Papers selected for Conference Session titled : Power Plants life cycle extension, new clean coal technologies | Produženja radnog veka elektrana i novih ekološki čistih tehnologija
Goce Vasilevski - Rudarski Institut Skopje BJR Macedonia , Đorđe Kačurkov - Rudarski Institut Skopje BJR Macedonia , Dimitar Hadžimišev - Rudarski Institut Skopje BJR Macedonia
Abstract text
Production and usage of thermal and electrical energy, in conjuction with growing prices of basic energents leads to numerous economical problems even to the large energy consumers. Some problems as consumption of predefined energy (electrical energy or thermal energy as hot water or steam) in time and space domain can be solved through the usage of cogeneration units which can be used in Republic of Macedonia as it is shown.
In this period two cogeneration plants are prepared to start-up, wich are private investment and are located in Skopje. Technical and investment analysis for both plants are presented.
Greg Toomey, Senior Consultant - Energy and Vladimir Koković, Service engineer - SKF Condition Monitoring Center (San Diego) and SKF Commerce d.o.o. (Belgrade)
Abstract text
Many companies have performed Maintenance Strategy Reviews (MSR) using various methods, including Reliability-Centered Maintenance (RCM). Some have been successful, but many have not. Examining the reasons for these "failures" covers many areas, including work culture, organization limitations and technology deficiencies. This paper discusses the importance of going beyond a maintenance strategy study to achieve sustained success. It also discusses the need to formalize a continuous improvement process to ensure the appropriate maintenance is performed throughout the asset and facility life cycle.
In general, MSR projects generate task recommendations or changes to time-based activities (managed by Enterprise Asset Management (EAM)/Computerized Maintenance Management Systems (CMMS)), predictive and condition monitoring activities and operator inspection and data collection routines. Other activities are also discussed, such as potential design changes, material condition issues, etc. Once these MSR changes are identified, the effort to make updates in the various programs and processes is needed and should be an integral part of any project. Additionally, examining "infrastructure" and organizational needs for implementing the intent of the changes and to support continuous improvement processes needs to be reviewed and potentially changed.
Several case studies from application at power plants will be presented that illustrate the successes and failures of an MSR project. These studies will show how the project influenced the "infrastructure" used for the implementation, and other requirements for managing preventive and corrective work orders.
Ene BARBU - INCDT COMOTI, Iuliu Maniu 220D, Bucharest, 061126, ROMANIA , Gheorghe FETEA - INCDT COMOTI, Iuliu Maniu 220D, Bucharest, 061126, ROMANIA , Silviu IONESCU - INCDT COMOTI, Iuliu Maniu 220D, Bucharest, 061126, ROMANIA , Adina IONESCU - INCDT COMOTI, Iuliu Maniu 220D, Bucharest, 061126, ROMANIA , Mihaiella CRETU - INCDT COMOTI, Iuliu Maniu 220D, Bucharest, 061126, ROMANIA , Luminita HOSSU - INCDT COMOTI, Iuliu Maniu 220D, Bucharest, 061126, ROMANIA , Constantin VILCU - INCDT COMOTI, Iuliu Maniu 220D, Bucharest, 061126, ROMANIA , Cleopatra CUCIUMITA - INCDT COMOTI, Iuliu Maniu 220D, Bucharest, 061126, ROMANIA
Abstract text
The afterburning installation allows the increase in the cogenerative group’s flexibility according to the requirements of the technologic process and increases the steam quantity delivered by the heat recovery steam generator. The requirements concerning the development of high performance equipments with low environment impact and high flexibility have increased lately. Therefore a complex analysis is needed for obtaining the necessary data for designing the afterburning installation. The CFD numerical analysis of the burner in the afterburning installation of 2xST 18 - Suplacu de Barcau power plant showed that the air distribution in the burner can be improved. Researches were carried out on 2xST 18 cogeneration power plant after mounting the concentrator, regarding the processes in the afterburning facility at different regimes, in terms of emissions, noise, outer surface temperature profile and energy quality. The measurements in industrial conditions were performed in several stages on the two groups of the plant, before applying the global optimization solutions, in order to avoid the technological process disruptions. The noise map was realized based on the measurements made with two measurement chains using B&K 2250, respectively 01dBMetravib SOLO sound level meters. Air quality measurements were performed with the COMOTI air quality mobile laboratory. For measuring the emissions a Horiba PG 250 analyzer was used with the sampler probe installed at the heat recovery steam generator stack in 2xST 18 – Suplacu de Barcau power plant. The exterior surface temperature profile was measured using a Fluke infrared camera, type Ti45FT. For a detailed research of the processes and for removing disturbing factors in the plant, there were necessary some validations on the test bench for the data obtained from 2xST 18 - Suplacu de Barcau cogenerative power plant and the numerical results in CFD environment. For this purpose two type gas fuelled burners were built, the INCDT APC 1MGN-UPB burner and the INCDT APC 1-3MGN burner. The INCDT APC 1MGN-UPB burner allows testing only one ST 18 burning module (or splay) but it can be adapted to other burning modules geometries framed in the ST 18 range. Experimentations of the INCDT APC 1MGN-UPB burner with the ST 18 burner module (or splay) were made on the University Politehnica of Bucharest (UPB) test bench, at the Classic and Nuclear Thermo-mechanic Equipment Chair. Experiments regarding the emissions, noise and surface temperature profile obtained by infrared analysis were performed at different fuel gas flows. The paper presents experiments performed on the UPB stand for INCD APC 1MGN-UPB burner combustion module ST 18 (or splay) starting to the data obtained in 2xST 18 cogenerative power plant.
