Efficient ways for setting up the operation of nuclear power stations in power systems in the base load mode

The results obtained from studies of efficient ways and methods for organizing the operation of developing nuclear power stations in the base load mode are presented. We also show comparative efficiency of different scenarios for unloading condensing thermal power stations, cogeneration stations, combined-cycle power plants, nuclear power stations, and using off-peak electric energy for electricity-intensive loads: pumped-hydroelectric storage, electric-powered heat supply, and electrolysis of water for producing hydrogen and oxygen.     

Cogeneration steam turbines from Siemens: New solutions

The Enhanced Platform system intended for the design and manufacture of Siemens AG turbines is presented. It combines organizational and production measures allowing the production of various types of steam-turbine units with a power of up to 250 MWel from standard components. The Enhanced Platform designs feature higher efficiency, improved reliability, better flexibility, longer overhaul intervals, and lower production costs. The design features of SST-700 and SST-900 steam turbines are outlined. The SST-700 turbine is used in backpressure steam-turbine units (STU) or as a high-pressure cylinder in a two-cylinder condensing turbine with steam reheat. The design of an SST-700 single-cylinder turbine with a casing without horizontal split featuring better flexibility of the turbine unit is presented. An SST-900 turbine can be used as a combined IP and LP cylinder (IPLPC) in steam-turbine or combined-cycle power units with steam reheat. The arrangements of a turbine unit based on a combination of SST-700 and SST-900 turbines or SST-500 and SST-800 turbines are presented. Examples of this combination include, respectively, PGU-410 combinedcycle units (CCU) with a condensing turbine and PGU-420 CCUs with a cogeneration turbine. The main equipment items of a PGU-410 CCU comprise an SGT5-4000F gas-turbine unit (GTU) and STU consisting of SST-700 and SST-900RH steam turbines. The steam-turbine section of a PGU-420 cogeneration power unit has a single-shaft turbine unit with two SST-800 turbines and one SST-500 turbine giving a power output of N _{el. STU} = 150 MW under condensing conditions.     

Expedient arrangement of newly constructed systems for centralized heat supply

It is shown that for newly constructed combined-cycle cogeneration plants and nuclear cogeneration plants, the optimum arrangement of the centralized heat supply system is the combination of a cogeneration plant and a district heat-supply station (a boiler house).     

Thermal tests of the 9FB gas turbine unit produced by general electric

In July 2011, a PGU-410 combined-cycle power plant was commissioned at the Srendeuralsk district power station owned by Enel OGK-5. The main equipment of this power plant includes an MS9001FB gas turbine unit (produced by GE Energy Power Plant Systems, the United States), a heat recovery boiler (produced by Nooter/Ericsen, the United States), and a >Skoda KT-140-13.3 two-cylinder condensing and cogeneration turbine with steam reheating. In 2011–2012, specialists of the All-Russia Thermal Engineering Institute carried out thermal tests of this power plant in a wide range of loads and under different external conditions. The results from thermal tests of the MS9001FB gas turbine unit are presented and analyzed. The actual indicators of the gas turbine unit and its elements are determined and their characteristics are constructed.     

Optimization of cogeneration thermal power units

We present a procedure for comparing the efficiencies of cogeneration thermal power units that takes variable conditions of their operation into account. A combined-cycle plant operating in accordance with the STIG cycle (i.e., with mixing of working fluids), a gas turbine unit equipped with a gas economizer, and a steam turbine unit equipped with a backpressure turbine are compared during their operation as part of a cogeneration station.     

Technical refitting of cogeneration stations on the basis of combined-cycle technologies with the use of a parallel scheme

Results from analyzing different versions of combined-cycle toppings that can be used for technically refitting the TETs-23 cogeneration station are presented. Changes in the operating conditions of the turbine and boiler are investigated, thermal schemes are developed, and questions concerning the placement of new equipment on the old site are considered. An approach to evaluating the effect from refitting the cogeneration station is proposed that uses parameters calculated per unit of the additional power obtained during the refitting.     

