scholarly journals Technical Planning of Ventilation System to Support Development W Undercut in 2021 at PT. Freeport Indonesia Underground Mining

2020 ◽  
Vol 1 (1) ◽  
pp. 1-6
Author(s):  
Yudho Dwi Galih Cahyono
Keyword(s):  
Underground Mining ◽  
Ventilation System ◽  
Underground Mines ◽  
Design Criteria ◽  
Minimum Level ◽  
Block Caving ◽  
Heavy Equipment ◽  
Clean Air ◽  
Technical Planning ◽  
Main Components

Ventilation is an attempt to drain clean air into the mine and remove dirty air out of the mine. The main components of a mine ventilation system are intake, working, and exhaust. Intake is a tunnel and wells system where air flows from the surface into the mine. The purpose of the ventilation system in an underground mine is to provide and drain clean air into the mine for breathing and comfort of mine workers. Based on the Ventilation Design Criteria used by PTFI, the minimum airflow level required for every mine worker is 0.033 m3 / s / worker. Based on PTFI Ventilation Design Criteria, the minimum level in diluting smoke of heavy equipment diesel engine is 5 m3 / min or 0.08 m3 / s / kW. PT Freeport Indonesia is currently developing new underground mines namely Grasberg Block Caving (GBC) and Deep Mill Level Zone (DMLZ) which will be mined using the block caving method.

scholarly journals Sequencing of ore columns for planning of large underground mines

Mining Scince ◽  
2019 ◽  
Vol 26 ◽  
Author(s):  
Hylke Glass ◽  
Gert Van Hout
Keyword(s):  
Net Present Value ◽  
Underground Mining ◽  
Underground Mines ◽  
Systematic Design ◽  
Present Value ◽  
Block Caving ◽  
Initiation Point ◽  
Mining Technique ◽  
Mine Economics ◽  
Large Deposits

Block caving is an underground mining technique which extracts ore from the base, rather than from the top, of typically massive deposits. Mining infrastructure is developed below the deposit before extraction commences. A network of tunnels provides access to a collection of drawpoints from which ore is hauled. With large deposits, not all drawpoints are developed simultaneously and the opening of drawpoints is sequenced to facilitate orderly extraction of ore columns above drawpoints. Sequencing fixes the initiation point for the entire block cave, or a part of it, as well as identifying the direction of cave advancement. The drawpoint opening sequence exerts influence on the block cave mine economics. This paper discusses the optimisation of sequencing based on the net present value associated with extraction over the life-of-mine. It is shown that the maximum attainable net present value is obtained by a sequence in which ore columns are ranked in descending order of value. If significant variation of grade is present inside columns, an iterative procedure is given which corrects the sequence which yields the maximum net present value. The sequence with maximum net present value may not be practical or attractive from a caving perspective. Systematic design of sequences which permit orderly development of a block cave is discussed. To provide context, the net present value obtained from these feasible sequences is compared with the maximum attainable net present value. It is shown that the best feasible sequences are preferentially initiated in zones with columns of high-grade ore.

scholarly journals Optimization of the ventilation scheme for increasing production capacity of underground mines

2022 ◽  
pp. 89-93
Author(s):  
N.D. Iliinov ◽  
A.M. Mazhitov ◽  
A.B. Allaberdin ◽  
K.V. Vazhdaev
Keyword(s):  
Flow Rate ◽  
Underground Mining ◽  
Critical Path ◽  
Air Flow ◽  
Ventilation System ◽  
Production Capacity ◽  
Underground Mines ◽  
Air Flow Rate ◽  
Mining Operations ◽  
Mine Workings

