scholarly journals A Step-by-Step Procedure for Tests and Assessment of the Automatic Operation of a Powered Roof Support

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 697
Author(s):  
Dawid Szurgacz ◽  
Sergey Zhironkin ◽  
Michal Cehlár ◽  
Stefan Vöth ◽  
Sam Spearing ◽  
...  
Keyword(s):  
Automatic Control ◽  
Occupational Safety ◽  
Longwall Mining ◽  
Mining Operation ◽  
Primary Objective ◽  
Operating Conditions ◽  
Mining System ◽  
Step Procedure ◽  
Roof Rocks ◽  
Roof Support

A powered longwall mining system comprises three basic machines: a shearer, a scraper (longwall) conveyor, and a powered roof support. The powered roof support as a component of a longwall complex has two functions. It protects the working from roof rocks that fall to the area where the machines and people work and transports the machines and devices in the longwall as the mining operation proceeds further into the seam by means of hydraulic actuators that are adequately connected to the powered support. The actuators are controlled by a hydraulic or electro-hydraulic system. The tests and analyses presented in the developed procedure are oriented towards the possibility of introducing automatic control, without the participation of an operator. This is important for the exploitation of seams that are deposited at great depths. The primary objective was to develop a comprehensive methodology for testing and evaluating the possibility of using the system under operating conditions. The conclusions based on the analysis presented are a valuable source of information for the designers in terms of increasing the efficiency of the operation of the system and improving occupational safety. The authors have proposed a procedure for testing and evaluation to introduce an automatic control system into the operating conditions. The procedure combines four areas. Tests and analyses were carried out in order to determine the extent to which the system could be potentially used in the future. The presented solution includes certification and executive documentation.

scholarly journals INFLUENCE OF JET FAN INSTALLED ON A CUTTER-LOADER ON AIR DRAG IN VERY LONG LONGWALL PANELS

2021 ◽  
Vol 2 (4) ◽  
pp. 32-40
Author(s):  
Stanislav A. Pavlov
Keyword(s):  
Longwall Mining ◽  
Air Flow ◽  
Mining System ◽  
Air Drag ◽  
Longwall Panel ◽  
Jet Fan ◽  
Forced Air ◽  
Volume Method ◽  
Method Show ◽  
Roof Support

The article presents studies into aerodynamic processes in very long longwall panels. The computations in ANSYS using the finite volume method show that air drag in longwalls varies versus position of the longwall mining system in the panel. Enhancement of ventilation efficiency in longwalls requires reduction in air drag. The longwall air drag is governed by the air drags of the powered roof support and cutter-loader. The latter have very large dimensions which are technologically unchangeable. For this reason, it is necessary to ensure forced air flow to by-pass the cutter-loader in the longwall panel. The estimate of advantages of the proposed method for the air drag reduction in very long longwall panels is presented. The method consists in increasing air flow rate in the longwall with the help of an axial jet fan mounted on the cutter-loader.

ANALISIS KESTABILAN LERENG DINDING AKHIR DI PIT BARATLAUT PADA PENAMBANGAN BATUBARA DI PT. PUTERA BARA MITRA , KECAMATAN MENTEWE, KALIMANTAN SELATAN

KURVATEK ◽  
2018 ◽  
Vol 3 (1) ◽  
pp. 21-34
Author(s):  
Untung Wahyudi ◽  
Excelsior T P ◽  
Luthfi Wahyudi
Keyword(s):  
Slope Stability ◽  
Mining Operation ◽  
Subsurface Water ◽  
Mining System ◽  
Mine Site ◽  
Analysis And Design ◽  
The Stability ◽  
End Wall ◽  
Wall Slope ◽  
Mining Slope

