Zinc Smelter Research Articles

Making waste profitable: Efficient recovery of metallic iron from jarosite residues

To address the hazardous by-product of zinc smelting and resource utilization of jarosite residue, this study applies an electric field-assisted hot acid treatment to completely recycle Iron (Fe). This innovative approach aims to enhance the leaching efficiency of Fe from jarosite residue. The introduction of electric field changes the charge distribution on the surface of the particles to enhanced ions and electrons exchange and promotes the collision between particles to strengthen reaction kinetics. Based on the above, the leaching efficiency of Fe in jarosite under sulfuric acid attack is improved observably. The result shows that Fe leaching efficiency reaches 98.83%, which is increased by 28% under the optimal experimental conditions: current density of 30 mA/cm2, H2SO4 concentration of 1.5 mol/L, solid-liquid ratio of 70 g/L, temperature of 80 °C and time of 12 h. Leaching kinetics calculations shows that the apparent activation energy is 16.97 kJ/mol and leaching of jarosite residue is controlled by a mixture of chemical reaction and diffusion, temperature and concentration of leaching solution have influence on leaching. This work provides a feasible idea for the efficient leaching Fe from jarosite residue.

Driving factors for distribution and transformation of heavy metals speciation in a zinc smelting site

Heavy metal pollution at an abandoned smelter pose a significant risk to environmental health. However, remediation strategies are constrained by inadequate knowledge of the polymetallic distribution, speciation patterns, and transformation factors at these sites. This study investigates the influence of soil minerals, heavy metal occurrence forms, and environmental factors on heavy metal migration behaviors and speciation transformations. X-ray diffraction analysis revealed that the minerals associated with heavy metals are mainly hematite, franklinite, sphalerite, and galena. Sequential extraction results suggest that lead and zinc are primarily present in the organic-sulfide fractions (F4) and residual form (F5) in the soil, accounting for over 70% of the total heavy metal content. Zinc displayed greater instability in carbonate-bound (16%) and exchangeable (2%) forms. The migration and diffusion patterns of heavy metals in the subsurface environment were visualized through the simulation of labile state heavy metals, demonstrating high congruence with groundwater pollution distribution patterns. The key environmental factors influencing heavy metal stable states (F4 and F5) were assessed by integrating random forest models and redundancy analysis. Primary factors facilitating Pb transformation into stable states were available phosphorus, clay content, depth, and soil organic matter. For Zn, the principal drivers were Mn oxides, soil organic matter, clay content, and inorganic sulfur ions. These findings enhance understanding of the distribution and transformation of heavy metal speciation and can provide valuable insights into controlling heavy metal pollution at non-ferrous smelting sites.

A data and knowledge driven autonomous intelligent manufacturing system for intelligent factories

The non-ferrous metal industry is encountering several challenges, including production efficiency, manufacturing information fragmentation, and human health problems, which highlights the importance of implementing autonomous intelligent manufacturing systems (AIMS). Recently, the foundation model like GPT-4, has garnered attentions due to its exceptional capabilities and proficiency in diverse domains and tasks, facilitating the realization of AIMS. However, the existing foundation models can only address basic general-purpose tasks and are difficult to use for industrial applications. In this paper, we propose a data and knowledge driven AIMS with industrial-generative pretrained Transformer (Industrial-GPT) for intelligent factories. The paradigms and architecture of autonomous intelligent factories are firstly defined. Then, we explore the mechanism with knowledge graph, digital twin, and Industrial-GPT, including multi-level autonomous perception, cross layer and domain cognition, and event-driven collaborative decision-making. Finally, the detailed case study is based on the cooperation with a zinc smelting intelligent factory to achieve networked collaborative manufacturing, and explores the theory and realization mechanism of AIMS on a small scale. We explore the experimental analyses, evaluation mechanisms and platform applications of AIMS at the workshop level. We believe this will help to realize larger scale AIMS in the future.

