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Malted sorghum - cassava flour was formulated into blends to produce cookies. Sorghum grains were sorted, washed, steeped (12 hours), malted (48 hours) and oven dried. Freshly harvested cassava roots were manually peeled, washed, grated and dried (using hybrid solar dryer at 50oC). The dried malted sorghum grains and cassava were processed into flour and sieved. The blends were prepared by homogenously mixing malted sorghum flour and high quality cassava grate flour in varied proportion labelled as sample A (100 % Malted Sorghum Flour) Sample B (60 % Malted Sorghum Flour and 30 % Cassava Flour), sample C (70 % Malted Sorghum Flour and 30 % Cassava Flour) and Sample D (80 % Malted Sorghum Flour and 20 % Cassava Flour) separately prepared into cookies and subjected to proximate, mineral, anti-nutrients, physical and sensory analysis using standard analytical methods with chemicals of analytical grade. The result for moisture, Ash, Fat, Fibre, Protein, Carbohydrate and energy content for samples A, B, C and D respectively ranged from 3.11 % - 6.81 %; 1.41 % - 1.52 %; 21.66 % - 23.41 %; 2.20 % - 2.67 %; 4.41 % - 7.26 %; 60.86 % - 63.85 % 473.09 Kcal - 478.82 Kcal. The mineral result for sodium, potassium and calcium 15.06 mg/100 g, 12.70 mg/100 g, 14.40 mg/100 g and 17.00 mg/100 g; 24.70 mg/100 g, 28.17 mg/100 g, 21.60 mg/100 g and 25.17 mg/100 g; 11.30 mg/100 g, 13.10 mg/100 g, 10.09 mg/100 g and 10.09 mg/100 g respectively. The result recorded for colour ranged from 6.20 - 7.40; aroma was 6.30 - 7.30; taste ranged from 6.10 - 7.20; texture ranged from 5.60 - 5.90 and overall acceptability ranged from 5.70 - 6.50. It can be concluded that combination of Malted Sorghum and Cassava Flour in cookies production will help to enhance the utilization of both crops, nutritional intake, increase variety and reduce wheat importation.

This paper reports a theoretical study into the saw-type-grate section of a large litter cleaner in mounted cleaners that operate on a cotton harvester, as well as the theoretical and experimental justifications for its parameters. The effect exerted by a mounted cleaner on the process of cleaning raw cotton when processing in a cotton gin has been studied. A theoretical model of the impact of grates on weeds in cleaning processes has been developed. A condition for repelling the litter by grates and removing it from a cotton technological flow has been studied. The use of grates with a flat-shaped front edge allows for a steady reduction in the amount of damage in the raw cotton fiber, which improves the fiber quality and leads to a decrease in the number of defects and debris. The experimental and theoretical studies have produced evidence that enables the efficient operation of mounted-type cleaning machines in the cotton-cleaning industry. The movements of raw cotton as a viscoelastic body at the free impact of litter with the teeth of the saw against a stationary surface of the grate were investigated; the force schemes between the grates and saws were considered. The effect of a saw-type drum on the technological properties of raw cotton was investigated, namely on seed damage and the formation of the free fiber. A model of interaction between weed particles and grates was considered; the trajectories of the litter flight were shown in the function of the slope of the grate and the recovery factor. The issues of the relationship between the physical-mechanical properties of raw cotton, the elastic characteristics of raw cotton, and the impact force of cotton flies against the grate with a flat working face. Solving these issues could make it possible to determine the optimal structure of the raw cotton cleaning mechanisms, which would improve the effectiveness of cleaning raw cotton from weeds. Based on the identified functional links, it has become possible to construct new or improve existing structures of the saw-type grate section of mounted cleaners. Practical experience shows that the use of the designed structure in large litter cleaners of the mounted type produces a significant increase in the cleaning effect of the machine, Проведено теоретическое исследование пильчато-колосниковой секции очистителя крупного сора в навесных очистителях, функционирующей на хлопкоуборочной машине, теоретические и экспериментальные обоснования его параметров. Изучены влияния навесного очистителя на технологический процесс очистки хлопка-сырца при переработке на хлопкозаводе. Разработана теоретическая модель воздействия колосников на сорные примеси в очистительных процессах. Изучено условие отражения сора колосниками и вывод его из технологического потока хлопка. Применение колосников плоской формы передней грани обеспечивает устойчивое снижение количества поврежденностей в волокне хлопка-сырца, что повышает качество волокна и приводит к снижению суммы пороков и засоренности. В результате экспериментальных и теоретических исследований получены данные, которые позволяют организовать эффективную работу очистительных машин навесного типа в хлопкоочистительной промышленности. Исследованы движения хлопка-сырца как упруго-вязкого тела при свободном ударе сора зубьями пилы об неподвижную поверхность колосника, рассмотрены силовые схемы между колосниками и пилами. Рассмотрено влияние пильчатого барабана на технологические свойства хлопка-сырца, а именно на поврежденность семян и образование свободного волокна. Рассмотрена модель взаимодействия сорных частиц с колосниками, показаны траектории полета сора в функции наклона колосника и коэффициента восстановления. Исследованы вопросы взаимосвязи физико-механических свойств хлопка-сырца, упругих характеристик хлопка-сырца и силы удара летучки о колосник с плоской рабочей гранью. Решение этих вопросов даст возможность найти оптимальную конструкцию механизмов очистки хлопка-сырца, что приведет к повышению эффекта очистки хлопка-сырца от сорных примесей. На основе выявленных функциональных связей открывается возможность создания новых или совершенствования существующих конструкций пильчато-колосниковой секции очистителей навесного типа. Полученный опыт показывает, что применение разработанной конструкции в очистителях крупного сора навесного типа дает значительное увеличение очистительного эффекта машины, Проведено теоретичне дослідження пильчато-колосникової секції очищувача габаритного сміття в навісних очисниках, що функціонує на бавовнозбиральній машині, теоретичні та експериментальні обґрунтування його параметрів. Вивчено вплив навісного очищувача на технологічний процес очищення бавовни-сирцю при переробці на хлопкозаводі. Розроблено теоретичну модель впливу колосників на сміттєві домішки в очисних процесах. Вивчено умову відображення сміття колосниками та виведення його з технологічного потоку бавовни. Застосування колосників плоскої форми передньої грані забезпечує стійке зниження кількості пошкоджень у волокні бавовни-сирцю, що підвищує якість волокна та призводить до зниження суми вад і засміченості. В результаті експериментальних і теоретичних досліджень отримані дані, які дозволяють організувати ефективну роботу очисних машин навісного типу в хлопкоочисній промисловості. Досліджено рух бавовни-сирцю як пружно-в'язкого тіла при вільному ударі сміття зубами пилки об нерухому поверхню колосника, розглянуті силові схеми між колосниками та пилами. Розглянуто вплив пильчатого барабана на технологічні властивості бавовни-сирцю, а саме на пошкодженість насіння та утворення вільного волокна. Розглянуто модель взаємодії засмічених частинок з колосниками, показані траєкторії польоту сміття в функції нахилу колосника та коефіцієнта відновлення. Досліджено питання взаємозв'язку фізико-механічних властивостей бавовни-сирцю, пружних характеристик бавовни-сирцю та сили удару летючки об колосник з плоскою робочою гранню. Вирішення цих питань дасть можливість знайти оптимальну конструкцію механізмів очищення бавовни-сирцю, що призведе до підвищення ефекту очищення бавовни-сирцю від сміттєвих домішок. На основі виявлених функціональних зв'язків відкривається можливість створення нових або вдосконалення існуючих конструкцій пильчато-колосникової секції очищувачів навісного типу. Отриманий досвід показує, що застосування розробленої конструкції в очищувачах габаритного сміття навісного типу дає значне збільшення очисного ефекту машини

