Ore Bin Research Articles

Investigating the efficacy of foam-based dust particle capture for dust elimination in ore pass unloading: A similar experimental study

Dust pollution arising from ore unloading poses significant concerns for occupational health. The foam-based dust particle capture presents a promising solution for dust suppression due to enhanced wettability, broader dust capture area, and stronger adhesion. This study designed a similar experiment platform to investigate how unloading conditions and foam parameters influence airflow dynamics and dust migration. The results indicate that airflow intensity and dust source are pivotal factors affecting dust concentration. Additionally, applying foam at the unloading port on the first level or the ore bin proves effective. Foam-dust interaction duration and airflow intensity are crucial determinants of dust suppression efficacy. Furthermore, the study reveals that the foam has a dual effect on dust control: while it efficiently captures dust particles to mitigate pollution, it can also disrupt airflow unfavorably. This research offers valuable insights into optimizing the spatial arrangement and quantitative application parameters of foam equipment.

Analysis of respirable dust exposure data collected at a Zambian copper mine between 2017 and 2022.

Mine workers are occupationally exposed to respirable dust, which can cause irreversible lung diseases and controlling exposure concentrations to as low as reasonably practicable is, therefore, essential. To implement exposure reduction strategies and adequately manage exposure to hazardous chemicals, exposure needs to be measured and recorded according to a standard exposure management plan. This study aimed to assess the available respirable dust exposure data measured between 2017 and 2022 in various work areas and job categories at two mining shafts and a concentrator plant of a Zambian copper mine. Additionally, the monitoring program implemented at the mine was assessed for appropriateness. Descriptive data analysis was used to create an exposure matrix comprising 253 exposure measurements. Approximately 5.6% of the measured concentrations exceeded the South African time-weighted average occupational exposure limit (TWA-OEL) of 3 mg/m3. The geometric means of respirable dust exposure for shaft A, shaft B and the concentrator plant were 0.44 mg/m3, 0.44 mg/m3, and 0.68 mg/m3, respectively. The work areas with the highest maximum exposure results were the tipping area (18.0 mg/m3) at shaft A, the sump and waste bin (8.05 mg/m3) at shaft B and the screening (10.8 mg/m3), secondary crusher (14.0 mg/m3), foreign ore bin (4.43 mg/m3), and tertiary crusher (5.07 mg/m3) areas at the concentrator plant. It was found that the monitoring strategy implemented at the mine was flawed and did not collect a sufficient number of samples in each area during each year to make rigorous statistical assessment possible. This study highlights the sampling strategy's shortcomings and recommends adopting a standardized monitoring strategy, such as EN689, to improve the respirable dust monitoring program at the mine. Additionally, this strategy can be implemented across Zambia and, if implemented correctly, it has the potential to be improve exposure monitoring across the country as no standard sampling strategy is currently enforced by the Government.

Study on vibration characteristics of ship mining system under composite load

The load that borne by ship mining system is very complex. The vibration of lifting pipe can be significantly affected by ocean current and wind load, which has a key impact on material lifting, ore bin storage and ship towing. Considering the composite load condition, the vibration control equation of mining ship is established based on the transverse swing mechanism of ship hull, and the variation law of transverse disturbance is obtained. The dynamic equation is constructed according to the bearing characteristics of the lifting system and the D’Alembert principle. The Wilson method is used to analyze and obtain the transverse vibration spectrum response of the lifting pipe under different wind loads, hull disturbance velocity and water depth. Based on the analogy method and hammering method, the vibration feedback test-bed of the lifting system is built, and the time-domain and frequency-domain vibration characteristics of the lifting pipe model under different water depths are obtained. The results show that in shallow water, the disturbance of mining ship and the composite load of ocean current are the key factors affecting the vibration amplitude of lifting pipe respectively. With the increase of water depth, the characteristic frequency and amplitude of the system decrease, and the amplitude gradually presents a discontinuous phenomenon.

