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1

Praca zasobnika ciepła z uwagi na systemy dostarczania i odbioru ciepła

Matysko Robert

Chłodnictwo i Klimatyzacja

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2023

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nr 10

42--48

PL

W artykule przedstawiono zagadnienia dotyczące pracy zasobnika ciepła w złożonym systemie grzewczym. Przeanalizowano dynamikę zasobnika ciepła, biorąc pod uwagę procesy wytwarzania ciepła w złożonej strukturze zasilania w ciepło. Jako systemy grzewcze doprowadzające ciepło do zasobnika ciepła przeanalizowano zintegrowany obieg ORC i pompę ciepła. Wykonano analizę CFD procesów konwekcyjnych zachodzących w zasobniku ciepła. Przedstawiono również badania eksperymentalne zasobnika ciepła podczas jego eksploatacji periodycznej oraz podczas procesu magazynowania ciepła.

2

Modeling, exergy analysis and optimization of cement plant industry

Abutorabi Hossein, Kianpour Ehsan

Journal of Mechanical and Energy Engineering

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2022

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Vol. 6, No 1

55--65

EN

This study investigates the recovery of wasted heat in the cement plant industries (Neka Cement Factory) in order to reduce the use of fossil fuels and greenhouse gas emissions. Cement is the most widely used man-made material. The global cement industry produces about 3.3 billion tons of cement annually. A lot of energy is needed to produce cement. About 200 kg of coal is used to produce each ton of cement. The cement industry also produces about five percent of the world's greenhouse gases. The method studied in this research is based on heat recovery from boilers installed at the outlet of a clinker cooler and a preheater in a cement factory. Due to the low temperature of the gases available, three different fluids, i.e. water, R134a and R245fa were considered as the operating fluids. Also, energy and exergy analyses are performed in a Rankin cycle and the selection of optimal parameters is considered by using genetic algorithm. The results of this study showed that water with optimized parameters leads to an increase in the production capacity from 5 to 9 MW. However, fluid R134a with optimized parameters leads to a 4% increase in exergy losses and it also increases the production capacity from 5 to 9 MW.

3

Influence of the temperature difference between the heat source and the evaporation temperature in ORC systems working with natural refrigerants

Rusowicz Artur, Grzebielec Andrzej, Łapka Piotr

Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

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2022

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Nr 1

46--57

EN

The use of waste heat in many branches of industry is limited due to temperature in the range of 30 to 100°C. One of the methods of using waste heat are devices that implement the Organic Rankine Cycle (ORC). In currently used ORC systems, the heat source temperature is at least 80oC, while the low temperature heat source (usually atmospheric air) has a temperature of 30oC. The work analyzes the influence of the organic fluids properties on the performance of the proposed installation driven by the waste heat and working based on the ORC. The basic operation parameters in nominal conditions were determined for three selected natural refrigerants R290, R600a, R717 and one synthetic R245fa. The condensing temperature 30oC were defined as a nominal value. The research results compare how the generated electric power will change depending on the temperature difference between the temperature of the heat source and the temperature of evaporation. It turns out that for a device with finite dimensions, the maximum power is obtained for a specific evaporation temperature. And this is not the highest temperature that can be achieved. The highest evaporation temperature allows for the highest efficiency of the system, but not the maximum of capacity.

4

Niekonwencjonalne metody odzysku ciepła w układach przemysłowych

Matysko Robert, Wiśniewska Weronika

Chłodnictwo i Klimatyzacja

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2022

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nr 1

40--45

PL

W artykule przedstawiono przegląd metod niekonwencjonalnych systemów odzysku ciepła. Opisano możliwości odzysku ciepła z wykorzystaniem układów absorpcyjnych, sprężarkowych oraz ORC. Przybliżono również klasyczne metody odzysku ciepła z procesu spalania. Zastosowanie metod konwencjonalnych oraz niekonwencjonalnych odzysku ciepła sprzyja poprawie efektywności energetycznej realizowanych procesów. Odzysk ciepła pozwala również zmniejszyć zużycie coraz droższych paliw kopalnych oraz redukuje negatywny wpływ na środowisko naturalne.

