Coal Washing Research Articles

Optimization of key link parameters and mechanism of the jet-stirring synergistic column flotation method

In recent years, with the deepening of the degree of coal mining and the improvement of the mechanization and intelligent level of coal dressing, the proportion of fine and micro-fine coal production has been increasing. Micro-fine grade separation has gradually become an important research direction in coal washing industry. This paper is based on a novel jet-stirring synergistic column flotation method, which integrates jet-impact mixing, impeller mixing, and dispersion into the structure of a column flotation tank. By combining with existing research foundations, we construct a corresponding physical model and conduct optimization studies on key parameters related to jetting, impeller mixing, and mechanism. The resulting fundamental theory provides clear insights for the engineering application of this innovative flotation technology. The effects of jet-stirring synergy on bubble adsorption and reagent adsorption were studied, and the flotation effect of the new flotation technology was experimentally verified, laying a theoretical foundation for the industrial application of the device.

Application of coal-based solid waste artificial soil in the restoration of saline alkali land-taking the saline alkali land restoration of the Emao River in China as an example

In this paper, coal-based solid waste, including fly ash, desulfurization gypsum, furnace bottom slag, and coal washing sludge in the ratio of 3:2:3:2 with a total of 200 tons/0.07 hm2, were used as the specialized main material for restoring the saline alkali land of Emao River in Huairen of China. The remediation effect and safety of solid waste artificial soil were evaluated by testing the soil samples before and after the remediation. The results showed that the pH value of the soil after remediation decreased from 9.98 to 7.60, which was close to the neutral value and suitable for crop growth. The total amount of water-soluble salts decreased from 8.30 g kg−1 to 4.80 g kg−1 with a decrease of 42.2 %. The organic matter increased from 6.5 g kg−1 to 39.1 g kg−1 with a 5-fold increase. Compared to the original soil, the heavy metal content in the restored soil did not increased, but instead decreased, indicating that the restoration technology was feasible and meets environmental requirements. Corn planting experiment results showed that corn's emergence rate in the original saline alkali soil was extremely low (about 1 %), while in the restored soil reached over 99 %. The average yield of corn in restoration field was 16.56 % higher than the average local yield level. The residual content of heavy metals and organic toxic substances in corn and potatoes grown on restored soil were analyzed, and the results showed that the detected heavy metal content was far lower than the standard values, and the residual organic toxic substances were basically not detected, indicating that the agricultural fruits grown on restored soil were safe, harmless, and edible. This approach could achieve large-scale consumption of coal-based solid waste, increase arable land, and reduce the cost of restoring saline alkali land.

Design and application of coal gangue sorting system based on deep learning

With the advancement of science and technology, coal-washing plants are transitioning to intelligent, information-based, and professional sorting systems. This shift accelerates the construction a modern economic system characterized by green and low-carbon development, thereby promoting the high-quality advancement of the coal industry. Traditional manual gangue picking and multi-axis robotic arm gangue selection currently suffer from low recognition accuracy, slow sorting efficiency, and high worker labor intensity. This paper proposes a deep learning-based, non-contact gangue recognition and pneumatic intelligent sorting system. The system constructs a dynamic database containing key feature information such as the target gangue's contour, quality, and center of mass. The system elucidates the relationships between ejection speed, mass, volume, angle of incidence, and the impact energy matching mechanism. Demonstration experiments using the system prototype for coal gangue sorting reveal that, compared to existing robotic arm sorting methods in coal washing plants, this system achieves a gangue identification accuracy exceeding 97%, a sorting rate above 91%, and a separation time of less than 3 s from identification to separation, thereby effectively enhancing raw coal purity.

