采礦外文翻譯---煤與瓦斯突出礦井無人工作面開采保護(hù)煤層的研究

1、<p><b>　　英文原文</b></p><p>　　Study on mining the protective seam with the manless working face in coal and gas outburst mines</p><p>　　Fang Xin-qiua,b, Zhao Jun-jiea,b, He Jiea,b,

2、</p><p>　　aSchool of Mines, China University of Mining & Technology, Xuzhou 221116, China</p><p>　　bState Key Laboratory of Coal Resources and Safety Mine, Xuzhou 221008, China</p>&l

3、t;p>　　Abstract: In order to solve the problems of backward equipments, low recovery, security issues, high mortality in the coal industry, the technology of manless working face in mine which combined the traditional

4、mining process with the automatic technology is proposed based on the scientized mining, meanwhile, the idea of exploiting the protective seam in the coal seam group of the coal and gas outburst mines with manless workin

5、g face technology is also proposed so as to liberate other high gas c</p><p>　　Key words: scientized mining; coal seam group; protective seam; manless working face; gas extraction</p><p>　　Intro

6、duction</p><p>　　The scientized mining means mining the coal with the highest efficiency on the precondition of safety and environment friendly [1]. China’s coal output is very big, the advanced mining machi

7、nes must be used in order to adapt to the construction of modern mine, furthermore, the manless working face should also be used in some difficult conditions such as thin coal seam or coal and gas outburst seam. Although

8、 the mining technology develops rapidly, the overall level is still relatively backward. I</p><p>　　2. Mining the protective seam in high outburst mines</p><p>　　The coal seam group is one chara

9、cter of the high gas mining area in china and the permeability of coal seam is very low [4]. Therefore, gas is the primary factor which prevents this kind of mines from safety and high efficiency.The protective seam mini

10、ng is widely used in these high outburst mines in China so as to solve this problem. In addition, this is the most scientific method to prevent the regional gas outburst under the condition of mining the coal seam group

11、in high outburst mines [5, 6</p><p>　　When there is a coal seam group in the gas outburst mine, the no-outburst seam or little-outburst seam will be firstly exploited, and this kind of coal seam is called th

12、e protective seam. The original equilibrium state of stress will be broken after the protective seam is exploited. Besides, with the development of roof and floor, the strata stress will be redistributed. The roof strata

13、 can be divided into caving zone, fractured zone, and bending zone [7], the floor strata will generate floor he</p><p>　　The practice of mining the protective seam shows that the gas permeability of the uppe

14、r outburst-relieved seam increases 1000-3000 times, while that of the lower outburst-relieved seam increases about 1000 times. This provides a good chance for gas extraction. So the effect of the increased gas permeabili

15、ty should be fully utilized to extract the gas by arranging kinds of drillings or roadways which not only ensures the safety of mines but also guarantees the extracted green and efficient gas en</p><p>　　(1)

16、 Extracting the gas by ground surface drilling. This method is applied successfully in America [10], besides,Huainan, Huaibei, and Tiefa mining bureaus also made some tests or applications [11]. Although they have got so

17、me effect, the stability of the drillings are not very well so that they are broken before the expected life for the different geological conditions between China and America and the influence of the movement of the over

18、lying strata.</p><p>　　(2) Arranging some drillings and roadways in the coal seam or strata to extract the gas which is the main method widely used in solving the gas outburst problem.</p><p>　　

19、3. Analysis of the feasibility and application in manless working face</p><p>　　3.1. Analysis of the feasibility</p><p>　　The modern manless working face is proposed with the principle of scient

20、ized mining and comprehensive utilization of coal resources [12]. Based on the concrete conditions of China, we analyze the feasibility of manless working face:</p><p>　　The gas emission of the thick and med

21、ium-thickness coal seam is more thinner than coal seam, so the thin coal seam is the first choice as protective seam. At present, although the mining degree of chanization and automationin thick and medium-thickness coal

