Journal articles: 'Green pellets'

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Kumar, P. S., B. P. Ravi, O. Sivrikaya, and R. K. Nanda. "The study of pelletizing of mixed hematite and magnetite ores." Science of Sintering 51, no. 1 (2019): 27–38. http://dx.doi.org/10.2298/sos1901027k.

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The present study aims to investigate the use of mixed hematite and magnetite ores in iron ore pellet production. Pelletizing tests were carried out on the hematite and magnetite premixed pellet feed. Drop number and compressive strength tests for green and dry pellets; porosity, compressive strength and reducibility tests for fired pellets were carried out to determine the influence of mixing ratios of both iron oxides on those pellet properties. Experimental results showed that as the hematite content in the mix pellets is increased, the green drop number decreased from 6.5 to 5.2, the green compressive strength decreased from 1.51 to 1.28 kg/pellet and the dry compressive strength decreased from 2.50 to 1.60 kg/pellet. It was determined that fired compressive strength of mix pellets decreased from 380 to 230 kg/pellet when the hematite content in the mixed pellet is increased. The reducibility of mix pellets had almost the same trend and it was faster up to 40 min reduction time. The results showed that the use of hematite together with magnetite is possible to produce pellets with sufficiently good quality in terms of wet, dry and fired mechanical strengths. The porosity and reducibility values of mix pellets were also found to be adequate to use as feed for the blast furnace.

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Kusumoputro, Benyamin, Rozandi Prarizky, Wahidin Wahab, Dede Sutarya, and Li Na. "Assesment of Quality Classification of Green Pellets for Nuclear Power Plants Using Improved Levenberg-Marquardt Algorithm." Advanced Materials Research 608-609 (December 2012): 825–34. http://dx.doi.org/10.4028/www.scientific.net/amr.608-609.825.

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Cylindrical uranium dioxide pellets, which are the main components for nuclear fuel elements in Light Water Reactor, should have a high density profile, uniform shape and quality for the safety used as a reactor fuel component. The quality of green pellets is conventionally monitored through a laboratory measurement of the physical pellets characteristics followed by a graphical chart classification technique. However, this conventional classification method shows some drawbacks, such as the difficulties on its usage, low accuracy and time consuming, and does not have the ability to adress the non-linearity and the complexity of the relationship between the pellet’s quality variables and the pellett’s quality. In this paper, an Improved Levenberg-Marquard based neural networks is used to classify the quality process of the green pellets. Robustness of this learning algorithm is evaluated by comparing its recognition rate to that of the conventional Back Propagation neural learning algorithm. Results show that the Improved Levenberg-Marquard algorithm outperformed the Back Propagation learning algorthm for various percentage of training/testing paradigm, showing that this system could be applied effectively for classification of pellet quality.

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Umadevi, Tekkalakote, Komala Shivanna Sridhara, Munukuntla Raju, Maribasappanavar Basavaraja, Desai Sanghamesh, Sah Rameshwar, and Lokendraraj Singh. "Effect of multi-layer feeding of sized green pelletson bed permeability, structure and properties of fired pellets in straight grate induration furnace." Metallurgical Research & Technology 118, no. 5 (2021): 503. http://dx.doi.org/10.1051/metal/2021061.

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Green pellets while indurating in a straight grate induration furnace, pass through different thermal treatments, namely drying, preheating, heating and cooling. The firing of the pellet bed is downdraft using Corex gas and cooling is updraft using ambient air. Coke breeze is used as solid fuel to supplies the necessary heat for uniform heating of the pellet. The physicochemical conditions prevailing in the indurating furnace, i.e., feeding rate, bed height, pellet size, position of the pellets in the bed, temperature, partial pressure of oxygen, amount of fuel, etc. have bearings on the phases and structures of the fired pellets across the core to the shell. The time difference between the reduction and oxidation of the pellet depends on the size of the pellet as well as position of the pellet in the bed. The pellet size as well as the position of the pellet in the furnace has a marked effect on the formation of different phases and microstructure. Usually, mixed pellets of different sizes varying from 8 to 16 mm pellets are fired in duration furnace. The study was aimed at to optimize the pellet bed with different size range of pellets put in layers to make uniform firing and cooling of the pellets throughout the bed to achieve desired micro-structure and properties. The green pellets were divided into three sizes as A − coarse (–16 + 12.5 mm), B − medium (–12.5+10 mm) and C − small (–10 + 8 mm). The bed permeability of pellet plant induration furnace was 91.7JPU (Japanese Permeability Unit). Except permeability of pellet bed with single layer of smaller size pellets (C-C-C), the bed permeability with three layers, two layers & single layer of different size pellets was similar or greater than the bed permeability of pellet plant. From the results of basket trials conducted at pellet plant, it was found that the layer wise pellets like B-A-C, CA-B, AB-C and B-B-B resulted in higher Tumbler Index (TI) and Cold Crushing Strength (CCS) compared to other different size pellets as layer due to better slag bonding and lower pellet porosity. These pellets were exposed to optimum firing temperature as well as the cooling process with the presence of sufficient oxygen for the conversion of magnetite to hematite.

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Sutarya, Dede, and Benyamin Kusumoputro. "Classification of UO₂ Green Pellet Quality Using Intelligent Techniques." Advanced Materials Research 557-559 (July 2012): 2054–64. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.2054.

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Abstract. Modern production facilities are large and highly complex, and they operate with numerous variables under closed loop control. In the production of green uranium pellets, pellet quality control involves many variables. Therefore, the classification of the quality of pellets is important for improving the efficiency of the production process. Classification of pellet quality using the conventional graphical method has some drawbacks; for example, the scale of the graph affects the accuracy and ease of use. In this paper, intelligent techniques are used to classify the quality of the pressurized water reactors(PWRs) green pellets into three categories according to the guidelines in the quality control manual of the experimental fuel elements laboratory of BATAN. Four features are used for classification, namely, height, volume, weight, density and theoretical density of the pellets. A dataset (150 observations) was collected from one lot of compacted UO2 pellets and was used for training and testing of an ANFIS model. Up to 86.27% of the data can be classified correctly using the ANFIS model. Such performance is comparable to that of artificial neural networks. Thus, this model can be applied effectively for the evaluation and classification of pellet quality.

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Bhuiyan, Iftekhar U., Johanne Mouzon, Birgit Schröppel, Andres Kaech, Illia Dobryden, Seija P. E. Forsmo, and Jonas Hedlund. "Microstructure of Bentonite in Iron Ore Green Pellets." Microscopy and Microanalysis 20, no. 1 (January 7, 2014): 33–41. http://dx.doi.org/10.1017/s1431927613013950.