Experimental research and analysis on the resistance characteristics of simulated ore bin in water

In order to research the variation law of the longitudinal resistance coefficient of the ore bin in the marine mining system under different length–diameter ratio, external shape, additional weight and Reynolds number, a set of experimental system for testing the resistance coefficient was designed and built independently. By analyzing the experimental results, it can be seen that under the same conditions, the resistance coefficient decreases gradually with the increase of Reynolds number and finally fluctuates around a certain value. Increasing the excitation displacement will reduce the overall resistance coefficient of the ore bin. The smaller the length-diameter ratio is, the larger the corresponding force value when the vibration acceleration of the ore bin is 0, and the larger the overall resistance coefficient is. The resistance coefficient of the cylindrical section is greater than that of the rectangular shape. In order to reduce the longitudinal vibration and the transverse towing offset, the shape of the ore bin should be cylindrical in actual design and production. At low Reynolds number, the increase of added weight will increase the resistance coefficient, while at high Reynolds number, the change of added weight will not cause the change of resistance coefficient.

Study on the control of high ore pass dust pollution by pre-injection foam dedusting technology in the ore bin.

The impact airflow generated by ore unloading in the chute raises the dust carried by the ore itself and the floating dust, and then, the dust raised enters the roadway with the airflow and pollutes the environment. In order to minimize the amount of dust entering the roadway and reduce the pollution of unloading dust, we conducted an experimental study of selection of best foam formula and pre-injection foam dust dedusting technology in ore bin. It was found that the optimal foaming formula was 1.0% sodium dodecyl benzene sulfonate (SDBS) + 0.5% sodium dodecyl sulfate (SDS) + (0.2 ~ 0.4%) sodium carboxymethyl cellulose CMC-Na and coconut oil monoethanolamide (CMEA) by the compound experiment using two evaluation criteria of initial foaming amount and foam defoaming rate. When the air pressure is 0.7MPa, the foaming rate of the foam generator is proportional to the gas and liquid flow rate and the best foaming gas and liquid flow ratio is 27.8. Under this circumstance, the foaming rate of the foaming formula is 500l/min. When the height of foam is controlled at 15cm, the effect of foam dust removal is the best. The dust emission rate from the foam to the fourth level can reach 60%, and the dust fall rate of the third level is 28%, which effectively reduces the dust production and relieves the pressure of the spray hole dust fall at the wellhead.

Analysis of the Deep Sea Mining Pipe Transverse Vibration Characteristics Based on Finite Element Method

This paper analyzes the transverse vibration laws of 5000 m ladder-shaped mining pipe under different towing velocities and accelerations in the ocean, thinking of the pipe as the beam model, discretized based on the FEM. The algorithm is used to solve the problem to obtain the transverse vibration law. The research shows that the mining pipe overall transverse vibration trend decreases first and then increases, the minimum vibration value occurs at 3000 m, and the maximum occurs at the top. Increasing the towing velocity, acceleration, and ore bin weight will increase the transverse vibration value. The vibration intensity produced by the same acceleration in the constant acceleration and deceleration stages is different, and the damping effect after adding the same damping is also different. In the range of 0.01 m/s2–0.1 m/s2, the vibration reduction effect after adding damping in the constant deceleration stage is more significant, and in the range of 0.1 m/s2-0.2 m/s2, the vibration reduction effect after adding damping in the constant acceleration stage is more significant. In the stage of the constant acceleration or deceleration, when adding the same damping, the vibration intensity generated by the large acceleration is still far greater than the vibration intensity generated by the small acceleration, so the mining ship should keep the small acceleration for towing motion.

Comparative Analysis of Longitudinal and Transverse Vibration Characteristics of Ocean Mining Pipe

In this paper, the 5000 m mining pipe is taken as the research object, and the transverse and longitudinal vibration laws of the pipe under different working conditions are analyzed. Based on the finite element method (FEM), the pipe is discretized and calculated by the Wilson-θ Wilson - θ integral method; finally, the corresponding vibration laws of the mining pipe are obtained. The research shows that the mining pipe vibration responses are irregular motion, with the obvious oscillation phenomenon, and the overall vibration trend decreases first and then increases from the top to the bottom; the maximum vibration response occurs at the pipe top. Under the same working conditions, increasing the towing velocity will decrease the overall longitudinal vibration amplitude and increase the overall transverse vibration amplitude. While the ore bin weight will increase the longitudinal vibration amplitude and decrease the transverse vibration amplitude, increasing the mining pipe large diameter stepped section length and damping will decrease the longitudinal and transverse vibration simultaneously. When the towing velocity is between 0–2.8 m/s, the longitudinal vibration intensity is large, which is the main vibration mode. When the towing velocity is 2.8 m/s, the critical point is reached, and the longitudinal and transverse vibrations have the same intensity. When the towing velocity is greater than 2.8 m/s, the transverse vibration intensity is gradually greater than the longitudinal vibration intensity; at this time, the control of the transverse vibration should be appropriately increased.