Application of Oxygen-enriched Side-blowing Technology in Treating Zinc Leaching Residue in China

Zinc hydrometallurgy is the main process of zinc smelting in the world. The leaching residue produced by different hydrometallurgical processes have different components, but they contain valuable metals such as zinc, silver, gold, indium and germanium, and heavy metals such as lead, cadmium and arsenic. In China, leaching residue is defined as hazardous waste, which requires harmless treatment and recovery of valuable metals. At present, China’s main zinc leaching residue treatment technologies include Welz kiln, fuming furnace and Top-submerged lance Smelting furnace. These technologies have been applied for many years and are mature and reliable, but they need further improvement in energy conservation and environmental protection. In recent years, with the continuous progress of China’s smelting technology, the oxygen-enriched side-blowing technology has been successfully applied to the treatment of zinc leaching residue, mainly including the Side-submerged combustion smelting technology of China ENFI and the Vanukov side-blowing technology. At present, the above two side blowing technologies have been put into industrial practice in many zinc smelters in China, which are characterized by low energy consumption, high recovery rate of valuable metals and high sulfur recovery rate. This paper introduces the application of the above two side blowing technologies in China’s zinc smelters, and compares them from furnace structure, production operation, and technical indicators. Oxygen-enriched side-blowing technology will become the mainstream treatment process of zinc residue in China and even in the world in the future.

Recycling potential of secondary zinc materials

Circularity is a decisive corner stone of a sustainable use of raw materials. This has been recognized at global level and is pushed forward specifically in Europe and e.g., Japan. Based on intensive desk top research and interviews with experts from the zinc industry, information on secondary raw materials for zinc recovery was compiled. This paper comprises of an overview of zinc bearing wastes, residues, and by-products occurring in all stages of zinc mining, production, as well as first-use and end-use production. These materials are quantified and characterized, and ways of recycling are described.As a result, potentials for an increase of zinc recycling rates are identified. Mine tailings are a meaningful resource for zinc recovery. Industrial wastes occurring in zinc smelters, such as Jarosite, Goethite, and their likes are in the scope of research projects aiming at recycling zinc and other valuable metals. Residues, ashes, drosses, slags that are produced in first use operation of the zinc value chain, such as galvanizing, zinc die casting, or brass plants are recycled almost completely in Europe and in many other regions in the world. The biggest potential for increasing recycling rates for zinc still lies in steel mill dusts. Also, the majority of zinc die cast parts seem to end up in waste incineration and dump sites. This low end-of-life zinc recycling rate bears room for additional recycling opportunities via an improvement of the intelligent collection and sorting of waste and other innovative recycling processes utilizing residues from waste-to-energy plants.

Production increase of high-grade crude zinc oxide pellets at Shisaka Smelting Co., Ltd.

Shisaka Smelting Co., Ltd. has recovered crude zinc oxide pellets from an electric arc furnace dust (EAF dust) by the Waelz kiln process since 1977. The EAF dust processing line consists of a reduction roasting process, a Waelz oxide washing process, and a drying/calcination process. In late years, about 90,000 tons of EAF dust is processed annually at Shisaka. The recovered zinc is sold to zinc smelters as crude zinc oxide pellets, and the amount of production of the pellets is about 40,000 tons per year. Two types of zinc oxide pellets are produced, and the product for electro-refinery requires high quality, especially in fluorine reduction. Most of fluorine are distributed to the clinker in a reduction roasting process, and others are distributed to the Waelz oxide. Conventionally, high-grade crude zinc oxide pellets were produced by washing the Waelz oxide and by volatilizing and separating fluorine under high temperature operation in a drying rotary kiln. However, formation of accretion in the kiln and damage of the shell and refractories of the kiln often occurred under the influence of high temperature operation, and stable consecutive operation of the kiln was difficult.To improve this situation, the fluorine input was reduced by compounding management of EAF dust in the reduction roasting process, and the material residence time in the drying rotary kiln was extended by reducing rotary speed. These improvements resulted in stable consecutive operation under low temperature conditions and increased production of high-grade crude zinc oxide pellets. To improve this situation, the fluorine input was reduced by compounding management of EAF dust in the reduction roasting process, and the material residence time in the drying rotary kiln was extended by reducing rotary speed. These improvements resulted in stable consecutive operation under low temperature conditions and increased production of high-grade crude zinc oxide pellets.