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AbstractSodium-activated calcium bentonite is used as a binder in iron ore pellets and is known to increase strength of both wet and dry iron ore green pellets. In this article, the microstructure of bentonite in magnetite pellets is revealed for the first time using scanning electron microscopy. The microstructure of bentonite in wet and dry iron ore pellets, as well as in distilled water, was imaged by various imaging techniques (e.g., imaging at low voltage with monochromatic and decelerated beam or low loss backscattered electrons) and cryogenic methods (i.e., high pressure freezing and plunge freezing in liquid ethane). In wet iron ore green pellets, clay tactoids (stacks of parallel primary clay platelets) were very well dispersed and formed a voluminous network occupying the space available between mineral particles. When the pellet was dried, bentonite was drawn to the contact points between the particles and formed solid bridges, which impart strength to the solid compact.

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Liu, Hao, Shihong Peng, Ke Zhang, Yuelin Qin, Fei Meng, Wenchao He, Weiqiang Liu, Min Chen, and Lixiang Yan. "Effect of Finely Ground Limestone and Dolomite on Compression Strength and Reduction Swelling of Vanadium-Titanium Pellets." Materials 14, no. 16 (August 7, 2021): 4433. http://dx.doi.org/10.3390/ma14164433.

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Vanadium−titanium magnetite (VTM) is an important raw material for ironmaking under the situation of increasingly demanding scarce resources. To further improve the metallurgical properties of pellets, and to satisfy the requirements of blast furnace slag basicity, finely ground dolomite and limestone have been added to the pellet. In this study, the effect of finely ground dolomite and limestone on the metallurgical properties (green pellet drop strength, cold compression strength, reduction swelling index, and microscopic mineral structure) of VTM pellets were investigated. With the addition of finely ground dolomite and limestone, the drop strength of the green pellet was improved. The effect of adding finely ground limestone was greater than adding finely ground dolomite. Adding more finely ground dolomite and limestone compared to pellets without limestone and dolomite, the cold compression strength was decreased, which was attributed to the decomposition of limestone and dolomite during the induration of pellets. With the addition of dolomite, the reduction swelling index (RSI) increased firstly and then decreased. When the basicity of the pellet was 0.54 to 0.94, the slag phase with the lowest melting point was formed, corresponding to the maximum of the reduction swelling index. For the pellets with added limestone, the reduction swelling of the pellets deteriorated. The reduction index of the pellets increased and reached the maximum (26.6%) at a basicity of 1.54, which belongs to abnormal swelling.

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Meng, Qing-min, Jia-xin Li, Tie-jun Chun, Xiao-feng He, Ru-fei Wei, Ping Wang, and Hong-ming Long. "Effects of Treated Cow Dung Addition on the Strength of Carbon-Bearing Iron Ore Pellets." Advances in Materials Science and Engineering 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/1019438.

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It is of particular interest to use biomass as an alternative source of fuel in direct-reduction ironmaking to ease the current reliance on fossil fuel energy. The influence of cow dung addition on the strength of carbon-bearing iron ore pellets composed of cow dung, iron ore, anthracite, and bentonite was investigated, the quality of green and dry pellet was evaluated based on FTIR analysis, and the mechanism of strength variation of the reduced pellets was investigated by analysing the phase composition and microstructure using XRD and SEM. The results show that cow dung addition decreased the green pellet strength due to expansion of the amorphous region of the cellulose in the cow dung; however, the dry pellet strength increased substantially. In the process of reduction roasting, it was found that cow dung addition can promote aggregation of iron crystals and increase the density of the pellets, resulting in increased strength of the reduction roasted pellets, while excessive cow dung addition resulted in lower strength.

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Jovanovic, Vladimir, Dinko Knezevic, Zivko Sekulic, Milan Kragovic, Jovica Stojanovic, Slavica Mihajlovic, Dragana Nisic, Dragan Radulovic, Branislav Ivosevic, and Milan Petrov. "Effects of bentonite binder dosage on the properties of green limestone pellets." Chemical Industry 71, no. 2 (2017): 135–44. http://dx.doi.org/10.2298/hemind160210023j.

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This paper presents the results of tests carried out to determine how the dosage of bentonite added as binder, affects the properties of green pellets made of the limestone fines that originate from Lithothamnium limestone processing. Bentonite was added to limestone in different mass fractions (1, 2.5, 5 and 10%), whereas all the other parameters of the pelletizing process remained constant. The aim of pelletizing was to consolidate limestone fines and form mechanically stable pellets, provided that all the other properties of limestone remain unchanged. The pellets formed in this way were analysed applying DTA/TG analysis and FTIR and SEM analyses. The results showed uniform distribution of bentonite in the pellets, demonstrated that the pellets are compact and there is no formation of new compounds. The pellets were tested for resistance to impact, compressive strength and abrasion resistance. Also disintegration tests were performed to determine the time required for the pellet to disintegrate completely in water. These mechanical properties are essential for transport, handling, storage and general use of pellets. The values of most of the parameters established for pellets with 5% bentonite, meet the standards required for use in agriculture for liming acid soils, however their application is limited because their impact resistance is unsatisfactory and the time required for their complete disintegration in water is extremely short. It should be noted that further increase of bentonite content (over 10%) will not improve the quality of green pellets. In view of the results obtained, it is necessary to introduce drying into the pelletizing process in order to bring the green pellets into solid state.

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Kusumoputro, Benyamin, Dede Sutarya, and Li Na. "Nuclear Power Plant Fuel’s Quality Classification Using Ensemble Back Propagation Neural Networks." Advanced Materials Research 685 (April 2013): 367–71. http://dx.doi.org/10.4028/www.scientific.net/amr.685.367.

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Nuclear power plants fuel production is very crucial and highly complex processes, involving numerous variables. For the safety used in the Light Water Nuclear Reactor, the cylindrical uranium dioxide pellets as the main fuel element should shows uniform shape, uniform quality and a high density profile. Therefore, the assesment of the quality classification of these pellets is important for improving the efficiency of the production process. The quality of green pellets is conventionally monitored through a laboratory measurement of the physical pellets characteristics followed by a graphical chart classification technique. This method, however, is difficult to use and shows low accuracy and time consuming, since its lack of the ability to adress the non-linearity and the complexity of the relationship between the pellet’s quality variables and the pellett’s quality. In this paper, an intelligent technique is develop to classify the pellets quality by using a computational intelligence methods. Instead of a Single Back Propagation neural networks that ussualy used, an Ensemble Back Propagation neural networks is proposed. It is proved in the experimental results that the Ensemble Back Propagation neural networks show higher classification rate compare with that of Single Back Propagation neural networks, showing that this system could be applied effectively for classification of pellet quality in its fabrication process.

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Frodeson, Stefan, Pär Lindén, Gunnar Henriksson, and Jonas Berghel. "Compression of Biomass Substances—A Study on Springback Effects and Color Formation in Pellet Manufacture." Applied Sciences 9, no. 20 (October 14, 2019): 4302. http://dx.doi.org/10.3390/app9204302.