5

Working Fluid Selection for Simple and Recuperative Organic Rankine Cycle Operating Under Varying Conditions: A Comparative Analysis

Igbong Dodeye, Nyong Oku E., Enyia James, Agba Ambrose

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 4

202--221

EN

The selection of suitable working fluid for simple and recuperative organic Rankine cycle (ORC) operating under subcritical, superheated and supercritical conditions are investigated. 11 fluids with critical temperature above 1500C are considered as potential candidates. Performance screening parameters such as net power output, thermal efficiency, turbine sizing parameter (SP) and volumetric flow ratio (VFR), exegetic parameters like irreversibility rate, fuel depletion ratio, and improvement potential rate of exergy destruction were also evaluated. Results indicate that R600a, R236fa and R1233dz(E) demonstrated the best performance for subcritical, superheated and supercritical simple ORC, respectively. R236fa and R1233dz(E) proved more suitable for subcritical/superheated and supercritical recuperative cycles, respectively. The system exegetic efficiency is reveal to be significantly higher in subcritical/superheated (61-65%) cycles compared to the supercritical (35-45%) cycle, the evaporator seen as the main source of exergy destruction, accounting for 17-37% of inlet exergy destroyed and about 8-24% in the turbine.

6

Implementation of heat storage and network water cooler for improvement of energy and economic performance of municipal heating plant with biomass fired cogeneration module

Świerzewski Mateusz, Kalina Jacek

Journal of Power Technologies

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2019

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Vol. 99, nr 2

131--141

EN

Many fossil fuel fired municipal heating plants have been upgraded to cogeneration systems through installation of biomass fired cogeneration modules. This paper shows the effects of installing an Organic Rankine Cycle (ORC) technology based module in a plant with coal fired water boilers. Current problems related to operation of the integrated system are presented and discussed. Special attention is given to the volatility of the main operational parameters, which impacts the economic performance of the project. With a view to enhancing performance, new equipment such as heat storage and a district heating water cooler are proposed and examined. A mathematical simulation model and optimization algorithm for thermal energy storage capacity sizing were developed using the commercial software EBSILON® Professional. The model was calibrated and validated with real measurement data from the SCADA system of the plant. Results of simulations revealed potential annual financial benefits related to savings of chemical energy of fuels and selling excess electricity on the balancing market. The results of these simulations prove that proposed modifications of the technological system structure could be a good option for increasing investment profitability at the current level of fuel and energy prices.

7

Comparison of an impulse and a reaction turbine stage for an ORC power plant

Zaniewski Dawid, Klimaszewski Piotr, Witanowski Łukasz, Jędzejewski Łukasz, Klonowicz Piotr, Lampart Piotr

Archives of Thermodynamics

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2019

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Vol. 40, no 3

137--157

EN

Turbine stages can be divided into two types: impulse stages and reaction stages. The advantages of one type over the second one are generally known based on the basic physics of turbine stage. In this paper these differences between mentioned two types of turbines were indicated on the example of single stage turbines dedicated to work in organic Rankine cycle (ORC) power systems. The turbines for two ORC cases were analysed: the plant generating up to 30 kW and up to 300 kW of net electric power, respectively. Mentioned ORC systems operate with different working fluids: DMC (dimethyl carbonate) for the 30 kW power plant and MM (hexamethyldisiloxane) for the 300 kW power plant. The turbines were compared according to three major issues: thermodynamic and aerodynamic performance, mechanical and manufacturing aspects. The analysis was performed by means of the 0D turbomachinery theory and 3D computational aerodynamic calculations. As a result of this analysis, the paper indicates conclusions which type of turbine is a recommended choice to use in ORC systems taking into account the features of these systems.