Hydration mechanism of limestone calcined clay cement containing calcined coal gangue

Coal gangue (CG), a byproduct of coal washing and mining, has experienced a substantial increase in production in tandem with rising energy consumption trends. The utilization of calcined CG as an additive to cementitious materials is considered a potentially effective strategy for CG management and expanding its applicability on a large scale. This research investigates the impact of calcined CG on the characteristics of blended cements by applying isothermal calorimetry, X-ray diffraction (XRD), Mercury Intrusion Porosimetry (MIP), and mechanical assessments. This paper investigates four separate binder systems: Ordinary Portland Cement (OPC), OPC incorporating 30 % calcined CG, OPC with 15 % limestone addition, and limestone calcined clay cement (LC3). The XRD analysis of the hydrate phase assemblage indicated that the hydrates in LC3 systems exhibit a notable increase, consequently leading to a significant reduction in porosity by MIP results. Furthermore, LC3 systems show greater refinement in pore structure compared to other blended cements. These findings present novel opportunities for furthering the utilization of coal gangue and extending the applications of LC3 cement.

Sustainable bioleaching of heavy metals from coal tailings using Bacillus inaquosorum B.4: Mechanistic insights and environmental implications

Coal tailings are byproducts of the coal washing process and pose significant environmental pollution issues due to the release of heavy metal elements. In this study, a sustainable bioleaching method was proposed, and a Bacillus inaquosorum B.4 strain with high Extracellular Polymeric Substances(EPS) production characteristics was isolated through mutagenesis. The importance of EPS in the adsorption of free heavy metals was validated, as EPS-covered (EPS-C) cells exhibited significantly higher removal rates of Cu (71.30 ± 1.10 %), Pb (79.90 ± 1.02 %), and Zn (64.90 ± 1.00 %) compared to EPS-removed (EPS-R) cells. The adsorption kinetics followed pseudo-second-order kinetics models. The significant bioleaching efficiency of this strain for heavy metals Pb, Zn, and Cu in coal tailings was investigated. Through shake flask experiments under conditions of a particle size of 45–74 μm, pH of 7, and a bacterial concentration of 15.00 %, the bioleaching rates of Pb, Zn, and Cu were found to be 91.88 mg/kg、23.21 mg/kg、8.06 mg/kg, respectively. The B.4 strain's mechanism of action was determined using techniques like SEM, XRD, FT-IR, and LA-ICP-MS. It involves absorbing organic compounds, disrupting the lattice structure of heavy metal minerals, and releasing metal ions. These metal ions are then immobilized by forming complexes with functional groups on the bacterial surface. The bioleaching process was primarily subject to a combination of chemical reaction and diffusion control. This research offers a practical bioremediation strategy to manage heavy metals in coal tailings and has important implications for environmental protection and sustainable resource utilization.

Effect of PAM on Surface Hydrophobicity of Montmorillonite and Difference of Interface Adsorption: An Experimental and Simulation Study.

How to realize efficient treatment of coal slime generated by a coal washing operation is an urgent problem to be solved in this industry. The presence of clay minerals, especially highly hydrophilic montmorillonite (MMT), is the key to the poor treatment effect of coal slime. Polyacrylamide (PAM) is very popular as a polymer agent to improve the treatment of coal slime. However, when it is used to treat coal slime with a high content of MMT, the selection of PAM type and the mechanism of action are still lacking. In this study, the effects of different types of PAM on the treatment of coal slime water containing MMT are considered by sedimentation and press filtration tests. The interaction mechanism of PAM on the MMT surface is studied by using ζ-potential, Brunauer-Emmett-Teller (BET) analysis, low-field nuclear magnetic resonance, density functional theory (DFT), and molecular dynamics (MD) simulations. The results show that the three PAM can improve the sedimentation and filtration effect of coal slime water, and the performance is CPAM > NPAM > APAM. The ζ-potential of the MMT (001) surface increases under the action of three PAM, and the effect of CPAM is the most significant. The adsorption of PAM on the MMT (001) surface has the ability to neutralize the surface charge of MMT. The flocculation of MMT particles under PAM results in an increase of particle size and a decrease of specific surface area. Meanwhile, the pore volume of MMT decreases, and the average pore size increases. In addition, PAM mainly removes vicinal water on the MMT surface. The active sites of the MMT surface and PAM are calculated by DFT. The adsorption of three PAM structural units on the MMT Na-001 surface and non-001 surface is nonbonding interaction, and the adsorption energy of CPAM is the largest. And the left shift of εp of the O atom on the MMT surface is conducive to the stable adsorption of CPAM. The MD results show that the concentration of water molecules on the surface of MMT Na-001 decreases after PAM is adsorbed on the MMT Na-001 surface, indicating that PAM can keep water molecules away from the surface of MMT, which means that the hydrophobicity of the MMT surface is enhanced. This study has guiding significance for the selection of PAM and the development of new flocculants in the treatment of coal slime with a high content of MMT.

