Simulation of protective devices to ensure the safety of technological processes using explosive gases

The article presents a calculation algorithm for the theoretical substantiation of the design of protective devices used for the safe operation of explosive equipment and supply lines. Mathematical modeling is applied. The development of protective devices providing explosion and fire safety of gas-flame equipment used in construction is considered. The design of protective devices providing explosive and fire hazardous gases from deflagration to detonation combustion modes and devices developed on the principle of cutting off the flame by means of mechanical actuation of locking elements: a membrane and a conical valve are presented.

Explosion and fire safety of underground gas storage objects

Underground gas storage is an element of the gas transportation system. This is the technological process of injection, offtake, storage of gas. Emergency situations associated with burst releases are possible. An absorber is potentially dangerous equipment in the location of main structures. The loss of containment and violation of operating conditions leads to explosions of high power. Analysis of accidents involving loss of containment in equipment is carried out.

Research of influence of electric insulation liquid on explosion and fire safety of high volt transformer

В высоковольтном электрооборудовании теплоотводящей и изолирующей средой служит преимущественно масло минерального происхождения, которое обладает хорошими диэлектрическими и теплопроводными свойствами, но является взрывоопасным и биологически неразложимым горючим. Многие исследователи говорят о том, что масло растительного происхождения лучше минерального с точки зрения температурных характеристик и утилизации. Но стоит отметить, что вывод о повышении пожаровзрывобезопасности электрооборудования за счет перехода на растительные масла сделан только на том основании, что температура вспышки у минеральных масел в два раза ниже. При этом совсем не учитывался фактор увеличения объема паров масла и газов в трансформаторном баке под действием дугового разряда, возникающего при межвитковых замыканиях. В настоящей статье предпринята попытка численно доказать влияние электроизоляционной жидкости на основе растительных масел на взрыво- и пожаробезопасность высоковольтного трансформатора при возникновении перенапряжений. Explosion of the transformer can occur under the influence of both external (lightning) and internal (switching, arc) overvoltages. It is necessary to carry out checks of the condition of the insulating material during operation in order to timely detect developing failures and prevent accidental failures due to partial discharges on the equipment. In high-voltage electrical equipment, and in particular in transformers, the heat-removing and insulating medium is mainly mineral oil, due to its good dielectric and heat-conducting properties, but it is combustible, explosive and biodegradable. Currently, it is of interest to use plant materials for the production of insulating liquids. In our country, this is still experimental development, which, however, has practical applications abroad. Many researchers say that vegetable oil is better than mineral oil in terms of temperature characteristics and disposal. But it is worth noting that the conclusion about the increased fire and explosion safety of electrical equipment due to the transition to vegetable oils is made only on the basis that the flash point of mineral oils is two times lower. In this case, the factor of increasing the volume of oil and gas vapours in the transformer tank under the action of arc discharge arising from inter-turn faults was not taken into account at all. This article presents an attempt to numerically prove the effect of an insulating liquid on explosion and fire safety in the event of overvoltage using a boiling point in high-voltage equipment, and in particular in transformers. The research results reflect the effect on the possibility of explosion of the transformer and its ignition of vegetable oil. As a result of calculation there was obtained the excess pressure in the transformer for two types of oils. When solving the problem, the influence of the electric energy of the arc on the volume of gases formed in the oil was taken into account. As an example, for a specific type of transformer, overpressure is determined, leading to the destruction of the tank, which indicates the practical significance of the materials presented in the article.

Requirements for explosion and fire safety of industrial enterprises

The modern requirements for explosion and fire safety of industrial enterprises are considered. Equipping the production with high-quality explosion-proof electrical equipment ensures the safety of resources and people's lives. Basic concepts are given, principles and classifications are described, international and Russian standards are indicated, which should be followed by manufacturers of such devices.

INCREASING INTRINSIC SAFETY IN PULSE POWER SUPPLY SYSTEMS OF CONSUMERS IN COMPARISON WITH DC POWER SUPPLY SYSTEMS

The purpose of the work is to evaluate the magnitude of the arc sparking energy during switching in the wires of a pulsed power supply system when compared with the energy when powered from a direct current source and to determine the flammable currents of the methane-air mixture to improve intrinsic safety. Methodology. The research methodology is based on the fundamental principles of the application of the theory of electrical engineering, the theory of planning a scientific experiment, computer and simulation modelling. The experimental data were obtained in the laboratories of the Kremenchuk Mykhailo Ostrohradskyi National University using certified metrological measuring instruments. The system was modelled using the software packages Matthcad, Microsoft. EXCEL. StatGraphik. Results. Conducted theoretical and experimental studies of the magnitude of arc sparking prove that the energy of sparking with a pulsed current is less than with a constant one and can be used as the basis for reducing the ignition of gas in mines and other explosive industries. Scientific novelty. The useful use of the consumer’s reactive energy has been substantiated if the supply line or the current source is shut off for the duration of the pause and at the same time the consumer is shunted. Practical significance. The obtained results are recommended to be used in power supply systems of consumers that operate in a pulsed mode to increase their energy efficiency and explosion and fire safety of operation.

Modern problems and main directions for ensuring explosion and fire safety of fuel preparation systems for combustion in thermal power plant

To solve the problem of further improving the efficiency and reliability of solid fuel generation in the Russian Federation, it is necessary to solve a number of main problems: ensuring environmental safety, export-oriented nature of the coal industry, low reliability, efficiency, high emissions of NOx , SO2 and particulate matter of existing obsolete equipment. In modern conditions, these problems can be solved comprehensively with the use of relatively low-cost methods in the case of using highly reactive coals, which at the same time have an increased explosion hazard (coals of explosiveness groups 3 and 4). For this reason, currently a large number of coal-fired power plants (mainly in Siberia and the Urals) experience a global transition to the combustion of highly explosive Kuznetsk coal of grades D, G, GD. In the present work, analysis is undertaken of methods and technologies to ensure the explosion and fire safety of fuel preparation systems for combustion at thermal power plants during the transition to these types of fuels, since most of these thermal power plants were initially designed for explosion-proof types of coal (T, 1CC, AH). A number of additional recommendations are developed to the current "rules of explosion safety", taking into account the specifics of technological schemes and the operation of a large number of these thermal power plants, a number of design solutions for equipment that improve the explosion safety of their dust treatment plants. For systems of preparation of finely crushed fuel (5–15 mm), boilers with circulating fluidized bed that are promising for the Russian power industry, and the use of drying installations at thermal power plants to ensure crushing of ordinary high-humidity fuels entering thermal power plants, a number of measures have been proposed that increase the fire safety of such installations.

ENSURING EXPLOSION AND FIRE SAFETY AND SAFETY AT ASPHALT PLANTS

The basic requirements for safety and fire and explosion dangerous and toxic plants for asphalt plants. The assessment of working conditions at the facilities is made subject to these requirements