All-regime combined-cycle plant: Engineering solutions

The development of distributed power generation systems as a supplement to the centralized unified power grid increases the operational stability and efficiency of the entire power generation industry and improves the power supply to consumers. An all-regime cogeneration combined-cycle plant with a power of 20–25 mW (PGU-20/25T) and an electrical efficiency above 50% has been developed at the All-Russia Thermal Engineering Institute (ATEI) as a distributed power generation object. The PGU-20/25T two-circuit cogeneration plant provides a wide electrical and thermal power adjustment range and the absence of the mutual effect of electrical and thermal power output regimes at controlled frequency and power in a unified or isolated grid. The PGU-20/25T combined-cycle plant incorporates a gas-turbine unit (GTU) with a power of 16 MW, a heat recovery boiler (HRB) with two burners (before the boiler and the last heating stage), and a cogeneration steam turbine with a power of 6/9 MW. The PGU-20/25T plant has a maximum electrical power of 22 MW and an efficiency of 50.8% in the heat recovery regime and a maximum thermal power output of 16.3 MW (14 Gcal/h) in the cogeneration regime. The use of burners can increase the electrical power to 25 MW in the steam condensation regime at an efficiency of 49% and the maximum thermal power output to 29.5 MW (25.4 Gcal/h). When the steam turbine is shut down, the thermal power output can grow to 32.6 MW (28 Gcal/h). The innovative equipment, which was specially developed for PGU-20/25T, improves the reliability of this plant and simplifies its operation. Among this equipment are microflame burners in the heat recovery boiler, a vacuum system based on liquid-ring pumps, and a vacuum deaerator. To enable the application of PGU-20/25T in water-stressed regions, an air condenser preventing the heat-transfer tubes from the risk of covering with ice during operation in frost air has been developed. The vacuum system eliminates the need for an extraneous source of steam for the startup of the PGU-20/25T plant. The vacuum deaerator provides prestartup deaeration and the filling of the entire condensate feed pipeline with deaerated water and also enables the maintenance of the water temperature before the boiler at a level of no lower than 60°C and the oxygen content at a level of no higher than 10 μg/L during operation under load. The microflame burners in the heat recovery boiler enable the independent adjustment of the electrical power and the thermal power output from the PGU-20/25T plant. All the innovative equipment has been tested on experimental prototypes.     

Qualitative and Quantitative Analysis of Organic Impurities in Feedwater of a Heat-Recovery Steam Generator

In recent years, combined-cycle units with heat-recovery steam generators have been constructed and commissioned extensively in the European part of Russia. By the example of the Kazan Cogeneration Power Station no. 3 (TETs-3), an affiliate of JSC TGK-16, the specific problems for most power stations with combined-cycle power units that stem from an elevated content of organic impurities in the feedwater of the heat-recovery steam generator (HRSG) are examined. The HRSG is fed with highly demineralized water in which the content of organic carbon is also standardized. It is assumed that the demineralized water coming from the chemical water treatment department of TETs-3 will be used. Natural water from the Volga River is treated to produce demineralized water. The results of a preliminary analysis of the feedwater demonstrate that certain quality indices, principally, the total organic carbon, are above the standard values. Hence, a comprehensive investigation of the feedwater for organic impurities was performed, which included determination of their structure using IR and UV spectroscopy techniques, potentiometric measurements, and element analysis; determination of physical and chemical properties of organic impurities; and prediction of their behavior in the HRSG. The estimation of the total organic carbon revealed that it exceeded the standard values in all sources of water comprising the feedwater for the HRSG. The extracted impurities were humic substances, namely, a mixture of humic and fulvic acids in a 20 : 80 ratio, respectively. In addition, an analysis was performed of water samples taken at all intermediate stages of water treatment to study the behavior of organic substances in different water treatment processes. An analysis of removal of the humus substances in sections of the water treatment plant yielded the concentration of organic substances on the HRSG condensate. This was from 100 to 150 μg/dm³. Organic impurities in boiler water can induce internal corrosion and deposits containing products of their degradation.     

The effectiveness of using advanced sources of energy operating on fossil and nuclear fuel for combined generation of electricity and heat

Possible technical solutions for natural gas-fired combined-cycle cogeneration stations, coal-fired combined-cycle cogeneration stations, and nuclear cogeneration stations are considered, and the comparative effectiveness of their use in different regions is evaluated for the medium- and long-term future.     

燃气蒸汽联合循环余热锅炉动态特性研究综述

燃气蒸汽联合循环余热锅炉是整个联合循环的重要组成部分之一,余热锅炉动态特性研究对整个燃气蒸汽联合循环具有重要作用。通过分析余热锅炉的热力特点,提出了燃气蒸汽联合循环余热锅炉动态特性研究的意义。然后,根据国内外的相关研究成果,从物理模型、数学模型和仿真方法三方面进行了分类和探讨。最后,对余热锅炉动态特性的研究发展提出建议和展望。     

Construction of power-generating gas turbine units with the use of efficient thermal schemes

The design features of GTE-30 and GTE-50 power-generating gas turbines, the basic thermal circuit of a PGU-90 (150) combined-cycle plant, and a layout solution for a cogeneration station built around a gas-turbine unit are considered.     

