Coal Processing Plant Research Articles

Research on factors affecting the spread of dust pollution in conveyor belt workshop and research on wet dust reduction technology.

At this stage, there are many dust-hazardous industries, and occupational pneumoconiosis has a high incidence for a long time. To solve the dust pollution problem in coal processing plant workshops, the dust particle field and liquid droplet particle field were numerically simulated using computational fluid dynamics (CFD), and the influences of the induced airflow and corridor wind speed on the internal airflow field of the workshop were investigated to derive the dust pollution mechanism in the coal plant workshop under the change in the wind flow field. In this study, it was shown that the wind flow rate in the coal processing plant workshop is mainly affected by the corridor wind speed, and the higher the corridor wind speed is, the higher the wind flow rate. The induced airflow mainly affected the direction of the wind flow field in the workshop. According to the conclusions obtained from the simulations, a spray dust reduction system was designed for the coal processing plant workshop and applied in the Huangyuchuan coal processing plant. On-site measurement revealed that the dust reduction effect inside the coal processing plant workshop is obvious, and the overall dust reduction efficiency in the workshop reaches more than 94%, which meets the requirements of environmentally sustainable development and clean production.

Stability Assessment of the Dam of a Tailings Pond Using Computer Modeling—Case Study: Coroiești, Romania

Anthropogenic activities related to mining generate both progress and a vast amount of waste that is responsible for environmental degradation. The Jiu Valley is one of the areas of Romania where mining has affected large areas of land, used to build mines and tailings ponds. The former Coroiesti coal processing plant (CCPP) is such a location with a total area of 25 ha containing approximately 5.5 million tons of tailings. The assessment of the stability of tailings dams is extremely important from safety and environmental aspects. This study proposes a solution based on numerical methods for determining the stability of a section of the dam of a tailings pond. The model of tailings pond no. 1, compartment B, from the Coroieşti Coal Preparation was built using COMSOL Multiphysics. Two scenarios of stability analysis were conducted on a section of the tailings dam: the FOS was determined using the shear strength reduction (SSR) method for both the initial and the current state of this TP. This method is a modern alternative to the limit equilibrium method, and its implementation by COMSOL is new to our country, thus aligning this methodology with current worldwide trends and developments in the field. The results obtained proved to be in line with those calculated in the past with traditional analytical methods, proving that the safety criteria of the studied TP/TD are being met.

Synergistic enhancement of coal slurry water sedimentation and dehydration process using PDMDAAC/PAM

Currently, most coal processing plants use a single pharmaceutical system with large dosage and poor sedimentation effect, resulting in poor subsequent dehydration effect. In this study, poly dimethyl diallyl ammonium chloride (PDMDAAC) as coagulant, and polyacrylamide (PAM) as flocculant, were used for synergistic enhancement of the coal slurry water sedimentation and dehydration process. The best pharmaceutical system was determined by integrating the evaluation indexes in the sedimentation and dehydration process. The mechanism of synergistic enhancement of coal slurry water sedimentation and dehydration process using PDMDAAC/PAM was revealed by analyzing zeta potential, SEM, XPS and FTIR spectroscopy results. Moreover, the Box–Behnken response surface methodology was used to determine the order of significance of coagulant dosage (Cc), flocculant dosage (Cm), and coal slurry water concentration (Cs) on the combined sedimentation and dehydration indexes, and Cm > Cs > Cc. Further, the correlation models between the combined sedimentation and dehydration indexes and each factor were established, the pharmaceutical system was further optimized, and model accuracy was verified. The optimal dosage of PDMDAAC10040 was 2.96 mg/L, and that of PAM2610 was 2.31 mg/L. Then, the industrial trials were conducted at the Tara Trench coal processing plant. Interestingly, after replacing the chemical regime, the efficiency of the thickener and filter press has been significantly improved, resulting in a 33.33% reduction in cost. This research can provide significant theoretical guidance and technical support for industrial applications.

