15 research outputs found
Study connective capabilities of solid residues from the waste incineration
Rostoucí problémy se získáváním přírodních surovin a energie, rostoucí celospolečenský význam ochrany životního prostředí a rozvoj nových technologických postupů způsobilo, že se změnila původní tendence výrobců, zbavovat se odpadů jako bezcenných látek. Z hlediska ochrany životního prostředí je možno konstatovat, že spalování se řadí mezi bezpečné způsoby odstraňování komunálních i nebezpečných odpadů a pro mnohé druhy odpadů se jedná o jediný způsob jeho bezpečného odstranění. Při termickém odstraňování odpadů vzniká několik typů sekundárních tuhých odpadů, které je nutno bezpečně deponovat nebo přepracovat. Hlavní dopady na životní prostředí jsou spojeny s jejich nakládáním, manipulací a použitím.
Vzhledem k tomu, že složení sekundárních tuhých zbytků je velmi různorodé, je potřeba zhodnocení jejich nebezpečných vlastností. Popel/škvára obsahují poměrně vysoké hodnoty oxidů těžkých kovů, jež mohou představovat značné nebezpečí z hlediska výluhů při nevhodném deponování na skládky. Dalším tuhým podílem po spalování odpadů je popílek, který je řádově nebezpečnější než škvára/popel. V současné době probíhá intenzivní hledání nových možností využití tuhých zbytků po spalování odpadů. Je kladen důraz na řízení procesu jejich předběžné úpravy. Vhodné postupy mohou minimalizovat případy nesprávného použití.
Pro experimentální část práce byly vybrány vzorky tuhých zbytků po spalování odpadů ze spaloven nebezpečných a komunálních odpadů v ČR. Byla prověřena jejich schopnost vytvářet kompaktní celek s účinkem konvenčního anorganického pojiva nebo bez něj. Zájem o prozkoumání pojivových schopností těchto látek vychází z požadavku imobilizace jejich toxických součástí. Výsledkem by měl být kompaktní materiál, jehož vodní výluh umožní bezpečné uložení, těchto častokrát nebezpečných odpadů.Growing problems with the acquisition of natural raw materials and energy, the growing social importance of environmental protection and the development of a new technological processes have caused that the original tendency of manufacturers has changed, to dispose of wastes as worthless substances. From the point of view of environmental protection, it can be stated that combustion is one of the safe ways of disposal of municipal and hazardous waste and for many types of waste it is the only way of its safe disposal. Several types of secondary solid waste arise in thermal waste disposal, which must be safely deposited or reprocessed. The main environmental impacts are associated with their management, handling and use.
Given the situation, that the composition of secondary solid residues is very diverse, an assessment of their hazardous properties is needed. The ash / slag contains relatively high values of heavy metal oxides, which may pose a significant risk of leaching when improperly deposited in landfills. Another solid fraction after waste incineration is fly ash, which is more dangerous than slag / ash. Currently, there is an intensive search for new possibilities for the use of solid residues for waste incineration. Emphasis is placed on the process of their preliminary adjustment in the preparation. Appropriate procedures can minimize cases misuse.
