Thermochemical equilibrium calculations indicate the possibility of considerable fuel savings and CO 2 emission avoidance in the three steps of the Pidgeon process: (a) calcination of dolomite; (b) production of ferrosilicon from quartz sand, coal, and iron oxide; (c) silicothermic reduction of calcined dolomite by ferrosilicon to …
The calcination of dolomite has been studied as a function of temperature, particle size, and P co 2. An investigation concerning possible mass transfer restrictions for the experimental system and a model investigation of the calcination rate in CO 2 atmosphere has been made. Further, the effect of calcination on the BET surface and the BET ...
The thermodynamic analysis of the thermal decomposition reaction of carbonates showed that the temperatures of thermal stability of dolomite and magnesium carbonate are very similar. Kinetics of isothermal and non-isothermal decompositions of natural dolomite in air atmosphere were investigated. Under the examined conditions, …
However, the energy required for clay calcination is significantly lower than that required for lime and magnesia production (see Sect. 3), so some modifications may be required. Unlike in the manufacturing of lime and magnesia, the clay rock may not need significant crushing prior to calcination. 2.8.3 Expanded clay manufacturing plants
Kinetics and cyclability of limestone (CaCO3) in presence of steam during calcination in the CaL scheme for thermochemical energy storage. Chemical …
Calcination promotes the cracking of the dolomite surface as the release of carbon dioxide proliferates the mesopores through the calcined dolomite [43]. Thus, the calcined dolomite has a larger specific surface area, pore volume, and average pore size than the RawDo. The dolomite yield Y at different calcination temperatures is shown in …
First, the raw dolomite is crushed and screened to remove any impurities. It then goes through a calcination process, which heats the dolomite to high temperatures …
CaO and MgO are important industrial raw materials commonly produced by either the decomposition of calcium carbonate at about 900 °C, or the calcination of dolomite, a mixed calcium and magnesium carbonate, calcined either to MgO.CaCO3 at about 750 °C, or to MgO.CaO at 900 °C. ln this research, the …
An experimental campaign was carried out in order to evaluate the effect of thermal pretreatment on the CO 2 carrying capacity of dolomite. Table 1 summarizes the 11 experiments corresponding to the study of the main influential factors in the calcination phase:. Atmosphere composition during thermal stabilization: N 2 (mild) 50/50% N …
DOI: 10.1016/j.jclepro.2023.140173 Corpus ID: 266324532; A rapid and environment-friendly process for dolomite pellets calcination with Joule-heating @article{Luo2023ARA, title={A rapid and environment-friendly process for dolomite pellets calcination with Joule-heating}, author={Xiao Luo and Peng Zhao and Jiaqi Guo and Jiangjiang Li}, …
The required calcination temperatures for dolomite can be comfortably reached using inexpensive solar salt (0.6 NaNO 3 + 0.4 KNO 3) that is already in use in a number of concentrated solar power ...
The conversion of dolomite calcination reaches 98 to 99% as the calcination conducted at 800 and 900 C. The experimental results were presented using various kinetics models.
2 Fine crushing: Then the dolomite rock enters a cone crusher for fine crushing. It is crushed into dolomite blocks of small particle size to achieve sufficient dissociation of the useful material of the ore. ... The key equipment of the calcination process is the rotary kiln. Ftmmachinery Rotary Kiln has the following unique …
For the purpose of using dolomite as a magnesia binder, the authors have considered phase transformations as a result of dolomite calcination in both pure form and when …
A lower calcination temperature of dolomite (1200 C) determines a high increase in the system temperature when calcined dolomite is mixed with KH2PO4 (MKP) solution and also a rapid expansion of the paste. The increase in calcination temperature up to 1400 C reduces the oxides reactivity; however, for lower
As the increase of the productivity of the magnesium,the technology of the magnesium has been improved.During the recent years,the cost of material and the cost of energy per output has been reduced.The progress of technology are always associated with the appearance of new equipment.This article introduces two important kilns during the …
determine the conversion of dolomite calcination. The conversion of dolomite calcination is calculated by the amount of carbon dioxide that is released from the feed, which is assumed from the weight of initial feed subtracted by the weight of final sample. 2.1.5 Actual Temperature Distribution in Rotary kiln
Compositional analysis demonstrated that only half-decomposition occurred when salt-bearing dolomite was calcined at a temperature of 723–923 K, leading to the formation of CaO-free HCDs composed of periclase and Mg-calcite having a Mg level of 2.0–10.5 mol%. ... medicine, and construction. However, advanced calcination …
Dolomite, a calcium magnesium mineral (CaMg(CO3)2), is considered an undesirable accompanying mineral in the phosphoric acid production process and, as such, large quantities of this mineral are available in Florida. This study is aimed toward the characterization of the high-concentration phosphatic dolomite pebbles (handpicked …
The calcination of dolomite has been studied as a function of temperature, particle size, and P-CO2. An investigation concerning possible mass transfer restrictions for the experimental system and a model investigation of the calcination rate in CO2 atmosphere has been made. Further, the effect of calcination on the BET surface and the BET ...
The reaction during calcination includes the decomposition of dolomite and calcite (i.e. the liberation of CaO and MgO), lattice failure of minerals and fusion reaction between oxides. We focus on the primary changes of the mineral phases identified via XRD during the calcination of mixed SAD–dolomite; the results are shown in Fig. 4. …
Thermogravimetric analysis (TGA) was used to determine the activation energy for the calcination and re-carbonation reactions of the dolomite pebbles in …
Natural dolomite was calcined at 700–900 °C under air and an Ar gas flow atmosphere to characterize its sorbency potential for borate.A sequential decarbonation occurred with increase in calcination temperature, that is, transformation of CaMg(CO 3) 2 to MgO and CaCO 3 up to 700 °C and CaCO 3 to CaO from 700 to 900 °C. The surface …
The present work reports an in situ XRD analysis on the calcination of natural dolomite under a pure CO 2 atmosphere. The main goal is to provide an insight on how calcination kinetics and the crystal structure of the calcination byproducts are affected by the addition of H 2 O to the calciner at a very low concentration. The working …
DOI: 10.1016/J.HYDROMET.2019.06.018 Corpus ID: 198367187; Investigation of decomposition of dolomite and distribution of iodine migration during the calcination-digestion process of phosphate ore
Calcination of dolomite and limestone particles was studied, without and with adding steam. Steam accelerates the reaction rate and reduces the calcination …
The use of wastes of marble powder (WMP) and dolomite as sorbents for CO 2 capture is extremely promising to make the Ca-looping (CaL) process a more sustainable and eco-friendly technology. For the downstream utilization of CO 2, it is more realistic to produce a concentrated CO 2 stream in the calcination step of the CaL process, so more severe …
A schematic sketch of the method used to prepare dolomite-derived composite pellets is presented in Fig. 1.The naturally occurring dolomite powders were precalcined at 900 °C for 60 min. Weighed amounts of calcined dolomite were dissolved in a 50 vol % propionic acid solution at 50 °C, and the solid-to-liquid ratio was set to 1:15.
Knowledge of the reaction mechanisms of dolomite calcination under conditions present in pressurized fluidized-bed gasification processes is useful for …
It can be seen from Fig. 15 that when the calcination time was 5 min, dolomite was almost entirely decomposed into CaO and MgO. As the calcination time was prolonged, the diffraction peaks of the materials remained unchanged, but the peak intensity was enhanced. It was found that prolonging the roasting time was beneficial to …