Optimization study of intelligent decision-making system for coal processing plant based on big data analysis

Abstract Optimizing the intelligent decision-making system of coal processing plants is better to improve the economic efficiency of coal processing plants and realize the high-quality development of coal processing plants. In this paper, an integrated intelligent decision-making platform for a coal processing plant is constructed based on big data technology, and the intelligent data analysis techniques of the platform are optimized by using an improved whale optimization algorithm and BP neural network. Examples analyze the optimized crude coal slurry and flotation systems’ processes, and the economic benefits are analyzed. From the optimization of the crude coal slurry sorting system, the ash content in the 0.25mm particle size region was reduced from 55.37% to 13.12%, and the ash content in the −0.125mm particle size region was reduced from 42.68% to 15.96%. From the flotation system optimization, when the flotation time increases from 120s to 180s, the ash content increases from 16.27% to 17.19%, and then to 240s, the ash content increases to 19.44%. Using the integrated intelligent decision-making platform can achieve a net increase in revenue of 4,276,800 yuan for the crude coal slurry sorting system and a net increase of 11,274,200 yuan for the flotation system. This shows that the integrated intelligent decision-making platform can improve the coal processing plant’s quality and efficiency and promote intelligent production.

Analysis of Intelligent Control Strategy for Heavy Media Coal Separation Process Based on Deep Learning Model

Abstract Intelligent control of heavy dielectric coal beneficiation in coal plants is achieved with the help of deep learning models to optimize the control effect. In this paper, through the study of heavy dielectric coal separation methods and processes, a coal separation control optimization strategy based on a radial basis neural network optimized by the ant colony algorithm is proposed, and the RBF network is optimized by clustering using ant colony algorithm, which is used to determine the center and radius of the basic function of the RBF network. The suspension density, ash content of the fine coal and the level of the Hopper bucket, which affect the control effect, are selected as the inputs of the optimized model, and the control strategy is formulated according to the effect after adjusting the parameters. The experimental simulation results show that the ACO-RBF model has less oscillation when the ash value is changed, the final change is smoother, and the root mean square error of the ash value is 0.075%, which is 36.6% less than that of the PID algorithm. With the control strategy optimized by deep learning, the fluctuation range of the level of the qualified media barrel is controlled between 15 and 25 cm, and the volatility pattern of the level is more regular. The control system based on deep learning can better meet the requirements of the coal processing process and effectively improve the efficiency of a coal processing plant.

CFD simulation on internal flow field of typical hydrocyclone for coal and development of novel hydrocyclone

The work conducted flow field analysis of a typical hydrocyclone (φ500 type) in the Coal Processing Plant using CFD simulation, including hydrocyclone modeling, flow field development, static pressure distribution, three-dimensional velocity, and air column development. Besides, the effects of influential factors on the classification effect of hydrocyclone were studied. On this basis, a novel hydrocyclone model was developed and simulated for the ultrafine classification of coal slurry. The static pressure and velocity in the typical hydrocyclone have good symmetry and certain regularity. Decreasing the overflow pipe diameter and cone angle, while increasing the underflow pipe diameter, cylindrical section height, and feed rate will increase the classification efficiency of hydrocyclone. The novel hydrocyclone designed of annular feeding, small cone angle, and large cone bottom reduces energy consumption, decreases classification size, and improves classification accuracy. CFD simulation results show that the novel hydrocyclone has higher classification efficiency and smaller classification size over the typical hydrocyclone. The novel hydrocyclone develops an excellent ultrafine classification effect of coal slurry and provides a prospective approach for the industrial application of hydrocyclone in the fine coal ultrafine classification process.

A current affair: worker perceptions of noise exposure and occupational hearing loss in Australian coal mines.

The objective of the online survey was to determine worker attitudes towards, perceptions on hearing loss, and management of workplace noise; and to identify barriers within current strategies that prevent effective management of hearing health in Australian mines. This cross-sectional study utilized a modified survey design, initially designed for use by Safe Work Australia for a broader study published in 2010. The survey questionnaire was made available online to volunteer participants, recruited with the assistance of State and National Health and Safety, and mining organizations. Volunteer participants were required to be proficient in English, be employed by an Australian underground or open cut mine, including coal processing plants; or work as a contractor on one of the specified mine sites. All mining employees, regardless of occupation, job title, and occupational hearing loss classification or status, were invited to complete the questionnaire. Almost 60% of respondents indicated that they had high noise exposure for than 10 yr or more, and have some trouble hearing, mostly associated with infrequent tinnitus. Nearly 71% of these workers believe that the noise control strategies in their workplaces are effective, but this mostly refers to the use of hearing protection devices. The results indicate that general knowledge on the cause and effect of noise exposure in the workplace is well understood. However, due to the long latency associated with the development of noise-induced hearing loss (NIHL), there is an issue urgency in terms of risk management. It is surprising that most of the respondents recommended more inspections and administrative controls, especially since most respondents were health, safety, and environment (HSE) professionals. HSE professionals should be advocating for higher order, more permanent solutions, and not purely administrative controls and personal protective equipment. These findings raise the question of whether there is a multifaceted working-culture issue that needs to be addressed, in combination with higher order control implementation.