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In order to increase the use of a variated raw material base for pellet production with a maintained density level, knowledge of the biomaterials’ ability to counteract any springback effects is essential. In this study, the springback effects were investigated for single press produced pellets from cellulose, hemicelluloses, pectin, and two woods at different moisture contents. The change in pellet coloring was also tested through a spectrophotometer for both xylan and carboxymethyl cellulose (CMC) pellets. The results show that the density of xylan pellets is much higher than glucomannan, for both green and cured pellets, and that the length of the pellets, as well as springback contribution, differ between the hemicelluloses. The study also presents results showing that both xylan and CMC pellets have a mutually identical spectrum and that the changes in the structure of xylan are not only related to moisture content, but are also pressure-related. The study also postulates that the color difference of the xylan pellets is a result of physical changes in the structure, as opposed to being of a chemical nature.

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Thiffault, Barrette, Blanchet, Nguyen, and Adjalle. "Optimizing Quality of Wood Pellets Made of Hardwood Processing Residues." Forests 10, no. 7 (July 23, 2019): 607. http://dx.doi.org/10.3390/f10070607.

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Small-scale wood pellet producers often use a trial-and-error approach for determining adequate blending of available wood processing residues and pelletizing parameters. Developing general guidelines for optimizing wood pellet quality and meeting market standards would facilitate their market entry and profitability. Four types of hardwood residues, including green wood chips, dry shavings, and solid and engineered wood sawdust, were investigated to determine the optimum blends of feedstocks and pelletizing conditions to produce pellets with low friction force, high density and high mechanical strength. The feedstock properties reported in this study included particle size distribution, wood moisture content, bulk density, ash content, calorific values, hemicelluloses, lignin, cellulose, extractives, ash major and minor elements, and carbon, nitrogen, and sulfur. All residues tested could potentially be used for wood pellet production. However, high concentrations of metals, such as aluminum, could restrict their use for accessing markets for high-quality pellets. Feedstock moisture content and composition (controlled by the proportions of the various residue sources within blends) were the most important parameters that determined pellet quality, with pelletizing process parameters having less overall influence. Residue blends with a moisture content of 9%–13.5% (dry basis), composed of 25%–50% of sawdust generated by sawing of wood pieces and a portion of green chips generated by trimming of green wood, when combined with a compressive force of 2000 N or more during pelletizing, provided optimum results in terms of minimizing friction and increasing pellet density and mechanical strength. Developing formal relationships between the type of process that generates residues, the properties of residues hence generated, and the quality of wood pellets can contribute to optimize pellet production methods.

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Liu, Hao, Ke Zhang, Henrik Saxén, Weiqiang Liu, Yuelin Qin, and Xiaoyan Xiang. "Experimental Study of the Effect of B2O3 on Vanadium-Titanium Magnetite Concentrates Pellets." Journal of Chemistry 2020 (August 27, 2020): 1–11. http://dx.doi.org/10.1155/2020/9768795.

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This paper aims to improve the metallurgical properties of vanadium-titanium magnetite (VTM) concentrates pellets by applying solid waste containing B2O3. Thus, the effects of adding B2O3 on the drop strength, compressive strength, pores area ratio, high-temperature metallurgical properties, and microstructure of VTM pellets were studied through pelletizing and roasting experiments. Results show that the addition of B2O3 reagent is not conducive to the increase of the drop strength of the green pellets. Nevertheless, the compressive strength and fracture toughness of the roasted pellets can be improved by adding more B2O3 during the pelletizing. The reduction degree of VTM pellets is firstly decreased and then increased with the added B2O3 amount. It is possible to improve the compaction degree and restrain the reduction-pulverization degree of the pellet by a low amount of additive (B2O3). The reduction-expansion performance of VTM pellets, in turn, can be raised by adding B2O3.

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Oppel, Steffen, Jennifer L. Lavers, Alexander L. Bond, and Gavin Harrison. "Reducing the primary exposure risk of Henderson crakes (Zapornia atra) during aerial broadcast eradication by selecting appropriate bait colour." Wildlife Research 43, no. 4 (2016): 298. http://dx.doi.org/10.1071/wr15198.

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Context Operations to eradicate non-native invasive predators from islands frequently put native species at risk of consuming harmful substances, such as poison bait. The incorporation of certain colours in poison-bait pellets may reduce the risk of bait consumption and, therefore, non-target mortality. Previous work indicated that birds generally avoid blue or green colours; however, there is substantial inter-specific variation in this preference, and more experimental work on species of conservation concern is needed. Aims We tested whether a globally threatened island endemic, the Henderson crake (Zapornia atra), which suffered substantial mortality during a rat-eradication attempt on Henderson Island in 2011, would consume fewer blue than green pellets, which were used during the previous eradication attempt. Methods We held 22 Henderson crakes in captivity and provided them with either blue or green non-toxic pellets for 5 days in June and July 2015. We measured consumption and used linear mixed models to evaluate whether bait colour influenced consumption. Key results Henderson crakes did not consume any dry pellets, and all trials were conducted with wet bait pellets. We found slightly lower consumption of blue pellets than green pellets, and substantial variation among individuals. Females (n = 17) consumed 24% less blue than green bait, whereas males (n = 5) consumed 77% less blue than green bait. Conclusion Henderson crakes are unlikely to consume dry pellets, and will likely consume fewer blue than green bait pellets. Implications We recommend that any future rat eradication on Henderson Island considers using blue rather than green baits and targets dry weather to reduce the risk of Henderson crakes consuming toxic rodenticide bait pellets.

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Kiss, Imre, and Vasile Alexa. "Short introspections regarding the sawdust briquetting as sustainable solution for the environment." Analecta Technica Szegedinensia 8, no. 2 (May 12, 2014): 72–79. http://dx.doi.org/10.14232/analecta.2014.2.72-79.

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Wood pellets have only become an important part of this boom in the past few years. Owners of large coal-fired power stations in Europe started searching for a way to fulfill the new regulations and to find a solution for the declining economic relevance of traditional coal-fired power stations due to their high carbon dioxide emissions. The answer was to give the old dirty giants a green coat of paint by “co-firing” regular coal power plants with wood pellets. Wood pellets have similar burning qualities to traditional coal and the costs of converting boilers to burn wood pellets are low. The idea of declaring wood pellets as a carbon neutral energy source was based on the assumption that the released emissions of carbon dioxide during the burning process are neutralized by the carbon that is captured and stored in newly growing trees. The idea of using wood as a renewable source was backed by environment organizations. More recent pellet investment projects as well as facilities currently under construction show that the production of wood pellets is being outsourced by the energy firms to companies specialized in wood pellet production. These firms are 100-percent focused on sourcing the raw material, operating the wood pellet production plant and handling the logistics for transporting the renewable resource.

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Tavares, Luís Marcelo, and Rafaella F. de Almeida. "Breakage of green iron ore pellets." Powder Technology 366 (April 2020): 497–507. http://dx.doi.org/10.1016/j.powtec.2020.02.074.