22、 seam is relatively high, but in thin coal seam is relatively backward. Blasting mining is the main method of mining the thin coal seam, on the one hand, the mining production rate is low and the partial coal resource is

23、 lost [13]. On the othe</p><p>　　Based on the system model of the manless working face, we make some integrated innovations on the modern technology and analyze the needed technology of every subsystem such

24、as self-positioning and automatic navigation</p><p>　　technology of the shearer, automatic vertical steering technology of the shearer, automatic recognition technology between coal and strata, electro-hydra

25、ulic control technology of the hydraulic support, automatic traction technology of the scraper conveyor, two-way communication technology of high-speed in the underground, component based coalmine software as well as the

26、 model technology, database technology and multi-sensor technology.</p><p>　　After being combined with these technologies, the manless working face technology can greatly improve the mining rate and promote

27、the security.</p><p>　　Coal is the main energy resource in China, the healthy development of the coal industry is related to the energy security and economic sustainable development of China. The coal is non

28、-renewable resource and the service life of the mine is certain. If the thin coal seam can be exploited through the existing production system, the recoverable reserves will be increased, and then the economic benefit wi

29、ll also be increased.</p><p>　　At present, gas explosion has the highest proportion in all kinds of the coal mine accidents in China. There were 182 coal mine accidents in 2008, the death toll was 778. So th

30、e preventing of gas accidents shoulders heavy responsibilities.</p><p>　　3.2. Application</p><p>　　Based on the scientific mining, exploiting the protective seam with manless working face is pro

31、posed combined with these analyses in coal seam group of the coal and gas outburst mines. After the gas in the coal seam group is released, it can be extracted by the reasonable drillings. It is a win-win method, not onl

32、y will the frequent gas overrun, frequent gas accidents and the limitation of scale be solved, but also the problems of great difficulty in mining and low mining rate. Furthermore, the </p><p>　　extraction o

33、f coal and gas.</p><p>　　4. Example of mining designs in manless working face</p><p>　　4.1. Condition of text area</p><p>　　The Shaqu coal mine of the HUAJIN coking-coal company is

34、a coal and gas outburst mine. The absolute outflow of gas is 344.43 m3/min and the relative outflow of gas is 61.8 m3/t. It is a short distance coal seam group and the minable seams are the second, third, forth and fifth

35、 coal seam (Fig.1).</p><p>　　Fig. 1. Columnar section of coal and strata seam</p><p>　　The article 193 of coal mine safety regulation prescribes that the protective seam should be exploited pref

36、erentially when mining the coal seam group in coal and gas outburst mine. The article 198 prescribes that the gas of liberated seams should be extracted when mining the protective seam [14]. So the Shaqu coal mine consti

37、tutes the regional gas government which the third coal seam is mined to liberate the second and third coal seam in order to guarantee the safety and efficient mining.</p><p>　　4.2. Design of the working face

38、</p><p>　　The 13301 working face of Shaqu coal mine is chosen as the experimental area where U-type ventilation is designed in line with reducing the amount of roadway as well as decreasing the gas concentra

39、tion. In order to extract the gas of 13301 working face, the inclined dense drillings are bored in the return airway by the ADR 250 High-Efficiency drilling rig (Fig.2).</p><p>　　Fig. 2. Schematic diagram of

40、 gas extracting drilling in 13301</p><p>　　The aperture of the drilling rig is 250 mm and it’s very rare home and broad. The big aperture which is beneficial to extract the gas can greatly improve the extrac

41、tion rate. The length of the working face is 150 m and the length of the drilling is 140 m, arranging the drilling every 6 m in the direction of tendency and all the drillings are parallel.The distance between open-off c

42、ut and the first drilling is 15 m and the last one is at the stopping line, so there are altogether 160 drillings. U</p><p>　　The shape of the roadway is rectangle using the combined support of anchor, metal