Shear strength of stockpiled coking coal – Existing data

Flowslides and stability issues have occurred periodically within stockpiles of coking (metallurgical) coal at coal processing plants and export terminals in Queensland’s Bowen Basin, and to a lesser degree in New South Wales, since the early 1970s. A description of the issue and summary of research at James Cook University (JCU) from 1973 to 2000 was published in ACARP Report C4057 (Eckersley, 2000). Eckersley (2022) partly updated that work with SEEP/W transient seepage modelling of a 12 m high coal stockpile constructed at Hay Point in late 1991 for which initial moisture content, pore water pressures at the stockpile base, outflows from subsoil drains and final density and moisture profiles were measured. This provided a good starting point for modelling of moisture movements within production coal stockpiles as required for meaningful slope stability analyses. The current paper provides an accessible summary of available data from laboratory shear strength testing of coking coal to assist in selection and critical assessment of parameters for slope stability analyses of coal stockpiles. This includes data for saturated coal likely to form the base of a stockpile and currently limited data for unsaturated coal forming the bulk of a stockpile. It then highlights some issues in the selection of parameters for stability analyses of coal stockpiles.

Большие данные как продукт обогатительной фабрики: реальность и перспективы на примере угля

The article examines the current and future flow of preparation's plant production processes and how they contribute to the generation of Big Data. It is shown that as the level of automation in the plant increases, the data produced becomes more extensive and varied. At the same time, it is possible to achieve a level when the generated information flows meet the criteria of the Big Data. As a basic example, a typical coal processing plant is used. The main sources, volumes, variety and speeds of data transfer to the processing plant are described and analyzed.

Spatially permeable screening distribution characteristics of banana-type vibrating screen material groups and industrial application

ABSTRACT Screening is a critical technology to achieve clean and effective use of coal. Due to their ability to achieve equal-thickness screening and excellent working efficiency characteristics, banana screens are widely utilized for material classification. The current work employs a vibration test and analysis system to investigate the laboratory-scale and industrial banana screens’ kinematic features. The screen surface’s amplitude gradients at the inlet and outlet ends of the laboratory and industrial scale banana screens were 0.5 mm and 7.5 mm, respectively, verifying the “strong-in, weak-out” transfer law of the vibration energy. The results of the 6 mm screening experiment in the laboratory indicated that the coal samples were concentrated in the middle of the screen surface with the highest screening efficiency of 95.05% and the lowest total mismatch content of 2.68%. A Birtley’s four-stage banana screen was utilized to classify the 6 mm raw coal during the on-site heavy media separation at the Tunbao coal processing plant. Besides, a better screening performance was obtained with an efficiency of 89.92% and total mismatch content of 5.31%. The differences in accuracy of the distribution rate curves were all less than 5%, indicating that the laboratory banana screen is a prominent guide for industrial applications.