Na temelju zadanih podataka drvene rešetkaste krovne konstrukcije potrebno je dimenzionirati glavni nosač, sekundarni nosač konstrukcije i vjetrovne spregove te izraditi radioničke nacrte glavnog nosača te detalje dodatnih spojeva, Based on the given data of the lattice of the roof structure, it is necessary to dimension the main girder, the secondary girder of the structure, wind bracings and to make drawings of the main girder and details of additional joints

Potrebno je proračunati drvenu rešetkastu konstrukciju na temelju zadanih dimenzija glavnog nosača konstrukcije, lokacije zadane konstrukcije i zadanih svojstava drva. Navedeno obuhvaća dimenzioniranje svih elemenata glavnog rešetkastog nosača, sekundarne konstrukcije (podrožnica), prostorne stabilizacije (spregova), dimenzioniranje pripadajućih spojeva te proračun nosivosti konstrukcije uslijed djelovanja požara. Based on the given data of the wooden lattice roof structure, it is necessary to dimension on the main girder, the secondary girder of the structure, wind bracings, load-bearing capacity due to fire, and to make drawings of the main girder and details of additional joints

Na temelju zadanih podataka drvene rešetkaste krovne konstrukcije potrebno je dimenzionirati glavni nosač, sekundarni nosač konstrukcije i vjetrovne spregove te izraditi radioničke nacrte glavnog nosača te detalje dodatnih spojeva Based on the given data of the lattice of the roof structure, it is necessary to dimension the main girder, the secondary girder of the structure, wind bracings and to make drawings of the main girder and details of additional joints

[CA] En aquest projecte va a dissenyar-se i desenvolupar-se una reixa de grossos, amb neteja automàtica, per a les aigües residuals que entren a les estacions de bombament. És sabut que uns dels problemes a les estacions de bombament és; per una part, l'obstrucció de les reixes, impedint l'entrada de l'aigua; i, d'altra banda, el pas d'objectes que poden danyar la maquinària o les instal·lacions hidràuliques. Per tant, l'objectiu principal d'aquest és el manteniment preventiu de la maquinaria i les instal·lacions hidràuliques., [EN] In this project the construction of a self-cleaning grate for the Campello and Sant Joan Wastewater Pumping Stations will be designed and developed. This pumping is directed to the Wastewater Treatment Plant in Alacantí Nord. It is well-known that one of the main problems at pumping stations is, on the one hand, the clogging of the grate which prevents the entry of water; and, on the other hand, the entry of objects that can damage the machinery and / or the hydraulic installations. Therefore, one of the main targets of this project is the preventive maintenance of the machinery and hydraulic installations. Another main goal of this work is to prevent workers from breathing hydrogen sulfide gas, as the grate must be manually cleaned.

Na temelju zadanih podataka drvene rešetkaste krovne konstrukcije potrebno je dimenzonirati glavni nosač, sekundarni nosač konstrukcije i vjetrovne spregove te izraditi radioničke nacrte glavnog nosača te detalje dodatnih spojeva., Based on the given data of the lattice of the roof structure, it is necessary to dimension the main girder, the secondary girder of the structure, and the wind bracings, and to make drawings of the main girder and details of additional joints.

Na temelju zadanih podataka drvene rešetkaste krovne konstrukcije potrebno je dimenzonirati glavni nosač, sekundarni nosač konstrukcije i vjetrovne spregove te izraditi radioničke nacrte glavnog nosača te detalje dodatnih spojeva. Based on the given data of the lattice of the roof structure, it is necessary to dimension the main girder, the secondary girder of the structure, and the wind bracings, and to make drawings of the main girder and details of additional joints.

Пояснювальна записка до дипломного проекту «Модернізація решітки сушарки псевдозрідженого шару для дослідження процесу псевдозрідження» містить 96 сторінок, 37 літературних джерел, 23 рисунків, 21 таблиць. В магістерській дисертації розглянуто сушарку з псевдозрідженим шаром та удосконалену частину апарату решітку сушарки псевдозрідженого шару. Решітка сушарки псевдозрідженого шару належить до галузі сушильних апаратів, які застосовують у лініях виробництва харчових продуктів та фармацевтичній галузі. Новим є те, що, решітка через яку проходить повітря має похилі отвори, які розташовані по спіралі Архімеда для створення вихрових потоків під час висушування матеріалу. Пропонована решітка сушарки псевдозрідженого шару забезпечує якісне висушування матеріалу та підвищує ефективність роботи даної сушарки. Для підтвердження працездатності та надійності конструкції були проведені тепловий, гідравлічний, конструктивний і міцнісний розрахунки елементів конструкції, було здійснено комп’ютерний аналіз та необхідні розрахунки в програмі «Ansys» для перевірки працездатності апарату. Проведений патентний пошук, за рахунок чого, виконаний порівняльний аналіз основних показників конструкції сушарки з діючими аналогами. Також у проекті розглянуті питання з монтажу та експлуатації теплообмінника. Розрахунки та креслення виконані згідно чинних стандартів, з використанням сучасних системних та інформаційних технологій. The explanatory note to the diploma project "Modernization of the fluidized bed dryer grid for the study of fluidization process" contains 96 pages, 37 literary sources, 23 drawings, 21 tables. The master's thesis deals with the fluidized bed dryer and the improved part of the apparatus of the fluidized bed dryer grid. The fluidized bed dryer grate belongs to the field of drying apparatus used in food production lines and the pharmaceutical industry. What is new is that the grate through which the air passes has sloping openings, which are arranged in an Archimedes spiral to create vortex flows during material drying. The proposed fluidized bed dryer grille provides high-quality drying of the material and increases the efficiency of the dryer. Thermal, hydraulic, structural and durable calculations of structural elements were carried out to confirm the construction's reliability and reliability, computer analysis and the necessary «Ansys» calculations were performed to verify the machine's performance. A patent search was carried out, whereby a comparative analysis of the main parameters of the design of the dryer with its existing analogues was performed. The project also addresses the issues of installation and operation of the heat exchanger. Calculations and drawings are made according to current standards, using modem system and information technologies.