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Schlesinger, William H. "Are wood pellets a green fuel?" Science 359, no. 6382 (March 22, 2018): 1328–29. http://dx.doi.org/10.1126/science.aat2305.

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Kostomitsopoulou Marketou, Ariadne, Fabrizio Andriulo, Calin Steindal, and Søren Handberg. "Egyptian Blue Pellets from the First Century BCE Workshop of Kos (Greece): Microanalytical Investigation by Optical Microscopy, Scanning Electron Microscopy-X-ray Energy Dispersive Spectroscopy and Micro-Raman Spectroscopy." Minerals 10, no. 12 (November 27, 2020): 1063. http://dx.doi.org/10.3390/min10121063.

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This paper aims to expand our understanding of the processes involved in the production of the artificial pigment Egyptian blue through the scientific examination of pigments found in the first century BCE workshop of the Greek island of Kos. There, 136 Egyptian blue pellets were brought to light, including successfully produced pellets, as well as partially successful and unsuccessful products. This study is based on the examination of eighteen samples obtained from pellets of various textures and tones of blue, including light and dark blue pigments, coarse and fine-grained materials, and one unsuccessful pellet of dark green/grey colour. The samples were examined by optical microscopy, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS), and micro-Raman spectroscopy. These complementary microanalytical techniques provide localised information about the chemical and mineralogical composition of this multicomponent material, at a single-grain level. The results shed light on the firing procedure and indicate possible sources for raw materials (beach sand, copper alloys), as well as demonstrating the use of a low-alkali starting mixture. Moreover, two different process for the production of light blue pigments were identified: (a) decreased firing time and (b) grinding of the initially produced pellet and mixing with cobalt-containing material.

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Jeon, Sang-Chae, Jae-Won Lee, Ju-Ho Lee, Sang-Jun Kang, Kwang-Yun Lee, Yung-Zun Cho, Do-Hee Ahn, and Kee-Chan Song. "Fabrication of UO2Porous Pellets on a Scale of 30 kg-U/Batch at the PRIDE Facility." Advances in Materials Science and Engineering 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/376173.

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In the pyroprocess integrated inactive demonstration (PRIDE) facility at the Korea Atomic Energy Research Institute (KAERI), UO2porous pellets were fabricated as a feed material for electrolytic reduction on an engineering scale of 30 kg-U/batch. To increase the batch size, we designed and modified the corresponding equipment for unit processes based on ceramic processing. In the course of pellet fabrication, the correlation between the green density and sintered density was investigated within a compaction pressure range of 106–206 MPa, in terms of the optimization of processing parameters. Analysis of the microstructures of the produced UO2porous pellets suggested that the pellets were suitable for feed material in the subsequent electrolytic reduction process in pyroprocessing. This research puts forth modifications to the process and equipment to allow the safe mass production of UO2porous pellets; we believe these results will have immense practical interest.

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Shi, Yan, Xiao Jun Li, and Chang Qing Hu. "Influence of Temperature on Carbonation Pellet for Ferrous Dust." Advanced Materials Research 690-693 (May 2013): 374–77. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.374.

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In a certain reaction time, CO2 concentration and flow rate, the carbonation experiment was carried out about green pellets prepared by the ferrous dust and active lime with 15%, 20%, 25%, 30% CaO content ratio respectively. The conversion ratio, porosity and compressive strength of carbonation pellets were analyzed at 200°C, 400°C, 600°C, 800°C.The results show that, with the reaction temperature increasing, CaO conversion ratio of carbonation reaction and the compressive strength increased, and the porosity decreased significantly; when the reaction temperature is 800°C, the CaO conversion ratio of reaction with 25% CaO content pellet can reach 47.26%, these can make the carbonation pellet to achieve a better carbonation degree and quality.

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S. Medina, Midilane, Sabrina G. M. Carvalho, Eliana N. S. Muccillo, and Reginaldo Muccillo. "Enhancement of the Ionic Conductivity in Electric Field-Assisted Pressureless Sintered BITIVOX Solid Electrolytes." Ceramics 2, no. 3 (August 11, 2019): 502–13. http://dx.doi.org/10.3390/ceramics2030038.

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Bi4V1.8Ti0.2O11 (BITIVOX) ceramic pellets, prepared with powders obtained by a sol gel technique, were sintered either conventionally at 800 °C/8 h or by applying an AC electric voltage, limiting the electric current through the pellets. Electric voltages were applied isothermally at 700 °C and 800 °C during 5 min in the green pellet positioned in the sample holder of a dilatometer for monitoring thickness variation. The BITIVOX pellets shrank 13.6% after applying 200 V cm−1 at 800 °C and 10.4% heating to 800 °C for 8 h. Thermal analysis and X-ray diffraction of the powders were performed to evaluate the crystallization temperature and the structural phase, respectively. The electrical behavior of the sintered BITIVOX pellets was analyzed by the impedance spectroscopy technique, showing that the sample flash sintered at 800 °C/5 min had lower bulk resistivity than the sample conventionally sintered at 800 °C/8 h. The surfaces of the sintered pellets were observed in a scanning electron microscope showing similar grain sizes and pore content in all sintered samples.

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Ling, Chuo Ann, Shahrom Mahmud, and Siti Khadijah Mohd Bakhori. "Effects of Annealing Treatment on Photoluminescence and Structural Properties of ZnO Nanostructures." Advanced Materials Research 501 (April 2012): 184–88. http://dx.doi.org/10.4028/www.scientific.net/amr.501.184.

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Zinc oxide (ZnO) pellets were prepared by agglomeration of ZnO nanopowder with distilled water in this study. Annealing at 800oC in different ambient was done on the surface of the pellets in order to change the photoluminescence and structural properties of the sample. The ZnO pellets that were annealed in air, oxygen and nitrogen ambient reduce the intensity of near-band-edge emission in photoluminescence spectra. The observed change in green luminescence after the annealing process suggests that the oxygen vacancies are the recombination centers for green luminescence in the samples. Red luminescence was also observed and it is attributed to oxygen vacancies in different energy level. Different annealing ambient had significantly modified the green and red luminescence. Structural investigation carried out by X-ray diffraction (XRD) revealed the polycrystalline nature for ZnO pellets with hexagonal phase and annealing process increased the cystallinity of the ZnO pellets.

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Barbu, Aurica, and Mihai Ovidiu Cojocaru. "The Sintering Mixed Powders Behavior of Triuranium Octoxide in Uranium Dioxide." Advanced Materials Research 1114 (July 2015): 22–28. http://dx.doi.org/10.4028/www.scientific.net/amr.1114.22.