8

A case study of working fluid selection for a small-scale waste heat recovery ORC system

Klimaszewski Piotr, Zaniewski Dawid, Witanowski Łukasz, Suchocki Tomasz, Klonowicz Piotr, Lampart Piotr

Archives of Thermodynamics

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2019

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Vol. 40, no 3

159--180

EN

The paper illustrates a case study of fluid selection for an internal combustion engine heat recovery organic Rankine cycle (ORC) system having the net power of about 30 kW. Various criteria of fluid selection are discussed. Particular attention is paid to thermodynamic performance of the system and human safety. The selection of working fluid for the ORC system has a large impact on the next steps of the design process, i.e., the working substance affects the turbine design and the size and type of heat exchangers. The final choice is usually a compromise between thermodynamic performance, safety and impact on natural environment. The most important parameters in thermodynamic analysis include calculations of net generated power and ORC cycle efficiency. Some level of toxicity and flammability can be accepted only if the leakages are very low. The fluid thermal stability level has to be taken into account too. The economy is a key aspect from the commercial point of view and that includes not only the fluid cost but also other costs which are the consequence of particular fluid selection. The paper discusses various configurations of the ORC system – with and without a regenerator and with direct or indirect evaporation. The selected working fluids for the considered particular power plant include toluene, DMC (dimethyl carbonate) and MM (hexamethyldisiloxane). Their advantages and disadvantages are outlined.

9

Criteria for selection of working fluid in low-temperature ORC

Mikielewicz D., Mikielewicz J.

Chemical and Process Engineering

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2016

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Vol. 37, nr 3

429--440

EN

The economics of an ORC system is strictly linked to thermodynamic properties of the working fluid. A bad choice of working fluid could lead to a less efficient and expensive plant/generation unit. Some selection criteria have been put forward by various authors, incorporating thermodynamic properties, provided in literature but these do not have a general character. In the paper a simple analysis has been carried out which resulted in development of thermodynamic criteria for selection of an appropriate working fluid for subcritical and supercritical cycles. The postulated criteria are expressed in terms of non-dimensional numbers, which are characteristic for different fluids. The efficiency of the cycle is in a close relation to these numbers. The criteria are suitable for initial fluid selection. Such criteria should be used with other ones related to environmental impact, economy, system size, etc. Examples of such criteria have been also presented which may be helpful in rating of heat exchangers, which takes into account both heat transfer and flow resistance of the working fluid.

10

Nowe materiały i procesy w konwersji oraz przechowywaniu energii - wybrane zagadnienia

Zoń J., Gnutek Z.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2015

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z. 87 [291], nr 2

187--196

PL

Na podstawie studiów literaturowych wybrano i przytoczono przykłady obecnie stosowanych technologii i materiałów do konwersji oraz przechowywania energii. Mając na uwadze z jednej strony rosnące zapotrzebowanie na energię, z drugiej zaś bogactwa naturalne oraz warunki klimatyczne, wybrano kilka zagadnień, dla których w zarysie przedstawiono obecny stan badań oraz podano literaturę. Studia literaturowe przeprowadzono, opierając się na bazach danych SciFinder i Current Contents, w perspektywie ostatnich czterech lat. Tylko w wyjątkowych przypadkach sięgano do starszej literatury.

EN

On the basis of literature studies the examples of currently used technologies and materials for energy conversion and storage were selected and described. Taking into consideration increasing domestic demand for energy, limited resources and climate conditions, authors have presented several energy conversion and storage related topics. Literature studies were carried out on the basis of databases SciFinder and Current Contents in perspective past four years. Only in exceptional cases dating back to the older literature.

11

Utilization of heat recovered from compressed gases in an oxy-combustion power unit to power the Organic Rankine Cycle module

Kotowicz J., Job M., Bartela Ł., Brzęczek M., Skorek-Osikowska A.