43、 net and W-type steel band to support the roadway. Both the width of the conveyance roadway and return airway is 4.5 m, the height of the roadway is 2.8 m.</p><p>　　4.3. Selection of the equipments in the wo

44、rking face</p><p>　　Choice of shearer</p><p>　　Fully automatic mining system of the plough is an effective way to realize high production and efficient [15]. The features of little depth-web, fa

45、st advance speed and high adaptability make it the first choice in mining the thin coal seam. In order to realize the high production, high efficient and high automation, the GH9-34ve/4.7 plough of the DBT Company is sel

46、ected combined with the concrete conditions in Shaqu coalmine. The rated power of this plough is 160/315 kW and the production capaci</p><p>　　Choice of hydraulic support</p><p>　　Following the

47、principle of reliable system and the priority of domestic equipment, we select the Germany PM4 control unit combined with the domestic hydraulic support. The concrete type is ZY4800/6.5/16.5D of the middle hydraulic supp

48、ort and ZZ5800/16/30 of the terminal hydraulic support.</p><p>　　Choice of scraper conveyor</p><p>　　The current proportion between the scraper conveyor and shearer is 1.2~1.4:1. In order to exe

49、rt the capacity of the scraper conveyor, we select the PF2.30/732 scraper conveyor.</p><p>　　The capacity of the fully mechanized mining equipments should be based on the capacity of the shearer.Meanwhile, t

50、he principles of the speed-matching, connection-matching, etc. should also be taken into consideration.Then the main equipments of the working face can be determined (Table 1).</p><p>　　Table 1. Main equipme

51、nts of the working face</p><p>　　4.4. Mining technology</p><p>　　By means of the combined auto-control shearer and hydraulic support, the automatic coal cutting, automaticadvancing support and t

52、he linkage of the scraper conveyor can be realized, meanwhile, using the centralized control and sequential start-stop to realize the automatic control (Fig.3).</p><p>　　Fig. 3. Technological process</p&g

53、t;<p>　　4.5. Design of gas extraction</p><p>　　4.5.1. Numerical simulation</p><p>　　The numerical simulation software UDEC is adopted to provide the theoretical basis for the gas extracti

54、on so that the gas outburst of the first mining seam and the contiguous seams can be governed well. Taking the strike section</p><p>　　of the 13301 working face as field model, then, the numerical model can

55、be built length of tendency × length of inclination=250×55 m, the elevation of the third coal seam is 450 m. The left hand, right hand and lower boundaries of the model are displacement boundary. The left and r

56、ight boundaries constrain the displacement in x-direction and the lower boundary constrains the displacement in y-direction (Fig.4).</p><p>　　Fig. 4. Simulation model</p><p>　　The change law of

57、the mining influence, height of fractured zone in the roof and floor and the change law of fractured zone with the advancing of working face are simulated in this numerical simulation. The results are as follows:</p&g

58、t;<p>　　When the advance distance is 40 m (Fig.5), basic roof begins to collapse. The height of the caving zone is about 6m and the strata near basic roof are destroyed by tension. The vertical fracture and interl

59、ayer fracture are generated in the overlying strata and the height of breaking though fracture is about 10 m. There is some deformation in floor of the goaf, which can be seen from the displacement curve of the floor tha

60、t the maximum compression deformation is 7 m around the lateral of cutting </p><p>　　Fig. 5. Movement status and fracture distribution of </p><p>　　surrounding rock (a) when the excavation dista

61、nce</p><p>　　is 40 m; (b) when the excavation distance is 60 m</p><p>　　4.5.2. Design of the gas extraction arrangement</p><p>　　It can be obtained from the theoretical analysis and

62、 numerical simulation that the second coal seam is in the fractured zone of the third coal seam and the forth coal seam is in the deformation zone of the third coal seam. So the gas can be largely extracted after arrangi

63、ng some drillings in the fractured zone of the roof and deformation zone of the floor.</p><p>　　The DDR1200 directional drilling rig which introduced by the Shaqu coal mine can be controlled artificially to