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The main aim of this research was to study the sintering behavior in hydrogen atmosphere of mixed powders of triuranium octoxide (U3O8) powder in dioxide uranium (UO2) powders. By cold pressing the green pellets of mixed powders of triuranium octoxide in hyper stoichiometric uranium dioxide has density over 40 % UO2 theoretical density (TD). The sintered pellets had a height diameter ratio (H / D) over one and oxygen uranium ratio (O/U) near stoichiometry of uranium dioxide (UO2). The densities of sintered pellets were up to 97% of uranium dioxide theoretical density. The proposed treatment of sintering are function of green pellets density. Increasing the proportion of triuranium octoxide leads to a decrease in the density of the sinter pellets. The pellets made by 100 % of triuranium octoxide not resist to proposed sintering treatment. The metallographic analysis show uniform grains for sinter pellets made by the 30 % mixture of triuranium octoxide in uranium dioxide. This UO2 sinter pellets are without surface defects.

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Xing, Zhenxing, Gongjin Cheng, Zixian Gao, He Yang, and Xiangxin Xue. "Effect of Incremental Utilization of Unground Sea Sand Ore on the Consolidation and Reduction Behavior of Vanadia–Titania Magnetite Pellets." Metals 11, no. 2 (February 5, 2021): 269. http://dx.doi.org/10.3390/met11020269.

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In the iron and steel industry, improving the usage amount of New Zealand sea sand ore as a raw material for ironmaking can reduce the production costs of iron and steel enterprises to a certain extent. In this paper, New Zealand sea sand ore without any grinding pretreatment was used as a raw material, oxidized pellets were prepared by using a disc pelletizer, and the effect of sea sand ore on the performance of green pellets and the metallurgical properties of oxidized pellets was investigated. The effects of sea sand ore on the compressive strength, falling strength, compressive strength of oxidized pellets, and reduction performance were mainly investigated. X-Ray Diffraction (XRD) patterns and Scanning Electron Microscope (SEM) analysis methods were used to discuss the influence of sea sand ore on the microstructure of the pellets’ oxidation and reduction process. As the amount of sea sand ore used increased, the compressive strength of green pellets was gradually decreased, and the falling strength of green pellets and the compressive strength of oxidized pellets were gradually increased. When the amount of sea sand ore used was 40%, the reduction swelling index of pellets was 16.31%. The increase of sea sand ore used made the reduction of pellets suppressed and the reduction rate decreased. When the amount of sea sand ore used increased to 40%, the reduction degree of sea sand ore pellets was only 60.06%. The experimental results in this paper provide specific experimental data for the large-scale application of New Zealand sea sand ore in the blast furnace ironmaking process.

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Espuelas, Sandra, Sara Marcelino-Sádaba, Jesus Maria del Castillo, Benat Garcia, and Andres Seco. "Valorization of Insulation Cellulose Waste as Solid Biomass Fuel." Applied Sciences 11, no. 17 (September 4, 2021): 8223. http://dx.doi.org/10.3390/app11178223.

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This paper investigates the ability of insulation cellulose fiber powder (CFP) to be pelletized for its valorization as biomass fuel. CFP is a waste originating from insulation cellulose manufacturing that lacks any method of valorization because of its boron salts content. A sugar byproduct and lignosulfonate (LS) were considered as binders for the pellet manufacturing process. Physical tests were carried out to characterize the pellets’ performance. Chemical and combustion tests were considered to state the pellets’ potential as a green energy source. Raw CFP showed good ability in its pelletization and durability in the range of 15–30% of moisture content. The pellet’s density decreased as water content increased. Binders increased the pellet’s length before and after the durability test. Binders also increased the CFP pellet’s water absorption, demonstrating a potential decrease in durability against environmental factors. Binders also decreased the lower heating value. Ultimate analysis showed a slight Nitrogen increase in both binder combinations that could potentially raise the pollutant NOx combustion emissions. All the combinations showed adequate combustion characteristics, but binders increased ash production. Additives decreased the CFP volatile matter content and increased the fixed carbon, which could facilitate a more stable combustion. DTA curves showed a mass loss rate decrease in the volatile stage for the binder combinations, which also could be considered as an indicator of a more stable combustion. The ashes’ chemical compositions when analyzed by XPS showed boron contents oscillating between 10.03% and 16.42%, demonstrating the possibility of recovering them from the combustion ashes.

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Stollenwerk, Manfred, Tobias Schäfer, Johannes Stadtmüller, Thorsten Döhring, Dominic Freudenmann, and Nicole Röcke. "Sputtered highly effective iridium catalysts: a new approach for green satellite propulsion." Journal of Materials Science 56, no. 16 (March 1, 2021): 9974–84. http://dx.doi.org/10.1007/s10853-021-05897-z.

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AbstractThis work demonstrated the large potential of sputtered iridium metal for catalytic reactions shown by the example of decomposition of hydrogen peroxide (H2O2) for space propulsion systems. For this purpose, iridium was coated onto Al2O3 pellets by a sputter process under varied process parameters. Depending on previously selected parameters, the obtained metal-loaded pellets offer closed- and/or open-shell structures. Catalytic productivity of these first-generation iridium-sputtered catalysts was estimated in laboratory experiments and compared to platinum-loaded pellets. Under optimized sputter-process conditions, the reactivity is significantly improved compared to the platinum-impregnated pellets. The better catalytic productivity can be explained by the increased active surface area of the iridium layers on the pellets. The surface morphology and the microstructure of the iridium coating can be actively controlled by the sputter pressure. The results are in accordance with the sputtering process pressure tendency described by the Thornton Structure–Zone Model. Graphical abstract

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Wang, Shuai, Yufeng Guo, Kuo Liu, Zhuang Yang, Yajing Liu, Ying Jiang, Feng Chen, Fuqiang Zheng, and Lingzhi Yang. "The Deposit Formation Mechanism in Coal-Fired Rotary Kiln for Iron Ore Pellet Production: A Review." Crystals 11, no. 8 (August 17, 2021): 974. http://dx.doi.org/10.3390/cryst11080974.

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The deposit-forming problem is one of the main bottlenecks restricting the yield and production benefit of iron ore pellets produced by coal-fired rotary kilns. In order to implement measures to ensure the efficient production of pellets by coal-fired rotary kilns, the mechanism and influencing factors on the deposit formation were reviewed. The pellet powder and coal ash come together to form the material base of the deposit. Meanwhile, the local reducing atmosphere caused by the continued combustion of residual carbon increases the FeO content, resulting in the formation of low-melting-point silicates. Moreover, alkali metal elements in coal ash can also promote liquid phase formation to cause serious deposit aggregation problems. During high-temperature roasting, the liquid phase corrodes the surface of the refractory brick to form the initial deposit, whereafter, it binds the pellet powder and coal ash from the material layer, which causes the deposit to accumulate continuously. The deposit formation of coal-fired rotary kilns is the result of interaction between many factors, which includes the quality of the green pellets, the composition of coal ash, the combustion efficiency of pulverized coal, roasting temperature, FeO content and alkali metal input. Finally, it is recommended that some measures to mitigate deposit formation can be adopted, such as increasing the compression strength of preheated pellets, choosing high-quality raw materials with low alkali metals, improving the combustion of pulverized coal.

