surface mining economic only when the coal seam is relatively

The speed, scale, and environmental and economic impacts of surface

Compared to other kinds of mining, coal mining receives more attention because coal is not only the most important fossil fuel resource contributing to rapid economic development but is also the ...

Dynamic Changes in Surface Damage Induced by High-Intensity Mining …

The compaction of caving gangue in goaf has an important influence on the surface subsidence and the distribution of mining stress. The mining coal seam is shallow (depth less than 200 m), the mining thickness of the coal seam is large at one time (mining thickness is 12.8 m), and the overlying strata are mostly weakly cemented strata.

Surface and Subsurface Coal Environments: From …

In addition to subsurface coal mining (i.e., underground mining), coal reserves can also be exploited via surface mining. Surface mining is a broad term that …

Coal Mining and Processing Methods

Surface Mining. In surface mining, the ground covering the coal seam (the overburden) is first removed to expose the coal seam for extraction.

WHAT IS COAL? COAL MINING

Coal is a fossil fuel created from the remains of plants that lived and died about 100 to 400 million years ago when parts of the Earth were covered with huge swampy forests. Coal is classi ed as a nonrenewable energy source because it takes millions of years to form. HOW COAL WAS FORMED. Surface mining is used when a coal seam is relatively ...

A REVIEW ON EXISTING OPENCAST COAL MINING …

capital costs involved with the large, usually imported, machinery [2]. Generally, surface mines are only economical when the coal seam is relatively close to the surface, and the recovery rate of coal is higher than underground methods. Surface coal mining operation can be thought of as consisting of two distinct stages, overburden

Environmental impact of coal mining and coal seam gas

The extraction of coal and coal seam gas (CSG) will generate produced water that, if not adequately treated, will pollute surface and groundwater systems. In Australia, the discharge of produced water from coal mining and related activities is regulated by the state environment agency through a pollution licence. This licence sets …

Surface Subsidence Prediction Method for Backfill Mining in …

The mining of shallow coal seams with hard roofs poses a threat to surface structures. In order to ensure the protection of these buildings, backfill mining is increasingly used in these types of coal seams. However, due to the lack of appropriate surface subsidence prediction methods, there are concerns about whether backfill …

Prediction of surface deformation induced by mining …

Since 2015, the goafs of coal seams K8 and K7 have primarily caused the deformation of coherent points pt4 and pt5 in the study area (shown in Fig. 2 ). The …

Optimization of concurrent mining and reclamation plans for single coal

China is the number one coal production and consumption country. The coal outputs exceeded 3 billion tons in 2010, accounting for 42 % of the global production (Wang 2009).However, mining and utilization of coal may cause serious environmental impacts such as coal waste disposal, poisonous gas emissions, land subsidence, landscape …

Geology 12 Flashcards | Quizlet

A _____ originates from an accumulation of terrestrial vegetation in an anoxic environment, like a swamp. During underground mining, the rock above a coal seam is supported by _____ Undergound coal-bed fires become a major problem once ignited, and they continue to burn by drawing in _____ from the joints and pore spaces of surrounding rock

Why Surface Mine

Surface mining through abandoned deep mines, recovering the blocks of coal that were left decades ago, is relatively common. Contour mining along the outer boundary of old deep mines has been a widespread practice for years. The advent of the highwall miner, which is a more productive successor to a coal auger, has encouraged this trend.

Surface Mining Methods and Systems | SpringerLink

8.1 Surface Mining Methods. Surface mining deposits can be primarily divided as follows: Relatively horizontally stratified deposits with thick or thin overburden. Stratified and vein deposits dipping at angles; greater than the angle of repose of the spoil so that overburden cannot be deposited within the pit.

Modelling the cumulative impacts of future coal mining and coal seam …

Modern mining methods for coal include surface and underground mining. Surface mining (also known as open cut, open cast, or mountaintop removal mining) is appropriate for seams that occur sufficiently close to the land surface that it is economical to remove the overburden in order to access the seam.

Highwall Mining

Highwall mining is a relatively new semi-surface and semi-underground coal mining method used to extract such remaining coal reserves after the economic ... Contour Mining When the coal seam ...