Antropoloogiline vaade tööle: mõtisklusi kaevuritest ja diginomaadidest

This article gives an overview of how to research work and labour from an anthropological perspective. Based on the examples of my ethnographic research with miners, teachers and digital nomads, I show how the anthropology of work is based both on the dark anthropology of suffering and the dispossessed as well as the anthropology of the good. Anthropology of work, like anthropology in general, is characterised by a holistic approach, cultural relativism and the ethnographic method. I present five points that I have developed in my own research. First, based on the political economy approach, I argue that at the core of the anthropology of work are global inequalities and their everyday expressions at the workplace. I bring examples of my work in an underground mine in Estonia where miners try to regulate and control the tempo of everyday work while the managers try to make them work faster and more, and how such micro-tempo of the everyday is an expression of larger class structures. I also bring an example of the overlap of class and ethnicity among working-class Russian speakers in Estonia. I then discuss how anthropologists also consider the wider political-economic dimension as the industrial accidents in a Kazakhstani coal mine are affected by the global economic situation as well as global inequalities. Secondly, following David Graeber, I argue that work should be studied as producing both material value and immaterial values. I discuss how miners find salary and respect for their job both important and how Estonian teachers produce value in the future labour force and values as the moral base of society simultaneously and feel that they should be given both a decent salary and an immaterial value expressed in their autonomy and professionalism for their work. In neoliberal Estonia, where different values dominate and other professions are more appreciated, they claim to be lacking both. Thirdly, I argue that anthropological research looks at work from a wider perspective than just paid employment and considers also reproductive work. I bring an example of the transformation of women’s work in a Kazakhstani coal processing plant where the specialist work of regulating the production process has gradually been taken over by cleaning work akin to domestic reproductive tasks, invisible and unappreciated. Fourthly, I emphasise the embodied nature of work and how it creates intersubjective relations between bodies and inanimate objects such as machines or computer programmes. Finally, anthropology as a discipline that does not take the status quo for granted, is a good tool for questioning the centrality of work and dominance of the Protestant work ethic in the contemporary capitalist world. Based on the example of my work with digital nomads, I discuss how these young professionals knowingly decrease their work hours and are trying to spend their time on other pleasant non-commodified activities. Despite this, it is hard to completely denounce the dominant Protestant work ethic. I conclude by calling for both dark and utopian anthropology of work and more interdisciplinary collaborations.

The Study of Changing Anchor From Launching Model to Hanging Model on Barge Ship Owned by P.T. X

Anchor is a device for tethering a ship to the bottom of the water, in the sea, river, or lake, so that it does not move from place to place due to gusts of wind, current, or waves. Anchors are heavy equipment that is dropped to the seabed from a ship or boat to maintain its position so that it does not drift. PT X has several tug boats, small vessels whose function is to pull or push large ships in port. In addition, this ship also functions to pull barges filled with coal from the coal processing plant to be brought to the port, where the coal is unloaded to be carried by transport trucks. On these barges, damage to the anchor machine often occurs, especially the teeth on the gear-box, axle pulleys (pulleys), the main shaft of the main-gear (main gear), the gear-box casing, the teeth on the main-gear and others which have been sufficient so far. Interfere with operations, and the ship becomes idle. For this reason, this research was conducted to study the change in the anchor system from the glide model to a new system in the hanging model, in order to reduce the use of anchor winch power and avoid damage to the gear-box and anchor engine.

Identification of the Dynamic Properties of the Coal Flotation Process as a Control Object with the Use of the Kalman Filter

For various sorts of hard coal, enrichment by flotation is used for feed consisting of grains smaller than 0.5 mm. Regarding process automation, coal flotation is a multidimensional, dynamic nonlinear object of control, for which the main control signal is the flow rate of the flotation agent. Typically, in Polish coal-processing facilities the monitoring and control systems of the flotation process can only measure the parameter of the waste quality (content of ash in flotation tailings). This naturally becomes an output signal, enabling an indirect assessment of the ongoing process. Therefore, knowledge of the dynamic properties of the flotation process, analysed as an object with one control input (the flow rate of the flotation agent) and with one output for measuring (content of ash in flotation tailings) may be material in designing automatic control systems for this operation. It is important to use an appropriate identification method when developing a model of the dynamics of the flotation process, especially if the model parameters are to be determined on an ongoing basis. This article discusses the research method and presents the results of applying the method of identifying the dynamic properties of the coal flotation process with the use of the Kalman filter. We carried out a comparative analysis of the results obtained by this method based on the Kalman algorithm and the method of least squares, taken as the reference method. The presented parameters of the dynamic models were calculated based on actual data obtained from industrial tests conducted at the coal-processing plant at one of the Polish mines. It was demonstrated that, for control purposes, the Kalman algorithm can be successfully applied in identification of the coal flotation process. This is due to the fact that it gives satisfactory results in relation to the adopted reference method despite the fact that it is a recursive algorithm.

