Jacek MALKO
Our uncertain energy future
Described are elements which all together create a feeling of big uncertainty if we talk about the global energy future. Many reports, expert opinions and strategic studies indicate that the key role will be played by energy supply systems. The abundance of energy allows application of energy-consuming technologies for desalination, water treatment and transportation technologies and this, in turn, ensures food production in quantities adequate to meet the needs. The attention is called to the fact that GHG emission limitation plans declared in public are not adequate to climatic challenges which the energy sector will face in its pursuit of ensuring an access to energy services for the whole mankind. Despite considerable efforts being undertaken by international institutions and state governments with the aim to stimulate energy effectiveness development, the obtained results are rather poor. Energy market transformation with the aim to increase the effectiveness, needs the application of special regulation policies and financial incentives. There are more than only one model of such activities, especially if it concerns the demand side management (DSM). Institutional frames - strong infrastructure able to absorb implementations and effective management mechanisms able to carry out the indispensable reforms - must be strengthened for better regulation policy efficiency especially in the range of developing economics.
Keywords: global energy needs, energy system evolution, conditioning of structural changes
Roman KOŁODZIEJ
Energy Performance Certificate system
Energy Performance Certificate System (white certificates) introduced by the Energy Efficiency Act of 15 April 2011 not only imposes on enterprises several additional obligations but also creates a chance to acquire financial means resulting from realisation of projects serving the energy efficiency improvement. The article enables closer approach to main assumptions and to the way the system works, taking into consideration the conditionings referring to the first step in the tender process concerning the selection of projects serving the energy efficiency improvement for which one can get the “white cerfiticates”. The tender was launched by the President of the Energy Regulatory Office on 31 December 2012. We must wait for the effects of system functioning until the tender is adjudicated – the tender closing date was 30 January 2013.
Keywords: Energy Performance Certiciate System – white certificates, assumptions and the way the system works
Grzegorz WERNER, Eugeniusz GŁOWACKI
Investigation methods of mercury emission from energy sector. Influence of fuel variability on mercury emission and representability of measurement results
Mercury content in coal is the first thing determining the emission volume of this element during the combustion process. The type and construction of a boiler are also important as well as the progress and organization of the combustion process itself. Conventional flue gas treatment systems reduce to a high degree the emission of mercury by its separation from flue gases and then inserting it into the given process products. Variability of mercury content in coals and influence of combustion process on the emission result in fluctuations of mercury concentration and speciation in flue gases. In this connection, all manual methods giving the result which is a mean value for the sampling time do not meet all new demands being made on measurement laboratories. Effective are the systems for continuous measurement of mercury. Discussed are all the above mentioned problems and presented are some of object investigation examples.
Keywords: energy sector, mercury emission, fuel variability, object investigation
Kazimierz ZAMOROWSKI
Available denitrification technologies of flue gas coming from the domestic power industry boilers
Review is made of NOx emission reduction technologies according to their evolution in the domestic power industry. Beginning with the simplest and most often applied primary method technologies i.e. modification of combustion process in boilers by excess air curtailment in the combustion chamber or feeding the afterburning air with the use of overfire air nozzles, presented are also the remaining, more complex primary method technologies. Discussed are secondary method technologies like selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR). Described are their possible applications and estimated is their effectiveness.
Keywords: denitrification of boiler flue gases, technologies of NOx emission reduction
Artur JASIŃSKI
Phenomena influencing the failure frequency of the type WR 25 water-tube boilers piping system and methods of their reduction with the aim to increase availability and operational certainty
Destruction processes of a boiler heating surface piping system influence substantially the availability and operational certainty of water-tube boilers. Our knowledge about their further operational possibilities is conditioned by the awareness about the real technical condition of the equipment and the accurate identification of destruction processes. Especially, in the context of heating surfaces, the material diagnostics plays an important role because, as a rule, the failures of boilers pressure parts are the result of more than only one destruction process - that is why it is vital to elaborate the rules concerning evaluation of the scale and speed of destruction and damages. In the recent years “ENERGOPOMIAR” Sp. z o.o. has carried out many evaluations of water-tube boilers technical condition. During these works many incorrectnesses were found which are now described in this article. As the experience shows, the character of damages and the occurring destruction processes of boilers pressure elements change during the operation - that is why their correct identification for the needs of planned boiler overhauling is so important.
