NOUFERROUS METALLURGICAL EQUIPMENT

Abstract:Steel slag is the main by-product in the steelmaking process, and the development of its treatment and utilization technology has received widespread attention. Given the importance of green and sustainable development in the steel industry, it is particularly important to find an efficient and clean comprehensive utilization technology for steel slag. Based on above, this paper reviews the principles, research progress, and application status of existing processes from three aspects: primary treatment, secondary treatment, and resource utilization of steel slag. It also looks forward to the difficulties, challenges, and prospects faced by current research in industrial production. In primary treatment, the fourth-generation high-efficiency pressurized tank-based thermal quenching technology and equipment for molten steel slag have been widely adopted by major steel companies both domestically and internationally, achieving a domestic market share of over 90% and a slag treatment rate of up to 99%. In secondary treatment, electromagnetic separation technology is employed, which doubles the recovery rate of slag iron content, compared to systems without a magnetic field. The paper aims to provide a reference for further in-depth research on steel slag treatment and resource utilization.

Abstract:Molybdenum is an important strategic rare metal, widely used in steel, chemical, aerospace and other fields. Molybdenite is the most important raw material for molybdenum smelting, and its oxidation roasting process has always been the mainstream process in China and other countries. The molybdenum oxide obtained by roasting is mainly used as an additive in the steel industry and is also the main raw material for the production of ferromolybdenum and ammonium molybdate chemical products. With the increasing consumption of high-quality molybdenite resources, the proportion of low-grade complex molybdenite is getting larger and larger, and the traditional process is facing many problems such as difficult flue gas treatment and low comprehensive recovery rate. Therefore, this paper summarizes the research on molybdenite smelting processes carried out in recent years, such as the addition of additives for roasting, chlorination process, direct reduction process and vacuum thermal decomposition process, nitric acid atmospheric oxidation method, sodium hypochlorite decomposition method, acid-base medium oxygen pressure decomposition method and electro-oxidation decomposition method, analyzes and compares the characteristics of each process, and looks forward to the main development directions of molybdenum metallurgy in the future.

Abstract:With the development of new energy vehicles in the world, the demand for nickel and cobalt resources for ternary lithium-ion batteries has increased, and low-grade laterite nickel ore has become one of the important nickel and cobalt resources. The nickel and cobalt in the laterite nickel ore are mainly in the form of metal oxides, and the metal nickel grade is relatively low. High pressure acid leaching (HPAL) technology processes laterite nickel ores under high temperature, high pressure, and concentrated sulfuric acid conditions, efficiently leaching nickel and cobalt ions and allowing them to enter the solution in the form of sulfates, thereby achieving metal enrichment and purification through neutralization, precipitation, and other processes. The paper analyzes the resources and characteristics of laterite nickel ore, outlines the smelting technologies of laterite nickel ore (HPAL, medium temperature acid leaching/ammonia leaching, rotary kiln electric furnace (RKEF), and rotary kiln direct reduction-magnetic separation (R/S)), analyzes the process principle, technical advantages, and application prospects of HPAL smelting technology, and focuses on analyzing the influencing factors of iron and aluminum neutralization. HPAL technology not only improves the recovery rate of nickel and cobalt, but also reduces the emission of waste gas and wastewater during the smelting process, providing new ideas for the enrichment and extraction of low-grade laterite nickel ore.

Abstract:To efficiently recover selenium (Se) and tellurium (Te) from the copper leaching solution generated by sulfation roasting of copper anode slime, this study aimed to shorten the Te extraction process, enhance Te recovery efficiency, and achieve one-step separation of Se and Te from the slime. A combined process integrating concentration enrichment, sodium sulfite reduction, and hydrochloric acid-catalyzed Te reduction was proposed for Se and Te recovery from the target leaching solution. Experimental results indicated that when the copper leaching solution was concentrated by 3 times, the direct recovery rate of copper reached 67.5%. For Se recovery, a high direct recovery rate of 97.45% was achieved under the optimal conditions: stirring speed of 150r/min, reduction temperature of 80℃, sodium sulfite addition multiple of 2.5, and reduction time of 2h. Regarding Te recovery, the optimal parameters were determined as stirring speed of 150r/min, reduction temperature of 90℃, hydrochloric acid addition multiple of 1.0, sodium sulfite addition multiple of 3, and reduction time of 2h, resulting in a direct recovery rate of 92.62%. In the scale-up experiment, the direct recovery rates of Se and Te were further improved to 98.86% and 93.72%, respectively. By leveraging the stepwise reduction strategy, this process enabled efficient and selective recovery of Se and Te from the copper leaching solution, providing technical support for the resource utilization of copper anode slime with remarkable economic and environmental benefits. Moreover, it offered an innovative approach for the one-step recovery of Se and Te from copper anode slime.