In hearth furnaces, the firewood is burned more cleanly with less carbon monoxide at the outlet. The disadvantage of such fireboxes is a longer process of coal burnout than in grate-fired furnaces. In furnaces with a grate, the burnout time of coals is less, which makes it possible to finish the combustion process more quickly and close the outlet latch. This increases the efficiency of the furnace but to further reduce the time of burning out the coals they have to be raked and burned on the grate. This complicates the process of operating the furnace itself. The proposed design of the compound firebox allows us to improve characteristics of both the firebox itself and the entire furnace. Research objectives: creation and study of a compound firebox that increases the efficiency of the furnace and simplifies the furnace maintenance process with the values of carbon monoxide at the outlet comparable to hearth furnaces. Materials and methods: a detailed analysis of hearth fuel chambers ECO+ was carried out according to the amount of carbon monoxide at the outlet. The results of the analysis are used for comparison with compound fuel chamber. The structure of the compound firebox was chosen based on the results of preliminary tests of several fuel chambers proposed and tested by the author in the furnace PDKSh-2.0. A peculiarity of the structure of the compound firebox is the absence of a grate and the presence of a narrow slit in the lower part of the firebox through which the incoming air enters the firewood. Between the walls of the firebox and firewood, skids are installed, forming an air gap, through which the inlet air is uniformly supplied to the entire firewood supply. With gradual combustion of firewood and formation of coal, the firewood descends to the bottom of the firebox, where they intensively burn out in the maximum air flow. Compound firebox consists of several parts, it is made of steel with a thickness of 4.0 mm and installed into the furnace fire through the fuel entry door. In studying the combustion of firewood process, a gas analyzer and an anemometer are used. Results: the results of the test of the compound firebox showed that the combustion of firewood in it is more even and takes more time. The time of burnout of coals was reduced by 40...50 %. The actual value of the furnace efficiency is increased by 2...3 %, and the СО emissions are comparable with the ECO+ furnaces. Conclusions: compound firebox without a grate can be recommended for use in household furnaces for various purposes.

Пояснювальна записка складається з технологічної частини, параметричних, кінематичних та розрахунків на міцність, технології машинобудування та розділу охорони праці. Предметом дослідження був колосниковий грохот для механічного сортування матеріалу та модернізація дебалансного валу. Вивчено принцип роботи і конструкцію колосникових грохотів, виконано розрахунки, необхідні для модернізації колосникового грохоту. Модернізовано дебалансний вал, проведено розрахунки, що підтверджують працездатність модернізованої конструкції, в тому числі за допомогою ЕОМ. The explanatory note consists of a technological part, parametric, kinematic and strength calculations, technology engineering and occupational safety. The subject of the study was a grate rocket for mechanical sorting of the material and the upgrading of the unbalanced shaft. The principle of work and construction of grate craters was studied, the calculations necessary for the modernization of the grate crash were performed. The unbalanced shaft has been upgraded, calculations have been made, confirming the efficiency of the modernized design, including using a computer.

При розробці і проектуванні колосникового грохоту, на основі аналітичного огляду науково-технічної літератури, нормативної та конструкторської документації, патентних досліджень, інженерно-технічних розрахунків, виконано наступне: 1) вивчено принципи роботи і конструкцію промислових колосникового грохоту, проаналізовано технічні параметри і характеристики колосникового грохоту; 2) виконано ряд інженерних розрахунків, необхідних для розробки і проектування колосникового грохота, згідно з технічним завданням; 3) на основі виконаних патентних досліджень модернізовано систему приводу; 4) розроблено і проектовано колосникового грохоту з модернізацією системи приводу. In the development and design of a grid-iron screens, based on an analytical review of scientific literature, regulatory and design documentation, patent research, engineering calculations, the following: 1) studied the principles of operation and construction of industrial grate screens, analyzes the technical parameters and characteristics grate sifter ; 2) made a number of engineering calculations required for the development and design of vibrating grate, under terms of reference; 3) on the basis of the patent research upgraded drive system; 4) developed and designed grate sifter system with the modernization drive.

The combustion chamber and flues boiler radiant heat exchange occur between the gas (combustion products) and limiting gas surfaces of the combustion chamber and flues. In this case, part of the energy-emitted gas is absorbed by the surfaces, and part of it is reflected into the gas. The resulting heat flow between the gas and the surface defined by the difference between the amount of energy emitted by the gas on the surface, and the amount of energy absorbed by the gas from the radiation surfaces. The article presents the basic formulas for boilers on solid fuel with the movable grate. Calculations show that the change in volume of the furnace leads to a change in radiant heat transfer.

The accurate characterisation of flow from urban surfaces to sewer/stormwater systems is important for urban drainage design and flood modelling/risk identification. However, the geometrical complexity and large variety of drainage structures (linking elements) available makes model calibration and verification difficult. In this study an extensive comparison between experimentally measured and numerically modelled flow characteristics in the vicinity of ten different designs of manhole grate was performed under drainage flow in sub‐critical conditions. Using a 2D surface PIV (sPIV) system the work presents the first detailed characterisation of velocity fields around these linking elements. In addition, it provides the first detailed verification of the ability of a 2D numerical model to describe both velocity fields and drainage flows.\ud \ud \ud \ud The overall comparison shows a close relationship between numerical and the experimental results with some higher inflows in the experimental results as a consequence of a localised transition from weir to orifice condition near the void areas of the grates. It was also noted that velocity differences decreased further from the manhole, due mainly to the more directional flow. Overall the work demonstrates the potential for further use of 2D numerical models to describe flow conditions at linking elements, either directly within modelling simulations or indirectly via the characterisation of energy loss coefficients.