Industrial fluoride emissions and their spatial characteristics in the Nansi Lake Basin, Eastern China.

Excessive fluoride emissions threaten ecological stability and human health. Previous studies have noted that industrial sources could be significant. However, quantifying industrial fluoride emissions has not been yet reported. In this study, both bottom-up and top-down approaches were used to estimate the fluoride emissions in the Nansi Lake Basin. Global and local spatial autocorrelation were adopted to reveal the spatial agglomeration effects. The fluoride emissions calculated by the bottom-up approach were larger than those calculated by the top-down method. The highest fluoride input mainly occurred in Zoucheng and Mudan. The highest fluoride emissions mainly occurred in Zoucheng and Rencheng using the bottom-up approach. The highest fluoride emissions mainly occurred in Zoucheng and Yanzhou using the top-down approach. Mining and washing of bituminous coal and anthracite (BAW) was the most significant source of fluoride input and emissions. A significant spatial agglomeration effect of fluoride emissions was found. These findings could provide a method for accurate industrial fluoride emission estimation, complement the critical data on the fluoride emissions of main industrial sectors, and provide a scientific basis for tracing fluoride sources.

Numerical simulation of the dust pollution characteristics and the optimal dustproof air volume in coal washing plant screening workshop

Dust pollution generated during the working process of a screening workshop in a coal washing plant seriously threatens the occupational health of workers. To improve the working environment for workers, we investigated the effects of various airflow parameters on the diffusion of dust particles and pollutants. We established a proportional model of the screening workshop and conducted spatiotemporal analysis of the evolution laws of airflow and particulate matter. We used numerical simulation and on-site measurements to obtain the optimal dust removal air flow rate in a coal washing plant workshop. When the air flow rate is between 360 and 1260 m³/min, the overall dust concentration in the workshop and the average dust mass concentration in the breathing zone decrease significantly as the air flow rate increases. However, if the air flow rate is too high, this can cause re-entrainment of dust, which will pollute the operation area again. The optimum dust removal airflow for the inlet air was 1260 m³/min. This air flow rate decreases the dust at the height of the breathing zone in the working area, and the dust concentration at the sidewalk in the working area decreases by 58.82%. This air flow rate can act as a reference value for workshop ventilation design to provide a clean and safe production environment for coal miners. Our methodology and results are of value the formulation and development of effective dust control and clean production technologies.

Deep Reinforcement Learning and Auto-Differential Evolution Co-Guided Coal Washing

Background. Coal washing is a complicated process and difficult to control, which has many controlling parameters with strong coupling relationship. It is still a challenge to realize the self-perception, self-adjustment, and self-evaluation of coal washing machine, improve the quality of coal washing, ensure production safety, and reduce labor cost. Methods. Through the intelligent transformation of jig, this paper proposes an intelligent washing method with cooperated deep reinforcement learning and evolutionary computation. First, it designs a fault warning method based on statistical analysis, helping to recover the normal running state of jig with manual maintenance. Then, it constructs a regulation strategy generation method with deep reinforcement learning supported by the fusion of artificial experience and historical data. Last, for the lack of monitoring data caused by poor communication quality and environment, the regulation strategy prediction method with evolutionary computation and surrogate model is proposed. Results. In practice, this method shows accurate fault warning accuracy and rapid cleaned coal ash adjustment response ability. Conclusions. This shows that the method proposed in this paper is of great significance for intelligent washing and can better cope with the special situation when the washing equipment sensing data are missing.

