях объектов энергетики: Диссер. на соиск. уч. степени док-ра.техн. наук.-М., 2020 г.-С. 124.