CLICK HERE ---> https://bytlly.com/2tDYnD
The dynamics of fires in the territory of Eastern Siberia (the territory of the Lena River basin in the middle reaches) has been studied with the use of materials from retrospective satellite imagery. The dependence of the burnability of forests in the local territories of Eastern Siberia on the level of heat and moisture supply is shown. The range of the burnability index (the number and area of fires) for the study area under extreme drought conditions was revealed, confirmed by retrospective data. It is shown that potentially the average annual values of the number of fires can be 2.5 times higher than the current statistics. Based on the invariant NDVI and NDWI indices, a range of changes in the characteristics of post-fire areas has been identified, which indirectly determines the level of fire impact on vegetation and the humidification regime.
Coating plays a very important role on the refractory life in burning zone, of the rotary kiln, where the condition is most arduous. The mechanism of coating formation and the stability of coating largely determine the refractory life. The factors those help formation of a good coating and influence the stability of coating formed, are discussed in detail. The role of liquid phase on coating formation is discussed. The test to simulate the coating formation on refractory, in laboratory, is discussed in detail. A schematic diagram shows the relation between Alumina ratio, Silica modulus and the kiln coating behavior. A chart is given to show the relation between the free lime in clinker and burnability behavior of the coating.
One the most important contributions of this formula is its recognition of the importance of the clay raw material mineralogy in determining the energy consumed in clinker formation. However, a weaknesses is not making any distinction between the types of silica present in the kiln feed. The SiO2 present as quartz in the kiln feed is recognised to have a significant effect on the burnability of the kiln feed.
This overall energy for clinker formation lies in the middle of the range of 16301840 kJ/kg clinker which has been observed in practice. This FLS approach is good because it allows the heat of clinker formation to be calculated from the raw mix composition without needing to identify the exact non-carbonate minerals present. However, it does not explain the observed impact of the SiO2 mineral form on the burnability.
In fact as SiO2 in quartz is not associated with any CaO, MgO, K2O or Na2O the methodology calculates a lower heat of clinker formation if the SiO2 is present as quartz. The impact of quartz on the burnability of raw mix is reduced by finer grinding and changing the granulometry of the raw mix. Thermodynamic considerations alone are insufficient for explaining burnability or heat of clinker formation. Reaction kinetics also have to be taken into consideration, we will discuss these in the next session of the course.
The paper presents experimental results regarding the synthesis of Portland clinker starting from raw mixes based on two types of clayey precursors, i.e., clay and marl (the most common types of raw materials used in the cement industry), with and without glass waste content. The soda-lime glass waste addition (5.36-5.59 wt %), used to control the silica ratio of the raw mix, improved the raw mix burnability and decreased the calcination temperature (by 20 C), leading to a decrease in fuel consumption and contributing to the reduction in CO2 emissions associated with clinker and cement production. The clinkers obtained by the calcination of raw mixes with glass waste content at 1430 C with a 30 min plateau had a similar mineralogical composition and microstructure to the clinkers obtained from the reference raw mixes and fulfilled the requirements of the specific standard EN 197-1. The obtained clinkers were used to produce two types of Portland cement, i.e., a unitary cement (CEM I) and a binary blended cement with slag (CEM II/B-S). The main characteristics of these cements, i.e., loss on ignition, insoluble residue, sulfate and chloride contents, as well as the setting time and soundness, meet the conditions stipulated in the EN 197-1 standard. The values of compressive strength, assessed on mortars after 2, 7 and 28 days of curing, allow the classification of all CEM I cements in the 42.5 R class. In the case of CEM II/B-S cements, those obtained from raw mixes with clay can be classified in the 42.5 N class, while those obtained from raw mixes with marl are classified in the 32.5 R class.
This work reported a process for the preparation of Portland cement clinker from sulfuric acid leaching residue of coal fly ash. Aluminum and iron in fly ash were effectively leached by sulfuric acid leaching, and the silica was all concentrated in the acid leaching residue. The chemical analysis showed that the content of SiO2 in the leaching residue was 79.1% and the leaching residue contained a small amount of Al2O3, CaO and Fe2O3, which could replace clay as the raw material for the preparation of Portland cement clinker. The effects of main process conditions on the quality of prepared cement clinker were studied. The results showed that the burnability of the raw material with clinker rate value KH = 0.92, SM = 2.1, IM = 1.2 and leaching residue content of 26.98% was excellent and good. The mineralogical analysis and microscopic examination showed that the good quality clinker was obtained under the conditions of sintering temperature of 1450 C and holding time of 60 min, and the tricalcium silicate phase was well developed. Based on this study, acid leaching residue of coal fly ash was viable as an effective, alternative raw material in Portland cement production.
Oil shale (in German Olschiefer) is a sedimentary rock rich inorganic matter that can be industrially processed into oil. It is just one ofthe names of the rock. The alternative names in different languages refer tothe burnability (combustibility) of the shale (in Estonian polevkivi, inRussian gorjutchii slanets, in German Brennschiefer). Considering that thename of this rock is determined by the way of utilizing it for oilprocessing, it is more rational to call it oil shale. 781b155fdc