Study of Road Performance and Curing Mechanism of Coal Gangue by Curing Agent

Abstract Coal gangue is a type of rock waste product with dark gray color during coal mining and washing. The curing agent stabilizes soils by improving their physico-mechanical properties, allowing the soils to be reused in engineering as the subgrade fill. This study investigates the impact of SAHP curing agent on road performance parameters of coal gangue. The results showed that the road performance parameters of coal gangue increase with the curing agent content. The compressive resilience modulus of 7 days and California bearing ratio of coal gangue with 0.2% curing agent meet the specifications. The scanning electron microscope reveals the presence of agglomerated gels and hexagonal prism crystals between coal gangue particles. The observed crystals are ettringite, and the gels are silicate gel (nSiO2·mH2O) formed by the reaction of Na2O·nSiO2 with CO2 and H2O, as determined by combined X-ray diffraction and energy spectrum analysis. The improved coal gangue by the curing agent can be utilized as subgrade fill, supporting the reuse of coal gangue in highway engineering.

Power Systems and Power Electronics using the DEMATEL Method

Energy and research on energy systems places a focus on all facets of electrical energy, as well as innovation in energy production and delivery, alternative resources, and efficient devices. Systems and equipment for converting, providing, and utilising energy as a kind of electricity are the subject of research initiatives. Power electronics are now a more integral part of power systems, enhancing quality and efficiency and fostering the gradual materialization of intelligent, efficient energy. Many different types of power electronics exist in power systems. The architectural study of changing electrical transformed from one medium to another is known as power electronics. Fields such as electronics reprocess or recover more than 80percent of the entire of the electricity produced at a world average rate of 3.4 billion kilowatts per hour each year. Power electronics converters, sometimes referred to as power converters or switching converters, are used to process or convert electrical energy. Electricity comes in two flavours: AC power and DC power. The distribution system is divided into AC distribution systems and DC distribution systems based on the type of power it uses. Power system analysis is an essential part of electrical power system design. Calculations and simulations are performed to verify that the electrical system, including the system components, is properly specified to perform as planned, withstand the expected stress, and be protected from failures. Advantages of Power Electronics: High power density electricity. Improved efficiency up to 99% in energy conversion. Because to its efficiency and dependability, switching power supply are also being used in medical devices with acoustically sensitive applications. Power system reliability, in general, relates to problems like service interruption and power outages. This is frequently described as a goal to try relying on codes specifically relevant to the consumer. SAIFI, SAIDI, and CAIDI are common dependability index values for US applications. DEMATEL (Decision Making Trial and Evaluation Laboratory) They are divided into analysis using the Nonmetal mineral product industry, General equipment manufacturing, Mining and washing of coal, Textile industry, Food manufacturing industry It is the interaction between the factors Visualized and assesses dependent relationships Through the structural model Also deals with identifying important. Power Electronics in Power Systems, Power Electronics in Transportation Systems, Energy Conservation, Heating & Lighting Control and Renewable Energy Integration Power Systems and Power Electronics in Power Electronics in Power Systems is got the first rank whereas is the Energy Conservation is having the Lowest rank. Power Systems and Power Electronics in Power Electronics in Power Systems is got the first rank whereas is the Energy Conservation is having the Lowest rank.

Dynamic Analysis on Carbon Metabolism of the Northern Region of China Under the Background of Carbon Emission Trading Policy

The launch of the national carbon emissions trading market in China is a policy to carry out the Beautiful China initiative and to establish a low-carbon economic development system that promotes carbon emission and waste reduction. In order to detect the carbon metabolic processes of the pilot and nonpilot municipalities or provinces in the northern region of China， the theory of urban carbon metabolism and the methods of input-output analysis and ecological network analysis were introduced and used. The results showed that the direct carbon emissions of Beijing and Tianjin had decreased， but their embodied carbon emissions had increased since 2012. The direct and embodied carbon emissions of the pilot sectors in Beijing and Tianjin had the same trend； specifically， the emissions of the sectors of mining and washing of coal， extraction of petroleum and natural gas， and manufacture of non-metallic mineral products decreased significantly， but the sectors of production and supply of electric power and steam with high carbon emission increased. The same trend of the embodied carbon emission intensities of sectors with that of their embodied carbon emissions verified that the embodied added values were not growing with the promotion of the carbon emission trading market. Subsequently， the embodied carbon emission of the pilot sectors in all the municipalities and provinces of the northern region were all contributed mainly by the emissions embodied by a path length less than 6； therefore， it showed that more attention should be paid to the trade among sectors with a path length less than 6 and reducing their carbon emissions. Furthermore， from 2007 to 2012， products or service trading among sectors mostly concentrated on sectors within one municipality or province， and these products or services had the characteristics of low carbon emission. Since 2012， the integration development of the Beijing-Tianjin-Hebei urban agglomeration and the new regional economic patterns established in the northern region both promoted the trading across provinces and across sectors. This research is based on the background of the carbon emission trading policy and aims to build a methodology to identify the key actors and paths in a metabolic system. This could provide a scientific basis for regional policy implementation and regional long-term sustainable development.