Abstract:The paper establishes a method for the determination of iron content in silicon nitride by inductively coupled plasma atomic emission spectrometry (ICP-AES) after fusion with lithium tetraborate-lithium metaborate. Lithium tetraborate-lithium metaborate is used to dissolve the sample, and the effects of the sample weighing amount and the dosage of the lithium tetraborate-lithium metaborate mixed solvent on the determination results of iron are investigated. The results show that there is a good linear relationship between the mass concentration of the iron standard solution and the spectral intensity, and the correlation coefficient is greater than 0.999. Drawing the calibration curve by the matrix matching method can eliminate the influence of the matrix effect, and the detection limit of iron is 0.0085mg/L. Taking the standard silicon nitride sample JCRM R005 as an example, the relative standard deviation (RSD) of the determination results is 3.12% (n=6), and the measured value is basically consistent with the standard value. The standard deviation of the Fe element determination in the three actual silicon nitride samples was between 2.80% and 3.70%. When this method is used to determine the standard silicon nitride samples, the determination results are within the allowable range of the standard values. The method has the advantages of rapidity, accuracy, high sensitivity, etc., and is suitable for the detection of iron element content in silicon nitride.

Abstract:This study investigates the influence of butterfly valve installation positions on flow characteristics in an inverted U-shaped pipeline system through numerical simulations based on SolidWorks Flow Simulation. By constructing three butterfly valve configurations (downstream of the elbow, upstream of the elbow, and in a straight pipe) combined with flow field visualization and quantitative analysis of flow resistance coefficients, the hydraulic performance of different layouts was systematically compared. The results reveal a significant negative correlation between the valve opening angle and the flow resistance coefficient, with nonlinear resistance modulation by angle variation. The resistance adjustment gradient is particularly pronounced in the low-opening range (0°~30°). When the butterfly valve is installed upstream of the elbow, the system exhibits superior flow stability across the full operating range, with significantly reduced flow resistance coefficients and pressure losses. Additionally, this configuration effectively suppresses valve vibration and flow separation phenomena. Based on the simulation results, it is recommended to prioritize the upstream elbow installation of butterfly valves in engineering practice, especially for pipeline systems requiring frequent adjustments. Further performance improvements can be achieved by optimizing elbow spacing or introducing flow guides.

Abstract:In the process of lithium extraction from old brine, the extraction method has the advantages of high selectivity and high yield in boron extraction from old brine in salt lakes. An extraction experiment was conducted on boron from brine of a salt lake in Qinghai Province, and the extraction mechanism of boron and the optimal extraction and stripping conditions were determined. The research results indicate that the boric acid extraction process is an esterification reaction process, and the esterification reaction between C8H18O and H3BO3 produces a cosolvent, namely 2C8H17O—B—OH. At an acidity pH value of ~1.5 in the extraction solution, the organic phase was composed of 50% isooctanol and 50% sulfonated kerosene. Compared with O/A=1, the concentration of boric acid loaded on the organic phase after a single extraction was 18.08g/L, and the single-stage extraction rate of boric acid was 92.94%. When the actual concentration of loaded organic phase boric acid is 51.49g/L, the stripping rate is 78.06% compared to O/A=1, and the boric acid concentration in the stripping solution is 40.19g/L.The study aims to provide theoretical basis and data support for the industrial design of boron extraction.

Abstract:A copper smelting enterprise in Guangxi faced issues such as low thermal utilization efficiency of its 450t tilting furnace, short service life of refractory bricks in the oxidation-reduction zone (only 7 months), poor operation of the exhaust gas system, and long material-adding and heating cycles (over 16 hours). The study, combining the characteristics of cold material processing technology, proposes a multi-dimensional optimization plan and verifies it through practical implementation.The main technical solutions focus on improving efficiency as follows: 1) implementing material-adding control based on raw material composition, optimizing the division of labor through dual material-adding doors; 2) adding 4 top combustion guns to enhance thermal field uniformity; 3) enabling high-low position switching of oxygen-deficient combustion guns; 4) installing cast copper water jackets for cooling in the oxidation-reduction zone; 5) modifying the exhaust gas system to use copper water jacket flues and adding water-cooled heat exchangers. Through a series of optimized modifications, the service life of the furnace refractory bricks was extended to 11~13 months, thermal utilization efficiency increased by 20 percentage points; the material-adding and heating cycle was shortened by 3.5~4 hours; the exhaust gas system operated smoothly. At the same time, the pass rate of anode plates was improved, slag production was reduced, operational efficiency and production capacity were increased, and maintenance costs were lowered. The study solves the core points of the tilting furnace through synergistic optimization of process, equipment and thermal engineering, reduces energy consumption costs, and provides empirical reference for low-carbon transformation of similar equipment in the industry.