PT. Putera Bara Mitra used open mining system for mining operation, Yet the completion of study on the end wall slope stability that  undertaken by geotechnical PT. Putera Bara Mitra in Northwest Pit and the occured a failure in the low wall on the 1st June 2012 led to the need for analysis and design the overall slope at the mine site. To analyze and design the overall slope, used value of the recommended minimum safety. The value was based on company for single slope SF ≥ 1.2 and SF ≥ 1.3 for overall slope. The calculation used Bichop method with the help of software slide v 5.0. Geometry improvements was done at the low slopes that originally single wall with a 30 m bench height and a slope 70° with SF = 0.781, into 4 levels with SF = 1.305. The analysis explained the factors that affect the stability of the low wall included the mining slope geometry, unfavorable drainase system, material stockpiles and seismicity factors. It was necessary to do prevention efforts to maintain the stability of the slope included the redesign to slope geometry, handling surface and subsurface water in a way to control slopes draining groundwater, vegetation stabilization using and monitoring slope using Total Station with Prism and Crackmeter to determine the movement of cracks visible on the surface. 

scholarly journals Alginate/porous silica matrices for the encapsulation of living organisms: tunable properties for biosensors, modular bioreactors, and bioremediation devices

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
Mercedes Perullini ◽  
Mariano Calcabrini ◽  
Matías Jobbágy ◽  
Sara A. Bilmes
Keyword(s):  
Physical Stability ◽  
Porous Silica ◽  
Biological Response ◽  
Optical Quality ◽  
Operating Conditions ◽  
Radius Of Gyration ◽  
Host Matrix ◽  
Operation Conditions ◽  
Step Procedure ◽  
Living Organisms

Abstract:The encapsulation of living cells within inorganic silica hydrogels is a promising strategy for the design of biosensors, modular bioreactors, and bioremediation devices, among other interesting applications, attracting scientific and technological interest. These hostguest multifunctional materials (HGFM) combine synergistically specific biologic functions of their guest with those of the host matrix enhancing their performance. Although inorganic immobilization hosts present several advantages over their (bio)polymer-based counterparts in terms of chemical and physical stability, the direct contact of cells with silica precursors during synthesis and the constraints imposed by the inorganic host during operating conditions have proved to influence their biological response. Recently, we proposed an alternative two-step procedure including a pre-encapsulation in biocompatible polymers such as alginates in order to confer protection to the biological guest during the inorganic and more cytotoxic synthesis. By means of this procedure, whole cultures of microorganisms remain confined in small liquid volumes generated inside the inorganic host, providing near conventional liquid culture conditions.Moreover, the fact of protecting the biological guest during the synthesis of the host, allows extending the synthesis parameters beyond biocompatible conditions, tuning the microstructure of the matrix. In turn, the microstructure (porosity at the nanoscale, radius of gyration of particles composing the structure, and fractal dimension of particle clusters) is determinant of macroscopic parameters, such as optical quality and transport properties that govern the encapsulation material’s performance. Here, we review the most interesting applications of the two-step procedure, making special emphasis on the optimization of optical, transport and mechanical properties of the host as well as in the interaction with the guest during operation conditions.

Cross-sectional evaluation of surface contamination with 9 antineoplastic drugs in 93 Canadian healthcare centers: 2019 results

2020 ◽  
Vol 26 (8) ◽  
pp. 1921-1930
Author(s):  
Marie Palamini ◽  
Sébastien Gagné ◽  
Nicolas Caron ◽  
Jean-François Bussières
Keyword(s):  
Occupational Safety ◽  
Ultra Performance Liquid Chromatography ◽  
Primary Objective ◽  
Outpatient Clinics ◽  
Antineoplastic Drugs ◽  
Cross Sectional ◽  
Health Group ◽  
Liquid Chromatography Tandem Mass ◽  
Kolmogorov Smirnov ◽  
The Impact