China’s cross-regional carbon emission spillover effects of urbanization and industrial shifting

With rapid urbanization and industrial shifting in China, demographic and industrial relocation leads to cross-regional carbon emission spillovers, which are playing an increasingly important role in regional carbon transfer and growth. However, how urbanization and industrial shifting influence carbon spillover still needs to be clarified. In this study, we use multi-regional input-output (MRIO) and scenario analyses to investigate the carbon spillover effects of urbanization, industrial shifting, and their synergy effect on provincial and sectoral carbon emissions in China during 2012–2017. The results showed that urbanization in China further increased carbon spillover in the provinces that already have a high spillover. Industrial shifting, as represented by cross-regional trade between sectors, drove changes in cross-regional carbon spillovers and significantly increased the spillover from Henan, Guangdong, and Hebei by 57.7, 29.9, and 23.6 Mt, respectively. By contrast, the synergy effect of urbanization and industrial shifting on carbon spillover was smaller than their separate effects, with Shandong having the highest increase about 0.61 Mt. Furthermore, at the sectoral level, the production and distribution of electricity and heat-power (PEH), smelting and processing of metals (SPM), and mining and washing of coal (MWC) sectors transmitted the largest carbon emission spillover effects among regions. Based on these findings, more fine-grained policy suggestions for assigning responsibility for carbon reductions and mitigation measures at the regional and sectoral levels in the context of urbanization and industrial shifting.

Effects of environmental information disclosure on the green development of mining industry: Evidence from Chinese provincial mining sub-sectors

How environmental information disclosure (EID) affects green transformation of mining industry (MI) is still unknown. Based on the panel data of China's provincial mining sub-sectors, this study explores the effects of EID on the green total factor productivity (GTFP) of China's mining sub-sectors and its influence mechanism. The research shows that EID exerts an inverted U-shaped influence on the GTFP growth of MI, implying that reasonable EID facilitates the green transformation of China's MI, while excessively EID requirements may be counterproductive. The above conclusion still holds after considering the endogeneity and conducting a series of robustness tests. Further analysis shows that the impact of EID on the GTFP of MI has a lag and long-term, and the current EID affects its future GTFP. Meanwhile, EID has a more remarkable effect on the GTFP of the MI in the eastern and central regions and the mining and washing of coal (S3) and extraction of petroleum and natural gas (S4). Mechanism analysis reveals that EID affects the GTFP of the MI through technological innovation, but due to the ‘black expected effect’, EID is still unable to increase the GTFP of the MI through energy structure. This study provides important insights for the government to fully leverage the positive role of social supervision in promoting the green development of heavy polluting industries such as MI.