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Chen, Xi, Wenqi Zhong, Tiancai Wang, Fei Liu, and Zhi Zhang. "Genetic Optimization of Energy Consumption of Pellet Shaft Furnace Combustor Based on Support Vector Machine (SVM)." International Journal of Chemical Reactor Engineering 12, no. 1 (January 1, 2014): 205–14. http://dx.doi.org/10.1515/ijcre-2013-0117.

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Abstract Investigation on optimization of pellet shaft furnace based on the combination of genetic algorithm and support vector machine (SVM) is carried out. A SVM classifier model is developed to map the complex nonlinear relationship between operating parameters and the quality indexes of fired pellet, and a genetic algorithm is adapted in the energy optimization with the fitness function based on the SVM classifier model. This method can reduce the energy consumption while maintaining the fired pellet quality stable. The results show that the accuracy of the SVM classifier model is satisfied and the gas consumption can be reduced by 4% per ton of green pellets with this optimization method.

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Cheng, Gong-jin, Zhen-xing Xing, He Yang, and Xiang-xin Xue. "Effects of High Proportion Unground Sea Sand Ore on the Preparation Process and Reduction Performance of Oxidized Pellets." Minerals 11, no. 1 (January 18, 2021): 87. http://dx.doi.org/10.3390/min11010087.

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The New Zealand sea sand ore is a kind of vanadia–titania magnetite formed by erosion in the coastal zone. Because of its coarse particle size, smooth spherical particles, complex chemical composition, it has been added to sinter as an auxiliary material. Based on the principle of optimizing ore blending to strengthen advantages and weaken disadvantages, this paper used New Zealand sea sand raw ore that has not undergone any pretreatment as the main material and prepared it into oxidized pellets using a disc pelletizer and explored the influence of high-proportion unground sea sand ore on the preparation process and reduction performance of oxidized pellets. The influence of unground sea sand ore on the falling strength, compressive strength, reduction swelling index, and reduction degree of pellets was analyzed by the ICPAES, XRF, XRD, SEM-EDS, and other detection methods, and the change laws and influencing factors of oxidized pellets were analyzed. With the increase of the amount of unground sea sand ore used, the falling strength and compressive strength of the green pellets first decreased and then gradually increased, while the compressive strength of the oxidized pellets first increased and then decreased. At the same time, as the amount of sea sand ore used increased, the reduction process of pellets was restricted. The reduction swelling index and the reduction degree index generally show a downward trend. However, the compressive strength of the pellets gradually increased after reduction. Through the research on the pellet-forming performance and reduction properties of unground sea sand ore, it is shown that when the amount of unground sea sand ore used was 40%, it can still be used as raw material for blast furnace ironmaking. Thus, this research provided specific data support for iron and steel enterprises to improve the ratio of unground sea sand ore and reduce production cost.

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Woods, Dawn, Mouna Saoudi, Clinton Mayhew, and Rosaura Ham-Su. "CHARACTERIZATION OF PLUTONIUM DISTRIBUTION IN THO2–PUO2 MIXED OXIDES BY ELECTRON PROBE MICROANALYSIS." CNL Nuclear Review 7, no. 2 (December 1, 2018): 157–63. http://dx.doi.org/10.12943/cnr.2017.00014.

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Thoria–plutonia (ThO2–PuO2) pellets with a nominal composition of 9.0 wt% PuO2 were prepared using a fabrication route similar to an industrial process for production of urania–plutonia (UO2–PuO2) mixed oxide fuel. The green fuel pellets were separated into 2 batches and the sintering of each batch was carried out under a reducing atmosphere at 1820 °C or 1750 °C. The distribution of plutonium (Pu) in the sintered pellets was investigated by electron probe microanalysis using X-ray mapping and quantitative point analyses. The results show that the pellet samples consist of Pu-rich agglomerates with Pu content close to that of the mastermix blend and a thorium (Th)-rich matrix. The matrix and the Pu-rich agglomerates are separated by a transition zone with Pu content varying from practically nil to the Pu content of the Pu-rich agglomerates. X-ray maps taken from random regions of the centre of the pellets show different sizes of Pu-rich agglomerates irregularly dispersed in the Th-rich matrix. Image analysis of the Pu X-ray maps indicate that the average diameter of the Pu-rich agglomerates of the material sintered at 1820 °C and 1750 °C were 68 μm and 161 μm, respectively.

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Wei, Ru Fei, Jia Xin Li, and Guang Wu Tang. "Strength and Consolidation Mechanism of Green Pellets Containing Carbon." Advanced Materials Research 402 (November 2011): 215–20. http://dx.doi.org/10.4028/www.scientific.net/amr.402.215.

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The effects of four inorganic binders and four organic binders on strength of green pellet containing carbon were studied. The results show that phenolic resin is the best binder, compressive strength and drop strength of preheated pellet are 312.5 N and 15.1 times, respectively, when the matching was 2%. The reason is that chemical adsorption effect occurs in pellet. Strength of wet pellet is mainly maintained by capillary force. However, preheated pellet is mainly maintained by chemical adsorption effect and viscous force. Chemical adsorption effect is better than viscous force.

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Wang, Zhao Cai, Man Sheng Chu, Shi Qiang Chen, Zheng Gen Liu, Jue Tang, and Xiang Xin Xue. "Effects of B-Mg Additive on Metallurgical Properties of Oxidized Pellets." Advanced Materials Research 284-286 (July 2011): 1232–36. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.1232.

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The metallurgical properties of oxidized pellets are of great importance to achieve high efficiency and smooth running of blast furnace and gas-based direct reduction shaft furnace. In this study, the new method of adding B-Mg compound additive has been put forth to improve metallurgical properties of pellets. The effects of adding B-Mg additive on the strength of green balls, cold compressive strength, reduction swelling, and the strength after reduction and cooling of oxidized pellets are investigated through the experiments and microstructure analysis. The results revealed that, the B-Mg additive has not-so-remarkable effects on the properties of green balls. The rational addition amount of B-Mg additive is 0.6 %, and B-Mg additive make it feasible to reduce roasting temperature of the pellets. High temperature properties show remarkable improvement with the increase of B-Mg additive amount, the RSI decrease from 14.7% to 7.17%, and the strength of pellets after reduction and cooling increase from 162.5 N to 650.8 N when the addition amount increases from 0 to 0.6%.

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Patra, A. K., J. Bahadur, S. Mazumder, Sathi Nair, R. D. Purohit, and A. K. Tyagi. "Small-Angle Neutron Scattering Investigations on Sintering Behavior of Combustion Synthesized La0.8Sr0.2CrO3." Journal of Nanoscience and Nanotechnology 8, no. 4 (April 1, 2008): 2157–62. http://dx.doi.org/10.1166/jnn.2008.059.

