专业英语.docx

1、专业英语河 南 理 工 大 学 自 编 教 材专 业 英 语安全工程专业（学生用书）高建良 王云刚 编崔洪庆修改安全科学与工程学院2011年9月contentsPart Mine Ventilation 1LESSON 1 Introduction to Mine Ventilation 1LESSON 2 Energy Changes in Fluid Flow 3LESSON 3 Face Ventilation 5LESSON 4 Mechanical Ventilation 8LESSON 5 Mine Ventilation Systems 10LESSON 6 Fundamenta

2、ls of Ventilation Network Analysis 12Part Mine Safety 15LESSON 7 Mine Gases 15LESSON 8 Coal Seam Methane 17LESSON 9 Open Fires 19LESSON 10 Spontaneous Combustion 21LESSON 11 Methods of Dust Control 23Part Other Topics 25LESSON 12 Mine Drainage 25LESSON 13 Mine Rescue Operations 28LESSON 14 Survival

3、Program 30LESSON 15 Origin of Coal 32LESSON 16 History of Coal Mining 33LESSON 17 Accident Prevention Principles 34 Part Mine VentilationLESSON 1 Introduction to Mine VentilationIntroductionMine ventilation involves the control of the atmospheric environment. This requires control of the air quality

4、 and air movement to satisfy the requirements for the health, safety and comfort of mine workers. Minimum standards are set out in the various states mines regulation. Some are descriptive, specifying the standards required (eg. Victoria), and some are prescriptive, detailing exactly how the standar

5、ds are to be achieved (eg. W.A.).Purposes of Mine VentilationProperly engineered control of the mine atmosphere is required to:provide fresh air (oxygen) for men to breatheprovide a source of oxygen for internal combustion engines in machinerydilute atmospheric contaminants to acceptable levelsmaint

6、ain temperature and humidity within acceptable limitsremove atmospheric contaminants from the mine.Historical Development Mine ventilation is twofold in purpose: first, it maintains life, and secondly it carries off dangerous gases. The historic role of ventilation was to provide a flow of fresh air

7、 sufficient to replace the oxygen consumed by the miners working underground. Todays mine ventilation primarily deals with noxious gases (mainly generated by trackless equipment underground).In the past, mining occurred nearthe surface where natural light and ventilationwas available. Fires were use

8、d to draw fresh air into the mine and exhaust shafts vented the hot smoke out of the mine.Long before coal was mined in North America, collieries in Europe were sunk with dual entrances; one through which air flowed into the mine and another through which air flowed out. Initially, mine ventilation

9、was assisted by underground furnaces, which used the practical principle that the updraft of a fire caused a suction which drew air out of the mine and this air was replaced by air which was pulled in to fill the opening.Canaries are said to have been used to detect gas in coal mines in the early st

10、ages of coal mining. This sensitive bird would be taken into the workings and, if it perished, the colliers would immediately leave the mine.However, before the 1870s, managers and qualified persons were using safety lamps to detect gas. These safety lamps soon replaced oil lamps and open flared can

11、dles as a source of working light.Soon, small hand-turned fans were used to blow out gas from working places into main air currents. Trap doors were strategically placed as part of the ventilation system to guide the flow of air to or from selected areas. Trapper boys were posted at the busier doors

12、 to open them for the passage of coal, materials and men. Air courses were frequently cut through coal and rock. In the 1920s the hand-turned fans were replaced with air-powered small turbine fans. Large fans of the suction type were placed on the surface and gradually increased in size. Air from su

13、rface compressors was piped into the mine to power machinery and to assist in ventilation.Properties of AirThe constituents of air are:ConstituentVolumeMass %Nitrogen (N2)78.0975.53Oxygen (O2)20.9523.14Carbon Dioxide (CO2)0.03 0.04Rare Gases (Ar, H2, He, etc.)0.93 1.28Atmospheric Pressure at any poi

14、nt is due to the weight of air above it, and varies with altitude (which determines the height of the air column), and air density (which is determined by temperature and moisture content). Standard atmospheric pressure is taken as 760mm of Hg, (101.3kPa) at mean sea level, and it varies by about lk

15、Pa for every 90 m increase or decrease in altitude.Atmospheric temperature is normally given according to the Celsius scale (C), but the Kelvin scale (K) may be used.0K=-273C(absolute zero)273K=0C(freezing point of water)373K=100C(boiling point of water)Air is a colorless, odorless, tasteless gas mi

