Research and development of CO2 Capture and Storage Technologies in Fossil Fuel Power Plants

This paper presents the results of a research project on the suitability of post-combustion CCS technology in the Czech Republic. It describes the ammonia CO2 separation method and its advantages and disadvantages. The paper evaluates its impact on the recent technology of a 250 MWe lignite coal fired power plant. The main result is a decrease in electric efficiency by 11 percentage points, a decrease in net electricity production by 62 MWe, and an increase in the amount of waste water. In addition, more consumables are needed

High mercury emission (both forms: Hg0 and Hg2+) from the wet scrubber in a full-scale lignite-fired power plant

The paper describes and discusses the results of research on mercury behaviour, especially its high emission, in both forms: elemental (Hg-0) and oxidised (Hg2+) from the wet flue gas desulphurisation scrubber (WFGD) in a lignite-fired power plant located in central Europe. The presented results involve the collection of lignite power plant samples (liquid, solid, gas) and different laboratory chemical analyses to try to understand the mechanism of mercury re-emission from the wet flue gas desulfurization system. It was noted that 67-80% of the total inlet mercury concentration left the WFGD scrubber. Moreover, the oxidised form of mercury was the main emitted form (about 60-70% of the total mercury concentration). The results show that mercury was found in very high concentration (10 mu g/g) (range: ppm) in the WFGD solid by-products, whereas the liquid phase contained only 1 mu g//l (range: ppb). Considering literature reports and presented data from the investigated power station, we believe that iron (Fe), which occurs in very high concentrations in solid WFGD samples (1.81% wt. Fe) and lignite (up to 20 g/kg Fe) is mainly responsible for disrupting the mercury absorption in the scrubber, the partitioning of the mercury between phases and leads to its reemission. Moreover, we believe also that a relatively high iodine ion concentration (130 mg/l) in the limestone slurry leads to mercury emission in its oxidised form, mainly as Hgl(2), which is highly volatile. Other minor components from limestone dissolution such as Mn, Al and Mg may additionally enhance that "complex" mercury behaviour.Web of Science270art. no. 11749

PREDICTION OF NOX EMISSIONS FOR FBC BOILERS BY EMPIRICAL MODELS – THE INFLUENCE OF SCALE-UP

Reliable prediction of NOX emissions can provide useful information for boiler design and fuel selection. The disadvantages and complexity of recently used kinetic NOX prediction models could be overcome by developing a simple empirical model. However, existing empirical models for prediction of NOX are used exclusively for pulverized coal boilers. This paper aims to modify some commonly used pulverized coal combustion empirical NOX prediction models – Pohl´s model and Ibler´s model – to fit the fluidized bed combustion boilers. The data from large scale fluidized bed combustion units are used for empirical models modification and compared with the data from pilot scale 0.5 MW fluidized bed combustion boiler. The reliability of proposed modifications to physical models and the influence of scale-up are discussed. The maximum reliability was achieved by modified Ibler´s model. If fuel mixtures were excluded the reliability increased. The NOX emissions of pilot scale boiler were higher compared to large scale units. However, these values were in agreement with Ibler´s model prediction, meaning the cause of higher values are fuel and combustion parameters and not the scale-up

Experimental verification of the efficiency of selective non-catalytic reduction in a bubbling fluidized bed combustor

Controlling nitrogen oxide (NOX) emissions is still a challenge as increasingly stringent emission limits are introduced. Strict regulations will lead to the need to introduce secondary measures even for boilers with bubbling fluidized bed (BFB), which are generally characterized by low NOX emissions. Selective non-catalytic reduction has lower investment costs compared to other secondary measures for NOX reduction, but the temperatures for its efficient utilization are difficult to achieve in BFBs. This paper studies the possibility of an effective application of selective non-catalytic reduction (SNCR) of nitrogen oxides in a pilot-scale facility with a bubbling fluidized bed. The effect of temperatures between 880 and 950 °C in the reagent injection zone on NOX reduction was investigated. For the selected temperature, the effect of the amount of injected reagent, urea solution with concentration 32.5%wt., was studied. The experiments were carried out using 500 kWth pilot scale BFB unit combusting lignite. In addition, an experiment was performed with the combustion of wooden pellets. With reagent injection, all experiments led to the reduction of nitrogen oxides and the highest NOX reduction of 58% was achieved

Experimental verification of the efficiency of selective non-catalytic reduction in a bubbling fluidized bed combustor