Craig Buckley - Clyde Bergemann Materials Handling Ltd
Abstract text
The continuing demand for cleaner coal-fired boiler plants around the globe is adding pressure on power operators to ensure that best practices and technologies are in place to support this. In addition, high plant efficiency and availability is required in order to keep up with the growing demand for energy worldwide.
This paper presents the benefits of replacing a Lean-Phase conveying systems with a cost-effective Dense-Phase solution at a 4 x 660 MW coal-fired power plant. The solution, designed to increase ash conveying capacity, improve overall availability of the plant and reduce water consumption, uses a combination of dry and wet Dense-Phase technology to cater for the ash handling requirements of the existing fabric filters installed on the plant. Furthermore, coarse and fine ash can be separated in the process where the fine ash is used for further utilisation in the concrete and cement industries and the mixed un-saleable ash is diverted to the ash pond 3km away using high pressure piston diaphragm pumps with low volumes of water to transport over long distances.
Combining these technology's implements a plant with a high level of reliability and flexibility allowing the station to meet their initial and long term energy and environmental objectives.
Daniel Bartels - Clyde Bergemann GmbH, 46485 Wesel, Germany , Matthias Schumacher - Clyde Bergemann GmbH, 46485 Wesel, Germany , Manfred Frach - Clyde Bergemann GmbH, 46485 Wesel, Germany , Christian Mueller - Clyde Bergemann GmbH, 46485 Wesel, Germany
Abstract text
Ash-related operational challenges caused by slagging and fouling are currently the main reason for reduced boiler efficiency and unscheduled shutdowns. As deposit formation is influenced by numerous and continuously varying process parameters, these parameters need to be considered during boiler cleaning to avoid inappropriate cleaning actions. To utilize boiler cleaning to guarantee steady boiler operation, it needs to be controlled by the following aspects:
- WHERE exactly is cleaning required?
- HOW intensive does the cleaning need to be?
- WHEN is the best point in time to execute cleaning?
The use of these aspects guarantees that boiler cleaning is executed demand-driven and no longer subject to manual or time-triggered control. Accomplished with plant specific process data, boiler cleaning can be flexibly adjusted to fuel and boiler specific conditions.
This kind of intelligent boiler cleaning has been applied to a coal-fired 350 MW boiler. This reference shows how an existing boiler cleaning system can be upgraded to a demand-driven operation by means of direct measurements combined with dynamic software algorithms.
dr Jovan Janjić, dipl. maš. inž. - Department for Strategy and Investment, Public Enterprise ”Electric power industry of Serbia” , dr Slobodan Đekić, dipl. maš. inž. - Department for Strategy and Investment, Public Enterprise ”Electric power industry of Serbia”
Abstract text
World electricity consumprion intensivly increases. Besides of all efforts towards energy saving, such inevitable demand increses need for installation of new electricity generating capacities and searching for new energy sources. Iron industry belongs to the goroup of the most extensive and largest energy and fluids consumers. Iron industry at Smederevo is very large consumer of natural gas and blast furnace gas. Pressure of natural gas reduces at reduction and measuring station of „Energogas“ from 40 to 6 bar. The bast furnace gas reduces from 2,5 to 1,07 bar at the production area. Within this paper recommands use of expansion gas turbines for the pressure reduction of bast furnace gas. Applying this idea, a load of 5- 6 MW from the blust furnace gas pressure reduction could be achived.
MOGUĆNOST DOBIJANJA ELEKTRIČNE ENERGIJE IZ ENERGIJE PRITISKA VISOKOPEĆNOG GASA U ŽELEZARI SMEDEREVO (USS)
Potrošnja električne energije u svetu intenzivno raste. I pored svih napora na uštedi energije, to nameće potrebu za izgradnjom novih energetskih postrojenja i iznalaženja novih izvora energije. Crna metalurgija spada u red najintenzivnijih i najvećih potrošača energije i fluida. U železari Smederevo posebno je velika potrošnja prirodnog i visokopećnog gasa. Pritisak prirodnog gasa se sni#ava u merno- regulacionoj stanici „Energogas“-a sa 40 na 6 bara, dok se pritisak visokopećni gas sni#ava u postrojenju Visoke peći sa 2,5 na 1,07 bara. U radu se predlaže, s’ obzirom na veliku potrošnju visokopećnog gasa, da se redukcija pritiska obavlja preko ekspanzione turbine. Na taj način bi se mogla ostvariti snaga od 5-6 MW.