Surface subsidence and its reclamation of a coal mine

Underground mining leads to surface subsidence, vegetation degradation and environment damage. In order to mitigate such negative influences, this study focuses on subsidence characteristics and reclamation methods of the second coal mine in Zhaogu mining area. Due to high groundwater table at the mine, post-mining land is divided into …

7.3.3: Auger Mining | GEOG 000

In auger mining, auger holes are bored horizontally into the coal seam from the last contour cut at the high wall. As the auger rotates and advances forward, coal is cut and pushed out of the hole by the rotating action of the auger. The action is similar to that of a carpenter boring a large hole in wood using an auger bit, and that is where ...

Guidelines for the economic assessment of mining and …

5.14 Example of value estimates related to surface water impacts 81 ... Changes in prices relative to inflation are included, such as real changes in coal prices. Draft Guidelines for the economic assessment of mining and coal seam gas proposals | Oct 2015 | Page 7 The key steps to undertake a CBA are highlighted in box 1.1 and discussed in

Mine pressure behavior law of isolated island working face …

In order to study the mining pressure characteristics of the shallow buried coal seam with the same silo working face under the very close mining void zone and the overlying coal rock body, the ...

Guidelines for the economic assessment of mining and …

Submission: Guidelines for the economic assessment of mining and CSG 9 Groundwater and surface water Overall, the considerations for groundwater and surface water completely miss the mark in terms of an analysis of the economic impacts due to proponent's intended water use or water source interference. There appears to be no …

Risk assessment and prevention of surface subsidence in …

In this article, an integrated system comprising deep mining, coal-gangue dressing, and underground backfill mining is proposed on the basis field-work. Analysis of the type, construction, and protection standards of the buildings resulted in the elaboration of numerical model aimed at studying the surface subsidence and deformation.

Dynamic structural evolution of overlying strata during shallow coal

Guo et al. [3] defined high-intensity mining as a high-yield and high-efficiency coal mining method in thick coal seams (more than 3.5 m) with large panel width (more than 200 m), fast advancing ...

Surface Coal Mining Methods in Australia

both equipment as integrated sy stems in Australia. Strip mining is ideally applied where the surface of the ground and the ore body itself are relatively horizontal and shallow and where a wide area is available to be mined in a series of strips (Westcott, 2004). Table 2 provides some examples of the Australian surface coal mines.

Coal Mining | EME 444: Global Energy Enterprise

Surface mining works only when the coal seam is near the surface. It is, however, usually more cost-effective than underground mining and requires fewer workers to produce the same quantity of coal. And the industry reports that 90% or more of the coal is recovered, a higher … See more

Impact of ground surface subsidence caused by underground coal mining …

According to the results of graphic constructions, the boundary of the impact zone of mining operations when mining the coal seam with longwall face No. 1065, which mines the coal seam c 10 v, is ...

Modelling the impacts of future coal mining and coal …

Extraction methods for coal include surface and underground mining. Surface mining (also known as open cut, open cast, or mountaintop removal mining) is …

Coal and Coal Mining

Coal Mining Methods (cont.) Surface mining methods: contour mining – used in steep, hilly terrain, following the contour of the hill; maximum economic stripping ratio is …

Prediction of surface deformation induced by mining thin coal seam…

The surface subsidence caused by mining coal seam K10 is about 0.80 m. Because of the early stopping of mining coal seam K10, the overlying strata induced by coal seam mining are nearly stable; thus, coal seam K10 is not considered in the final surface subsidence result. ... The calculation process is only a simple mathematical …

Economic and Technical Analysis of Thick Coal Seam Mining …

The findings of our study of No.5 coal seam in Shengli surface mine show that, the no.5 coal seam has numerous parting layer, thin coal seams, so 0.25 m is determined as the reasonable mining ...

Multi-seam coal mining

No. 2 and No. 4 seam. Multi-seam mining The mining of multiple seams has long been practised at the Khutala Colliery. By definition, 'multi-seam coal mining' is the mining of coal seams that overlay each other in a vertical depositional sequence. The seams are separated by rock strata known as parting3. The area of investigation for the new ...