Samples of solid residues after incineration of waste from hazardous and municipal waste incinerators in the Czech Republic were selected for the experimental part of the thesis. Their ability to form a compact unit with or without conventional inorganic binder has been examined. The interest in exploring the binding properties of these substances is based on the requirement to immobilize their toxic components. The result should be a compact material whose water leachate allows safe storage of these often hazardous wastes.635 - Katedra tepelné technikyvyhově
Numerical modeling of batch formation in waste incineration plants
nefunkční DOIThe aim of this paper is a mathematical description of algorithm for controlled assembly of incinerated batch of waste. The basis for formation of batch is selected parameters of incinerated waste as its calorific value or content of pollutants or the combination of both. The numerical model will allow, based on selected criteria, to compile batch of wastes which continuously follows the previous batch, which is a prerequisite for optimized operation of incinerator. The model was prepared as for waste storage in containers, as well as for waste storage in continuously refilled boxes. The mathematical model was developed into the computer program and its functionality was verified either by practical measurements or by numerical simulations. The proposed model can be used in incinerators for hazardous and municipal waste.Web of Science1716
Experience with application of reagent to heat transfer surfaces of combustion device
The formation of deposits on heat exchange surfaces of combustion equipment causes a decrease in heat exchange, a decrease in power, and consequently deterioration in the economic balance of combustion equipment. The technology of French company A. I. T. DRIVEX has been developing and being applied in practice for many decades. Preventive technology is used as a mean reagent periodically injected during operation into the combustion chamber. Part of the application is always pre-prepared project resolving the location of the injection nozzles into the combustion chamber on the flue gas path. The article describes the experimental usage of reagent GEPERSUITE 2200 at the Sermaize refinery in France. The aim of the test is to evaluate the benefits and advantages of applied technology in the boiler refinery in full operation. The results clearly demonstrate that using the reagent GEPERSUITE 2200 is advantageous in terms of economic and technical propertiesWeb of Science1925
Characterization of tar deposits, extraction and sorption properties
The main goal of this paper was to characterize and find a useful solution for the decomposition of tar deposits. For the experimental part, tar deposits, formed by polymerization and condensation reactions, were chosen from a storage tank for tars. At first the initial analyses of tar deposits (elemental, thermogravimetric, and calorimetric analyses) were performed. After the characterization, the tar deposits were extracted in the Soxhlet extractor by acetone, toluene, and quinolone and activated with potassium hydroxide. As the final step of this work, the sorption characterization on the 3Flex Surface Characterization Analyzer (Micromeritics) was performed. The specific surface area of the samples was evaluated using two methods – a single point measurement at p/p0=0.2 and BET method. Micropore and external surface areas were calculated based on a t-plot analysis (carbon black model)
Effects of kaolin additives in fly ash on sintering and properties of mullite ceramics
The effective utilization of fly ash (FA) as a raw material for ceramics production is performed on the FA-kaolin mixtures containing kaolins 10% by mass. The mixtures in comparison with FA and three raw kaolins were annealed to mullite ceramics at temperatures of 1000, 1100, 1200 and 1300 degrees C. The main aims were to contribute to the discussion on the effect of impurity of Na,K-feldspars in kaolins and Fe2O3 in FA on sintering procedure, porous ceramics properties and mullite structural properties. The phases were characterized using X-ray diffraction and thermogravimetry DTA/TGA methods. Mercury intrusion porosimetry was used for characterization of porosity of ceramic samples. Results evidenced the influence of feldspars in kaolins and Fe2O3 in FA on the sintering temperatures and properties of mullite ceramics. The fully FA-based ceramic sintered at 1100 degrees C exhibited post-sintering properties of bulk density 2.1 g/cm(3); compressive strength 77.5 MPa; and porosity, 2% in comparison with the FA/kaolin-based ceramics properties of bulk density 2.2 g/cm(3); compressive strength, 60-65 MPa; and porosity from 9.3 to 16.4% influenced by Na,K-feldspars. The best structural and mechanical characteristics were found for the FAK3 sample, supported by the high content of kaolinite and orthoclase in the kaolin K3 additive. The FAK3 annealed at 1100 degrees C exhibited good compressive strength of 87.6 MPa at a porosity of 10.6% and density of 2.24 g/cm(3) and annealed at 1300 degrees C the compressive strength of 41.3 MPa at a porosity of 19.2% and density of 1.93 g/cm(3).Web of Science118art. no. 88
Comparison of Public Procurement Systems in Selected Public Administration Authorities
Import 19/10/2011VŠB – Technická univerzita Ostrava, Ekonomická fakulta, Katedra veřejné ekonomiky
Jméno a příjmení autora: Bc. Veronika Blahůšková
Název bakalářské práce: Srovnání systémů zadávání veřejných zakázek ve vybraných úřadech veřejné správy