Zdravko N. Milovanović - Faculty of Mechanical Engineering, University in Banja Luka, S. Stepanovića 71, 78000 Banja Luka , Vinko Babić - Faculty of Mechanical Engineering, University in Banja Luka, S. Stepanovića 71, 78000 Banja Luka
Abstract text
Exploitation and maintenance of steam turbines, as a complex technical systems from the aspect of the amount of necessary investments during their lifetime is directly in the function of the method for definition and accomplishment of wanted efficiency (reliability, readiness and convenient maintenance), both on the level of their design and during their exploitation. Repair activities performed as a part of steam turbine system are based on manufacturer’s instructions, with application of corresponding modern diagnostics and control equipment, as well as specially trained personnel for implementation of complex operations during assembly and breakup of certain turbine blocks and their parts. The process of revitalisation means extension of lifetime for exploitation which is often followed by modernisation and reconstruction of technical system, with improvement of their ecologic acceptance. This systematic and comprehensive procedure with complex technical systems, such as Thermal Power Plant system, presents unavoidable and logic process during period of the object utilisation. Every takeover of both newly built and revitalised turbine plants requires application of certain testing, in order to determine real value of unit parameters and achieved improvements in the case of revitalisation and modernisation of steam turbine and ancillary equipment. This way, indirectly, concludes on quality of executed agreed work from the aspect of achieving needed working performances of steam turbine. Occasionally, standard normative measurements are performed and these present integral part for surveying of steam turbine in the plant, in order to determine the value of efficiency level (initial data for normative exploitation).
PARNE TURBINE I MOGUĆNOSTI PRODUŽENJA RADNOG VIJEKA
Eksploatacija i održavanje parnih turbina, kao složenih tehničkih sistema sa aspekta visine neophodnih ulaganja u toku njihovog vijeka trajanja, direktno je u funkciji načina definisanja i ostvarivanja željene efektivnosti (pouzdanosti, gotovosti i pogodnosti održavanja), kako na nivou njihovog projektovanja tako i u toku same njihove eksploatacije. Remontne aktivnosti, koje se sprovode u okviru sistema parne turbine zasnivaju se na instrukcijama njihovog proizvođa, uz primjenu prateće savremene dijagnostičke i kontrolne opreme, kao i osoblja posebno obučenog za izvođenje složenih operacija prilikom demontaže i montaže pojedinih turbinskih sklopova i njihovih dijelova. Proces revitalizacije predstavlja produženje vijeka upotrebe koje uglavnom prati modernizaciju i rekonstrukciju tehničkog sistema, uz poboljšanje njegove ekološke prihvatljivosti. Ovakav sistemski i sveobuhvatni postupak kod složenih tehničkih sistema, kakvi su npr. sistemi termoelektrana, predstavlja nezaobilazan i logičan proces u vijeku upotrebe objekta. Svaka primopredaja kako novoizgrađenih tako i revitalizovanih turbinskih postrojenja zahtijeva sprovođenje određenih garantnih ispitivanja, s ciljem utvrđivanja stvarnih vrijednosti pogonskih parametara i dobijenih poboljšanja u slučaju revitalizacije i modernizacije parne turbine i njene prateće opreme. Na ovaj način se indirektno dolazi do zaključka o kvalitetu izvršenih radova ugovorenog posla sa aspekta dostizanja potrebnih radnih performansi parne turbine. Takođe, povremeno se obavljaju standardom propisana normativna mjerenja, koja predstavljaju sastavni dio nadzora nad parnom turbinom u pogonu, s ciljem utvrđivanja vrijednosti njihovog stepena korisnosti (polazni podatak za normative u eksploataciji).