Investigation of Grain Size Distribution of Conveyed Copper Ore for Modelling Ore Flow through a Bunker

Knowledge of the particle size distribution of mined ore enables improvement of the main processes of the whole mining value chain: blasting, ore loading and haulage and ore processing. Photogrammetry with image analysis techniques was proposed for the on-line identification of grain size distribution of conveyed ore. Preliminary laboratory tests were performed on the experimental belt conveyor to evaluate the quality of photographs for various camera settings. Grain size distribution of transported copper ore was determined on the basis of photographs taken over the main haulage conveyor that feeds mined material to the underground ore bin located at skip-filling station of the winding shaft. Size distribution slope was calculated using the Split Desktop 4.0 software package to estimate the degree of rock fragmentation. Fine fractions (<10 mm) accounted for more than 40% of transported bulk material. Such a large portion of fine fraction may be attributed to the lithology of conveyed material. Individual rock lumps 600 mm or larger constituted a minor part of the total amount of mined ore. The actual ore granulation influences ore flow through the bin, which was simulated using a discrete element method model to obtain information about the ore stream leaving the winding shaft.

Analysis and Research on Longitudinal Vibration Characteristics of Deep Sea Mining Pipe Based on Finite Element Method

This paper aimed to study the longitudinal vibration characteristics of the 5000 m mining pipe in the ocean under different working wind conditions, offset angle, damping, and ore bin weight. Based on the finite element method, the mining pipe is simplified into beam element and discretized, and the physical and mathematical models of the mining pipe system are established. The Wilson-θ direct integral method is adopted for numerical calculation. The results show that the longitudinal vibration of the mining pipe is irregular, which presents the phenomenon of oscillation. The vibration amplitude decreases first and then increases from top to bottom, the minimum vibration amplitude appears at 1000 m, and the maximum vibration amplitude appears at the top of the mining pipe. Under the same working wind condition, the overall longitudinal vibration amplitude of the mining pipe can be increased by increasing the ore bin weight and the offset angle, but neither of them can change the frequency of the longitudinal vibration. The closer the excitation frequency generated by different working wind conditions is to the natural frequency, the larger the mining pipe longitudinal vibration amplitude is. The closer the vibration frequency generated by the same excitation frequency is to the natural frequency, the stronger the vibration intensity is, and when damping is added, the vibration intensity decreases faster.

Risk Assessment of Potentially Toxic Elements Pollution from Mineral Processing Steps at Xikuangshan Antimony Plant, Hunan, China

We evaluated the direct release to the environment of a number of potentially toxic elements (PTEs) from various processing nodes at Xikuangshan Antimony Mine in Hunan Province, China. Sampling wastewater, processing dust, and solid waste and characterizing PTE content (major elements Sb, As, Zn, and associated Hg, Pb, and Cd) from processing activities, we extrapolated findings to assess wider environmental significance using the pollution index and the potential ecological risk index. The Sb, As, and Zn in wastewater from the antimony benefication industry and a wider group of PTEs in the fine ore bin were significantly higher than their reference values. The content of Sb, As, and Zn in tailings were relatively high, with the average value being 2674, 1040, and 590 mg·kg−1, respectively. The content of PTEs in the surface soils surrounding the tailings was similar to that in tailings, and much higher than the background values. The results of the pollution index evaluation of the degree of pollution by PTEs showed that while dominated by Sb, some variation in order of significance was seen namely for: (1) The ore processing wastewater Sb &gt; Pb &gt; As &gt; Zn &gt; Hg &gt; Cd, (2) in dust Sb &gt; As &gt; Cd &gt; Pb &gt; Hg &gt; Zn, and (3) surface soil (near tailings) Sb &gt; Hg &gt; Cd &gt; As &gt; Zn &gt; Pb. From the assessment of the potential ecological risk index, the levels were most significant at the three dust generation nodes and in the soil surrounding the tailings reservoir.