Abstract:Within nonferrous metallurgical industrial parks, substantial amounts of high-temperature flue gas exist. To prevent atmospheric pollution, the waste heat from these flue gases is recovered to generate saturated steam, which is then sent to turbine power stations for energy utilization. The preheating of steam pipelines before steam delivery is termed as “pipeline warming”. Prior to turbine unit startup, the pipelines between the turbine inlet valve and main steam valve require warming. Traditional manual warming operations rely on operators' experience to manually adjust valves, resulting in heavy workloads, low efficiency, and potential operational errors. To ensure safe and systematic automated pipeline warming, the paper proposes an automatic solution: installing control valves, thermal resistors and pressure transmitters in steam pipelines. These components connect to the plants Distributed Control System (DCS) for data acquisition and automated control. The automation implementation can effectively enhance cold-start efficiency of turbine units, reduce manual operations, and protect steam pipelines from thermal stress damage.

Abstract:The paper introduces a control method for the inlet water regulating valve of the heat exchanger in the vacuum swing adsorption (VPSA) oxygen production process. Firstly, it briefly describes the complex characteristics of temperature control in the VPSA adsorption tower, including large lag and sensitivity to environmental temperature. Then, it analyzes the shortcomings of conventional PID control in VPSA temperature regulation and proposes the use of a fuzzy self-tuning PID parameter method. Finally, it is implemented using Siemens 1500 PLC and the WinCC software from ABB. Taking a VPSA device as an example, by adjusting the proportional coefficient, differential action, and integral action, two temperature control curves were obtained. The results show that conventional PID temperature control fluctuates by approximately 10℃ when the environmental temperature changes sharply, and has a large overshoot. Moreover, due to the selection of the integral parameter no longer being applicable, the temperature deviates significantly from the set temperature at night. In contrast, the fuzzy self-tuning PID control responds faster to temperature changes, has an overshoot of 5%, and the temperature curve is closer to the set value and is adjusted promptly. Compared to traditional PID control, the fuzzy self-tuning PID control has a smaller overshoot during extreme temperature changes and a more stable temperature change trend after the heat exchanger.

Abstract:The level of automation in underground drainage systems of non-ferrous metal mines in China varies significantly. Most large and medium-sized mines have basically achieved automatic drainage. The automation level of some small and medium-sized mines is still relatively low, and on-site manual operations are mainly performed. Mines that have implemented automatic drainage also have problems such as low degree of automation，independent control systems and inability to share data. The paper describes the current status of the automation of drainage pump house in non-ferrous mines, and proposes the automation transformation solution of the underground drainage pump house based on the SCADA system, and explains in detail the network structure, detection and control content, water pump startup process, and control methods, etc. After the transformation of the underground drainage system, operators can centrally monitor the operation status of all underground drainage pump rooms from the surface control room. This eliminates the “information silos” between the control systems of the various drainage pump rooms, achieving unattended operation of the drainage system. The operational results after the transformation demonstrate significant cost control effects, with labor costs decreasing from $5000/t of copper to $4000/t, resulting in annual labor cost savings of approximately $700000.

Abstract:The multi-metallic concentrator has long been challenged by highly variable ore properties, frequent manual adjustments, and unstable control in China, which severely constrained both product quality and production efficiency in the grinding circuit. To address these issues, this study developed an intelligent grinding control (IGC) system capable of adaptive optimization, aiming to enhance operational performance and production intelligence. The system leverages a strategy that integrates expert knowledge with data-driven fuzzy control and process logic to achieve precise, multi-parameter, and multi-loop cooperative control with self-adaptive adjustment in the grinding process. After on-site production practice, the IGC system operates stably and reliably, increasing the processing capacity of the raw ore by 3.41%, improving the qualification rate of grinding product concentration by 4.58 percentages, and increasing the qualification rate of grinding product particle size by 3.34 percentages. These outcomes effectively met the plants goals of increasing production quality, reducing labor intensity, and enhancing economic performance. The system provides a reliable technical pathway and a practical reference for the intelligent upgrading of similar concentrator.

Abstract:With the advancement of intelligent manufacturing and smart logistics, traditional factory grab cranes are struggling to meet the requirements in terms of efficiency and safety. This paper constructs a fully intelligent grab crane management system based on automatic driving, artificial intelligence and machine vision. Through intelligent positioning, target recognition and autonomous operation, it realizes intelligent silo management in the material preparation workshop. After the system was applied in a raw material factory, it significantly improved equipment stability and operation accuracy, reduced operating costs, promoted the intelligent upgrading of grab cranes, and provided support for the intelligent transformation of the non-ferrous metallurgy industry.Since the project system was put into operation, the response time for equipment anomalies has been shortened by 60%, and operational efficiency has been improved by 40%, and remote maintenance guidance has reduced on-site maintenance time by 30%, and the equipment failure rate has been reduced by 25%.