Part Of Combined-cycle Plants Research Articles

Bench studies of the influence of operating conditions on operational safety of steam turbine air-cooled condensers at subzero outdoor temperatures

Condensation processes are widely spread in various branches of industrial production and, in particular, in electric power industry, where, according to experts' data, heat removal in thermodynamic cycles of steam turbine plants (STP) operating as part of combined cycle plants (CCP) and autonomously, in the 21st century will be exercised mainly in air-cooled condensers (ACC). At the same time, the use of ACC as a part of steam turbine units operating in climatic conditions typical for the Russian Federation (RF) determines the relevance of problems to be solved to ensure their safe operation at subzero outside temperatures. One of these challenges is to ensure long-term safe operation of the ACC, with the formation of ice on the inner surface of the heat exchange pipes minimized. To conduct the research, Steam Turbine Air-Cooled Condenser research and training stand was used. The paper presents the combined circuit and measurement diagram of the research and training stand, and gives a brief description of the design of the ACC. Experimental modes have been determined, and methods for processing experimental data and analyzing the results obtained have been developed. As part of the study, experiments were carried out on 18 steady-state operation modes of the stand. At the same time, the values of the main operational parameters of the ACС varied within the following limits: the temperature of the cooling air at the ACС inlet — from minus 11,5°C to minus 1,8°C; the cooling ratio — from 176 to 790. The relative weight content of air in the vapor varied from 0,051% to 0,12%. An analysis of the obtained results was carried out, on the basis of which a relationship was established that allows, for various negative temperatures of the cooling air at the inlet to the ACС, to determine the highest value of the cooling ratio at which its long-term safe operation is possible. An algorithm for using the obtained relationship is given.

Determination of average relative capital investment of 30–125 MW combined-cycle plants commissioned at Russian thermal power plants in 2015–2020. Comparative analysis with data obtained in 2010–2014

The present work examines average relative capital investment and fuel consumption for electric and thermal energy supply of the combined-cycle plants having 30–125 MW gas turbines commissioned at Russian thermal power plants in 2015–2020. In this work, we used general calculation methods of average relative capital investments and fuel consumption for the electrical and thermal energy supply using power equipment of thermal power plants. To assess the scope of commissioning gas turbines incorporated into the combined-cycle plants, they were classified into three groups by electrical power: 30–59 MW, 60–99 MW and 100–125 MW. The scope of commissioning gas turbines incorporated into the Russian combined-cycle plants in 2015–2020 was analysed. The average relative capital invest-ment in combined-cycle plants having 30–125 MW gas turbines, as well as the average specific fuel consumption for the electrical and thermal energy supply, were calculated. The calculations were carried out for each part of combined-cycle plants integrated into thermal power plants with a breakdown by seven Unified Energy Systems of Russia. The quantita-tive commissioning of gas turbines is compared for the periods from 2010 to the economic crisis of 2014 and after 2014 to the present: a ~2.5-fold decrease is demonstrated. A preliminary evaluation of the increase in average relative capital investment in combined-cycle plants having gas turbines of the same electric power was performed.

Problems in creation of modern air inlet filters of power gas turbine plants in Russia and methods of their solving

The main problems in creation and operation of modern air inlet paths of gas turbine plants installed as part of combined-cycle plants in Russia are presented. It is noted that design features of air inlet filters shall be formed at the stage of the technical assignment not only considering the requirements of gas turbine plant manufacturer but also climatic conditions, local atmospheric air dustiness, and a number of other factors. The recommendations on completing of filtration system for air inlet filter of power gas turbine plants depending on the facility location are given, specific defects in design and experience in operation of imported air inlet paths are analyzed, and influence of cycle air preparation quality for gas turbine plant on value of operating expenses and cost of repair works is noted. Air treatment equipment of various manufacturers, influence of aerodynamic characteristics on operation of air inlet filters, features of filtration system operation, anti-icing system, weather canopies, and other elements of air inlet paths are considered. It is shown that nonuniformity of air flow velocity fields in clean air chamber has a negative effect on capacity and aerodynamic resistance of air inlet filter. Besides, the necessity in installation of a sufficient number of differential pressure transmitters allowing controlling state of each treatment stage not being limited to one measurement of total differential pressure in the filtration system is noted in the article. According to the results of the analysis trends and methods for modernization of available equipment for air inlet path, the importance of creation and implementation of new technologies for manufacturing of filtering elements on sites of Russia within the limits of import substitution are given, and measures on reliability improvement and energy efficiency for air inlet filter are considered.

Specific features of the schematic solutions adopted in the steam turbine units produced by the Ural Turbine Works and used as part of combined-cycle plants

Specific features of the schematic solutions adopted in the steam turbine units designed and produced by the Ural Turbine Works for use as part of combined-cycle plants are considered.

New draft projects of steam turbines for combined-cycle plants

We describe the design features, basic thermal circuits, and efficiency of steam turbines developed on the basis of serially produced steam turbines at the Ural Turbine Works and intended for use as part of combined-cycle plants.

Gland seal heaters and steam jet ejectors with surface coolers used in the steam units produced by the Ural Turbine Works

The designs of coolers for gland seal heaters, as well as the main ejectors and seal ejectors, used as part of cogeneration steam turbine-based steam turbine units developed by specialists of the Ural Turbine Works are described. The design features of the apparatuses connected with the specific features of their operation as part of combined-cycle plants equipped with cogeneration turbines are shown.

Extending the erosion-corrosion service life of the tube system of heat-recovery boilers used as part of combined-cycle plants

We present the results from an analysis of damageability and determination of dominating mechanisms through which thinning occurs to the metal of elements used in the tube system of heat recovery boilers used as part of combined-cycle plants during operation and during their outages. Results obtained from putting in use a technology for making the tubes of such boilers more resistant to erosion-corrosion wear with the aid of film-forming amines are also presented. Measures are proposed on extending the service life of the tube system of heat recovery boilers used as part of combined-cycle plants and operating under the conditions of single- and two-phase flows.

Steam turbines of the Ural Turbine Works for advanced projects of combined-cycle plants

We describe the design features, basic thermal circuits, and efficiency of steam turbines developed on the basis of serially produced steam turbines of Ural Turbine Works and used as part of combined-cycle plants.

Delivery-water heaters used in cogeneration steam turbine units produced by Ural Turbine Works

The designs of horizontal delivery-water heaters used as part of steam-turbine units equipped with the cogeneration turbines developed at Ural Turbine Works are described. The design features of the apparatuses relating to the specific nature of their operation as part of combined-cycle plants equipped with cogeneration turbines are pointed out.

Coal gasification for synthesis- and IGCC-processes. Results of the development of Texaco Coal Gasification by Ruhrkohle AG/Ruhrchemie AG

From 1975 to 1986 Ruhrkohle Oel und Gas GmbH and Ruhrchemie AG developed the Texaco-Coal-Gasification process up to commercialization. Sixteen types of coal and residues of coal hydrogenation have been gasified. In this paper the results of the development works are presented and an outlook for commercial application of the Texaco Coal-Gasification process for synthesis gas generating or as an integrated part of combined cycle plant is given.