Extraction of valuable critical metals from coal gangue by roasting activation-sulfuric acid leaching

ABSTRACT Coal gangue is a bulk industrial solid waste produced in the process of coal mining and washing, with the dual attributes of resourcefulness and hazardousness. It can be used as a reserve resource for valuable critical metals such as aluminum (Al), lithium (Li), gallium (Ga), and rare earth elements (REEs). In this paper, the occurrence modes of Li, Ga, and REEs in coal gangue were studied by sequential chemical extraction method. The extraction of valuable critical metals from the coal gangue was systematically studied by roasting activation-sulfuric acid leaching process, and the activation mechanism was elucidated. The results showed that roasting can destroy the inert kaolinite structure in coal gangue and significantly improve the leaching rate of valuable critical metals. Under the optimum conditions, the leaching rates of Al, Li, Ga, and REEs reached 86.51%, 74.46%, 95.45%, and 77.14%, respectively, and the leaching behaviors of Al, Li, and Ga were highly similar. In addition, the characterization of the leaching residue revealed 83.96% silicon oxide content with a loose and porous surface, which could be used to prepare silicon-based products. This study provides the theoretical basis and technical support for the utilization of valuable metals in coal gangue.

Research on preparation and related properties of macro-micro porous mullite ceramic skeletons via twice pore-forming technology.

A lot of solid waste coal gangue is produced every year in the process of coal mining and coal washing, which poses a great threat to human health. How to deal with coal gangue properly is still a serious problem. In this study the macro-micro composite porous mullite ceramic skeletons were successfully prepared using solid waste coal gangue and α-Al2O3 as main raw materials via twice pore-forming technology. The main phase composition of the porous ceramic skeletons was mullite tested by X-ray Diffractometer (XRD). The morphology and microstructure of the porous ceramic skeletons were analyzed by Scanning Electron Microscope (SEM). The results show that the microstructure of porous ceramic skeletons was mainly composed of mullite whiskers. With the increase of sintering temperature from 1200 °C to 1350 °C, the maximum length of mullite whiskers grew up from 2.68 μm to 8.10 μm and their average length grew up from 0.78 μm to 2.98 μm. The maximum compressive strength of the porous ceramic skeletons with 30 PPI and 45 PPI were 1.25 MPa and 1.54 MPa tested by Universal Testing Machine (UTM) at the sintering temperature of 1250 °C, respectively. The linear shrinkage, bulk density and pore stem density of the porous ceramic skeletons became larger with the rising of sintering temperatures from 1150 °C to 1350 °C. However, the corresponding performance values of 45 PPI porous ceramic skeletons were greater than that of 30 PPI at the same sintering temperature. The prepared porous ceramic skeletons will be used in ceramic-metal wear-resistant composites for the later research and the study provides a new idea for coal gangue on the comprehensive utilization with high added value and brings both good environmental and economic benefits.

Beneficiation Processing of Magnetite ore from Lampung as Dense Media for Dense Medium Separator in Coal Washing Plant

Until recently, coal washing plants in Indonesia are still using imported magnetite from Australia as dense media for dense medium separator units. To be effectively utilized as a dense media, magnetite ore needs to be concentrated to remove gangue minerals so that the final product will have more than 95% magnetic content, 95% weight passing 53 microns, and relative density ranging from 4.9 – 5.2 g/cm3. Experimental studies have been performed at the Department of Metallurgical Engineering ITB to concentrate fine magnetite ores from Lampung Province. Two process routes were chosen: grinding-magnetic separation and magnetic separation-grinding. Products from the two routes were sieve size analyzed, assayed and characterized. Magnetism characteristic was analyzed with VSM and relative density was measured with pycnometer. The first process route products have maximum magnetic content of 99.1% and particle weight passing 53 microns of 95.7%, while the second route have magnetic content of 95.2% and particle passing 53 microns of 97.1%. Concentrates from both routes have the same relative density of 4.5 g/cm3. Characterization by XRF and AAS gives Fe content of 46.6% and 48.8% for the first route product, and 52.1% and 52.9% for the second route. Lampung magnetite ore gives lower magnetism characteristic compare to Australian magnetite ore. Finer particle size gave lower magnetic saturation value, hence lower magnetism.

