1、 1 Research of dragline application in Shenhua Group opencast mines ABSTRACT:Dragline application is an advanced technique for opencast mining, which is integrated with mining, transportation and earth discharge. It can directly discharge the stripping earth into the earth stockyard. This technique
2、enjoys the advantage of large production capacity, cost effective and the shallow-burden opencast Mining. This article summarizes the dragline application in Heidaigou Opencast Mine, including the dragline type the analyses of the mining parameter and cast blast technique and economic and technologi
3、cal analyses, and also introduces the dragline application in Haerwusu Opencast Mine. The two examples witness the availability of the dragline used in Chinese opencast mines and its potential application as well. 1 QUESTION Coal is the major consumption energy in China. In recent years, the coal re
4、covery at state-owned main coalmines, state-owned local coalmines and country coalmines in our country is 50%, 30% and 15% respectively. The recovery of our coal resource is low, for underground mining methods hold much more proportion. Why surface mining with higher recovery is not developed univer
5、sally? Analysis founds that is related much to technology of surface mining .The railway transport technology was employed mainly in 60s,shovel-truck technology was developed in 80s. But shovel-truck technology has brought high production costs for a long time past because of many influence from fue
6、l cost, mining depth, working bench length, haulage distance to the dump yard, etc. Furthermore, this surface mining technology, which 2 working bench length is no more than 1.5 km, designed capability is no more than 15 mt, is not competitive in the market, so a new surface mining technology is urg
7、ently needed. The dragline stripping application is an advanced mining technology in the world, which integrates with three operations of digging, transport and dumping, can strip the overburden and dump at the spoil side of the mined-out area. This application is in worldwide use nowadays, for its
8、easier mining method, no restriction of working bench length. Centralized operation, higher efficiency and especial advantages to almost flat-bedded deposit, 2 RESEARCH OF DRAGLINE APPLICATION IN ZHUNGEER COALMINE Shenhua Group Zhungeer Energy Co. Ltd, is an extra-large-size comprehensive energy ent
9、erprise integrated with Heidaigou Coalmine and an integral preparation plant with an annual output of 12,000,000 tons each, a mine-mouth power plant with an installed capacity of 2100 MW and a first-degree single-track electric railway of 264 km long straight, and all facilities and equipments of th
10、e company are first-class and modern. With the development and industry reforms, the company gradually started to develop in a steadier and faster way. In order to match with requirements of the ambient electricity marketing, our company planned to expand the capability of exiting mine from 12 mt/a
11、to 20 mt/a, then we started the dragline application research in Heidaigou Open pit since 2002. Here we take Heidaigou Opencast Coalmine as an example, mainly introduce the machine model selection, operation parameter analysis, cast blast technology and economic benefit. 2.1.Availability of dragline
12、 application in Heidaigou Opencast Coalmine 3 In Heidaigou Opencast Coalmine, the thickness of surface soil is about 49 meters, rock layer about 56 meters and coal seam about 28.8 meters. The surface soil is to be stripped by bucket wheel excavator continuous system； rock and coal by shovel-truck sy
13、stem. The rock layer thickness ranges from 50 to 70 meters, with a lot of fractures, hardness of the rock f= 3 5. The coal type is lignite with features of low sulfur, extra low phosphorus, medium ash and high ash fusion point； the average calorific value is 19223-22154 J/g (4588 5288 cal/g), well q
14、ualified for power. The average thickness of the main minable coal seam (No. 6 coal seam) is 24 meters, the slope is no more than 3 5, and the hardness of coal f = 1-3. Considering the coal deposit and rock condition, cast blast and dragline application will be a very suitable stripping method for t
15、he mine. The dragline can be located at the top of the coal floor, rock above coal top floor can be dumped into the inner dump, the left rock and the top losses still employs the original mining technology 2.2 Dragline stripping operation Dragline can be applied in four ways. The mine chooses one of
16、 them. To make a dragline stand on the extended platform leveled by a bulldozer after blasting, and dump the overburden into the mined-out area, refer to Figure1. 2.3 Stripping parameters are defined as follows 2.3.1 coal mining working bench length The minimum coal mining working bench length is related to the production scale. Coal seam thickness coal seam density and working bench advance speed, the calculation formula is detailed as below: Lmin = M/(V h r d) = 2002 m
