ПроМислове ЗАстосувАння доМенного ШлАку в якості ЗАМінникА Піску нА цеМентноМу ЗАводі ХАджАр-сууд (Алжир) purpose. This study is conducted on the use of industrial waste (blast furnace slag) from the El-Hadjar steel plant located in eastern Algeria. The research aims to understand the behaviour of the addition of Slag as raw material (replacing sand) in the preparation of the mixture before baking in the rotary kiln at the Hadjar-Soud cement plant in Skikda. Methodology. The representative samples taken from the cement plant site are subjected to grinding of the mixture of limestone, slag, clay and iron ore, the material prepared at a grain size of less than 50 μ is subjected to a physicochemical characterization. The prepared sample is placed in a furnace with a temperature of up to 1450 °C. findings. The results obtained during the tests show that the addition of slag into the raw meal does not affect the chemical or mineralogical composition of the clinker. However, the clinker obtained reveals significant results and meets the Algerian standard NA 442 2000 (CPJ CEM II/A 42.5). The addition of slag to replace the sand has allowed us to reduce the annual CO 2 emission rate by about 17.5 %, and contributes to the reduction of pollution. originality. The originality of this work is the preparation of the raw cement meal, based on slag (already decarbonated material) instead of sand. As a rule, for the production of cement clinker, the proportion of the raw materials is: limestone (77-80 %), clay (16-18 %), iron ore (1.5-3 %) and sand (2-4 %). In the present work, the proportions for the production test of the slag-based clinker are respectively: limestone 70 %, slag 9 %, clay 19.2 % and iron ore 1.8 %. The estimate of the annual CO 2 emission rate in the cement plant was carried out by the Software (GEMIS 4.7). practical value. The process for obtaining slag-based clinker (steel waste) is probably of great importance for the production of cement for several reasons: the production of one tonne of Clinker at a minimum cost, along with management of non-renewable natural raw materials, such as sand and limestone deposits, and work towards sustainable development.

Mining processes in the iron ore mine of Boukhadra, Tebessa (NE Algeria) generated thousands of tons of mining wastes every year, which represents a real threat to the environment, leading to hazardous effects for the resident population of the region. The aim of this study is the selective sorting of the Boukhadra mining wastes for valorization. This will facilitate the recycling of the mineral substances (limestone, iron, marls) on the one hand and it makes it possible to minimize the volume of stocks and their environmental impacts on the other hand. To do this, and taking into account the chemical properties of wastes, we recommend an optical separation management using a color camera and a microprocessor linked to the ejection system (valve or pump), the color measurement tests performed on Boukhadra waste rocks samples using Matlab codes converted from Algorithms showed that each rock has a specific color (Red Green Blue value) or RGB. For this purpose, the use of three optical separators that sort according to algorithmic commands (RGB interval) will contribute to the separation of the Boukhadra mining wastes and consequently simplify their reuse.

The present article is devoted to the development of a hematite-poor ore mine in Ouenza, which does not meet the steelmaker's requirements. Significant volumes are stored at the pithead of the mine, and the reserves are estimated at over 100 million tones. This enormous quantity of mining waste occupies an important space and poses a real threat to the environment as well as for the mining city of Ouenza. In order to solve these socio-economic and environmental problems, a sustainable development and a better quality of life for inhabitants of this region is needed. For this, representative samples were taken at the level of the dumps. Taking into account the natural characteristics of the stock namely; mineralogical composition, iron content, particle size of the rock mass, as well as the release mesh of iron minerals from the gangue. Firstly, tests are conducted on the recovery by radiometric separation of iron-rich pieces and graded. Then the rest of the ore was subjected to mechanical preparation followed by enrichment, which will be the subject of another study. The research is conducted on samples to determine the optimal parameters of the γ-rays absorption tested by radiometry; these parameters were the velocity of the conveyor belt and the time of exposure to γ-rays. The obtained results by this valorization process are very significant: iron content 53.5% and 8.3% recovery.

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This work examines a tuff from the Tinebdar deposit located in Sidi Aich (east Algeria) for possible use as an alternative material for the adsorption of Asucryl red (a textile dye). Natural tuff represents an economic and environmentally friendly alternative compared to synthetic zeolites. The starting materials were characterized by means of powder X-ray diffraction, Brunauer–Emmett–Teller-specific surface area and pore diameter analysis. Batch experiments were performed and various parameters that have an effect on the adsorption process (i.e. pH, clay amount, contact time and initial concentration) were investigated. The <125 μm grain-size fraction of the tuff contains 45 wt.% mordenite. The adsorption equilibrium was established in 10 min and the adsorption kinetics were better described by the second-order kinetic model. The adsorption isotherm of the results obtained fits better to the Langmuir and Timkin models. The adsorption capacity qt varies from 60 to 70 mg g–1 with temperature increasing from 293 to 333 K. The thermodynamic nature of the adsorption process was determined by calculating ΔH°, ΔS° and ΔG° values. The positive value for ΔH° confirms that the adsorption is endothermic.

The objective of this article is to study the possibilities of enrichment of the iron ore from Jebel Anini and to develop these mineral resources in order to use them in the metallurgical complex of Annaba. Representative samples were taken from Anini iron mine located in the northwest of the Wilaya of Setif. After sampling, mineralogical, chemical and size particles’ characterization was carried out. However, the analyzes performed by (XRD, SEM and FX) show that the ore is iron type hematite clay and siliceous gangue. The average contents of Fe2O3, SiO2 and Al2O3 are respectively 55%, 26.20% and 12%. The data collected after several preliminary tests of enrichment by washing (wet sieving) of the ore reveal significant results in iron content is 62% Fe2O3, 2 to 3% of quartz and 2 to 3% of clay. The tests conducted by wet magnetic separation show, on the one hand, remarkable results in iron content of 65.11% against 2.46% SiO2 and1.73% Al2O3 and , on the other hand, that the enriched product meets the standards required by metallurgy, releases from processes can be used as an addition in the preparation of cement.

Purpose. The main purpose of our research work involves the characterization and environmental management of waste rocks from Djebel Onk phosphate deposit. We propose a valorization of this product as an addition to cement manufacturing technique (the development of a new composite cement based on waste rocks of Djebel Onk phosphate deposit).Methodology. A comparative study was conducted on the physical and mechanical parameters of the composite cement based on phosphate waste rocks with cement without additions (CWA) and other cements based on pozzolan and the blastfurnace slag additives. These additives make, respectively, at mass contents of 5, 10, 15, 20, 25 and 30 % for each addition.findings. The studies and tests conducted have enabled us to deduce that it is clear that the use of phosphate waste rocks as an additive in the manufacture of cement gives better compressive strengths compared to other additives. Thus, this study has shown that it is possible to incorporate a considerable amount of phosphate waste rock from Djebel Onk deposit in the cement.originality. It becomes possible to reduce the amount of phosphate waste rocks of Djebel Onk for costeffectiveness and eliminate their impact from the environmental point of view.Practical value. The reuse of waste as an alternative raw material in building materials is a promising environmental solution. This way of valorization reduces large quantities of tailings and thus their environmental impact, as well as contributes to the pres ervation of nonrenewable natural resources intensively used in construction (clays, limestone, sand, and others).