Use of various methods for suppressing internal corrosion of the thermal network at the Novomoskovsk state regional electric power plant

The results of using several water-chemical regimes for the thermal network (pH = 8.3–9.0; pH greater than 10; pH = 8.6–8.9 in the presence of a corrosion inhibitor) are reported. The rates of internal corrosion under these regimes are estimated. The regime with pH = 8.6–8.9 and a corrosion inhibitor and the regime with pH greater than 10 are found to produce the same effect. Translated from élektricheskie Stantsii, No. 10, October 2008, pp. 36–38.     

Internal-corrosion inhibitors for pipelines in heat-supply systems carrying water with a high oxygen content

The reliability of heat-supply systems is determined primarily by internal corrosion of the pipelines. The concentration of oxygen in the water exerts a major influence on the corrosion. In systems with a standard oxygen content, OéDF-Zn is a highly effective corrosion inhibitor. However, there are systems in which the quality of deaeration of the make-up water of the heat-supply system is low (or deaeration is nonexistent), and the concentration of oxygen is considerably above the standard value. Classed among these systems, for example, are the HWS systems, which are incorporated into closed heat-supply systems. The oxygen concentration in these systems is analyzed to assess the situation. __________ Translated from élektricheskie Stantsii, No. 6, June 2007, pp. 35–39.     

On the water-chemical regime in steam generators at NPP

The effect of the water-chemical regime (WCR) on damage sustained by heating surfaces of steam generators at NPP is analyzed. It is indicated that phosphate treatment with minimal excesses of phosphates in the steamgenerator water is the most optimal method of managing the WCR regime of horizontal steam generators. __________ Translated from élektricheskie Stantsii, No. 5, pp. 15–21, May, 2006. In order of discussion (The editor).     

Behavior of phosphates in a high pressure drum boiler with frequent loading

The overall contamination of the baffle pipes in a high pressure drum boiler in the phosphate water-chemical regime is estimated based on the increase in the concentration of phosphates in the boiler water during unloading of the boiler to approximately 50% of nominal. Translated from élektricheskie stantsii, No. 6, June 2008, pp. 29–33.     

Advancement of design of friction bearings for powerful steam turbines produced by the LMZ company

Results of studies aimed at advancing the design of friction bearings of power steam turbines are presented. Brief information on tests of systems of hydraulic lifts of the shaft and modification of oil seals and bearings with modified antifriction alloys is given. The efficiency of the use of bearings with advanced design in turbine sets is discussed.Translated from Élektricheskie Stantsii, No. 9, September 2004, pp. 15 – 20.     

Conversion of Toxic Components of Flue Gases of Cogeneration Plants

A method for conversion of toxic components of flue gases (NO _x and SO _x ) by intense ozonization and pulse treatment is suggested. Ozone-oxygen mixture produced from atmospheric air is ejected into the flue in the zone of pulsed positive corona. __________ Translated from Elektricheskie Stantsii, No. 8, August 2005, pp. 38 – 41.     

Increasing the corrosion resistance of equipment due to the use of film-forming amines

Results of a study of tube specimens cut from hot-water boilers show that film-forming octadecyl amine (ODA) used in the process of preservation removes deposition from the surface of the metal. An ODA film is preserved on the surface after repeated washing of the latter with hot water. The concentration of chlorides at the surface of the metal after treatment with ODA is lower than before the treatment. __________ Translated from élektricheskie Stantsii, No. 11, November 2005, pp. 15–18.     

The effect of the current of the melting ice cover in the lightning-protection cable on the relay protection of an electric power line

The reasons for the excessive operation of the zero-sequence current protection of an overhead electric power line when there is melting ice cover on the lightning protection cable in circuits using the ground as the return conductor are explained. Translated from élektricheskie Stantsii, No. 12, December 2008, pp. 55–57.     

Slagging properties of coals and allowance for them in the analysis of the possibility of using out-of-design fuel

It is shown that out-of-design coal should be used only after computational analysis of slagging of the boiler. The use of ash fusibility as a criterion for the analysis should be avoided because this property does not reflect the slagging properties of coal to an acceptable degree. Parameters characterizing the properties more appropriately are presented. It is shown that slagging of an actual furnace depends on many factors and the condition that “the thermal stresses should be lower than the limiting value” is insufficient. An algorithm for the analysis is suggested on the basis of the slagging conditions arising upon transition from one kind of fuel to another with allowance for the actual slagging situation. __________ Translated from élektricheskie Stantsii, No. 3, March 2006, pp. 18–23.     

Complex efficiency indicator for separators in dust-preparation plants

A relationship for determination of the complex efficiency hcom of a separator, which graphically reflects the effectiveness of its operation from the standpoint of both output of prepared dust with an assigned amount retained on a sieve, and also with consideration of the extent to which fine fractions of final dust are excluded from the return, is presented on the basis of analysis of existing methods of determining classifier efficiency, experience with their use in power engineering, and the function of dust separators of coal-pulverizing mills in the production process of boiler plants at TPP. A procedure is proposed for determination of the value of hcom when an assigned amount of final dust is retained on a sieve during operation. The possibility of determining complex separator efficiency for mills with a built-in separator is analyzed. __________ Translated from élektricheskie Stantsii, No. 6, July 2007, pp. 6–10.     