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Pore morphology of La0.8Sr0.2CrO3 (LSC) powder compacts, sintered between 1200 °C and 1450 °C for a fixed time, has been characterized by small-angle neutron scattering (SANS) in the scattering wave vector 'q' range, 0.003–0.17 nm–1 of a double crystal based instrument. Scattering profile of green compact exhibits fractal scaling at two regions of 'q' with magnitudes of fractal dimensionality 1.8 and 2.36. Scattering profiles of sintered pellets have been modeled assuming a random distribution of near spherical pores in the solid matrix. Estimated pore size distributions of sintered pellets indicate decrease in pore volume has taken place by progressive elimination of smallest pores and growth of relatively larger pores with increasing sintering temperature. SANS results are supplemented by light scattering measurement and TEM image of powder and SEM image of the fracture surface of sintered pellet.

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Subramanyam, Vasanth. "Automatic Image Processing based Size Characterization of Green Pellets." International Journal of Automation and Smart Technology 7, no. 3 (September 1, 2017): 85–91. http://dx.doi.org/10.5875/ausmt.v7i3.1133.

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Liu, Hao, Bing Xie, and Yue-lin Qin. "Effect of Bentonite on the Pelleting Properties of Iron Concentrate." Journal of Chemistry 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/7639326.

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The physical and chemical properties such as particle size, montmorillonite content, swelling degree, water absorption, and blue absorption of A, B, and C bentonites were studied under laboratory conditions. The effects of adding different quality and different proportion of bentonite on falling strength, compression strength, and shock temperature of green pellet were investigated. The experimental results show that the montmorillonite content, water absorption, and methylene blue absorption of bentonite-B are the highest. And the quality of bentonite-B is the best, followed by bentonite-C and bentonite-A poor quality. When the amount of bentonite-B reduced from 1.5% to 1.0%, the strength of green pellets and the shock temperature both decrease. As the same proportion of A, B, and C bentonites, the green-ball strength and shock temperature are as follows: bentonite-A > bentonite-B > bentonite-C.

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35

Rajshekar, Y., J. Pal, and T. Venugopalan. "Development of hematite ore pellet utilizing mill scale and iron ore slime combination as additive." Journal of Mining and Metallurgy, Section B: Metallurgy 54, no. 2 (2018): 197–208. http://dx.doi.org/10.2298/jmmb180116008r.

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Iron ore slime is generated from mines during processing and washing of iron ore, and it is not considered for pelletizing due to its excessive fineness and high gangue content, despite its good green bonding property. Mill scale is generated from steel rolling mills and reheating furnaces; it has almost nil gangue content, but is not individually considered for pelletizing due to its poor green bonding property. If both of these two wastes are blended in combined form with hematite ore, the high gangue of slime would be balanced by the gangue free mill scale. While mill scale provides exothermic heat of oxidation of FeO and Fe3O4 in it and enhance the diffusion bonding, slime provides good green bonding property to the pellet. Therefore, in this study a good quality pellet was developed by the combined mixing of these two wastes in hematite ore without much increase in gangue content. Up to 15% of mill scale and 15% of slime could be used successfully. The developed pellets provide improved cold compressive strength (366 kg/ pellet), reducibility index (82%), and reduction degradation index (8.5%). Induration temperature could be reduced by 75 ?C, which indicates a considerable energy saving in induration furnace.

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KIM, Jae-Hyun, Kazumichi YANAGISAWA, Ayumu ONDA, Eri SASABE, and Tetsuya YAMAMOTO. "Densification behavior of hydroxyapatite green pellets prepared by different methods." Journal of the Ceramic Society of Japan 123, no. 1444 (2015): 1097–101. http://dx.doi.org/10.2109/jcersj2.123.1097.

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Xing, Zhenxing, Gongjin Cheng, Zixian Gao, He Yang, and Xiangxin Xue. "Optimization of experimental conditions on preparation of oxidized pellets with New Zealand sea sand ore." Metallurgical Research & Technology 117, no. 4 (2020): 411. http://dx.doi.org/10.1051/metal/2020043.

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In the iron and steel industry, improving the usage amount of New Zealand sea sand ore as a raw material for ironmaking can reduce the production costs of iron and steel enterprises to a certain extent. In this paper, the New Zealand sea sand ore without any grinding pretreatment was used as raw material, oxidized pellets were prepared by using a disc pelletizer, and the experimental conditions for preparing oxidized pellets were investigated and optimized. The effects of binder dosages, roasting temperature and roasting time on the properties of pellets were mainly investigated, and the effects of roasting temperature and roasting time on the microstructure of oxidized pellets was discussed by researching XRD patterns and SEM-EDS. With the increase of binder dosages, the drop strength of green pellets and the compressive strength of oxidized pellets were gradually increased. With the increase of roasting temperature and roasting time, the compressive strength of oxidized pellets increased gradually. When the amount of New Zealand sea sand ore was increased to 40–50%, the optimal process conditions for the preparation of oxidized pellets were as follows: the dosage of binder was 1.5%, the roasting temperature was 1200 °C, and the roasting time was 20 min.

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Mo, Ya Ping, Jian Jun Fan, and Yuan Wang. "Improving of Balling Performance by High Pressure Roll Grinding." Key Engineering Materials 480-481 (June 2011): 533–38. http://dx.doi.org/10.4028/www.scientific.net/kem.480-481.533.

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The experiments were conducted based on the study of one kind of ultra fine-sized magnetite concentrate with nearly 85% of the material being less than 0.044mm in size. The preliminary study has shown that this iron concentrate has middle ballabitity(K=0.61) because the iron concentrate characterized with flaky and spherical particle shapes. Such features are detrimental to the granulation of green pellets. Much more research work was carried out on how to improve balling performance by processing this magnetite concentrate with high pressure roll grinding (HPRG). The results indicated that newly-created cracks and edges would appear. Specific surface area of iron concentrate would increase from 2161.72 cm2.g-1 (base case) to 2703.51cm2.g-1 and fine particles percentage (-0.044mm) would increase to 94.69%. For the balling performance experiment, the results revealed that the ballability would increase to 1.59. Drop strength of green pellets would increase from 6.1 times/0.5m to 14.7 times/0.5m. Compression strength of green pellets would increase from 10.5N.P-1 to 12.61N.P-1. But break down temperature would decrease from more than 600°C to 480°C. The whole experiments revealed that HPRG could improve the balling performance of ultra fine-sized magnetite concentrate.

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Ling, Aw Fong, Ali Shaitir, Ari Legowo, and Agus Geter Edy Sutjipto. "The Effect of Green Body Pressure, Sintering Time and Electric Current on ZnO Crystal Growth by Electric Current Heating Method." Materials Science Forum 981 (March 2020): 3–10. http://dx.doi.org/10.4028/www.scientific.net/msf.981.3.