RUHR BÖLGESİ’NDE YER ALAN KÖMÜR İŞLETME TESİSLERİNİN DÖNÜŞÜMÜNDEKİ KISTASLARIN ZONGULDAK ÜZÜLMEZ TAŞKÖMÜRÜ İŞLETME MÜESSESİ İÇİN DEĞERLENDİRİLMESİ

Coal production, which has a large share among the world's energy resources, has also created an important industry branch in Turkey. The businesses in this area continued their existence within the borders of Turkey from the Ottoman Period to the Republican Period. The Ruhr Area, located in the state of North Rhine-Westphalia, Germany, which was the pioneer of industrialization movements in Europe in the 19th century, has become the center of coal production. The facilities involved in coal production not only have tangible cultural heritage elements belonging to original production processes and building materials, but also contain intangible elements of the cultural and social life of the society they belong to. With the destruction of coal production in the industrialized countries and the emergence of alternative clean energy sources, it was decided to close these enterprises over time. With this transition, coal mine processing plants located in the Ruhr Region and incorporating intangible and tangible periodical elements have been evaluated within the scope of adaptive reuse as a cultural heritage. In Turkey, on the other hand, coal production maintains its importance among energy sources. Since the economic benefit obtained from coal production is at the forefront, the change and destruction of the building groups in the production area is seen as normal. For this reason, it is important to record and document the coal mine processing plants, which are in danger of extinction. In this context, attention has been drawn to the potential potential of certain construction sites in Zonguldak belonging to the establishments and operating directorates of the Turkish Hard Coal Authority, which can be evaluated within the scope of adaptive reuse examples in the Ruhr Region. The aim of the study is to increase the awareness of these building groups in order to protect the coal-based industrial heritage and to develop criteria that will allow appropriate use transformation scenarios in line with the needs of the region.

Fully automated coal quality control using digital twin material tracking and statistical model predictive control for yield optimization during production of semi soft coking- and power station coal

The quality control of a two-stage coal washing process involves several complex components that need to be modelled accurately, to enable autonomous control of the process. The first objective is to develop a method to track the material through the washing process, while ensuring accurate washing prediction models are used. This was achieved through a digital twin model of the Grootegeluk 1 coal processing plant. The model is the amalgamation of manipulating and combining of data-sets from the plant historian, geological wash tables, and mining dispatch servers. This information is then used to control and set the processing medium densities of all 15 modules on the plant, 10 modules in the primary wash and 5 modules in the secondary wash. This controller has been successfully implemented and controlled the plant for 10 days.

Moisture Movement Analyses for Coal Stockpiles

Flowslides and stability issues have occurred periodically within stockpiles of coking (metallurgical) coal at coal processing plants and export terminals in Queensland’s Bowen Basin, and to a lesser degree in New South Wales, since the early 1970s. A description of the issue and summary of research at James Cook University from 1973 to 2000 was published in ACARP Report C4057. Despite this work, coal stockpile flowslides remain a significant risk at mine and port stockpiles due to their initiation without warning and dramatic consequences. To be able to adequately model the redistribution of moisture that leads to collapse of a stockpile and then conduct realistic stability analyses for design of preventative measures remains an elusive prospect. This paper therefore updates the previous work with results from SEEP/W transient seepage modelling within a 12m high 14,700 tonne coal stockpile constructed at Hay Point in late 1991 for which initial moisture content, pore pressures at the stockpile base, outflows from subsoil drains and final density and moisture profiles were measured. The model was based on results of laboratory permeability and column drainage tests on specimens taken from a composite bulk sample obtained at the time of stockpile construction. The coking coal product was from an operation with a known history of stockpile instability. Results were found to correspond well with pore pressures measured at the stockpile base and the stockpile’s final moisture profile provided account was taken of a thin higher permeability zone just above the subgrade. The approach adopted and parameters developed provide a significant advance in modelling of moisture movements within production coal stockpiles, with a view to subsequent slope stability analyses.