Copper-cobalt cake as a potential source of germanium

Germanium is an important element used in crucial industry sectors like optical fibers for telecommunication or IR optics for night vision systems. However, its global output is limited. It is estimated that its annual global production is ca. 140 tons. Therefore, many world economies, including USA and EU, consider it as a critical raw material. One of the potential sources of germanium is zinc metallurgy. It is assumed that only 3% of germanium present in processed zinc ores is recovered. It was found that during the technological processes of Polish zinc smelters some by-products containing elevated germanium concentrations are produced. In the paper, potential germanium sources, including copper-cobalt cake obtained during the purification of zinc electrolyte and dross from the feeding furnace, are presented. The main components of the cake are cadmium, zinc, copper, nickel, cobalt, and lead, while the dross contains mainly zinc (>65%). Results of leaching tests for both materials using aqueous sulfuric acid solutions are shown. In the case of the cake, wet and dried material was investigated. It was found that the germanium leaching yield for the dried material reached 99%, while for the wet one was 46-86%, depending on leaching conditions (without or with oxidant). On the other hand, the germanium leaching yield for the dross reached 55%. Further processing of the solutions obtained after germanium leaching from the copper-cobalt cake was also analyzed. Two ways were proposed, including precipitation with tannic acid and solvent extraction with addition of complexing agents using a trioctylamine extractant.

Study on Optimization of Deep Purification Process Design of Zinc Oxygen Pressure Acid Leaching Solution

According to the characteristics of high impurity content and complex composition of oxygen pressure leaching (OPL) solution of zinc sulfide concentrate, combined with the quality requirements of large plate electrowinning and automatic plate stripping, the advanced purification process of solution was designed. Through the deep purification process consisting of neutralization indium precipitation and low iron purification, high temperature antimony salt nickel and cobalt removal, copper slag chlorine removal, low temperature zinc powder replacement copper and cadmium removal, fine purification, calcium and magnesium removal, the contents of harmful impurities such as iron, indium, copper, cadmium, nickel, cobalt, fluorine and chlorine in the solution are strictly controlled to ensure that the quality of the deeply purified zinc sulfate solution is qualified and can meet the needs of continuous and stable production. The energy-saving effect of advanced purification process is obvious, and the average DC power consumption per ton of electric zinc is 2880kWh, reaching the advanced level of the same industry in China. The good effect of advanced purification process ensures the successful application of OPL and large plate zinc electrowinning, and improves the technology and equipment level of zinc smelting industry, which has important popularization and application value.

Design and production practice of large fluidized roasting furnace

With the expansion of the scale of zinc smelting enterprises and the progress of new equipment and technology, 152 m2 fluidized roasting furnace has been developed and applied to industrial production, with a single unit capacity of 150,000 to 170,000 tons of electrolytic zinc per year. This paper analyzes and introduces an engineering example of zinc concentrate treatment by a dual-series fluidized roasting furnace. The project was designed by China ENFI Engineering Corporation and put into operation in Hunan province of China in 2018. This paper firstly describes the process flow and main equipment of the preparation system, roasting furnace system, waste heat utilization system, dust collection system from a design perspective. Then, based on production practice, it analyzes and compares aspects such as furnace operation, actual production data, major technical and economic indicators, and the characteristics and optimization of the roasting system equipment. Finally, it is concluded that the dual-series large-scale fluidized roasting furnace has stable production, good product quality, less investment, and fewer labor requirements, which brings good economic benefits to the enterprise. Its operational experience has accumulated parameters and experience for the development of larger roasting furnaces in the future.

Volatilization Kinetics of Zinc from the Flotation Products of Low-Grade Lead–Zinc Oxide Ore during Carbothermic Reduction

Zinc extraction from oxide ore has been paid more and more attention to due to the exhaustion of zinc sulfide ore resources. In this work, the volatilization kinetics of Zn from the flotation products of low-grade lead–zinc oxide ore during carbothermal reduction in the temperature range of 900–1300 °C were investigated. The phase transformation in briquettes during the reduction process was investigated by XRD and EPMA. The results showed that the transformation of ZnS by CaO may begin within the temperature range of 900–1050 °C, with the main occurrence observed in the range of 1050–1250 °C. The kinetics behavior of Zn volatilization was associated with the phase transformation. The volatilization of Zn was controlled by the interfacial chemical reaction within 900–1150 °C. As the reaction proceeded, the generation of the product layers (CaS, FeS and new slag phase) impeded the internal diffusion of Zn, CO and CO2. At this time, internal diffusion served as the rate-controlling step for Zn volatilization in the range of 1150–1300 °C. Hence, a staged kinetics model of Zn volatilization during carbothermal reduction in the form of carbon-bearing briquettes was established, and the apparent rate constants (k(T)) and activation energies (Ea) were obtained. This work provides a scientific basis for the flotation products treatment by carbothermal reduction and is of great significance in improving the sustainability of resources in the zinc smelting industry.