16、xture which supports combustion and life. In mine ventilation we are usually dealing with an air/water vapor mixture which has different thermodynamic properties to dry air. The density of dry air is 1.21 kg/m at standard atmospheric pressure (101.3kPa) and temperature (15C).New Words and Expression

17、smine ventilation 矿山通风internal combustion engine 内燃机dilute 冲淡, 变淡, 变弱, 稀释contaminant 污染物noxious 有害的exhaust shaft 出风井colliery 煤矿sink 挖掘suction 吸入, 吸力, 抽气, 抽气机, 抽水泵, 吸引canary 动金丝雀, 淡黄色trap door 通风门trapper 设阱捕兽者, 矿矿井风门开关管理员moisture content 湿度thermodynamic 热力学的, 使用热动力的LESSON 2 Energy Changes in Fluid Fl

18、owMine Ventilation is normally an example of a steady flow process, that is, one in which none of the variables of flow changes with time. Transition and loss in energy are involved in such a process, and it is important to understand their nature and to be able to express them mathematically. Energ

19、y changes are basic to the calculation of the mine quantity and head, one of the ultimate objectives of mine-ventilation engineering. An expression relating the energy variables may be developed as follows.The total energy at any section in a moving fluid consists of the sum of the internal static,

20、velocity, potential, and heat energies at that section. Assume a real fluid moving in a conduit, and consider the energy changes that occur between any two sections in the system. The heat changes is generally negligible compared to the other terms, except in deep mines or ones naturally ventilated,

21、 and the addition of mechanical energy is usually considered separately. Omitting these terms for now, the total energy at section 1 equals the total energy at section 2, plus the flow energy losses occurring between 1 and 2： (total energy)1 = (total energy)2 +(flow energy losses)1-2 (1)Or substitut

22、ing expressions for the various energy terms and disregarding the minor change in internal energy, the following general energy equation for fluid flow results: (2)Where: , - static energy; , -velocity energy; Z1, Z2 -potential energy; H1-2 -flow energy loss.Equation 2 is recognized as the familiar

23、Bernoulli equation, applicable to all fluid-flow processes. In this form, it applied only to an incompressible fluid, which air is assumed to be in nearly all mine ventilation because of minor changes in air density.Each term in the equation is actually a specific energy, in unit of m.kg/kg, or m. S

24、ince m is a measure of fluid, head these terms can also be referred to as pressure heads or simply heads. In dealing with air, it is customary to employ mm of water rather m of an air as the unit of head.Accepting the equivalency of specific energy and head, the general equation as written in Eq.1 c

25、an also be expressed: (3)Where: Ht total head; and Eq.2 can be expressed: Hs1+Hv1+Hz1=Hs2+Hv2+Hz2+H1-2 (4)Where Hs is static head, Hv is velocity head, and Hz is elevation or potential head, all heads have the unit of mm water.These versions of the Bernoulli energy equation (Eq.2 and 4) are both bas

26、ic and general and the most useful to employ in mine ventilation. In relation the static velocity, potential, and total heads plus the losses flow, the energy equation permits writing of an expression encompassing all flow variables between any two points in the ventilation system. These points may

27、be selected at the beginning and end of the system (the entrance and discharge of mine for the air circuit), enabling the calculation of the characteristics for the entire system (the mine heads).New Words and Expressionshead 液压，气压：液体或气体产生的压力；压差static energy 静压能velocity energy 动能potential energy 位能、

28、势能incompressible fluid 不可压缩流体LESSON 3 Face VentilationUnless the air is properly distributed to the face, the mine ventilation system is not performing its primary function. While it has always been recognized that this last part of ventilation is the most import, it is also the most difficult to ac

29、hieve.There are basically two methods of ventilating the blind entries ahead of the last open crosscut: the use of line brattices or the installation of auxiliary fans. Each technique has its defenders as well as its outspoken critics.Line BratticesThe line brattice is essentially a space divider or

30、 temporary partition made of an impervious material that is installed and maintained very carefully and kept as close to the face as possible. Its purpose is to guide the airflow through the face area and last open crosscut and into the return. Brattices were formerly (and to some extent still are)

31、made of untreated jute, but nylon reinforced plastics and similar materials are more commonly used in them today. While the more effective material is invariably higher in initial cost, it results in lower overall expense in that it allows for greater reuse and less air leakage.The line brattice is

32、installed so as to split the heading longitudinally and thus provides an inlet as well as a return from the face to the last open crosscut. Since the mining machine must have room to maneuver on one side of the brattice, it is not practical to split the entry evenly, so a wide side is provided for the machine. The air may be broug