Keywords: piping system of the type WR 25 water-tube boiler, piping system failure frequency, boiler availability increase
Wiesław TOCZEK
Damping of a steam turbine self-excited vibrations with the use of four-key bearings
Discussed is the use of four key-bearings in steam turbines as the method to damp the turbine self-excited vibrations. The comparison of four-key bearing characteristics with the previously used ones shows achieving of significant improvement of dynamic properties. Application of four-key bearings enables reduction of vibrations caused by aerodynamic forces arising in over-shroud seals, changes the stability limits and makes possible the safe work in the range of rotor shifting. As a result of the four-key bearing application, the dynamic condition of a machine can be improved without opening it.
Keywrods: steam turbines, four-key bearings, vibration damping
Łukasz KUREK, Barbara ROJEK
Solutions in vertical and horizontal transportation of heavy equipment
Presented are methods applied by ZRE Katowice for horizontal transportation of heavy equipment. The applied by ZRE Katowice system of rigid steel bars allows hoisting the loads of up to 250 t. The hoisting constructions cooperate perfectly with the “push-pull” system which allows moving the loads of up to 400 t, after the adequate railway track underpinning has been made, but there are no contraindications to move or hoist loads of bigger weights.
Keywords: transportation of power machinery heavy elements, horizontal transport, steel bar transportation system
Jerzy SZKLARZ
ZRE Katowice SA experience in overhauls carried out by welding of steam turbine runners
Discussed is ZRE Katowice SA experience gained in the way of research, repairs and runners regeneration. Indicated is that runners overhaul is the last element which enables elongation of a turbine lifetime up to 350 000 hours and even more, with no need of main parts replacement. The remaining parts can undergo the revitalization process in which the primary structure and needed geometry are reconstructed. At the same time a modernization can be carried out in the way of changes in geometry and construction of rotors and deflectors enabling, for instance, application of modernized blades. The elaborated and implemented technology of runner regeneration (reconstruction of even all rotor disks) is a completion of all earlier steam turbine lifetime elongation technologies such as housing revitalization or rotor disks reconstruction. At present, ZRE Katowice SA is in a possession of all necessary tools and technologies to effectively interfere in all important turbine parts, elongating their lifetime - in accordance with the power industry requirements - for over 350 000 working hours.
Keywords: steam turbines, rotors regeneration and repairs, modernization of turbine runners
Adam DRAGON, Piotr MASTELA
Modernization of a power unit in TAURON Wytwarzanie – Elektrownia Jaworzno III – Elektrownia II
Presented is the range and progress of modernization process of the power unit turbine part with its systems and auxiliaries, as well as the works connected with adaptation of the existing foundation and a new power unit assembly in the so-called “Elektrownia II” in Elektrownia Jaworzno III. The aim of modernization was: adaptation of the existing systems to the new biomass boiler needs, maintaining of the power unit rated power i.e. of the turbine with a replaced generator on a level of at least 50 MW, elongation of a life-time of installations under operation for a period of at least 200 000 hours (25 years), ensuring high operational reliability of the turbine and its auxiliaries with the aim to generate and sell “green energy” and also enhancing working safety and service comfort.
Keywords: coal-fired power units, biomass combustion, adaptation of a coal-fired power unit to biomass combustion
Jarosław OSIAK, Adam KUPCZYK, Ewa GOLISZ
Weak competitiveness of Polish bioethanol producers
Attention is called to the fact that the key element of production and utilization of biofuels would be the environmental benefits, including the possibility of greenhouse gases emission reduction. Estimated is that 25% of global CO2 emission produced in connection with civilization development, comes from the road transportation sector. During combustion process of bioethanol or petrol in a combustion motor a certain amount of CO2 is released to the atmosphere. A thesis has been accepted that theoretically the biofuels are neutral as far as the carbon dioxide is concerned, because CO2 is absorbed during the growth of a plant used for bioethanol production. But the benefits from biofuels are not so obvious in the case of life-cycle analysis (LCA) during which not only combustion is investigated but also the production and biofeedstock processing into fuel. CO2 emission reduction amounts then to only about 18-25% for the 2-phase bioethanol production system (distillate production in a distillery, unwatering in some other plant) and 40% for one-phase system (bioethanol production in one plant). The European Commission supports the biofuels of second generation, produced from inedible plants and wastes. But there is still a lack of an economically effective technology of the second generation transportation biofuels production on a large scale, for instance from plants containing lignocellulose. It is expected that various forms of support for the first generation biofuels will end completely until the year 2020. Therefore, only the second generation biofuels production from waste feedstocks will be continued.
Keywords: biofuels, bioethanol, competitiveness of Polish producers