Currently, many underground mines are revising their design solutions to increase their production capacity. This tendency is explained by the decreasing ore grades, as well as by the extensive introduction of mechanization in underground mining operations that has improved the output of mobile equipment by increasing the box capacity and engine power. Dieselpowered mobile vehicles are the most common in underground mining practice. The advantages of such engines are obvious as they generate more power than other types of engines. However, the high air demand for mine ventilation limits their application. This is associated with the need to increase the cross-sections of permanent mine workings in order to comply with the standard air flow rate with account of the increased ventilation capacity along with an increase in the inventory of mobile equipment in order to ensure the specified output of the mine. The specific features of mining operations are defined by the stage-wise character of commissioning various blocks of the deposit. Managing of production and development works provides an opportunity to ventilate the mine sections due to their consecutive commissioning, locally, with an isolated stream of air by means of mine workings that do not have the intersection of air streams. This provides a reduction of critical path of air travel up to 30% and reduction of the general mine ventilating pressure drop by at least 20% at constant air flow rate. The results of the work can be used in designing the ventilation system of underground mines both under construction and in operation.

scholarly journals Geological CO2 quantified by high-temporal resolution stable isotope monitoring in a salt mine

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Alexander H. Frank ◽  
Robert van Geldern ◽  
Anssi Myrttinen ◽  
Martin Zimmer ◽  
Johannes A. C. Barth ◽  
...  
Keyword(s):  
Temporal Resolution ◽  
Underground Mining ◽  
Stable Carbon Isotope ◽  
Underground Mines ◽  
Background Concentration ◽  
High Temporal Resolution ◽  
Salt Mine ◽  
Gas Migration ◽  
Mining Operations ◽  
Anthropogenic Contributions

AbstractThe relevance of CO2 emissions from geological sources to the atmospheric carbon budget is becoming increasingly recognized. Although geogenic gas migration along faults and in volcanic zones is generally well studied, short-term dynamics of diffusive geogenic CO2 emissions are mostly unknown. While geogenic CO2 is considered a challenging threat for underground mining operations, mines provide an extraordinary opportunity to observe geogenic degassing and dynamics close to its source. Stable carbon isotope monitoring of CO2 allows partitioning geogenic from anthropogenic contributions. High temporal-resolution enables the recognition of temporal and interdependent dynamics, easily missed by discrete sampling. Here, data is presented from an active underground salt mine in central Germany, collected on-site utilizing a field-deployed laser isotope spectrometer. Throughout the 34-day measurement period, total CO2 concentrations varied between 805 ppmV (5th percentile) and 1370 ppmV (95th percentile). With a 400-ppm atmospheric background concentration, an isotope mixing model allows the separation of geogenic (16–27%) from highly dynamic anthropogenic combustion-related contributions (21–54%). The geogenic fraction is inversely correlated to established CO2 concentrations that were driven by anthropogenic CO2 emissions within the mine. The described approach is applicable to other environments, including different types of underground mines, natural caves, and soils.

scholarly journals CFD-Based Determination of the Optimal Blowing and Suction Air Volume Ratio of Dual-Radial Swirl Shielding Ventilation in a Fully Mechanized Excavation Face

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Kuan Wu ◽  
Shiliang Shi ◽  
Yijie Shi ◽  
Yong Chen
Keyword(s):  
Ventilation System ◽  
Volume Ratio ◽  
Simulation Method ◽  
Dust Concentration ◽  
Dust Control ◽  
Underground Mines ◽  
Physical And Mental Health ◽  
Control Effect ◽  
Air Curtain ◽  
Air Volume

Dust is one of the main pollutants in coal mines, which seriously affects the physical and mental health of workers, as well as the safe production in underground mines. Dual-radial swirl shielding ventilation is a new ventilation method for a fully mechanized excavation face and can effectively reduce the dust concentration in the underground. The dust control effect of dual-radial swirl shielding ventilation is mainly affected by the thickness and integrity of the shielding air curtain, as well as the disturbance of the flow field near the air curtain. By changing the blowing and suction air volume ratio of the air duct, the strength of the radial air curtain can be improved, and the dust control effect of the dual-radial swirl shielding ventilation system can be effectively improved. In order to determine the optimal operating parameters of the dual-radial swirl shielding ventilation system, a numerical simulation method was used to conduct an in-depth study on the blowing and suction air volume ratio of the system. The results showed that when the blowing and suction air volume ratio of the air duct was 1.5, the radial air curtain had the highest strength. Under this condition, the dust concentration at the driver’s position of the roadheader was the lowest, and the dual-radial swirl shielding ventilation system can achieve an ideal dust control effect.