Electricity production from biomass has the potential to significantly contribute to the power mix in Portugal with lesser environmental impact than non-renewable resources. This study focuses on electricity production from the combustion of residual forest biomass from eucalypt logging activities in Portugal using life cycle assessment. In Portugal, several power plants fuelled by residual forest biomass have been commissioned in the last few years. Most of the installations use fluidised bed furnaces, and the others use grate furnaces. This study aims to compare the environmental impacts associated with these two alternative combustion technologies. System boundaries include the stages of forest management, collection processing and transportation and energy conversion. The default impact assessment method used is that suggested in the International Reference Life Cycle Data System. In a sensitivity analysis, calculations are performed using the ReCiPe method. For all of the impact categories analysed, the fluidised bed presents the smallest environmental impact. Even when the grate furnace efficiency increases and the fluidised bed efficiency decreases in the sensitivity analysis, the fluidised bed has lower impacts than the grate technology and can be the best alternative in the implementation of new power plants.

В статье предложено решение проблемы повышения технологической эффективности кон-струкции колосников очистителя волокнистого материала хлопка-сырца. Рассмотрены теоретические основы расчета и выбора параметров колосников очистителя хлопка-сырца. Приведены результаты испытаний реко-мендуемой конструкции очистителя с колосниками новой формы., The article proposes a solution to the problem of improving technological efficiency of the construc-tion of the grate cleaner for fibrous raw cotton material. The theoretical basis for the calculation and selection of param-eters of the grate raw cotton cleaner is considered. Results of tests of the recommended design of the cleaner with grate bars of the new form are presented.

In article questions of an assessment of the influence of technological processes of construction production on the environment are considered. Development of a new technique which will be able to consider the development of ecological influence for all the time of construction production is analysed, and also to satisfy the requirement of the branch for the management of the impact of construction on the environment during all duration of the process of construction production. Authors define the main objectives and the sequence of their decision. In the conclusion, the conclusion about the need for use of ecological safety for construction is drawn., {"references":["Afzini, M., & Neyestani B. (2011). Occupational Health and Safety in Construction Projects. Zenodo. doi:10.5281/zenodo.423096","Rane, N., Lopes, S., Raval, A., & Rumao, D. (2017). Study of effects of labour productivity on construction projects. International journal of engineering sciences & research technology, (6), 15-20. doi:10.5281/zenodo.802779","Dinesh, S., Sethuraman, R., & Sivaprakasam, Sh. (2017). The review on lean construction an effective approach in construction industry. International Journal of Engineering Research and Modern Education, Special Issue, 119–123. doi:10.5281/zenodo.570523","Gordeeva, O. V. (2003). Ekologicheskie trebovaniya po organizatsii stroitelno-montazhnykh rabot v usloviyakh goroda. Materialy IV nauchno-tekhnicheskoi konferentsii MIKKhiS","Berezhnyi, A. Yu. (2012). Formirovanie informatsionnoi bazy dannykh dlya sistemy otsenki ekologicheskoi effektivnosti organizatsionno-tekhnologicheskikh reshenii v protsesse stroitelnogo proizvodstva. Tekhnicheskoe regulirovanie. Stroitelstvo, proektirovanie i izyskaniya, (1), 42-43"]}

Magistrinio darbo metu buvo tiriama ir modernizuojama judančio ardyno biokuro pakura. Buvo modernizuojamas pakuros maitintuvas, pakuros hidraulinė sistema, pakuros ardynas. Po atliktų modernizavimo darbų buvo ištirta modernizavimo įtaka., Biofuel moving grate furnace was modernized and researched. Furnace feeder, hydraulic system and furnace grate was modernized. Influence of modernization was researched.

Веснік Віцебскага дзяржаўнага ўніверсітэта. - 2017. - № 4. - С. 26-28., В настоящей статье изучаются идемпотентные полугруппы линейных отношений, т.е. частичные многозначные линейные преобразования конечномерного векторного пространства над полем. = Idempotent semigroups of linear relations, i.e. partial multivalued linear transformations of finite vector space over the field, are studied in the article.

Generally, the temperature of flue gases at the furnace outlet is not measured. Therefore, a special computation procedure is needed to determine it. This paper presents a method for coordination of the numerical model of a pulverised fuel boiler furnace chamber with the measuring data in a situation when CFD calculations are made in regard to the furnace only. This paper recommends the use of the classical 0-dimensional balance model of a boiler, based on the use of measuring data. The average temperature of flue gases at the furnace outlet tk" obtained using the model may be considered as highly reliable. The numerical model has to show the same value of tk" . This paper presents calculations for WR-40 boiler. The CFD model was matched to the 0-dimensional tk" value by means of a selection of the furnace wall emissivity. As a result of CFD modelling, the flue gas temperature and the concentration of CO, CO2, O2 and NOx were obtained at the furnace chamber outlet. The results of numerical modelling of boiler combustion based on volumetric reactions and using the Finite-Rate/Eddy-Dissipation Model are presented.

