Katarzyna OSZAŃCA, Janusz POSPOLITA, Ryszard PARYS
Evaluation of roller pan mill exploitation parameters influence on consumption of energy used for coal dust preparation
Energetyka 2008, nr 4, s. 248
Presented is the influence of various parameters characterizing construction and operation of mill unit on specific energy consumption needed for milling and ventillation as well as on quality of dust received. The analyses concern the RP1043x mill. Investigations show the dust quality deterioration after adding of biomass to the coal processed, particularly when the amount of added biomass is on the level of 8-10%. Henryk OTWINOWSKI, Dariusz URBANIAK, Evgenij V. BAROČKIN, Vladimir P. ŽUKOV
Mathematical modelling of multistage heat exchangers
Energetyka 2008, nr 4, s. 261
Presented is methodology for computation of multistage heat exchangers. Defined are principles of linear equations system construction in a matrix form. Solution of the system of equations allows determination of temperature at all points of a multistage heat exchanger and enables analyzing thermal and economical efficiency of the unit.
Soil contamination with oil-derived substances occurring in power engineering and their bioremediation methods
Energetyka 2008, nr 4, s. 267
Mentioned is the problem of ecological hazard resulting from soil contamination with oil-derived substances in power plants and CHPs. Special attention is paid to the problem of contaminated grounds recultivation necessity. Presented are selected methods of oil-derived substances biological degradation. Discussed are factors having influence on the course of bioremediation process.
Reactance insulators as measuring signal source for Power System Protection devices
Energetyka 2008, nr 4, s. 273
Presented are possibilities to make use of measuring signal received from reactance insulators in power system protection devices. Discussed are some exemplary devices serving this purpose constructed and produced by "Energotest-Energopomiar" Sp. z o.o.
Franciszek SPYRA, Marian URBAŃCZYK
Selection of return conductor cross-section dimensions in power cables
Energetyka 2008, nr 4, s. 276
Presented is analysis of return conductor adiabatic heating problem caused by short-circuit current. Given are dependances making it possible to calculate temperature of return conductor during short-circuit fault, short-circuit current capability for the given condustor cross-section dimensions and fault clearance time as well as the needed conductor cross-section for the given fault current and fault clearance time. Results are illustrated with examples taken from engineering practice.
Material diagnosis on-line of power station thermo-mechanical installations
Energetyka 2008, nr 4, s. 279
In many, from the point of view of knowledge and technology, technically advanced branches on-line diagnosis becomes a fact. Also in power industry new power blocks are now offered with the possibility to diagnose selected elements, construction joints and even whole installations in this way. Diagnosis on-line brings many advantages in the range of power installations maintenance optimization in such fields like technology, economy and organization. Diagnosis realized in real time is usually associated with diagnosis of turbo-machines or thermodynamic diagnosis. Material diagnosis can also be realized continously. The easiest way of accomplishing such a task is the application in a newly commissioned installation. For older type power blocks many limitations concerning using of this method must be taken into account. But the main barrier is not so much the technical equipment of power installations as an access to all necessary information relating to the condition of installation as well as maintenance policy a power plant.
Jerzy DOBOSIEWCZ, Ewa ZBROIŃSKA-SZCZECHURA
Evaluation of service life of steam boiler superheater headers working in creeping conditions
Energetyka 2008, nr 4, s. 283
Calculated values of exhaust factor and damage occurrence risk in time between overhauls are not very accurate and their scatter band width is about ±20%. It results from material data which can be found in adequate standards and used for calculations of probabilistic methods. Taking all this into consideration the inspection of a plant condition with the use of diagnostic testing is advisable. That is why tested elements should be subject to inspections as well as to destructive and non-destructive tests.
Tomasz SADOWSKI, Grzegorz ŚWIDERSKI, Włodzimierz LEWANDOWSKI
Utilization of renewable and non-renewable energy sources in Poland and in the UE countries
Energetyka 2008, nr 4, s. 289
Specified are conventional (non-renewable) and alternative (renewable) energy sources utilized in the world, in Europe and in Poland. Described are methods of obtaining energy from non-renewable sources and their influence on the environment. Characterized are renevable energy sources. Presented is percentage share of wind and hydro power industries in electric energy production in Poland and in the UE countries.wastes.