Ash Reduction of the Tailings of Agh-Darband Coal Washing Plant by Flotation Method

Ash Reduction of the Tailings of Agh-Darband Coal Washing Plant by Flotation Method

Fine and ultrafine flotation with the Concorde CellTM – A journey

The Concorde Cell is a high-intensity pneumatic flotation cell dedicated to fines and ultrafines. Its development by Professor Graeme Jameson and later on by Metso was driven by two considerations: a reduction in bubble size and an increase in the shear rate and energy dissipation rate increases the particle–bubble collision and attachment efficiencies of fine particles. The Concorde Cell is a technology which produces fine air bubbles with high carrying capacity, thereby allowing increased capacity per unit; smaller footprint and a greater recovery of valuable fine particles which can be lost in other flotation cells. In addition, with a smaller number of flotation stages or less recycle required to achieve the desired recoveries, operational expenditures like power, water and reagents can be reduced.In this article, the potential of the Concorde Cell is explored through six cases, from base metals to metallurgical coal. Its main operating parameters, Air-to-Pulp Ratio, froth washing, froth depth and tailings recycle ratio, are investigated and show that the metallurgical performance of the Concorde Cell follows expectations based on the literature. Amongst others, higher APR leads to higher mass pulls and higher recoveries but lower grades, deeper froth depth increases selectivity… But the data also demonstrate the typical complexity of flotation, whereby the negative impact of increased APR can be compensated with froth washing to maintain high grades at high recoveries for example.About ten industrial scale flotation projects worldwide are deploying the Concorde CellTM. The examples of a metallurgical coal washing plant in Australia and of a copper plant in Zambia prove the capacity of the Concorde Cell to better recover the fines and ultrafines while providing high selectivity. In the two case studies, the Concorde Cell outperformed the previous technology specifically on the finest fractions of the processed streams.

Analysis on morbidity characteristics of occupational diseases in Taian City from 2006 to 2021

Objective: To analyze the morbidity characteristics of new occupational diseases in Taian City from 2006 to 2021 and provide scientific evidence for local prevention and treatment of occupational diseases. Methods: In March 2022, the data of newly diagnosed occupational diseases in Taian City from 2006 to 2021 were obtained from Information Monitoring System for Occupational Diseases and Health Hazards. A descriptive analysis was performed for the distribution of onset age, working years, types of occupational diseases, region, industries, enterprise scale, enterprise economic type and the epidemic trend of occupational diseases. Results: 1362 cases of occupational diseases in 29 species of 9 categories were reported in Taian City from 2006 to 2021, including 1311 males and 51 females. The M (P(25), P(75)) of onset age and working age were 53 (47, 64) and 24.08 (16.56, 29.25) respectively. The top three categories of occupational diseases were occupational pneumoconiosis and other respiratory diseases (1128 cases, 82.82%), occupational otolaryngology and oral diseases (107 cases, 7.86%), and occupational chemical poisoning (70 cases, 5.14%) in sequence. Coal worker's pneumoconiosis, noise deafness, silicosis, poisoning of manganese and its compounds and cataract were the top five species of occupational diseases, which accounted for 69.60% (948/1362), 7.64% (104/1362), 5.58% (76/1362), 3.38% (46/1362) and 2.94% (40/1362) of the total cases of occupational diseases.There were significant differences among the composition of occupational diseases categories reported annually (P<0.001), but the number of occupational pneumoconiosis and other respiratory diseases was the highest on each year. The number of occupational diseases showed a decreasing trend with the year, and the optimal fitting curve was an growth curve. The number of newly diagnosed occupational diseases was predicted to be 172 cases from 2022 to 2026. Occupational pneumoconiosis and other respiratory diseases was the main disease in 6 counties. The occupational diseases cases were mainly distributed in Feicheng County and Xintai County, with 520 cases and 504 cases respectively, accounting for 75.18% of occupational diseases cases. The coal mining and washing industry had the largest number of occupational diseases cases, accounting for 73.05% of all occupational diseases cases. 91.85% of occupational diseases cases came from large and medium-sized enterprises. The economic type of enterprises with the most occupational diseases was state-owned enterprises, accounting for 74.52% of occupational diseases cases. Conclusion: The predominant occupational diseases in Taian City are occupational pneumoconiosis and other respiratory diseases, occupational otolaryngology and oral diseases, occupational chemical poisoning. And the prevention and control of occupational diseases should be strengthened in key industries such as coal mining and washing industry, key enterprises such as state-owned large and medium-sized enterprises.