Šiame darbe motyvuojamas kuro NOx redukavimo aktualumas. Įvertinama azoto oksidų daroma žala žmogui, gyvūnijai ir augmenijai. Apžvelgiama šiuo metu galiojanti Europos sąjungos taršos mažinimo direktyva LAND 43-2013 bei būsima direktyva 2013/0442. Teorinėje dalyje apžvelgiami azoto oksidų šaltiniai ir jų susidarymo mechanizmai. Šiame darbe detaliai aprašomos plačiai paplitusios ir dažnai praktikoje taikomos pirminės ir antrinės azoto oksidų mažinimo priemonės. Aptariami kiekvienos iš šių priemonių privalumai ir trūkumai. Tiriamojo darbo metodikoje pateikiama visa informacija apie eksperimentų metu naudotą matavimo įrangą, jos veikimo principus bei charakteristikas. Detaliai aprašytas eksperimentui naudotas kurą deginantis įrenginys. Eksperimentams atlikti pasirinktas tyrimo objektas – baldų gamybos pramonės atliekų granulės. Atliktas daug azoto turinčio kuro charakteristikų palyginimas su mediena ir kitomis kuro rūšimis. Eksperimentų eigoje NOx mažinimui buvo pasitelkti pirminiai ir antriniai NOx mažinimo metodai. Darbo pabaigoje pateikiami atliktų eksperimentinių tyrimų rezultatai. Ištirtų NOx koncentracijų redukavimo efektyvumai yra nurodomi grafiniu pavidalu. Jų rezultatai yra aprašyti ir analizuojami. Rezultatų apžvalgoje pateikiamas taikytų metodų tarpusavio efektyvumo palyginimas. Pateikiamos išvados dėl NOx redukavimo metodų efektyvumų. Įvertinta, kuriuos mažinimo metodus taikant galima deginti baldų pramonės gamybos atliekų granules, neviršijant direktyvose numatytų normų., The topicality of the fuel NOx reduction is motivated in this paper. The harm of nitrogen oxides for people, fauna and flora are evaluated. A review of European Union directives of pollution reducing LAND 43-2013 that is valid at this moment and the future directive 2013/0442 is made. In the theoretical part the source and formation mechanisms of nitrogen oxides are reviewed. Here you can find detailed information of wide and frequently used in practice primary and secondary reduction measures of nitrogen oxides. The advantages and disadvantages of these measures are discussed. In methodology of this research work you can find all information about all measuring equipment, working principles and characteristics that were used during experiments. A combustion plant used in the experiment is described widely. For the experimental inquiry a research object – furniture manufacturing waste pellets was chosen. This material with high quantities of nitrogen was compared to wood and other fuel varieties. During experimental investigation a primary and secondary NOx reduction methods were exercised. At the end of this paper experimental research results are presented. Examined effects of reduction of NOx reduction are plotted by graph. These results are described and analysed. A compare of methods effectiveness are plotted in a review of the results. A conclusion of various NOx reduction methods effectiveness is presented. A conclusion that determines NOx reduction effectiveness of various methods is made. An assessment of methods that allow the burning of furniture manufacturing waste pellets without exceeding pollution directives.

For improving the load-following capacity of existing grate boiler units, a model predictive control concept based on the combustion power soft-sensor is developed. Because the combustion power estimation has a very quick response to the primary air flow input, the load-following speed of the boiler control system will be improved considerably. The proposed model predictive control strategy is tested with the BioPower 5 combined heat and power plant data and the results are presented, analyzed, and discussed.

Thermal radiation is an important physical phenomenon in combustion environments. For the understanding of existing- and the design of new combustion environments computational modelling is a useful tool as it can describe the different transport phenomena. This thesis has focused on studying thermal radiative property models of the participating media, gases and particles. Two specific combustion environments have also been studied, from a thermal radiation perspective. The focus is on radiative property models that are useful specifically for engineering purposes. These property models are often developed from more advanced spectral models by means of correlative or other methods to simplify the treatment of the radiative transfer. One such model is the non-correlated statistical narrow band (SNB) model, which drops spectral relation between intensity and transmissivity, which is used in the correlated SNB model. By doing so a significant decrease in computational demand can be achieved. The accuracy of this model has been questioned in the literature although it has been suggested as an appropriate option for sooty environments. The assessment of the model revealed that it only gives good predictions in large geometries and highly sooty environments. Because of the model’s limited applicability and a still rather high computational demand it is not recommended for use even in sooty environments. A simpler model, and computationally much faster, called the weighted sum of gray gas (WSGG) model accompanied the assessment of the non-correlated SNB model. The WSGG model was shown to be a better choice than the non-correlated SNB model in sooty environments. A gray gas property model was compared with a WSGG model in combustion environments resembling the ones found in grate fired furnaces. In these environments, which also contains particles, the gray model was shown to give predictions of wall heat flux in close agreement with the WSGG model. This shows how the simplest model, which the gray model is, can sometimes be a suitable choice, especially when particles are present. Particle property models were evaluated in various combustion environments. A common approach is to use Planck mean coefficients to represent the particle properties. The use of Planck mean coefficients for fly-ash particles, common in furnaces combusting solid fuels, is shown to give large errors in prediction of both radiative heat flux and the source term in particular. The two investigated combustion environments are those found in grate fired furnaces and environments with high CO mole fraction. The grate fired furnace was studied in both modelling- and measurement work. Specifically the importance of particle radiation was investigated in the grate fired combustion environment. A preliminary study of the grate fired furnace was a parametric study. The parameters investigated were different particles originating from combustion of biomass and municipal solid waste, different furnace size, and boundary emissivities. The most significant effect on the overall radiative heat transfer is that of particles from municipal solid waste; moderate effects are seen when particles come from biomass. Increased furnace size most affected the heat flux to the hot bed and source term compared with a case without any particles. The choice of emissivity can be as important as considering particles or not. The measurement and modelling work were carried out on a 400 kW grate fired furnace combusting biomass. The boundary temperatures, flue gas temperature, gas mole fraction, particle mass-size distribution, and wall irradiation were measured. A so-called indirect wall irradiation was retrieved when the furnace was modelled with the implemented measured parameters. This indirect wall irradiation was compared with the directly measured wall irradiation. The study revealed that particle radiation is very important in the evaluated furnace, it doubles the wall irradiation in the hot flame zone compared with irradiation only from gases. The CO contribution to the total directional radiation was studied in environments with high mole fractions of CO, often found in gasifiers. CO is normally disregarded in environments where the fuel is fully oxidised, as it is a weak radiating species and small mole fractions of CO exist in these types of environments. The evaluation reveal that disregarding CO is still a good approach even in gasifier environments. These environments still contain small volume fractions of CO2 and H2O, which compared with CO are much stronger radiators. The rotational-vibrational bands of these two species overlaps the important fundamental band of CO reducing the importance of CO to the total directional radiative heat flux. Värmestrålning är högst relevant i förbränningsmiljöer. I dessa miljöer är förbränningsgaser och partiklar den huvudsakliga källan till värmestrålning. Förbränningsmiljön är komplex att beskriva. Analys av turbulenta flöden, kemiska reaktioner och transport av energi måste göras för att fullständigt beskriva miljön. Att kunna beskriva dessa fenomen är en viktig del i förståelsen av miljön men även för att kunna designa nya förbränningsmiljöer. Värmestrålning är en del av den energitransport som sker i förbränningsmiljön. Denna avhandling behandlar specifikt ett urval av de modeller som beskriver hur gaser och partiklar avger och tar upp värmestrålning, så kallade egenskapsmodeller. Två specifika förbränningsmiljöer har även studerats med avseende på värmestrålning, förbränningsmiljöer med hög andel kolmonoxid och de som existerar i rosterpannor. Vatten i gasform och koldioxid är de gaser som huvudsakligen inverkar på värmestrålningen men även andra gaser kan bidra, t ex metan och kolmonoxid. Sot är en partikel som förekommer i många förbränningsmiljöer. I de miljöer som eldar fasta bränslen, t ex biomassa, kol eller avfall, kan bränslepartiklar och aska även finnas. Resultaten från studier av egenskapsmodeller visar att då en viss andel partiklar finns i förbränningsmiljön så är det inte alltid motiverat att använda alltför avancerade egenskapsmodeller för gaserna. Enkla modeller kan prediktera likvärdiga resultat för värmestrålningen med avsevärt mindre behov av dataresurser. Detta beror på att partiklar börjar dominera upptagandet och avgivandet av värmestrålning jämfört med gaserna. Olika egenskapsmodeller för partiklar kan även påverka hur väl värmestrålningen predikteras. Väldigt ofta används enkla egenskapsmodeller för partiklar. För aska, kan dessa enkla egenskapsmodeller kan ge stora fel i uppskattningen av värmestrålningen. Resultaten från studier av egenskapsmodeller i denna avhandling guidar oss till några av de modeller som kan användas och vilka som skall undvikas. Kolmonoxid är en gas som har en mindre växelverkan med strålning än de två vanligaste gaserna, vatten och koldioxid. Av denna anledning så försummas oftast värmestrålningen från kolmonoxid. I förgasningsmiljöer kan volymandelen av kolmonoxid vara upp mot och över 50%. Detta är en väldigt hög andel jämfört med vanliga förbränningsmiljöer. Av denna anledning är det intressant att undersöka om kolmonoxid fortfarande går att bortse ifrån i förgasningsmiljöer, då värmestrålningen till väggarna avses. Denna avhandling visar att bidraget från kolmonoxiden fortfarande kan försummas i förgasningsmiljöer. Detta beror på att det oftast också finns små mängder av koldioxid och vatten vilka, på grund av dess starka strålningsegenskaper, överskuggar bidraget från kolmonoxiden. Den andra förbränningsmiljön som studerades var rosterpannan. Rosterpannan är en förbränningsteknologi som förbränner fasta bränslen. Förbränningen av bränslet startar längst ner i pannan på rostern och försätter ovan i förbränningsrummet av de brännbara gaser och partiklar som lämnar bränslebädden. I denna avhandling har fokus varit på värmestrålningen i förbränningsrummet. Både modelleringsstudier och experimentella studier har genomförts på olika rosterpannor. En första utredning av värmestrålning i rosterpannan var en parameterstudie. Parametrarna som studerades var partikelmängder från avfall och biomassa, storlekar på pannan och strålningsegenskaper för pannans ytor. Mest partiklar skapas vid förbränning av avfall så detta bränsle hade störst inverkan på värmestrålningen. Generellt ökade värmestrålningen till väggarna i pannan när storleken ökade. Valet av strålningsegenskaper för väggar och bädd visade sig ha stor inverkan på värmestrålningen. En 400 kW rosterpanna i pilotskala studerades genom att utföra mätningar och modellering. Mätningarna som utfördes på rosterpannan har inte tidigare utförts på någon rosterpanna. Uppmätt data användes som en input till modellering av pannan vilket möjliggjorde en djupare studie av värmestrålningen i pannan. Studien av pilotpannan visade att partiklar kan ha en stor inverkan på värmestrålningen till väggarna. Då partiklar betraktades så fördubblades värmestrålningen till väggarna i pannans nedre delar.