Introduction The primary objective was to describe environmental contamination with National Institute for Occupational Safety and Health Group 1 hazardous drugs in oncology pharmacies and outpatient clinics in Canada in 2019, as part of an annual surveillance project. Methods In each participating center, 12 standardized sites (6 in the oncology pharmacy and 6 in outpatient clinic) were sampled. Each sample was prepared to allow quantification of six antineoplastic drugs (cyclophosphamide, ifosfamide, methotrexate, gemcitabine, 5-fluorouracil, and irinotecan) by ultra-performance liquid chromatography-tandem mass spectrometry. Samples were also tested for three additional antineoplastic drugs (docetaxel, paclitaxel, and vinorelbine) without quantification. The impact of certain characteristics of the sampling sites was evaluated with a Kolmogorov–Smirnov test for independent samples. Results Ninety-three Canadian centers participated in 2019, with a total of 1045 surfaces sampled. Cyclophosphamide was the drug most often found in the surface samples (32.4% of samples with positive result), followed by gemcitabine (20.3%). The front grille inside the biological safety cabinet (81.5% of samples positive for at least one antineoplastic drug) and the armrest of a treatment chair (75.8%) were the most frequently contaminated surfaces. Centers with more oncology inpatient and outpatient beds, those that prepared more antineoplastic drugs each year, and those that used more cyclophosphamide each year had higher concentrations of cyclophosphamide contamination on the surfaces tested ( p <  0.0001). Conclusion Traces of dangerous drugs were found in oncology pharmacies and oncology outpatient clinics in 93 Canadian hospitals in 2019. However, the quantities measured were very small. Every healthcare worker should consider these work areas to be contaminated and should wear appropriate protective equipment.

scholarly journals Prioritizing Safety Training for a More Personal Compliance of a Safe and Healthy Work Environment among Students and Staff of Higher Education Institutions of Selangor

2018 ◽  
Vol 7 (3.30) ◽  
pp. 388
Author(s):  
Mokana Muthu Kumarasamy ◽  
Mazni Saad ◽  
Reeny Karlina Abdul Rauf ◽  
Noor Malinda Mohamed Mohan ◽  
Mohd Hanafi Azman Ong
Keyword(s):  
Work Environment ◽  
Occupational Safety ◽  
Safety Training ◽  
Primary Objective ◽  
Occupational Safety And Health ◽  
Educational Institutions ◽  
Safety And Health ◽  
Safe Work ◽  
Healthy Work ◽  
Positive Effect

Safety is an important element in an organization. A safe work space makes safety a priority throughout the organization. Improved safety will minimize job accidents, injuries, medical illnesses and death. Occupational safety and health (OSH) training that is provided by the top management of universities will create a safe and comfortable environment for both the staff and students. It also guarantees that every employee is safe in the workplace. Thus, the primary objective of this study is to investigate the effect of safety training towards personal compliance. A total of 234 questionnaires were distributed to 20 higher educational institutions in Selangor, Malaysia. A conclusion was reached once the data were analyzed using SPSS; that safety training (B = 0.364, t = 11.90, p <.01) significantly has a positive effect on Personal Compliance.  

An Integral Design Approach for Deep Sea Mining Systems Using Dredging Technology

2010 ◽  
Author(s):  
P. M. Vercruijsse ◽  
R. Lotman
Keyword(s):  
Transport System ◽  
Deep Sea ◽  
Mining Operation ◽  
Integral Solution ◽  
Mechanical Interaction ◽  
Pumping Power ◽  
Mining System ◽  
Mining Tool ◽  
Transport Flow ◽  
Slurry Transport

Experience in the area of wet mining and the dredging industry learns that the excavation system cannot be seen separate from the slurry transportation system. These two key systems in a deep sea mining operation interrelate to such extend that they must be developed towards an integral solution. The nominal production, peak production and variability of these figures must match for all sub-systems in the overall mining system to optimize for mining efficiency; we call this the ‘game of capacities’. Also the configuration of the excavation and transport system has great consequences. For instance an important question is whether to place the first pump and its drive of the slurry transport system on the seafloor mining tool or in the riser system. The choices made impact amongst others on; the mining tool’s reach (and thus efficiency), the seafloor mining tool’s propulsion system and its geo-mechanical interaction, the slurry transport flow and pumping power requirements. This paper will discuss the several dependencies of the (producing) subsystems and important choices for configuration and their consequences regarding technology, capex, opex, reliability and maintainability.