Journal of Power Technologies

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2015

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Vol. 95, nr 4

239--249

EN

Oxy-combustion technology is a zero-emission technology with great potential for commercial use in the near future. Application of this technology is linked with high energy losses in oxygen production and preparation of captured CO2 for transport to a storage place. In the analyzed oxy-combustion power plant with cryogenic air separation unit the compression of gases is responsible for most of the energy consumption. Compressed gases are sources of significant amounts of waste heat energy. Effective use of this energy is crucial to reducing the efficiency drop caused by additional installations. One method extensively examined in the literature for effective utilization of medium-grade and low-grade waste heat energy is the application of the Organic Rankine Cycle (ORC), which uses a low-boiling medium to produce additional electric power. The paper presents the results of analyses of the use of heat recovered from three sources identified in the oxy-combustion unit to power the ORC module. This includes heat from gases in the compression installations within the air separation unit, the CO2 processing unit and the CO2 compression installation. Thermodynamic and economic analyses were performed to assess the potential investment.

12

The laboratory test stand of the ORC micro power plant

Breńkacz Ł., Bykuć S., Żywica G., Kaczmarczyk T., Bagiński P.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2014

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nr 146

47--56

EN

The article presents the design and implementation of the laboratory test stand of the micro power plant with an Organic Rankine Cycle (ORC). The test stand was created to research different constructions of micro-turbines operating on a low-boiling agent. The electric power of these micro-turbines is 2-3 [kW]. There are measuring sensors connected to the test stand, which are necessary to collect information about the work of the whole ORC system. This laboratory test stand was built in the Szewalski Institute of Fluid Flow Machinery in Gdansk. The research on the newly constructed test stand were performed and some of the results are shown in this article.

13

Experimental investigation of the ORC system in a cogenerative domestic power plant with a scroll expanders

Kaczmarczyk T., Z., Ihnatowicz E., Żywica G., Kiciński J.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2014

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nr 145

59--60

EN

The paper presents the results of experimental investigations of the ORC system with two scroll expanders which have been used as a source of electricity. The working fluid was HFE-7100 – a newly engineered fluid with a unique heat transfer and favourable environmental properties. In the ORC system three heat exchangers were used (evaporator, regenerator, condenser) and before expanders the droplet separator was installed. As a source of heat an innovative biomass boiler was used. Studies have been carried out for the expanders worked in series and in parallel. The paper presents the thermal and fluid-flow properties of the ORC installation for the selected flow rates and different temperatures of the working medium. The characteristics of output electrical power, operating speed and vibrations for scroll expanders were also presented.

14

Utilisation of geothermal energy in a geothermal hybrid power plant as compared with that in a traditional geothermal ORC power plant

Borsukiewicz-Gozdur A., Stachel A., Nowak W.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

|

2008

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nr 133

69--76

EN

A comparative assessment of operation of two power plant schemes is presented by usig appropriate mathematical models. The principal scheme incorporates a geothermal hybrid power plant with a traditional water steam boiler and a steam turbine in the upper temperature range, and an ORC turbine loop in the lower temperature range. Operation of the principal scheme is then compared with such of its individual loops, i.e. of the (reference) water steam power plant (energy input from the steam boiler and from the geothermal source) and of the geothermal ORC power plant. Calculations of power and efficiency have been carried out at comparable operation conditions in all considered cases.

15

Biomasowe elektrociepłownie

Okonek M.

Rynek Instalacyjny

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2004

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Nr 6

74--75

PL

Obecnie wiele uwagi poświęca się generacji energii z wykorzystaniem odnawialnych źródeł energii. Czyni się tak, zarówno ze względów technicznych, jak i ekonomicznych. W produkcji energii na poziomie 0,2-1,0 MWel można zastosować technologie oparte na ślimakowym silniku parowym lub organicznym cyklu Rankine’a. Inwestycje te mają duże szanse na uzyskanie wsparcia ze środków z funduszy strukturalnych oraz innych źródeł finansowych UE, wspomagających działania z zakresu poszanowania i efektywnego wykorzystania energii, redukcji emisji CO2 oraz wzrostu bezpieczeństwa dostaw energii.