This report describe the wear of the protruding areas on the sides of the grate plates in the grate-kiln process in the hematite pellet production in LKAB, Kiruna. The steel plates are exposed to a hostile environment with heat cycles and corrosive atmosphere. An evaluation of the plates was made in co-operation with LKAB Metlab in Luleå and LKAB mechanical workshop in Kiruna. Instruments used are stereomicroscope, LOM, SEM, Spectroscope, Vickers Hardness and a surface nish meter. Results show the protruding areas of the plates are exposed to a tribochemical wear, where tops of the rough areas are torn down. A coating test is carried out at Tribolab, LTU in Luleå, using an SRV. Samples with a wear and corrosion resistant coating called Diamalloy 4276 abrade against eachother at high temperature and pressure. The coating do help to resist wear, but the environment of the test is to unrealistic to say by certain that it will help in the grate. A FEM-model in COMSOL Multiphysics 4.4 is made to calculate thermal stresses between coating and metal, the result show stresses up to 1 GPa will occur, this can be explain by the big dierence in thermal expansion coefficients of the materials. It will probably create cracks in the coating surface. Two solutions are presented, a coating is not recommended. The tribochemical wear is decreased by using a better surface nish. Therefore one can either machine the areas by drilling or milling, or one can change the casting method. Today sand casting is used, by using shell casting or precision casting, for example Shaw process, the surface nish is better over the whole plate, which also is better for corrosion resistance since less initiation points exist. Denna rapport presenterar en undersökning av slitaget på sidorna av grateplattor som används i gratekilnprocessen i hematitpelletstillverkningen på LKAB i Kiruna, även lösningar presenteras. Plattorna benner sig i en svår miljö med termiska cykler och korrosiva substanser. Utvärderingen av slitaget gjordes i samarbete med LKAB Metlab i Luleå och LKAB mekaniska verkstad i Kiruna. Utrustning som användes var Stereomikroskop, LOM, SEM, Spektroskop, Vickers hårdhetsmätare och ytnhetsmätare. Resultatet visar att sidorna av plattorna utsetts för ett tribokemiskt slitage där toppar av den grova utan slits ner. Ett ytbeläggningstest utfördes på Tribolab, LTU i Luleå, med en SRV. Prover med en beläggning har gnidits mot varandra under tryck och hög temperatur och jämförts med prover utan beläggning som utsattes för samma test. Ytbeläggningen som används står främst emot korrosion, men även slitage, den kallas Diamalloy 4276. Resultatet visar att beläggningen skyddar bra mot slitage, men miljön under testet var för orealistiskt för att med säkerhet kunna säga att det kommer hjälpa i graten. En FEM-modell gjordes med hjälp av COMSOL Multiphysics 4.4 för att beräkna de termiska spänningarna som uppstår mellan ytbeläggningen och metallen. Resultatet visar att spänningar på upp till 1 GPa kommer uppstå, detta kan förklaras med den stora skillnaden i termisk utvidgningskoecient mellan de två materialen. De höga spänningarna kan skapa sprickor i ytan. Två lösningar presenteras, en ytbeläggning rekommenderas inte i dagsläget. Det tribokemiska slitaget kan motverkas genom att förbättra ytnheten. Detta kan antingen utföras genom att bearbeta ytan, med fräsning eller slipning, eller att man byter gjutningsmetod. Idag används manuell formtillverkning, om man istället skulle använda skalformsgjutning eller precisionsgjutning, till exempel Shawprocessen, skulle man få en bättre ytnhet över hela plattan. Detta leder även till bättre korrosionsbeständighet då färre initieringspunkter nns.