Screening of Maize Varieties with High Biomass and Low Accumulation of Pb and Cd around Lead and Zinc Smelting Enterprises: Field Experiment

In the long-term production process of lead and zinc smelting enterprises, atmospheric subsidence leads to the accumulation of heavy metals in surrounding farmland, which poses a serious threat to the growth of crops and food safety. Given the knowledge that heavy metal pollution in cultivated land does not support treatment and restoration, determining how to ensure the quality and safety of agricultural products is the main problem facing the agricultural industry at present. Previous studies have mainly focused on the low accumulation of heavy metals in maize varieties, while the removal of heavy metals from soil through high biomass has been studied less. In order to identify the maize varieties that demonstrate high removal and low accumulation of heavy metals, 29 maize varieties were planted in soil contaminated with lead (Pb) and cadmium (Cd), and the growth status of the maize varieties and the absorption and transport of Pb and Cd by different tissues were studied. The results showed that heavy metals had the least effect on the growth of the Longhuangbai3, Jinqiuyu 35, Jinyi 418, and Qiuqing 88 varieties, and the content of Pb and Cd in maize varieties was in the order leaf > stem > root > grain. It was found that soil remediation and safe production can be taken into account in the results of the Qiuqing 88 (Pb, Cd), Fengdeng 2025 (Cd), and Yayu 719 (Pb, Cd) varieties. Moreover, the Xinzhongyu 801 (Cd) and Longdan 1701 (Pb) varieties demonstrated high metal accumulation in the edible part, which poses a potential risk to human health; thus, they are not recommended for local cultivation.

Source analysis and contamination evaluation of potentially toxic elements in soil in typical high geological background areas at the county scale in northeastern Yunnan, China

The pollution risk of potentially toxic elements (PTEs) in soil is a common concern in the fields of environmental science and agriculture. The spatial distribution characteristics, pollution risk assessment and genetic sources of PTEs in soil in high geological background areas are crucial to the safe use of land. Based on the data for five PTEs in 921 surface soil samples from typical high geological background areas in SW China, we discuss their spatial distribution characteristics using geostatistics, the semivariance function and its model. We carry out pollution risk assessment using the influence index of comprehensive quality (IICQ) and analyse their genetic sources using the UNMIX receptor model. The spatial distribution of element content has a high spatial coupling with the stratigraphic spread, which is affected by external random factors, resulting in a weakened autocorrelation. The IICQ indicates that soil is dominated by mild and moderate pollution, accounting for 42.24 and 44.95%, respectively, with cadmium contributing up to 63.00% to the IICQ. Chromium and cadmium are controlled by natural sources, accounting for 83.98 and 69.39%, respectively. Arsenic and mercury have anthropogenic sources, accounting for 68.7 and 44.0%, respectively. Lead is controlled by both lead–zinc mining and geological background, accounting for 47.7 and 36.4%, respectively. The UNMIX model demonstrates that the spatial variability of PTEs is influenced by anthropogenic factors, such as coal combustion emissions, which account for 30.1% of the pollution sources. Soil parent material sources contribute 49.4%, followed by lead–zinc mining and smelting activities at 20.5%.

Optimizing the dewatering performance of zinc smelting iron Slag: Investigating the influence of ultrasonic Time, ultrasonic Power, and Liquid-Solid ratio using response surface methodology

Iron slag, a byproduct of the wet zinc refining process, contains a substantial amount of valuable metals such as iron and zinc, making it highly valuable for comprehensive recovery and reuse. However, before recovery, the iron slag requires dehydration pretreatment. The water content in iron slag remains relatively high and difficult to remove even after pressure filtration, leading to extended drying times, reduced drying efficiency, and increased energy consumption. This study explores a novel ultrasonic pretreatment process for iron slag. Using the response surface methodology, we investigated the effects of ultrasonic power, ultrasonic time, liquid-to-solid ratio, and their interactions on the water content, capillary suction time (CST), and filtration resistance of the slag. Regression equations were established to predict the relationships between the water content, CST, filtration resistance, and the various factors. The optimal process parameters were determined as an ultrasonic power of 60 W, ultrasonic time of 22 s, and a liquid-to-solid ratio of 4:1. Under these conditions, the dehydration performance of the iron slag was optimal. The measured values closely matched the predicted values, demonstrating the reliability of the model and the feasibility of the optimized process. Our study of the mechanism of ultrasonic action on iron slag found that under the influence of ultrasonic waves, the particle size of the slag significantly decreased, and the particle morphology changed. Compared to conventional drying, the drying rate of the iron slag after ultrasonic pretreatment was accelerated, and the drying time was reduced.