Wireless Sensor Network for Underground Mining Services Applications

2017 ◽  
pp. 504-530 ◽  
Author(s):  
Pankaj Kumar Mishra ◽  
Subhash Kumar
Keyword(s):  
Wireless Sensor Network ◽  
Sensor Network ◽  
Underground Mining ◽  
Underground Mines ◽  
Wireless Sensor ◽  
Maintenance Cost ◽  
Processing Unit ◽  
Central Processing ◽  
Underground Coal Mines ◽  
Logical Topology

Underground mines include a number of challenges due to their hostile milieu. Therefore, geotechnical and environmental monitoring mainly in underground coal mines have always been a critical task to ensure safe working conditions. If the monitoring device is cable based, then it requires an huge amount of cable deployment which can pose not only the high maintenance cost but difficulty in laying out the cable throughout the underground galleries. on the other hand, if it is direct wireless communication between sensing devices and the central processing unit, it is also not so feasible due to the crisscross, uneven and incline path. Therefore, Wireless Sensor Networks grab an opportunity to be deployed in such a hostile environment. Keeping in view, in the present chapter, attempts have been made to discuss the different aspects of wireless sensor network for underground coal mining services applications to overcome the various threats. Further, the best suited logical topology has been identified for the same.

A Self-Contained Architecture for Energy Recovery in Hydraulic Elevators

2014 ◽  
Author(s):  
Oscar Pena ◽  
Michael J. Leamy
Keyword(s):  
Analytical Model ◽  
Electric Motor ◽  
High Fidelity ◽  
The Novel ◽  
Heavy Equipment ◽  
Hydraulic Machines ◽  
Wide Range ◽  
Single Input ◽  
Main Components ◽  
Operation Cycle

This paper presents a novel energy storage and recovery architecture for speed-controlled hydraulic actuation in hydraulic elevators. The study is motivated by a need to increase efficiency in the fluid power industry, in general, and hydraulic elevators, in particular. In contrast to previously employed systems, the proposed architecture eliminates the need for throttling and inefficient energy conversions in electric motor/generators. The system has 6 main components: 1 actuator, 1 hydraulic transformer composed of 2 pump/motors, 2 accumulators, a reservoir or small auxiliary accumulator, and a small auxiliary electric motor to recharge accumulators. By operating in 3 different modes, the system is always able to recapture energy when decreasing actuation speed, and return energy if needed when increasing actuation speed. Assessment of the proposed architecture is accomplished through high-fidelity simulations and a simplified analytical model. The analytical model is derived with the pump/motor displacements as a single input. A heuristic rule-based control is developed to control the high-fidelity simulation through an operation cycle and a comparison to a counterweighted elevator simulation is done to validate energy advantages of the novel system. Preliminary results demonstrate the ability of the system to follow a velocity profile using a single input. Comparison with a conventional counterweighted hydraulic elevator shows a large increase in energy efficiency. It is believed the architecture may have additional applicability to a wide range of hydraulic machines, such as heavy equipment used in construction, manufacturing, forestry, etc.

Simulation of a novel intermittent ventilation system for underground mines

2014 ◽  
Vol 42 ◽  
pp. 206-215 ◽  
Author(s):  
Jundika C. Kurnia ◽  
Agus P. Sasmito ◽  
Arun S. Mujumdar
Keyword(s):  
Ventilation System ◽  
Underground Mines
Sign in / Sign up

Export Citation Format

Share Document