64、drill along the roof or floor at some angle. The aperture is 170 mm and the drilling length is 1200 m. The 13301 working face is selected as the experimental area and the concrete schemes are:</p><p>　　Four

65、drillings were born when they reached the forth coal seam, then, boring in the forth coal seam. These drillings can extract the pressure relief gas of forth coal seam and the gas between the third and the forth coal seam

66、.</p><p>　　Four drillings were born when they reached the upside of the second coal seam and the vertical distance between the second coal seam and the drillings is 3 m, then, bore along the direction of par

67、allel to second coal seam.So the second coal seam can be liberated. The profile drawing of the drillings is shown in Fig.7.</p><p>　　So the coal seam group can be liberated and the problem of gas outburst ca

68、n also be well solved.</p><p>　　Fig. 7. Schematic diagram of profile in 13301</p><p>　　5. Conclusions</p><p>　　The problems of coal mining in China are researched and the manless wo

69、rking face is proposed, which is based on the automatic conditions of fully mechanized mining coal face ,It is an important way to realize the sustainable development of coal industry.</p><p>　　The idea of m

70、ining the protective seam with the manless working face in the coal seam group of the coal and gas outburst mines is proposed. Not only the problem of hard-mining in coal and gas outburst mines will be solved but also th

71、e problem of hard-mining in thin coal seam can be solved.</p><p>　　Working face design, equipments selection and mining technology design are carried out to the third coal seam based on the concrete conditio

72、ns of the Shaqu coal mine.</p><p>　　Feasibility of making the third coal seam as protective seam is verified based on the theoretical analysis and numerical simulation and it provides a new thought to the sa

73、fe and high efficient coal mining.</p><p>　　Acknowledgements</p><p>　　Financial support for this work, provided by the National Natural Science Foundation of China, is gratefully acknowledged.&l

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86、03) 17-20.</p><p><b>　　中文譯文</b></p><p>　　煤與瓦斯突出礦井無人工作面開采保護(hù)煤層的研究</p><p>　　方新秋，何杰，趙俊杰</p><p>　　中國礦業(yè)大學(xué)礦業(yè)工程學(xué)院， 煤炭資源與安</p><p>　　全開采國家重點(diǎn)實(shí)驗(yàn)室，江蘇徐州 2210

87、08</p><p>　　摘要：為解決煤礦開采技術(shù)、裝備普遍落后，煤炭資源回收率低、安全以及死亡率高的問題，基于科學(xué)采礦的理念，提出高度自動化與傳統(tǒng)綜采工藝相結(jié)合的無人工作面開采技術(shù)，同時提出了在煤與瓦斯突出煤層組的無人工作面開采保護(hù)煤層的概念，以便釋放其它高瓦斯煤層。有煤與瓦斯突出的沙曲煤礦正在開采作為保護(hù)煤層的3號煤，同時進(jìn)行巷道、設(shè)備選型和開采方法的設(shè)計。最后，通過理論分析和數(shù)值模擬，設(shè)計出瓦斯抽放的方案，

88、對工業(yè)試驗(yàn)的3號煤層提供了科學(xué)的依據(jù)和方法。</p><p>　　關(guān)鍵詞：科學(xué)采礦；煤層組；保護(hù)層；無人工作面；瓦斯抽放</p><p><b>　　1 簡介</b></p><p>　　科學(xué)采礦是指在安全和環(huán)保的前提下最高效率的開采技術(shù)。中國的煤炭產(chǎn)量很大，先進(jìn)的采礦設(shè)備必須適應(yīng)現(xiàn)代礦山建設(shè)，此外，無人工作面也應(yīng)用在一些困難的條件下，如薄煤層