Health Risks for Consumers of Forest Ground Cover Produce Contaminated with Heavy Metals.

The activity of heavy metal (HM) mining and processing industries causes soils contamination with HM. The metals could be transferred from contaminated soils to edible plants and fungi. This study aimed to assess the content of Cd, Pb, Hg, As, and Ni in berries and edible mushrooms collected in the forests located near Miasteczko Slaskie zinc smelter and in the Lubliniec region, in the context of consumers' health risk. The ET-AAS method was used to determine the content of Cd, Pb, Ni, and As. Mercury concentration was determined using the CV-AFS method. The studies showed high levels of Cd and Pb in the examined products. A statistically significant impact of the distance from the smelter on the Cd concentration in the berries was observed. Total non-cancer health risk from the combined exposure of adults to all HM in mushrooms and berries was significant when consuming the most heavily contaminated produce. The risk to children was significant, even when consuming products with moderate levels of the metals. Ingestion of Cd by children with mushrooms was related to a high cancer risk. The uncertainty of the results was determined. It is recommended to take action to increase awareness among residents of the areas adjacent to the forests regarding the existing health risk and to take possible measures to reduce exposure to HM.

Assessment of Atmospheric Deposition of Potentially Toxic Elements in Macedonia Using a Moss Biomonitoring Technique

This study aims to investigate the changes in atmospheric deposition trends in Macedonia, using a moss biomonitoring technique. This technique has been used to assess the content of potentially toxic elements in Macedonia in 2002, 2005, 2010, and 2015, within the framework of the International Cooperative Program on Effects of Air Pollution on Natural Vegetation and Crops. The content of 42 elements was analyzed using instrumental neutron activation analysis (INAA), inductively coupled plasma–atomic emission spectrometry (ICP–AES), and atomic absorption spectrometry (AAS), on 72 moss samples collected in the summer of 2015. The median values of the elements studied were compared with data from previous years and with median values obtained from comparable studies in Norway and the neighboring countries. Through factor and cluster analysis, three geogenic factors were identified: Factor 1, which includes the elements Al, Ce, Fe, Hf, La, Li, Na, Sc, Sm, Tb, Ti, Th, V, and U; Factor 4, which includes As, Cl, and I; and Factor 5, which includes the elements Ba and Sr. In addition, one geogenic-anthropogenic factor containing Co, Cr, and Ni (Factor 2), was identified, and one anthropogenic factor containing Cd, Pb, Sb, and Zn (Factor 3). The lead and zinc mines near the towns of Kriva Palanka, Probištip, and Makedonska Kamenica in the eastern region of the country, the former lead and zinc smelter in the town of Veles, and the ferronickel smelter near Kavadarci, have continuously had the greatest anthropogenic impact on the atmospheric deposition of potentially toxic elements during the time period of the study. In addition to the human influences, the lithology and the composition of the soil continue to play a significant role in the distribution of the elements.

CFD-based burner parameter optimization of a sintering ignition furnace

To clarify the influence of burner parameters on the ignition process, this paper focuses on the ignition furnace of the lead–zinc smelting sintering process in ISP. A CFD-based optimization study of burner parameters in the sintering ignition furnace was implemented based on the ignition process, including the inclination angle and inter-burner distance of ignition burners, the airflow outlet area and arrangement of main burners. The results show that enlarging the inclination angle of ignition burners can improve the average temperature and temperature uniformity of ignition section, whereas an excessively large angle could deteriorate the uniformity. The temperature uniformity of the ignition section can be improved by decreasing the inter-burner distance of ignition burners, its average temperature will be reduced. For the main burners, increasing their airflow area can effectively adjust the flame length, thereby improving the temperature distribution in the ignition section. In addition, both the “6 + 7” staggered arrangement and the “7 + 7” uniform arrangement of main burners contribute to an elevation in the average temperature and temperature uniformity of the ignition section, with the latter showing better performance.