Diplomová práce se zabývá srovnáním veřejných zakázek ve vybraných úřadech veřejné správy. Pozornost je věnována systému zadávání veřejných zakázek malého rozsahu ve vybraných úřadech obcí s rozšířenou působností v Moravskoslezském kraji. Pro všechny kategorie zadavatelů v tomto případě platí, že nejsou povinni zadávat veřejné zakázky malého rozsahu podle zákona. Cílem diplomové práce je analýza a zhodnocení postupů zadávání a návrh doporučení pro zlepšení postupu zadávání veřejných zakázek malého rozsahu. Z výsledků hodnocení vyplynulo, že úřady obcí s rozšířenou působností v Moravskoslezském kraji nemají pro své odbory a jimi zřizované příspěvkové organizace detailně popsaný metodický postup, který je využíván při zadávání veřejných zakázek malého rozsahu.Name and Surname: Bc. Veronika Blahůšková
Title of Thesis: Comparison of Public Procurement Systems in Selected Public Administration Authorities
This thesis focuses on the comparison of public procurement in selected public administration. Attention is given to the public procurement system in selected small-scale offices of municipalities with extended powers in the Region. For all categories of buyers in this case, they are not obliged to award minor contracts under the law. The aim of this thesis is analysis and evaluation of procurement practices and draft recommendations for improving the procurement process, a small scale. The evaluation results showed that the authorities of municipalities with extended powers in the Region to have their unions and their semi-established organization that is described in detail the methodology that is used for procurement of small scale.153 - Katedra veřejné ekonomikyvýborn
Public Procurement Processed by the Town
Import 01/09/2009Prezenční153 - Katedra veřejné ekonomikyvelmi dobř
Study connective capabilities of solid residues from the waste incineration
Currently there is increasingly closer interaction between the importance of environmental protection and efficient promoting of scientific and technological progress in the field of waste incineration. Waste is not only undesirable source of pollution, but if it is effectively used it also has great economic importance. In the Czech Republic 34.5 million tonnes of all wastes was produced in 2017, of which 5.7 million tonnes of municipal waste. 50% of the produced municipal waste was used, 38% of which was used for the material and 12% for energy utilization. 45% of municipal waste was deposited in the landfills. The method of waste incineration is among the major tools to reduce the landfill waste. The use or processing of the product which the process of incineration of municipal and hazardous waste generated can be considered as an obstacle to the favorable reception of this process. Apart from flammable components, waste also contains certain amount of dangerous particles. This is especially the sulfur chlorides, fluorine, PCBs and other heavy decomposable organic substances and heavy metals. This fact puts high demands on the gas cleaning processes followed by neutralization of other products that the incinerator leaves, in which these substances can be contained in higher concentrations than in the original waste. For this reason subsequent stabilization of these toxic substances is necessary to ensure new environmental burdens are avoided when not used properly. The major part of the waste combustion process is made up of ash and slag. One of the most common ways of dealing with these solid residues is disposing them to avoid creating new hazardous waste landfills. Other filtering waste also passes hazardous waste stabilization process before landfilling. Currently there is intensive search for new possibilities for utilization of solid residues from incineration. Nowadays there is emphasis on process control of their pretreatment for the production of draft procedure with its management. Appropriate procedures may minimize the instances of improper use.Web of Science2311055104
Characterization of Tar Deposits, Extraction and Sorption Properties
The main goal of this paper was to characterize and find a useful solution for the decomposition of tar deposits. For the experimental part, tar deposits, formed by polymerization and condensation reactions, were chosen from a storage tank for tars. At first the initial analyses of tar deposits (elemental, thermogravimetric, and calorimetric analyses) were performed. After the characterization, the tar deposits were extracted in the Soxhlet extractor by acetone, toluene, and quinolone and activated with potassium hydroxide. As the final step of this work, the sorption characterization on the 3Flex Surface Characterization Analyzer (Micromeritics) was performed. The specific surface area of the samples was evaluated using two methods - a single point measurement at p/p0=0.2 and BET method. Micropore and external surface areas were calculated based on a t-plot analysis (carbon black model)
Modelling of thermal processes at waste incineration
The article describes the possibilities of optimization of combustion processes at waste incineration, which require a specific approach in comparison with conventional fuels. The main cause is an instability of thermo-chemical properties of majority of waste. The work defines and evaluates criteria, which are critical for the waste incineration process. The numerical model “Combustion temperature” for optimization of thermal work of the waste incinerator was designed for support of implementation of other measures aimed at increasing the process energy efficiency, and it was verified in practice in real waste incineration plant.Web of Science38233533352