In advance longwall mining, the safety of mine network, production rate, and consequently, economic conditions of a mine are dependent on the stability conditions of gate roadways. The gate roadway stability is a function of two important factors: 1) characteristics of the excavation damaged zone (EDZ) above the gate roadway and 2) loading effect due to the caving zone (CZ) above the longwall w...

in advance longwall mining, the safety of mine network, production rate, and consequently, economic conditions of a mine are dependent on the stability conditions of gate roadways. the gate roadway stability is a function of two important factors: 1) characteristics of the excavation damaged zone (edz) above the gate roadway and 2) loading effect due to the caving zone (cz) above the longwall w...

Based on techniques of close upper protective coal-rock layer mining, relieved gas extraction, and underground gangue washing-discharging-backfilling, this paper initiates the concept of mixed fully-mechanized coal mining, which combines a solid backfilling method and a caving method (hereinafter referred to as “backfill and caving mixed mining”). After the principle and key techniques are intr...

There are various criteria that need to be examined alongside each other when designing a longwall mining system. Challenges such as determination of the supported roof width, support system design, caving height determination, lateral or chain pillar size determination, and optimum support design for the main gate and tail gate roadways have to be tackled for this aim. Three-dimensional analys...

The paper begins by outlining the role and importance of coal as a source of energy and in the steel industry. It briefly describes the longwall method of working together with the conventional machinery used in the method. A mathematical model is then proposed that shows the relationship between the gradient of the coal seam, that of the face and the entries to the panel. Determination of a mo...

In order to reduce fire hazards caused by spontaneous combustion in longwall gob areas, a computational fluid dynamics (CFD) study is being conducted by National Institute for Occupational Safety and Health (NIOSH) to simulate the spontaneous heating of coal in longwall gob areas. A CFD model was first developed to model the spontaneous heating process in a two longwall panel district using a b...

An unmanned mining technology for the fully mechanized longwall face automation production is proposed and studied. The essential technology will bring the longwall face production into visualization through the VR (Virtual Reality) and AR (Augmented Reality) combination. Based on the visual theoretical model of the longwall face, the combination of virtual and reality, the real-time interactiv...

As more easily mined deposits are depleted, the reserves are becoming more limited and less favorable. Deposits of coal or trona that are being longwall mined are deep and are getting deeper. Coal bursts and bumps frequently occur within development entries in longwall mining of deep mines due to high stresses. This paper presents a novel patented longwall mining layout “Longwall Mining with Sp...

This paper describes recent advances in the development of an integrated inertial guidance system for automation of the longwall coal mining process. Significant advances in longwall automation are being achieved through an industry sponsored project which targets productivity and safety benefits. High performance inertial navigation systems are being successfully employed to accurately measure...

Reduction in the recovery time required and improvements in safety during a longwall face move have compelled coal mine operators to examine and use predriven longwall recovery rooms. The recovery entry is developed at the longwall stop position and supported ahead of time so that the required combinations of standing and internal supports can be installed before the longwall face approaches. A...