热电联产项目中机组的选型及参数确定方法

热电联产的原则是“以热定电”。文章介绍了热电联产的优势,对热电联产项目中的机组的选型提出了建议,给出了在热电项目立项准备阶段对热负荷、机组参数,热电厂总热指标和分项热指标的计算方法。     

联合循环热电联产机组参数优化及变工况性能分析

联合循环热电联产机组热效率高、污染小,具有广阔的应用前景。研究了联合循环热电联产机组效率的计算方法,并基于三菱MHPS 501GAC机组建立了热平衡模型,分析对比了不同蒸汽参数下联合循环热电联产机组的发电功率、机组热效率等性能指标。同时研究了机组在不同环境温度、大气压力、相对湿度、供热量等变工况状态下的性能。     

A comparative analysis of the economic effect from using cogeneration gas-turbine units and combined-cycle plants in a power system

The net cost of heat production at cogeneration stations equipped with gas turbine units, steam turbine units, and combined-cycle plants is analyzed by way of comparison. It is shown that the minimal net cost will be achieved in the case of using certain types of power installations depending on the network tariff for electric energy.     

Mastering the pilot domestic binary combined-cycle plants

Results are presented from mastering the pilot binary combined-cycle plants of Type PGU-450T (installed at the Severo-Zapadnaya TETs cogeneration station) and Type PGU-39 (installed at the Sochi thermal power station), both currently in commercial operation.     

Development and implementation of monitoring for the reactor core of unit No. 5 of the Novovoronezh nuclear plant by local parameters

In the course of upgrading the unit no. 5 reactor core of the Novovoronezh nuclear power plant, operational limits by local parameters, which limit the admissible linear power density and the relative power of fuel elements, were established. Due to applying modern computer technologies in systems of the in-core monitoring, the calculation of power density for all fuel elements in the real-time mode is implemented. To monitor the power density of fuel elements, the algorithm for determining the limiting linear power density is developed depending on the reactor core height and on the average nuclear fuel burnup. The admissible relative power of fuel elements is determined. In the course of the performed work, the excessive conservative limitations on nonuniformity of the reactor power density are excluded. The monitoring of power density by local parameters instead of indirect K _q (fuel-assembly relative power) and K _v (relative power of the fuel assembly section) made it possible to increase the fuel efficiency and to improve the economic parameters of fuel cycles of the unit no. 5 reactor core of the Novovoronezh nuclear power plant.     

小火电机组供热改造案例分析

热电联产是国家大力发展的节能技术。如何利用小火电发展热电联产是改造小火电机组的当务之急。本文以马鞍山发电厂小火电机组供热改造工程为例 ,通过供热经济性分析、财务评价经济指标分析 ,以及环境保护综合评价分析等 ,较全面地论述了“发展热电联产 ,改造小火电”的可行性     

新型带吸收式热泵热电联产机组的技术经济分析

针对带吸收式热泵回收利用冷端潜热用于供热的新型热电联产机组,以某电厂300MW供热机组为对象,利用Aspen软件建立相关数学模型,在保证机组设计最大供热要求不变的前提下,分析机组的热经济性及投资收益,结果表明,新型带吸收式热泵热电联产机组的煤耗下降15.8g/kWh,增加发电18.01MW,而投资回收期少于4a;在最大抽汽工况下,分析将排挤抽汽用于增加区域供热的热经济性及投资收益,结果表明,新型机组煤耗下降63.9g/kWh,增加供热105.28MW,而投资回收期少于3a,是值得推广应用的新型技术。     

The comparative effectiveness of serving peak loads in the variants of providing nuclear power plants with a base load

The present paper reports the results of an investigation into the effectiveness of serving peak loads in the variants of providing nuclear power plants with a base load through unloading condensing power plants, combined heat and power (CHP) plants, combined-cycle thermal power plants during night-time off-peak hours, the use of the off-peak electric power for power and heat supply, and water electrolysis with the use of hydrogen and oxygen for production of the peak electric power, as compared with the variant of the development of pumped storage hydropower plants.     

The heat-recovery power unit of a gas-piston mini cogeneration station

The specific features of the thermal operating conditions of the internal combustion engine and the design circuits of a mini cogeneration station’s heat-recovery unit are considered. The basic scheme of the heat-recovery unit’s thermal parameters automatic control system is proposed, the use of which makes it possible to maintain the design temperatures of coolants and heating agents (cooling liquid and oil, combustion products, and heat network water) during variations of the electrical and heat loads of consumers. The results from rig tests of the 450-kW(t) heat-recovery unit for a mini cogeneration station equipped with a YaMZ-8401 gaspiston engine are presented.