Solar Activity Modeling: From Subgranular Dynamical Scales to the Solar Cycles

Dynamical effects of solar magnetoconvection span a wide range spatial and temporal scales that extends from the interior to the corona and from fast turbulent motions to the global-Sun magnetic activity. To study the solar activity on short temporal scales (from minutes to hours), we use 3D radiative MHD simulations that allow us to investigate complex turbulent interactions that drive various phenomena, such as plasma eruptions, spontaneous formation of magnetic structures, funnel-like structures and magnetic loops in the corona, and others. In particular, we focus on multi-scale processes of energy exchange across the different layers, which contribute to the corona heating and eruptive dynamics, as well as interlinks between different layers of the solar interior and atmosphere. For modeling the global-scale activity we use the data assimilation approach that has demonstrated great potential for building reliable long-term forecasts of solar activity. In particular, it has been shown that the Ensemble Kalman Filter (EnKF) method applied to the Parker-Kleeorin-Ruzmakin dynamo model is capable of predicting solar activity up to one sunspot cycle ahead in time, as well as estimating the properties of the next cycle a few years before it begins. In this presentation, using the available magnetogram data, we discuss development of the methodology and forecast quality criteria (including forecast uncertainties and sources of errors). We demonstrate the influence of observational limitation on the prediction accuracy. We present the EnKF predictions of the upcoming Solar Cycle 25 based on both the sunspot number series and observed magnetic fields, and discuss the uncertainties and potential of the data assimilation approach for modeling and forecasting the solar activity

Solar Activity Modeling: From Subgranular Dynamical Scales to the Solar Cycles

The dynamical effects of solar magnetoconvection span a wide range spatial and temporal scales that extend from the interior to the corona and from fast turbulent motions to global magnetic activity. To study the solar activity on short temporal scales (from minutes to hours), we use 3D radiative MHD simulations that allow us to investigate complex turbulent interactions that drive various phenomena, such as plasma eruptions, spontaneous formation of magnetic structures, funnel-like structures and magnetic loops in the corona, and others. In particular, we focus on multi-scale processes of energy exchange across layers of the solar interior and atmosphere, which contribute to coronal heating and eruptive dynamics. For modeling global-scale activity, we use a data assimilation approach that has demonstrated great potential for building reliable long-term forecasts of solar activity. In particular, it has been shown that the Ensemble Kalman Filter (EnKF) method applied to the Parker-Kleeorin-Ruzmakin dynamo model is capable of predicting solar activity up to one sunspot cycle ahead in time, as well as estimating the properties of the next cycle a few years before it begins. In this presentation, using the available magnetogram data, we discuss development of the methodology and forecast quality criteria (including forecast uncertainties and sources of errors). We demonstrate the influence of observational limitations on prediction accuracy, and we present the EnKF predictions of the upcoming Solar Cycle (25) based on both the sunspot number series and observed magnetic fields and discuss the uncertainties and potential of the data assimilation approach for modeling and forecasting solar activity

Modelling of methane partial oxidation in an asymmetric multilayered membrane reactor

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Melting of calcined pellets with production of high-carbon ferrochrome

The use of composite calcined pellets obtained according to a sequential scheme of chemical and gravitational beneficiation of dump sludge tailings of the Dubersay tailing dump as a part of a charge with factory chromium concentrate enabled to obtain high-carbon ferrochrome FeCr70C90Si4LP China Standard where the low phosphorus content is not more than 0,03 % and that of sulfur is not more than 0,1 %. The obtained samples of high-carbon ferrochrome and slag were studied. The maximum chromium content was 57,14 % at 1 750 °C, the charge sample included 50 % of experimental pellets and 50 % of factory concentrate and reducing agent 17 %, chromium recovery into the alloy was 80 %

Beneficiation of chrome slurry tailings at Donskoy mining and beneficiation plant (DMBP) JSC to produce hard pellets

The article is about the problem of beneficiation of finely dispersed chromium slurry tailings of “Donskoy Mining and Beneficiation Plant” JSC by chemical and gravitation methods. Chemical destruction of chromium spinelids by sulphation with a mixture of ammonium sulphate and sulphuric acid enables to transfer a part of magnesium oxide to a water-soluble state and further gravitation beneficiation on concentration tables to obtain a fine-grained rich chromium concentrate. Silica, calcium, and iron oxide additives are used to produce pellets from the fine chrome concentrate, serving as binding agents and enabling the production of hard chrome pellets during roasting. In the future, roasted pellets will be used in the smelting of high-carbon ferrochrome in electric furnaces

The process of beneficiation of fine chrome sludges on concentration tables

Processing industrial products and technogenic waste is an urgent task in mining and metallurgical industry. In Kazakhstan, processing of chrome ores of the Kempirsay group of deposits creates more than 15 million tons of sludge tailings with a chromium oxide content of up to 30 wt. %. The best results of processing fine chrome raw materials are demonstrated by Turkish enterprises that use sludge separation by size classes and enrichment on concentration tables. The authors performed a research on Dubersay tailing dump chromium sludge enrichment (Kazakhstan) using similar technological approaches, which allowed to obtain concentrates containing 51 wt.% Chromium oxide and increase the yield of rich fine chromium concentrates by 14 % compared to the existing enrichment scheme

Beneficiation of chrome slurry tailings at Donskoy mining and beneficiation plant (DMBP) JSC to produce hard pellets

The article is about the problem of beneficiation of finely dispersed chromium slurry tailings of “Donskoy Mining and Beneficiation Plant” JSC by chemical and gravitation methods. Chemical destruction of chromium spinelids by sulphation with a mixture of ammonium sulphate and sulphuric acid enables to transfer a part of magnesium oxide to a water-soluble state and further gravitation beneficiation on concentration tables to obtain a fine-grained rich chromium concentrate. Silica, calcium, and iron oxide additives are used to produce pellets from the fine chrome concentrate, serving as binding agents and enabling the production of hard chrome pellets during roasting. In the future, roasted pellets will be used in the smelting of high-carbon ferrochrome in electric furnaces