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There are three objectives to be achieved in this research which include to synthesis high purity ZnO pellets with different sintering time and green body pressure by using powder metallurgy process, the growth of ZnO crystal on ceramic bar by applying different current when conducting electric current heating (ECH) method and the characterization of ZnO crystal growth. In this research, high purity of ZnO powder is grinded and compressed at 3.5 tons, 4.5 tons and 5.5 tons to fabricate ZnO green pellets. Then, the ZnO green pellets are sintered for 3 hours and 5 hours. Next, the pellets are cut into bars and apply ECH method. The amount of current applied for the crystal growth are 2A and 3A. Finally, the crystal grown on the ZnO ceramic bar is characterized using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Ultraviolet-visible Spectroscopy (UV-Vis) and Photoluminescence Spectroscopy (PL). High purity ceramic pellets are successfully synthesis by powder metallurgy process. By conducting ECH method, crystal are grown on the surface of ceramic bar. Most crystal structure found in ZnO ceramic bar is needle-liked rod structure which is hexagonally formed by many nanorod. The crystal grown in (100) orientation with the crystalline size of from 57.80 nm to 100.31 nm. The band gap energy obtained from UV-Vis were found between 3.2 eV to 3.4 eV which is nearly similar to the theoretical value of 3.37 eV. Lastly, PL emission measurement give the peak that range between 579 nm to 587 nm which indicate that the sample exhibit yellow colour. Among three different pressure applied, 4.5 tons gives the lowest emission energy. It is considered as the critical pressure in the synthesis of ZnO crystal. The intensity of PL is considered inversely proportional to intensity of XRD in [100] direction. Pressing pressure doesn’t show significant effect on the crystal growth of ZnO but current applied during ECH method and sintering time do give effect on UV-Vis absorption spectra and XRD result respectively.

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Forsmo, S. P. E., S. E. Forsmo, P. O. Samskog, and B. M. T. Björkman. "Mechanisms in oxidation and sintering of magnetite iron ore green pellets." Powder Technology 183, no. 2 (April 2008): 247–59. http://dx.doi.org/10.1016/j.powtec.2007.07.032.

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Bhuiyan, I. U., J. Mouzon, S. P. E. Forsmo, and J. Hedlund. "Quantitative image analysis of bubble cavities in iron ore green pellets." Powder Technology 214, no. 3 (December 2011): 306–12. http://dx.doi.org/10.1016/j.powtec.2011.08.028.

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Cuevas-Arizaca, Edy E., Máximo Rondón R, René R. Rocca, M. B. Gomes, B. Cortez, Carlos D. Gonzales-Lorenzo, J. H. Takara, et al. "Study of thermoluminescence of green quartz pellets for low dose dosimetry." Radiation Physics and Chemistry 177 (December 2020): 109142. http://dx.doi.org/10.1016/j.radphyschem.2020.109142.

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De Moraes, Sandra Lúcia, José Renato Baptista De Lima, João Batista Ferreira Neto, Cátia Fredericci, and Eduardo Maziero Saccoccio. "Binding Mechanism in Green Iron Ore Pellets with an Organic Binder." Mineral Processing and Extractive Metallurgy Review 41, no. 4 (June 4, 2019): 247–54. http://dx.doi.org/10.1080/08827508.2019.1604521.

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Fournier, P., R. Gagnon, and M. Aubin. "Formation of superconducting pellets and oriented films from Y2BaCuO5(green phase)." Journal of Applied Physics 67, no. 8 (April 15, 1990): 3776–79. http://dx.doi.org/10.1063/1.345022.

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45

López-Moreno, Francisco Javier, Santiago Atero-Calvo, Eloy Navarro-León, Begoña Blasco, Teresa Soriano, and Juan Manuel Ruiz. "Evaluation of Physiological and Quality Parameters of Green Asparagus Spears Subjected to Three Treatments against the Decline Syndrome." Agronomy 11, no. 5 (May 10, 2021): 937. http://dx.doi.org/10.3390/agronomy11050937.

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Green asparagus (Asparagus officinalis L.) is a widely grown and consumed crop which provides high-level nutritional interest. In recent years, the decline syndrome in asparagus plantations has been rapidly augmenting. This syndrome causes the early death of whole plants, also negatively affecting the new replanting. Decline causes notable economic losses in the sector. The objective of this work was to verify the effect of different treatments against asparagus decline syndrome on the physiological parameters and nutritional quality of the spears. To meet the objective, four different treatments were applied to asparagus plots strongly affected by decline syndrome: (T1) untreated control soil, (T2) biofumigation with Brassica pellets, (T3) biofumigation with chicken manure pellets, and (T4) disinfestation of the soil with Dazomet. The cumulative yield and physiological and quality parameters of green asparagus spears were studied. Thus, malondialdehyde (MDA), photosynthetic pigments, glutathione (GSH), ascorbate (AsA), total phenols, flavonoids, anthocyanin, antioxidant test, mineral nutrients, and the amino acid profile were measured on asparagus spears. The results showed that the Brassica pellets and Dazomet treatments were the most effective against the damage caused by the decline syndrome. However, it would be necessary to monitor the evolution in the following years.

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Rudling, D. "Post-Medieval Pottery (16th/17th-18th century)." Proceedings of the Prehistoric Society 51, S2 (1985): 26. http://dx.doi.org/10.1017/s0079497x00078221.

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Five sherds were submitted for study: three from trench A, context 1; and two from trench E, context 1. Those from trench A include: 1 sherd of orange ware with internal mottled green glaze; 1 sherd of orange ware with intelai orange-brown glaze; and 1 sherd of Staffordshire combed ware. Of the Merds from trench E, 1 is of pale orange/buff ware with internal mottled green glaze; and the other is of orange ware with partial external light green glaze and internal green glaze above applied, raised decoration in the form of pellets and lines.

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Engesser, J. "Nitrogen oxide (NOx) emission reduction during pellet induration by fuel addition to the green pellets and decreased excess air." Mining, Metallurgy & Exploration 21, no. 1 (February 2003): 9–16. http://dx.doi.org/10.1007/bf03403296.

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Lessing, Paul A., W. Roger Cannon, Gerald W. Egeland, Larry D. Zuck, James K. Jewell, Douglas W. Akers, and Gary S. Groenewold. "Strength loss in MA-MOX green pellets from radiation damage to binders." Journal of Nuclear Materials 437, no. 1-3 (June 2013): 229–34. http://dx.doi.org/10.1016/j.jnucmat.2013.02.019.

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Dwarapudi, S., S. M. Rao, J. V. S. N. Murthy, D. D. Parida, and K. S. Raju. "Effect of activated bentonite on properties of green and fired chromite pellets." Ironmaking & Steelmaking 35, no. 4 (May 15, 2008): 308–14. http://dx.doi.org/10.1179/174328108x295721.

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Forsmo, S. P. E., A. J. Apelqvist, B. M. T. Björkman, and P. O. Samskog. "Binding mechanisms in wet iron ore green pellets with a bentonite binder." Powder Technology 169, no. 3 (November 2006): 147–58. http://dx.doi.org/10.1016/j.powtec.2006.08.008.

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Journal articles on the topic 'Green pellets'

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