Automatic control of operating conditions in the annealing lehr of a thermally polished glass line

1997 ◽  
Vol 54 (7-8) ◽  
pp. 199-201
Author(s):  
V. I. Kondrashov ◽  
Yu. N. Pentkov ◽  
L. G. Kopchekchi ◽  
F. B. Novikov
Keyword(s):  
Automatic Control ◽  
Polished Glass ◽  
Operating Conditions

In situ gasification of coal, a natural example: history, petrology, and mechanics of combustion

1982 ◽  
Vol 19 (3) ◽  
pp. 514-523 ◽  
Author(s):  
R. M. Bustin ◽  
W. H. Mathews
Keyword(s):  
Roof Rock ◽  
Vitrinite Reflectance ◽  
Ground Surface ◽  
Coal Ash ◽  
Sharp Decrease ◽  
Upper Jurassic ◽  
Thick Coal Seam ◽  
Roof Rocks ◽  
Roof Support

A 6 m thick coal seam of the Upper Jurassic and Lower Cretaceous Mist Mountain Formation in the southeastern Canadian Cordillera has been burning since 1936. The upper 3 m of coal is being consumed to an estimated depth of 20 m. Temperatures in excess of 1100 °C are locally reached, resulting in the melting of overlying sandstones and shales. The melted and vitrified rocks contain a new suite of minerals, including diopside, anorthite, cristobalite, and tridymite. Underlying the burnt coal ash is a zone of coke averaging about 10 cm thick, which is in turn underlain by unaltered coal.Within the area of combustion three zones can be distinguished: an advance zone, where open cracks are developed at the ground surface; a zone of active combustion, where volatiles driven off the coal burn en route to the surface and at the mouth of vents; and an abandoned zone marked by vents, some of which act as air intakes. Approximately 1000 t/year of coal is consumed, giving an energy release of about 1 MW. The heat generated is carried both forward and upward by convecting gas, thereby coking the coal and baking the roof rock. Little heat is carried downward, as evident from a sharp decrease in vitrinite reflectance below the zone of combustion.The baked roof rocks are brittle and extensively fractured, providing little roof support. The completely fused and scoriaceous rock and welded associated breccias, on the other hand, have greater coherence. This welding hinders roof collapse and thereby assists the passage of gases.

Design Recommendations for Controlling the Jam-Clearing Hazard on Recycling Industry Balers

2005 ◽  
Author(s):  
T. Mick ◽  
K. Means ◽  
J. Etherton ◽  
J. Powers ◽  
E. A. McKenzie
Keyword(s):  
United States ◽  
Laboratory Testing ◽  
Occupational Safety ◽  
The United States ◽  
Operating Conditions ◽  
Occupational Safety And Health ◽  
Hydraulic Pressure ◽  
Design Recommendations ◽  
Recycling Industry ◽  
Safety And Health

Between 1986 and 2002, there were 43 fatalities in the United States to operators of recycling industry balers. Of these fatalities, 29 involved horizontal balers that were baling paper and cardboard (Taylor, 2002). Balers often become jammed while the baling process is occurring, and the only way to remove the jam is manually. This requires an employee to place a limb of their body into the jamming area and remove the material that is causing the jam. While lockout and tagout procedures reduce the risk of hazardous energy being released, they can still be easily bypassed, ignored, or forgotten. Recent efforts to reduce machine-related injury and death involve the development of a control system for these machines that automatically detects hazardous operating conditions and responds accordingly. The system is being developed at the National Institute for Occupational Safety and Health (NIOSH). This system, JamAlert, automatically terminates the power to the machine when a jam is detected. JamAlert detects a jam by observing both the strain that is experienced by the shear bar of the baler and the hydraulic pressure at which the ram is operating. The strain that is experienced by the baler shear bar when a jam is initiated was calculated in this study through laboratory testing and finite element modeling. Design recommendations are presented on how best to tune the JamAlert’s operating program to most effectively control the jam-clearing hazard.

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