Groundwater Quality Assessment in the Area of the Zinc Smelter in Miasteczko Śląskie (Poland) Using Selected Metal Indices

Groundwater quality assessment in the region of potential pollution sources can be performed through the use of index-based methods. The aim of this paper was to present the results of the groundwater quality assessment in the region of the zinc smelter in Miasteczko Śląskie (southern Poland) for the Quaternary aquifer based on monitoring data from 2000, 2011, and 2022. The following parameters were used in the analysis: Pb, Cd, Ni, Cu, Fe, Mn, and Zn. Three indices were calculated, i.e., the landfill water pollution index (LWPI), heavy metal pollution index (HPI), and metal index (MI). The values of the indicators suggest that in the described study area, there are waters that are under the strong influence of the zinc smelter infrastructure and landfills. The highest values obtained are about 17 for LWPI, about 66 for HPI, and about 133 for MI. These values indicate significant anthropogenic pollution of the groundwater of the Quaternary aquifer in the study area. Taking into account the values obtained for all three indices, it can be concluded that the HPI indicator is the least reliable due to the need to select two limit values (background and ideal content in waters for each of the parameters), which would suggest that in some cases, waters are not very contaminated. The other two indices show similarities (mainly in their spatial distribution), and only the choice of parameters determines which of the indices should be used. A comparison of the results of local groundwater quality monitoring with the results of the calculated indices indicate that the values of the calculated MI indices are closest to the actual water quality status.

Selective separation of zinc from germanium-bearing iron cake via a roasting–leaching process

Germanium-bearing iron cake (GBIC) produced through the germanium removal process in a zinc smelter is a valuable source of zinc and germanium. However, achieving selective separation of zinc and germanium using pyrometallurgy treatment and sulfuric acid leaching methods is challenging. To address these challenges, this study introduced a novel roasting–leaching process. During roasting, willemite transformed into ammonia-soluble hemimorphite, promoting zinc leaching. This transformation was mainly attributed to the reaction between in situ water in GBIC and willemite within 200–500 °C. Optimal roasting conditions included a particle size range of 49–74 µm, a roasting temperature of 490 °C, and a duration of 4 h. Under optimized leaching conditions—[NH4++NH3] (7 mol/L), NH4+/NH3 molar ratio (2.5), temperature (50 °C), liquid-to-solid ratio (20 mL/g), agitation speed (600 rpm), and time (180 min)—zinc and germanium exhibited leaching yields of 84.92 % and 0.59 %, respectively, in an ammonia–ammonium carbonate system. After three cycles of leaching, the Zn concentration in leachate increased to 20 g/L, facilitating the subsequent recovery of zinc. Moreover, the Ge concentration in the germanium-bearing leaching residue increased by 1.5 times compared with the initial GBIC, making the residue a valuable source of germanium.

Study on the Drying Kinetics of Zinc Smelting Iron Slag Assisted by Ultrasonic Waves.

This study investigates the impact of ultrasonic treatment on the drying kinetics of zinc smelting iron slag. Through the Arrhenius equation, it was found that the reaction order of zinc smelting iron slag remains constant at 1/2 before and after ultrasonic treatment, indicating a proportional relationship between the reaction rate and the square root of the reactant concentration. Despite the increased drying rate of the iron slag due to ultrasonic pretreatment, the reaction order remains at 1/2. Additionally, it was observed that the drying kinetics of untreated iron slag aligns with the Wang and Singh model, while the drying kinetics of ultrasonically pretreated iron slag fits the Page model. The Page model facilitates the prediction of drying rate and drying time for ultrasonically pretreated iron slag, enabling the optimization of the drying process, enhancing efficiency, and comparing drying performance under different conditions. Using ultrasonic pretreatment, the subsequent drying process of iron slag can significantly shorten the time and save energy. These findings provide essential theoretical foundations for optimizing the drying process of zinc smelting iron slag.

Roasting temperature distribution control using multi-agent reinforcement learning

As the initial stage of the zinc smelting process, the roasting process plays an important role in the entire smelting process. The temperature distribution in the roasting process directly determines final product quality, production efficiency, and operation safety. Due to the fact that the roasting temperature often shows nonlinear and spatial-temporally varying dynamics, the process control of such a complex dynamic temperature field is challenging. This paper proposes a new approach employing multi-agent reinforcement learning to facilitate roasting temperature distribution control. First, state, action and reward are defined for the roasting process to formulate the roasting process as a Markov decision process (MDP). Then, to enhance the robustness of the reinforcement learning (RL)-based controller (exploration capability), we propose a multi-agent deep deterministic policy gradient (multi-DDPG) algorithm. The proposed method and the baseline method were run independently for several times via simulation case study. By comparing the overall performance and the worst performance, multi-DDPG showed more stable performance. In the future, it may be possible to achieve temperature distribution control for real roasting processes.