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This is an article in the field of metallurgical engineering. The vanadium ore with vanadium containing sericite and illite in Shaanxi province was taken as the research object, low-temperature sulfuric acid ripening-water leaching process was used to extract vanadium. The effects of ripening temperature, ripening time, sulfuric acid dosage, sodium chloride dosage, leaching temperature, leaching time and liquid-solid ratio on vanadium leaching rate were investigated. The results show when 25% sulfuric acid and 0.8% sodium chloride are added to the stone coal vanadium ore, the sample is aged at 130 ℃ for 8 h, and the sample is leached at 55 ℃ for 2 h under the conditions of liquid-solid ratio of 1.5∶1, the vanadium leaching rate can reach more than 89%. This indicates that it is feasible to adopt low temperature sulfuric acid ripening and water leaching process to extract stone coal type vanadium ore.

This is an essay in the field of metallurgical engineering. Taking a lithium mica ore in Jiangxi as raw material, the roasting-leaching, mixed acid ripening, direct acid leaching and alkali pressure cooking process were explored. Finally, the sulfate roasting-water leaching method was used to extract lithium from lithium mica ore. At the same time, the effects of roasting temperature, roasting time, additive type, additive amount, liquid-solid ratio and leaching temperature on lithium leaching rate were studied. The results show that roasting temperature has a great influence on lithium leaching rate, and the leaching effect of lithium is better in the appropriate roasting temperature range. 40% potassium sulfate, 20% sodium sulfate and 20% calcium oxide were added to the lithium mica ore, calcinated at 900 ℃ for 1 h, and the calcine was leached at room temperature for 1 h according to the liquid-solid ratio of 1∶1. The lithium leaching rate reached 94.87%. This shows that the effect of using sulfate as an additive to roast and extract lithium is better. Through the study of the roasting mechanism, it can be seen that the mineral structure is reconstructed after the addition of sulfate after high temperature roasting. The sodium and potassium ions in the ore are replaced with lithium ions in the lithium mica, so that they are separated from the insoluble aluminum silicate minerals to generate soluble lithium sulfate, which is then immersed in water and then into the solution.

Beam hopping (BH) technology is one of effective ways to solve limitation of beam resources and enhance the system coverage ability of low earth orbit (LEO) satellite systems.Existing research typically considers beam hopping resource allocation for a single LEO satellite, however, the actual LEO system is covered by multiple satellites in multiple orbits, and existing research ignores beam interference between satellites, which can easily lead to a decrease in system throughput and service quality.To address these issues, this paper designs an interference aware cooperative resource allocation for LEO with beam hopping (IARA-BH), aiming to maximize the beam service satisfaction (BSS).A BH resource allocation scheme by multi satellite interference coordination based on simulated annealing algorithm (MSIC-SAA) is proposed to solve the optimization problem.Simulation experiments show that compared to beam hopping resource allocation schemes that only consider a single satellite, the BSS of the MSIC-SAA algorithm has been improved by 47.24%, the average signal to interference noise ratio (SINR) has been improved by 27.40%, and the system throughput has been improved by 22.92%.

According to the characteristics of cyanine tailings in Xiajiadian gold ore, hydrogen peroxide oxidation method and sodium percarbonate (solid hydrogen peroxide solution) oxidation method were carried out to test and study the effect of cyanogen-breaking tailings, aiming to make the cyanogen-breaking tailings meet the backfilling and utilization requirements of HJ 943-2018 《Technical Specification for The Control of Cyanide Residue pollution in the Gold Industry》. The results showed that the cyanide breaking effect of sodium percarbonate (solid hydrogen peroxide) oxidation method was not as good as that of hydrogen peroxide, but the pH value of cyanogen-containing tailings slurry was adjusted to 9, and 2 g/L hydrogen peroxide was used to break the cyanide for 1 h without adding the catalyst CuSO4. The total cyanide content of tailings could be reduced to less than 0.9 mg/kg, and the leaching toxicity index of tailings could meet the requirements of standard backfill utilization.

Mineral processing technology and technological mineralogy were studied complex polymetallic lead-copper-zinc sulfide ores from Inner Mongolia. Findings show that the valuable elements in the ore are Cu, Pb, Zn and Ag, and the copper, lead and zinc minerals are metasomatized and wrapped each other, among which galena and chalcopyrite are wrapped, and the particle size of the wrapped galena is not uniform. Galena and sphalerite are mostly in continuous relationship, and the contact surface between them is smooth and straight, which is easy to separate. The silver mineral is associated with these metal minerals, so the ores was used by the technological process of mixed flotation of copper and lead, separation of copper and lead and zinc flotation from tailings. Finally, a total of 3 concentrate products were obtained. In the copper concentrate, the average grades of Cu and Ag were 18.41% and 594.82 g/t with 86.53% and 25.30% recovery rates. In the lead concentrate, the average grades of Pb and Ag were 62.70% and 428.05 g/t with 85.01% and 54.62% recovery rates. In the zinc concentrate, the average grades of Zn and Ag were 28.12% and 165.75 g/t with 59.99% and 4.80% recovery rates; The total recovery of silver reached 84.72%, which realized the comprehensive recovery of valuable elements in ore.

In order to improve the utilization efficiency of acid leaching vanadium tailing, the sintered ceramsite for building was prepared by adding clay and fly ash with Shangluo Qianjiaping vanadium tailing as the main raw material. The proportion of materials, the parameters of granulation process, the preheating and roasting conditions in the preparation of ceramsite were systematically studied. The results show that when the ratio of vanadium tailing, clay and fly ash is 6:1:3, granulating water granulation water consumption is 18%, granulation time is 15 min, preheating temperature is 400℃, preheating time is 30 min, roasting temperature is 1160℃, roasting time is 20 min, the high strength ceramsite with compression strength of 11.58 Mpa, packing density of 1014.7 kg/m3 and water absorption of 5.61% can be obtained. SEM and XRD analysis indicate that in the process of ceramsite synthesis, quartz, anorthite and albite phases has been generated and formed mineral aggregates with compact structure and good pore skeleton, thus increasing the strength of ceramsite.