Controlling nitrogen oxide (NOX) emissions is still a challenge as increasingly stringent emission limits are introduced. Strict regulations will lead to the need to introduce secondary measures even for boilers with bubbling fluidized bed (BFB), which are generally characterized by low NOX emissions. Selective non-catalytic reduction has lower investment costs compared to other secondary measures for NOX reduction, but the temperatures for its efficient utilization are difficult to achieve in BFBs. This paper studies the possibility of an effective application of selective non-catalytic reduction (SNCR) of nitrogen oxides in a pilot-scale facility with a bubbling fluidized bed. The effect of temperatures between 880 and 950 °C in the reagent injection zone on NOX reduction was investigated. For the selected temperature, the effect of the amount of injected reagent, urea solution with concentration 32.5%wt., was studied. The experiments were carried out using 500 kWth pilot scale BFB unit combusting lignite. In addition, an experiment was performed with the combustion of wooden pellets. With reagent injection, all experiments led to the reduction of nitrogen oxides and the highest NOX reduction of 58% was achieved

Applicability of Secondary Denitrification Measures on a Fluidized Bed Boiler

This article compares performance of selective catalytic reduction (SCR) and selective non-catalytic reduction (SNCR) applied on the same pilot unit, a 500 kW fluidized bed boiler burning Czech lignite. Correlation of the denitrification efficiency on the normalized stoichiometric ratio (NSR) is investigated. The fundamental principle of the SCR and SNCR is similar with the same reaction scheme. The difference is in the use of the catalyst that lowers the activation energy of the key reaction. As a result, the reduction is performed in the SCR method at lower temperatures. During experiments, the NSR was up to 1.6 for the SCR method. For the SNCR method, which has a higher reducing agent consumption, maximum denitrification efficiency was reached for NSR about 2.5. The efficiency of both secondary methods was investigated. The denitrification efficiency during experiments exceeded 98 % for the SCR method, and the SNCR method, together with the primary measures, reached an efficiency of 58 %