Dane Džepčeski, Dušan Arnautović, Jelena Pavlović, Slobodan Bogdanović - Electrical Engeneering Institute Nikola Tesla, Belgrade, SERBIA
Abstract text
In this paper electrical part of the novel turbine governing system for the hydraulic turbines is shown. Presented system is designed for station service power generator in HPP „Bistrica“. However, the concept of the system is of general purpose. There is ability to upgrade, both hardware and software, as to functionality of the system. Considerable flexibility of the system structure enables its adaptation to any type of hydraulic turbine, either that the turbine flow is controlled by one or by number of electrohydraulic converters. Special attention is given to the new speed and active power digital governor. Functions and features that a modern turbine regulation system should have are listed and systematized. Implementation of these functions is described and features of the particular turbine governor are shown. Hardware platform and associated software required for the execution of control and regulation functions are presented, as well as realisation of the interface to the superior control system and to the operator. Test setup with the simulator of the turbine governor environment is described. Processes in the turbine instalment are modeled in the simulator. Model of the hydrosystem, intake and penstock, hydraulic turbine, hydraulic servomotor, model of the electric generator and its load are included in the simulator. Regulation loop that consists of the real digital turbine governor based on programmable logic controller and of simulator that is based on digital computer is shown. Analog and digital signals interchange between the governor and the simulator is performed in the real-time, wherewith testing of the regulation function and its adaptation and parametrization in the real-time is enabled. Test results of the novel digital turbine governor on the simulator are shown. Also the comparison of these results with the results of field test of the existing hydro-mechanical turbine governor in HPP „Bistrica“ is presented. НОВИ ДИГИТАЛНИ РЕГУЛАТОР ХИДРАУЛИЧНЕ ТУРБИНЕ (Преференцијална тема 2 и 4) Садржај: У раду је приказан нови електрични део система за турбинску регулацију хидроагрегата. Приказани електрични део система за турбинску регулацију намењен је агрегату сопствене потрошње у ХЕ „Бистрица“. Међутим, концепција система је опште намене. Постоји могућност његове надоградње и проширења како у хардверском тако и у програмском, односно функционалном смислу. Флексибилност структуре омогућава њено прилагођење свакој врсти хидрауличне турбине, било да је проток флуида кроз турбину регулисан радом једног или више електрохидрауличких извршних органа. Посебна пажња посвећена је новом дигиталном регулатору брзине и активне снаге агрегата. Функције и особине које један савремени систем за турбинску регулацију треба да поседује наведене и систематизоване су у раду. Описана је реализација ових функција и приказане су карактеристике турбинског регулатора. Приказана је хардверска платформа регулатора као и придружена програмска подршка, потребна за извршавање управљачких и регулационих функција, као и за реализацију везе са надређеним системом управљања и везе са руковаоцем. У раду је описано испитно поље са симулатором околине турбинског регулатора. У симулатору околине турбинског регулатора моделирани су процеси у турбинском постројењу. Симулатор садржи модел хидросистема, турбине, извршног органа за регулацију турбине, генератора и оптерећења генератора. Приказана је остварена веза између реалног турбинског
L. Joleska Bureska*, R. V. Filkoski**, I. J. Petrovski** - *REK ”Bitola”, **Univ. "Ss Cyril and Methodius", Faculty of Mechanical Eng., Skopje, R. Macedonia
Abstract text
Modelling of fossil fuel utility boilers has reached a remarkable development, particularly through the application of CFD technology and other advanced mathematical methods. With the tendency for improvement of the energy efficiency, nowadays, much thought is given to the increasing the overall efficiency of the energy facilities and to reducing the amount of various harmful materials emitted into the atmosphere when burning fossil fuels. One of the ways to improve the overall operational efficiency of the pulverised coal-fired boilers is reduction of the heat loss due to inefficient combustion, which is closely related with the reduction of the emission of pollutants. The both tasks, energy efficiency increase and reduction of air pollution, can be obtained with appropriate redistribution of the air inlet, including implementation of over-fire-air system (OFA) and lower air-blow ports.
The paper considers the effect of air redistribution on the flow field, combustion efficiency and temperature profiles, with implementation of lower air ports in a boiler furnace. The overall framework and the initial computational fluid dynamics (CFD) analysis of the aerodynamic behaviour of the gas-solids mixture, combustion efficiency, temperature profiles and gas concentrations is described. The numerical results obtained with CFD modelling technique are compared with a measurements test matrix of various operating conditions. The main parameters that were changed are air quantity distribution, boiler load and burners load. Although this is just an initial research phase, comparisons of numerically obtained and measured temperature profiles are encouraging. The data regarding the near-burner regions showed evidence of intensified swirl and increased combustion efficiency, as under-fire air quantity was increased.
Ramin Haghighi Khoshkhoo - Power and Water University of technology , Mohammad tanassan - Monenco Iran Consulting Engineers Co
Abstract text
Repowering fossil fuel power plants has been considered to increase power output and reduce emissions at low cost and short outage periods. Besat is one of the oldest power plants in Iran which is located in south of Tehran. Besat net power output has been decreased about 19 percent, and its repowering is inevitable. As one of the most important parameters of repowering, size and type of the gas turbine is considered and Feedwater repowering schemes have been analyzed using thermodynamic simulations. The objective is evaluating the efficiency increase of the overall system, and also total power output. It seems that selection of gas turbine is directly dependent on the purpose of repowering. Results highlight the repowering as a suitable technology to reduce heat rate and increase total power output. It could help to increase power plant ability, in a short time and in a cost-effective manner.