Calculation Method of Ore Heap Volume Model Based on Open Pit Ore

As an important part of the ore transportation route, the open-pit ore bin can store ore when there is more incoming material in the upper stream and act as a buffer. When the material is missing, it can be fed to prevent the downstream machine from idling. We can calculate the location of a certain grade of ore through the volume of the mine heap to prepare for the later addition of ore. The volume of the ore bunker is roughly estimated by human observation, which results in a large volume error and affects the later addition of ore. In order to avoid the deviation of the volume calculation caused by rough estimation, a volume model calculation method based on ore heap is proposed. Through the research on the mechanism of ore heap formation mechanism, the principle of integration in higher mathematics is used to reasonably divide the ore heap. Therefore, an accurate formula for calculating the volume of the ore heap is obtained, which provides accurate guidance for the later addition of ore.

Top Charging Car Automatic Control System Based on PLC

In view of the furnace top charging car ore bin automatic distributing problems, This article puts forward a kind of high reliability, stable performance of automatic material distributing control system ,The system uses wireless communication technology、Ore bin material level detection technology and High reliability of PLC control technology, Achieving material distributing car accords to the need of ore bin for charging, Making material distributing more rational and effective, reduce labor intensity and improve the level of automation for production.`

Update on the Mineralogy of the San Rafael Mine Nye County, Nevada

Unless otherwise noted, all mineral photos by Tom Loomis of specimens from his collection Figure 1. View to the southwest of abandoned San Rafael mine headframe and ore bin at sunset, summer 2008. ...

Rehabilitation of an underground ore storage bin at Myra Falls : K. Reipas, CIM Bulletin, 88(994), 1995, pp 51–55

Westmin Resources Ltd. operates the 3300 TPD H-W underground copper/zinc mine on Vancouver Island. Ore storage underground is handled in a 6000 tonne coarse ore bin and a 3000 tonne fine ore bin. Both of these bins have experienced significant wear since excavation and construction in 1985. Wear problems have included both deteriorating rock walls as well as worn out steel liners and concrete at the discharge points from the bins. Extensive rehabilitation work was completed in 1993. The basis of this paper is the rehabilitation work done on the coarse ore bin. The design and installation of ground control measures are discussed. The bin access methods used to allow the work to proceed quickly and safely are also presented. This involved the use of Tekfoam safety bulkhead to protect workers.

Construction and geological engineering of an underground ore bin : Bratton, G P; Agapito, J F T Proc of the 1985 Rapid Excavation and Tunneling Conference, New York, 16–20 June 1985 V1, P177–191. Publ New York: AIME, 1985

Construction and geological engineering of an underground ore bin : Bratton, G P; Agapito, J F T Proc of the 1985 Rapid Excavation and Tunneling Conference, New York, 16–20 June 1985 V1, P177–191. Publ New York: AIME, 1985

Computer Control of Lead/Zinc Concentrator Crushing Plant Operations of Mount ISA Mines Limited

Mount Isa Mines Limited uses process control computers in its major process areas - namely the Lead/Zinc Concentrator, Copper Concentrator, Lead Smelter and Copper Smelter - to implement more complex control schemes. In this paper the development and implementation of the computer control system at the crushing plant of the Lead/Zinc Concentrator is discussed.There are some significant control problems associated with this plant which include variable plant operating conditions and long time delays. The approach that has been taken to overcome these problems was to develop a robust and comprehensive system which controls most of the major equipment Items, including the crude ore bin feeding system, the primary and secondary crushing, their associated storage and feeding systems.The control scheme is centred on dynamically compensated controllers of ore throughput and crusher power draft. To achieve maximum robustness, directed logic schemes which monitor the status of the different sections of the plant and make decisions on how to control the rest of the plant were incorporated into the control system. The control system has been able to handle the most common plant upset conditions as well as provide improved performance under steady running conditions.

坑内主要坑井の貯鉱能力に関する研究

坑内主要坑井の貯鉱能力に関する研究