Sulphur containing additives were used to destroy alkali chlorides in the furnace of a 100 kW grate reactor during combustion of a blend containing 40 ± 4% (based on energy content) corn stover with wood chips. Ferric sulphate spray, when added to zones where alkali chlorides have already been formed and gas temperature is < 1000 °C, can destroy a significant portion of alkali chlorides in the furnace even at dosage S/Cl = 0.4–0.6 and prevent high temperature chlorine corrosion of superheaters. This dosage can increase SO2 emissions from about 100 (without additives) to 250–350 mg/Nm³ 6% O2. Additive costs can be estimated at 0.4–1 €/MW h electricity with blends containing 40–100% corn stover, assuming a 30% efficiency in electricity production. Mixing ferric sulphate with fuel feed had little effectiveness compared to spraying it into the upper furnace. Elemental sulphur mixed with the fuel feed was much less effective than the ferric sulphate spray. The minimum dosage of elemental sulphur needed to prevent Cl deposition (S/Cl = 3) lead to high SO2 formation (≈2000 mg/Nm³ 6% O2).

Channelling is an undesirable phenomenon in the fixed-bed combustion of biomass. It is characterised by an uneven air distribution, and thus fuel conversion, throughout the fuel bed. Attempts to mitigate the channelling effect using redesigned grates have resulted in an increase in grate wear. Computational fluid dynamics can provide an insight into these issues. To this end, an unsteady, 2D numerical model for predicting solid fuel combustion under fixed-bed conditions is designed and developed. The commercial CFD code Fluent is used as the basis. The model is then validated using different existing data for ignition rates and species profiles through a biomass fuel bed. The model is applied to investigate factors that influence channelling in a randomly packed bed of biomass. These factors include: resistance to flow through the grate, the bed height, flue gas recirculation, and the initial moisture content of the fuel. A high value of grate resistance is confirmed as a key factor to reducing channelling. The 2D model is extended to three dimensions to capture 3D features within the fuel bed and grate. To reduce the simulation run times, the 3D model is parallelised to run on high performance computers or clusters. The complete 3D model is employed to examine measures to reduce grate wear. The influences of the shape of the grate, the inlet air flux, and the thickness of the ash layer are investigated. Results indicate that small passages are beneficial, but that low grate porosity and/or large spacing between passages may lead to excessive temperatures of the grate material or potentially carburising conditions at the surface of the grate.

Luossavaara-Kiirunavaara Aktiebolag (LKAB) är en gruvdriftskoncern med järnmalmsbrytning som huvudsaklig verksamhet. En av produkterna tas fram genom att raffinera järnmalm till pellets vilket är en efterfrågad produkt vid ståltillverkning. Vid sintring av råkulor till pellets är temperaturen väsentlig för att få så hög oxidation som möjligt av magnetit till hematit och för att få rätt fasthet. För att reglera värmen bör temperaturen mätas bland råkulorna eftersom det är kulornas temperatur som är det viktiga. Projektet går ut på att undersöka möjligheterna att mäta temperatur bland råkulor på gratevagnar som åker genom en pelletsugn med ett permanent mätsystem. Här ställs höga krav på mätsystemet på grund av miljö, portabilitet och drifttid. Miljöanalyser gjordes för att ta reda på vilken påfrestning ett mätsystem bör klara av. Förslag om placering av mätutrustning framtogs genom kartläggning av miljön. En värmeundersökning utfördes av vad hög värme har för påverkan på elektroniska komponenter som kan behövas till ett mätsystem. Det gjordes även en undersökning över vilka komponenter som kan klara av den värme ett mätsystem kan bli utsatt för. Utifrån detta kunde ett prototypmätsystem konstrueras för att mäta temperaturen där ett mätsystem kan placeras på en gratevagn samt för att skapa möjlighet för mätningar med termoelement i bädd. Mätsystemet skapades med trådlös kommunikation, möjlighet till loggning av data och med möjlighet att ansluta tre termoelement av typ S. Olika typer av trådlös kommunikation utvärderades för att se vad som kan vara mest lämpat med tanke på miljö, räckvidd, strålning och strömförbrukning. Strömförsörjning undersöktes för att hitta den mest lämpade strömförsörjningen med längst drifttid och högst funktionalitet. En utredning gjordes för att hitta monteringsmöjligheter av ett mätsystem på en gratevagn. Värmeavskärmning och isolering undersöktes för att få ner temperaturen i kapslingen och för elektroniken i ett mätsystem. Några olika temperaturgivare granskades för att hitta en som klarar av att mäta temperaturer upp till 1500°C och som fysiskt kan monteras på en gratevagn. Luossavaara-Kiirunavaara Aktiebolag (LKAB) is a mining group with iron ore mining as the main business. One of the products is produced by refining iron ore to iron pellets, which is a quality and environmentally clever product in steel production. When iron pellets are produced by roasting green pellets the temperature is very important. The goal is to get as much oxidation as possible from hematite to magnetite and to get correct mechanical properties. To control the process it’s important to know the temperature of the green pellets specifically and not the surrounding mechanical structure, ceramics lining in the furnace and the influence from radiation. The goal of the project is to examine possibilities to measure temperature with a permanent measurement system of green pellets which are transported on grate cars trough pellet plant. The measurement system has to meet some requirements of environment, portability and operating time. Analysis of the environment has been made to get specification of what a measurement system has to withstand. Proposition about assembly location has been investigated by analysis of the environment. A thermal analysis has been made of electronic components, especially electronic components that can be used in a measurement system. A analysis has also been made of which electronic components that are suited for a measurement system and can withstand the heat. A development measurement system has been developed from the results of the analysis. The system has been constructed to measure the temperature of what a system can be exposed of on a grate car. This with wireless and data-logging support and future measurements possibilities with three thermocouples of type S. Wireless data transfer was examined to see what type is most suited for the task with knowledge of environment, transmission range, radiation and power consumption. Power sources was examined to find a power source with longest working time and highest functionality. Heat insulation and reflective materials has been investigated with the goal to get the temperature in the system enclosure as low as possible. Some different types of temperature sensors that can measure temperatures up to 1500°C and which can be mounted on a grate car has been evaluated.