Additive desulphurization by sodium bicarbonate in pulverized-fuel furnaces

Import 31/08/2009PILAŘ, L. Aditivní odsiřování hydrogenuhličitanem sodným v práškových ohništích. VŠB – TU Ostrava, Fakulta strojní, Katedra energetiky, 2009, počet stran 117, Disertační práce, školitel Kadlec, Z. Hlavní cílem disertační práce je posoudit možnost eliminace oxidů siřičitého ze spalin pod emisní limit 200 mg/mN3 pomocí hydrogenuhličitanu sodného NaHCO3, který je dávkován do spalinového traktu před elektrostatický odlučovač popílku, tedy použití suché aditivní metody pro eliminaci oxidu siřičitého ze spalin. Zkušební odsiření metodou eliminace oxidu siřičitého ze spalin pomocí hydrogenuhličitanu sodného bylo provedeno poprvé v České republice na kotli o parním výkonu 220t/h. Obsahově je disertační práce rozdělena na několik kapitol, které se sebou úzce souvisí a je nezbytné tyto informace pro podrobnost disertační práce v textu uvézt. Jak bylo výše napsáno, je disertační práce rozdělena na několik tematicky souvisejících kapitol. První kapitola disertační práce je podána jako rešeršní část stávající energetické náročnosti jak v České republice, tak i v EU a ve světě. V této první kapitole jsou dále uvedeny legislativní stránky zdrojů emisí SO2 a emisní limity těchto zdrojů dle zákona 146/2007sb., protože hlavním cílem disertační práce je eliminace oxidů síry ze spalin. Popisovaná kapitola také pro úplnost uvádí roční emise SO2 zdrojů znečištění velkých a zvláště velkých zdrojů v České republice. Cílem popisované teoretické rešeršní části disertační práce je uvézt informace o energetických bilancích, legislativních stránkách produkce emisí SO2 a roční emise SO2 zdrojů znečištění velkých a zvláště velkých zdrojů, vše v rámci České republiky. Disertační práce v další následující kapitole podrobně popisuje teoretickou část eliminace oxidů síry zahrnující jak primárních opatření, tak i sekundárních opatření. V rámci této druhé teoretické kapitoly popisující možností eliminace oxidů síry je popsána problematika eliminace oxidů siry a v úplnost a zpřesnění této kapitoly jsou uvedeny ucelené informace zahrnující vápenné a uhelné hospodářství v energetických zařízeních společnosti ČEZ, a. s., jako společnost, která pokrývá převážnou část spotřeby České republiky elektrickou energii. Výše uvedené obsahy jednotlivých kapitol zahrnují jen teoretickou, ale hlavní cíl disertační práce je provedení experimentálního odsiřovacího testu a zjištění možnosti eliminace oxidu siřičitého pod emisní limit 200 mg/mN3 pomocí suché metody jiným aditivem než CaCO3. V experimentu byl použit přípravek na bázi hydrogenuhličitanu sodného NaHCO3, který byl po rozemletí na požadovanou frakci dávkován do spalinového traktu před elektrostatický odlučovač popílku. Tento cíl, tj. možnost eliminace oxidu siřičitého pod zbytkovou koncentraci 200 mg/mN3 pomocí přípravku na bázi hydrogenuhličitanu sodného je podložen měřeními plynných emisí před místem vhánění přípravku na bázi NaHCO3 a následným měření plynných emisí SO2 za elektrostatickým odlučovačem před spalinový ventilátor a také provedením chemických analýz popílků odebraných z jednotlivých sekcí elektrostatického odlučovače.PILAŘ, L. Additive desulphurization by sodium bicarbonate in pulverized-fuel furnaces. VŠB – TU Ostrava, Faculty of Mechanical Engineering, Department of Power Engineering, 2009, number of pages 117, Dissertation, supervisor Kadlec, Z. The main objective of the dissertation is to assess the effectivity of reduction of sulphur oxides content in combustion products below the 200 mg/mN 3 emission limit by dosing sodium bicarbonate NaHCO3 into the flue ways before the electrostatic fly-ash separator, i.e. employing the dry additive method of reducing the content of sulphur oxides in combustion products. The first experimental desulphurization in the Czech Republic, employing the sodium bicarbonate additive method, was performed with the use of a 220t/h boiler. The thesis is divided into several, closely related chapters quoting all indispensable information. The thesis, as mentioned above, is divided into several thematically related chapters. The initial chapter deals with the current energy demandingness in the Czech Republic, EU and in other parts of the world. It further quotes the legislative issues concerning sources of SO2 emissions and their limits, in accordance with the Act 146/2007Coll., as the main goal of the dissertation is elimination of sulphur oxides in combustion products. In order to provide a full view, this chapter quotes a range of data concerning annual SO2 emission values of some major sources in the Czech Republic. The objective of the theoretical part of the thesis is to bring out information concerning energy budgets, legislative issues, yearly values, and substantial SO2 emission sources in the Czech Republic. The following chapter brings a detailed description of the theoretical part concerning reduction of sulphur oxides, including both primary and secondary measures. The second chapter, dealing with an in-depth view of the problems related to elimination of sulphur oxides, further offers overall information on lime and coal management of ČEZ, a.s., representing the company which covers a major part of electric energy consumption in the Czech Republic. The above mentioned chapters introduce the theoretical part of the thesis. However, the main objective of the work is carrying out of an experimental desulphurization test the purpose of which is to find out and explore the possibilities of reducing the levels of sulphur oxides below the emission limit of 200 mg/mN 3 by way of a dry method using a different additive than CaCO3. During the experiment, a sodium bicarbonate NaHCO3 based preparation was used. This preparation was firs ground to a required fraction and fed consequently into the flue ways before the electrostatic fly-ash separator. The whole experiment is supported by gaseous emission measurements located before the point where the NaHCO3 based preparation is fed to the flue ways, as well as subsequent measuring of SO2 gaseous emissions behind the electrostatic fly-ash separator. The results are further supported by chemical analyses of fly-ash samples from individual sections of the separator.Prezenční361 - Katedra energetikyvýborn

The importance and use of compression garments in sports

Title: The importance and use of compression garments in sports Objectives: The main aim of this thesis was to analyze the effect of compression garments on performance and recovery in sports. Methods: The work is realized as a review. There were searched three electronic databases: PubMed, Web of Science and Scopus for obtaining possible relevant papers. The same keywords were used to search in all the databases. Results: Based on the study of scientific literature, it was found that compression garments could provide a positive effect only under certain conditions. For speed-strength sports, the compression garments do not improve performance; however, they can reduce pain and fatigue after sports performance. In endurance sports, they can reduce heart rate and help ease the breakdown of lactate after exercise. Conclusion: Compression garments can improve conditions for sports performance, but their impact has not been fully demonstrated yet. Keywords: compression socks, recovery, regeneration, lactate, perceived pai

Proposal of volume compensator new conception for water nuclear power

Import 03/05/2007Prezenční361 - Katedra energetik

Simulace procesů v jaderné elektrárně Temelín

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Fakulta strojní. Katedra (361) energetik