Deoxygenation of chemically purified water at thermal power plants

Results are reported from experimental studies of the removal of dissolved oxygen from chemically purified water by catalytic hydrogenation on a palladium catalyst. Translated from élektricheskie Stantsii, December 2008, No. 12, pp. 42–45.     

Reliability of 330- and 500-kV Transmission Lines of the United Power System of Northern Caucasia

The necessity for employing nonparametric methods for evaluating statistical data on failures of transmission lines is substantiated. A method for evaluating the reliability of transmission lines based of the life characteristic of the object is suggested. The reliability of 330- and 500-kV transmission lines of Northern Caucasia is evaluated with the help of the methods suggested. __________ Translated from Elektricheskie Stantsii, No. 7, July 2005, pp. 58 – 64.     

Use of hydraulicking for clearing small rivers

Conclusions  

Analysis of Cyclic Load Capability of Boilers According to Conditions of Slag-Tap Removal

Original software that makes it possible to predict the viscosity of coal slag from data on its chemical composition as applied to results of domestic measurements is presented. The predictions are more accurate than those ensured by known domestic and foreign methods. The reliability of results is increased without changing the computational procedure by widening and amending the databank. A refined algorithm and software are suggested for computing the cyclic load capability of boilers from conditions of slag-tap removal. The method is based on integral computation of heat exchange in the combustion zone. The software has been tested for TP-87 and PK-40 boilers firing Kuznetskii coals of grades SS and T and for BKZ-320-140PT boiler firing Kansko-Achinskii coals. __________ Translated from Elektricheskie Stantsii, No. 6, June 2005, pp. 16 – 21.     

Effect of Operating Conditions of a T-250/300-240 Turbine on the Level of Wetness in the Stages of the Low-Pressure Cylinder

The operation of the low-pressure turbine part in variable condensing and extraction regimes is analyzed. The effect of steam parameters at the inlet to the low-pressure part (in the lower extraction chamber) and of operation of the regulating stage of the LPP on the level of wetness in the low-pressure stages is determined. It is shown that the moving blades of the last stages of cogeneration turbines operate under heavier erosion conditions than in condensing turbines. This is one of the main causes of their intense erosion wear. __________ Translated from Elektricheskie Stantsii, No. 6, June 2005, pp. 27 – 32.     

Damming the channel of the River Vakhsh in the section of the Sangtudinskaya GÉS-1 hydroelectric power plant

The damming of the channel of the River Vakhsh in the section of the Sangtudinskaya GéS-1 hydroelectric power plant using a three-embankment system, in which the central embankment is formed by means of a directed explosion from both banks, is described. Translated from élektricheskie Stantsii, No. 7, July 2008, pp. 43–46.     

Effect of fabrication procedure and metal quality of pipes formed from chromium-magnesium steel on their service properties

This paper examines the effect of fabrication procedure and metal quality on the service properties of pipes fashioned from chromium-magnesium steel DI59. The kinetics of the development of creep strain of the metal in the temperature region from 650 to 730°C is investigated. It is indicated that vigorous strain begins to develop after 90% of the expected life has been exhausted. It is established that in the steel under investigation, the content of σ-phase over the entire period corresponding to 30–90% exhaustion of expected life varies negligibly from 1.8 to 2.5%, and cannot be a criterion for estimation of exhaustion of the metal’s expected life. The investigations that we conducted on steel DI59 tubes fabricated in accordance with a new procedure indicated a significant increase in the long-term ductility of the steel, which dictates the high quality of the metal. __________ Translated from élektricheskie Stantsii, No. 6, June 2007, pp. 30–34.     

Design of twin-circuit towers for 500-kV OTL on inhabited localities

The experience of the “Otdelenie dal’nikh peredach” (ODP) Company on the design of multi-circuit overhead transmission lines (OTL), including towers for 500-kV lines, is described. It is suggested that specifications should be developed to supplement the “Rules for Construction of Electric Installations” as a first step for conversion of twin-circuit 500-kV OTL. __________ Translated from élektricheskie Stantsii, No. 11, November 2006, pp. 65–67.     

Improvements in the computation of balances and localization of commercial losses of electric energy in 0.38-kV networks

An example of four 0.38-kV overhead distribution lines fed from a 10/0.4-kV transformer substation of the Grodno Electrical Networks (Belarus’) and supplying electricity to a cottage area is used for analyzing energy balances and commercial losses in the networks. It is shown that the reliability of such analysis can be ensured by the use of modern software and electronic energy meters recording a retrospective of half-hourly intervals of active and reactive electric energy. __________ Translated from élektricheskie Stantsii, No. 9, September 2006, pp. 51–61.     

Technical solutions for a modernized TPE-216M boiler in a highly efficient unit

A design is presented for a modernized lignite-fired TPE-216M boiler for a highly efficient 225-MW power-generating unit, which can be installed at the Kharanorskaya state area power plant (Station No. 3). The boiler has a guaranteed gross efficiency of 92.5%, and satisfies modern ecological requirements: NO_x concentration of less then 300 mg/m³ in the flue gases, owing to the high gross efficiency of the unit, which is no less than 40%, NO_x emissions computed per 1 kW · h are reduced additionally by 10%, and the same applies to CO₂ emissions. The temperature of the steam is raised from 545 to 565°C. A low-pressure water economizer, which is included in the heat diagram of the unit, is installed to lower the temperature of the exiting gases. __________ Translated from élektricheskie Stantsii, No. 6, pp. 8–13, June, 2006.