89、或煤與瓦斯突出煤層。雖然開采技術(shù)發(fā)展迅速，但是整體水平還是比較落后的。為了解決這個問題，改善現(xiàn)狀及保持煤炭資源的可持續(xù)利用，作者提出了在煤與瓦斯突出礦井中無人工作面開采保護(hù)煤層。以釋放其它被保護(hù)煤層的瓦斯，達(dá)到減少瓦斯?jié)舛鹊哪康模瑥亩幸粋€安全的采礦工作環(huán)境。最后，達(dá)到安全、高效的綠色開采。</p><p>　　2 開采高突出礦井保護(hù)層</p><p>　　煤層組是中國高瓦斯采礦區(qū)域的特征

90、之一，同時煤層的滲透率很低。因此，瓦斯是妨礙這類礦井安全和高效開采的主要因素。保護(hù)煤層開采已被廣泛應(yīng)用于中國這些高突礦井以解決這個問題。此外，在高突礦井開采煤層組條件下，這是防止區(qū)域瓦斯突出的最科學(xué)的方法。</p><p>　　在有煤與瓦斯突出危險的礦井有一煤層組時，首先開采無突出煤層或基本無突出煤層，這類煤層叫做保護(hù)層。 保護(hù)層開采后，原巖應(yīng)力被破壞。此外，隨著頂板和底板的變形，應(yīng)力將會重新分布。頂板被劃分成垮

91、落帶，裂隙帶，彎曲下沉帶，底板會隆起和斷裂。斷裂包括層狀節(jié)理和交叉裂紋，底板斷裂發(fā)展的程度與各巖層之間的距離成反比。根據(jù)煤礦的具體地質(zhì)條件，通過層與層之間的相對距離，瓦斯抽放的方法可以分為短距離，中等距離，長距離，它為煤層組瓦斯治理提供了理論依據(jù)。</p><p>　　實(shí)踐證明，開采保護(hù)層會使上部煤層瓦斯透氣性增加1000~3000倍，同時會使下部煤層瓦斯透氣性增加大約1000倍。這為瓦斯抽放提供了很好的條件。所

92、以瓦斯透氣性增強(qiáng)的效果可以通過各種鉆孔或巷道布置，充分利用于提取瓦斯，不僅可以保證礦井安全生產(chǎn)，而且可以保證被高效提取的綠色瓦斯能源用于工業(yè)。具體方法如下：</p><p>　?。?）地面抽采瓦斯。該方法成功地應(yīng)用于美國，除此之外，淮南、淮北和鐵法局也測試或應(yīng)用過。盡管取得了一些成果，但是鉆孔的穩(wěn)定性不是很好，打破了以往在中國與美國間不同地區(qū)條件的服務(wù)年限和上覆巖層的運(yùn)動的影響。</p><p

93、>　?。?）利用煤層中鉆孔和巷道的布置提取瓦斯的方法廣泛應(yīng)用于解決瓦斯突出問題。</p><p>　　3 無人工作面可行與應(yīng)用型分析</p><p><b>　　3.1可行性分析</b></p><p>　　現(xiàn)代無人工作面的提出以科學(xué)采礦和綜合利用煤炭資源為原則。根據(jù)中國的具體情況，分析了無人工作面的可行性：</p><

94、;p>　　厚煤層和中厚煤層瓦斯涌出比薄煤層困難，所以薄煤層是保護(hù)層的第一選擇。目前，盡管厚煤層和中厚煤層的自動機(jī)械化開采程度相對較高，但是在薄煤層卻很低。炮采是薄煤層開采的主要方法，一方面，采出率低，局部的煤炭資源丟失嚴(yán)重，另一方面，工作面環(huán)境惡劣和勞動力強(qiáng)度大?？紤]到這些不利因素，許多煤礦放棄開采薄煤層。這種行為不僅嚴(yán)重浪費(fèi)了煤炭資源，而且縮短礦井的服務(wù)年限，同時，它也限制了煤與瓦斯突出礦井煤層群開采保護(hù)煤層的發(fā)展。所以在采礦領(lǐng)