V magistrskem delu je poudarjeno določanje najprimernejše rešitve za odpadke, ki nastajajo pri proizvodnji higienskega papirja. Predstavljeno je stanje na področju ravnanja s stranskimi produkti pri proizvodnji higienskega papirja, mogoče rešitve problematike odpadkov v podjetju in izbira primernejše rešitve s pomočjo dveh primerjalnih metod. V nalogi je podrobno opisano stanje podjetja Paloma d.d. na področju odpadkov. Predstavljene so glavne vrste nastajajočih odpadkov, zakonski okviri, ki zadevajo ravnanje z njimi ter stroškovna analiza sedanjega stanja. Navedene so rešitve problematike, izmed katerih je po utemeljitvi izbrana najprimernejša. Kot rešitev problematike odpadkov v podjetju je predstavljena tehnologija sežiga. Opisane so razne vrste tehnologij sežiga odpadkov. Obravnavani sta tudi dve najnovejši tehnologiji, ki temeljita na vpeljavi električnih metod za obdelavo tovrstnega odpada. Navedene so dobre in slabe strani pri obdelavi naših odpadkov z vsako izmed obravnavanih tehnologij. Na podlagi teh informacij sta izbrani dve tehnologiji sežiga, ki sta najprimernejši za naš primer. Tako smo za primerjavo izbrali tehnologijo sežiga odpadkov na pomični rešetki in sežig odpadkov na lebdečem sloju. V ta namen sta se izvedla tudi poskusna sežiga naše vrste odpadkov na vsaki izmed omenjenih tehnologij. Pomemben prispevek naloge je na področju podrobne analize obeh tehnologij. Podatki so se črpali iz različnih literarnih virov, večinoma pa so izvlečeni iz referenčnih dokumentov najboljših razpoložljivih tehnik. Podatki so zbrani v pomembnejših dejavnikih, ki imajo poglaviten vpliv na področju tehnologije, ekologije in ekonomije posamezne tehnologije. Na tej podlagi se je izdelala primerjava med tehnologijama po dveh primerjalnih metodah. V ta namen so se zbrani in določeni dejavniki ocenili in primerjali med seboj. Rezultat je za posamezno tehnologijo številsko izražen in določa primerno rešitev. Cilj naloge, s strokovnimi argumenti ugotoviti, katera od tehnologij je po ekonomskih, tehnoloških in ekoloških parametrih najprimernejša, in hkrati izbrati najustreznejšo tehnologijo, je tako dosežen. The thesis stresses the determination of appropriate solution for handling with waste that results in the production process. The thesis presents the situation in the field of handling the toilet paper by-products, possible solutions of waste problems in the company and selection of more appropriate technological solution by means of two comparative methods. In the thesis is a detailed description of the waste problem situation in the company Paloma d.d.. Presented are the main kinds of waste, enforced law concerning handling with waste and a cost analysis of the present state. The solutions of the problems are stated and the most appropriate solution is chosen according to the facts. The technology of incineration is presented as the solution of waste problematic in the company. Described are various sorts of incineration technologies. Also two brand new technologies based on electrical methods are being discussed. Advantages and disadvantages of each described technology of waste treatment are being described. On the basis of this information two most appropriate technologies are chosen for our company. For comparison we took the incineration technology of waste on movable grate and incineration technology in fluidized bed. Two test incinerations of our waste products were made for each of the incineration technology. Important contribution of the work is made in the field of detailed analysis of both technologies. The information was extracted out of diversified literature but mostly from the best available techniques. The data is gathered in significant criterions which have essential influence in the fields of technology, economy and ecology. On this groundwork a quality comparison of two comparison methods was made between both technologies. For this purpose the collected criterions were estimated and compared between each other. The result is numerically expressed and defines an appropriate solution. The aim of this work, - to state with professional arguments which of the technologies is on the grounds of technological, economic and ecological parameters the most appropriate, - is achieved.

Validerat; 20101217 (root)

Several measuring campaigns with focus on deposition behavior have been conducted at full-scale power plants firing biomass in Denmark. These measuring campaigns have been reviewed in this work. The focus of the review is the obtained experiences on deposit formation, chemistry and shedding. Corresponding samples of fuels, ash deposits and fly ash have provided information on the transformation of inorganics in the boiler. Generally, grate fired boilers provide a fly ash containing high contents of K, Cl and S compared to the fuel ash, while suspension fired boilers fly ash has a composition nearly similar to the fuel ash. Inner most biomass deposits are always salt-rich, while thicker deposit layers also contain some Si and Ca. Deposit probe formation rate measurements have been performed in different ways on several boilers. Grate and suspension fired boilers seems to cause similar deposit formation rates. Suspension fired boilers generate more fly ash, while grate boilers form a fly ash with a higher fraction of melt formation (and thereby a higher sticking probability) at similar temperatures. For suspension fired units it is observed that wood with a lower ash content than straw gives rise to lower deposit formation rates. The flue gas temperature is an important parameter in the deposit behavior of biomass-fired boilers. Increases in the flue gas temperature of both grate and suspension fired boilers leads to increased deposition rates and deposits with higher contents of Si and Ca. This can be explained by increased deposition by inertial impaction due to higher melt fractions of ash particles (containing Si and Ca) at increased temperatures. The shedding behavior is influenced by exposure time, probe surface temperature, flue gas temperature and deposits chemistry. The influence of temperature on the degree of sintering varies with the fuel type. Possibly, increased contents of Si and Ca will lead to increases in the sintering temperature and thus to altered shedding behavior. It is recognized that the exposure time of the deposits in the flue gas influences the removability of the deposits.