Process mineralogy approach to optimize curing-leaching in vanadium-bearing stone coal processing plants

The purpose of this study is to apply process mineralogy as a practical tool to further understand and analyze the reasons for low leaching rates in the curing-leaching process of vanadium-bearing stone coal and to find a solution or improvement to optimize the leaching index. Using vanadium-bearing stone coal with the V2O5 mass fraction of 0.88% as the research object, the effects of particle size, mineral composition, and sulfuric acid curing on the feed, intermediate, and final products of curing-leaching were analyzed. The main vanadium-bearing minerals in the feed samples included sericite/illite, montmorillonite, kaolinite, limonite, and schreyerite. Through the penetration depth analysis of sulfuric acid, the reason for the high vanadium content in the coarse leaching residue (0.205% V2O5) was found, mainly due to the poor curing effect and incomplete washing after screening. Therefore, thorough washing after sieving and further optimizing the curing process are necessary. The vanadium content of the fine leaching residue (0.078%) was low and the curing-leaching effect was good. However, the vanadium content in the thickened residue (0.296%) exceeded that in the fine leaching residue, which was attributed to the neutralization reaction in the #1 thickener. To solve this problem, the neutralization and thickening processes should be performed in separate equipment. The analysis and detection of key products is helpful for identifying problems and improving the curing-leaching circuit process.

Enhancement of dewatering performance of vitrinite-rich and inertinite-rich coals by surfactants: Experiment and simulation

The high moisture content of fine coals, especially flotation clean coals has affected the production of coal processing plants for a very long time. The two main components of fine coals are vitrinite and inertinite. The percentage of these two macerals present in the coal has an impact on the dewatering process. In this paper, the influence of surfactants on the dewatering effect of two samples with different maceral contents is studied. The results demonstrate that non-ionic surfactants have an excellent dewatering effect on vitrinite-rich coal, and it reduced the filter cake moisture by 1.84%, while cationic surfactants have an outstanding dewatering effect on inertinite-rich coal, and it reduced the filter cake moisture by3.81%. For both the coals, surfactant adsorption reduces the hydrophobicity of the coal. The best dewatering effect corresponds to the lowest filtrate surface tension and the loosest filter cake structure. Surfactants can reduce the pressure required to remove water from the filter cake by lowering the surface tension of the filtrate. In addition, surfactants have an agglomeration effect on fine coals, which increases the porosity of the coal and facilitates a low-moisture product. This study will help engineers select the suitable filter aid for the maceral content of coal and contribute to the development of efficient filter aids.

Numerical simulation study on optimization of ventilation airflow organization of a raw coal bunker

For the problem of gas accumulation in the product bunker of a company’s coal processing plant, three different ventilation schemes are proposed. The first one opens rectangular air inlet louvers on the wall of the product bunker and adds fans on the top for exhaust; the second one sets six ventilation windows evenly on the top of the product bunker for natural ventilation; the third one sends air to the interior of the bunker through small holes evenly distributed on the ventilation pipes and opens six exhaust ports on the wall. Finally, the effect of gas accumulation management of the ventilation scheme is simulated and analyzed through numerical simulation. The ventilation scheme is applicable to the gas accumulation management of raw coal bunkers with different coal storage heights, and provides a technical reference for the gas accumulation management of product bunkers in coal processing plants.

Лабораторні дослідження комбінованого методу зневоднення внутрішніми джерелами теплоти в умовах електричного нагріву

The constant deterioration of the quality of iron ore necessitates the processing of hard-to-enrich minerals that require deep enrichment, and complicates dehydration. Coal processing plants widely use processes carried out in aquatic environments, during which, along with the separation of mineral impurities in the coal remains a significant amount of ballast - water. Therefore, the final operations in the enrichment process are mechanical and thermal dehydration of coal enrichment products, primarily coal concentrates and sludges. The main difficulties are the drying of flotation concentrate (0…0,5 mm) and fine concentrate (0,5…6 mm), which retained after mechanical dehydration residual humidity of 23…27 % and about 13 %, respectively, which necessitates additional heat drying, the quality of coal concentrate, fuel consumption, energy and metal consumption of the process depend on the method and hardware design. The use of thermal drying for humidity adjustment is associated with a sharp increase in investment and consumption of scarce energy, which in today’s raw materials market and the situation in the economy are impractical. Dehydration by filtration on vacuum filters, which has become widespread in concentrators, does not allow obtaining enrichment products with conditioned humidity. At the raised humidity of concentrate expenses for its transportation to the consumer increase, and in the winter time it’s freezing in railway cars is possible. The development of effective methods for drying and heat treatment of dispersed materials is becoming important in practice due to the high requirements for the quality of finished products and the need to move to energy- and resource-saving technologies. Dehydration of sludge sediments is a big problem, because the existing filtration methods are not very suitable for this. Thus, the establishment of patterns of dehydration of finely dispersed materials is an urgent scientific task.