95、域的當(dāng)務(wù)之急是發(fā)展高產(chǎn)高效礦井開采技術(shù)。</p><p>　　基于無人工作面系統(tǒng)模型，做了一些綜合創(chuàng)新的現(xiàn)代技術(shù)，分析了各子系統(tǒng)的所需的技術(shù)，如自我定位和自動導(dǎo)航技術(shù)、自動剪機(jī)的垂直轉(zhuǎn)向技術(shù)、電煤巖層間的自動識別技術(shù)、液壓控制技術(shù)的支持，自動牽引技術(shù)的刮板輸送機(jī)、雙向通信技術(shù)在地下，高速基于組件的煤礦軟件以及模型技術(shù)、數(shù)據(jù)庫技術(shù)和傳感器技術(shù)。</p><p>　　這些技術(shù)相結(jié)合后，無人工作

96、面技術(shù)能夠較大地提高開采率和促進(jìn)安全開采。</p><p>　　煤是中國最主要的能源，在中國煤炭行業(yè)的健康發(fā)展是與能源安全、經(jīng)濟(jì)的可持續(xù)發(fā)展相關(guān)的。煤炭是不可再生資源，煤炭使用年限是一定的。如果在現(xiàn)有的生產(chǎn)體系薄煤層可以被利用，可以增加工業(yè)儲量和經(jīng)濟(jì)利潤。</p><p>　　目前，瓦斯爆炸在中國各種各樣的煤礦事故占有最高的比例。2008年發(fā)生182起煤礦事故，死亡人數(shù)778。所以防止瓦斯

97、事故的責(zé)任重大。</p><p><b>　　3.2應(yīng)用</b></p><p>　　基于科學(xué)采礦，結(jié)合在煤與瓦斯突出礦井煤層組的分析，提出了無人工作面開采保護(hù)層。煤層組的瓦斯釋放后，可以通過合理的鉆孔提取。這是一個雙贏的方法，不僅可以解決瓦斯頻繁的涌出，頻繁的瓦斯事故與比例限制。而且可以解決開采難度很大和低開采率的問題。此外，綠色開采煤炭資源可以實(shí)現(xiàn)同步采出煤與瓦斯

98、。</p><p>　　4 無人工作面開采設(shè)計實(shí)例</p><p><b>　　4.1實(shí)驗(yàn)礦區(qū)條件</b></p><p>　　沙曲煤礦是煤與瓦斯突出礦井。瓦斯的絕對涌出量為344.43m3/min，相對涌出量為61.8 m3/min。屬近距離煤層組開采，可采煤層為2，3，4，5號煤。如圖1所示。</p><p><

99、;b>　　圖1 煤層柱狀圖</b></p><p>　　《煤礦安全規(guī)定》第一百九十三條規(guī)定，當(dāng)開采有煤與瓦斯突出的礦井煤層組時應(yīng)首先開采保護(hù)層。第一百九十八條的規(guī)定，當(dāng)開采保護(hù)層時必須釋放解放層的瓦斯。因此，沙曲煤礦首先開采3號煤，釋放2、3號煤的瓦斯，從而保證安全、高效開采。</p><p><b>　　4.2工作面設(shè)計</b></p>

100、<p>　　選取沙曲煤礦13301工作面作為實(shí)驗(yàn)點(diǎn)，該工作面設(shè)計成U型通風(fēng)，符合減少巷道瓦斯的濃度的要求。為了抽出13301工作面的瓦斯，通過250高效率鉆機(jī)分析了回風(fēng)巷中斜密鉆孔，如圖2所示。</p><p>　　圖2 瓦斯抽放孔布置圖</p><p>　　鉆機(jī)的鉆孔孔徑250mm，這在國內(nèi)是非常罕見的。有利于抽出瓦斯的大鉆孔可以極大地提高抽出率。工作面的長度150m，鉆孔