爆炸危险性生产场所静电产生原因及防护措施.doc

/ / / / 爆炸危险性生产场所静电产生原因及防护措施生产工艺过程中产生的静电有时干扰正常生产和影响产品质量；有时会带来严重的危害；有时则会造成巨大的灾害。在一些危险的场所，仅是非常微弱的静电火花便可能引起迅猛的火灾和强烈的爆炸，甚至造成生命和财产的损失。此外，通过人体的静电放电还可能使人遭受电击而产生精神紧张、不安，对安全生产十分不利。因此，我们有必要了解静电产生的原因及可能造成的危害，并采取切实可行的防护措施。Production process in the process of electrostatic sometimes interfere with the normal production and affect the quality of the products; Sometimes will bring serious harm; Sometimes cause great disaster. In some dangerous place, is only very weak electrostatic spark may cause rapid and intense fire explosion, even cause loss of life and property. In addition, through the human body electrostatic discharge could also make people suffer from stress resulting from the shock, uneasy, very bad for safety production. Therefore, it is necessary to understand the causes of static electricity and may cause damage, and adopt feasible protection measures. 一、静电产生的原因分析A, the cause of static analysis 静电产生的原因很多，但主要可以从物质内部特性和外界条件的影响两个方面来说明。Electrostatic generation for many reasons, but mainly from the material properties and internal two aspects to illustrate the influence of external conditions. （一）内部特性(a) internal characteristics 第一，物质的逸出功不同。由于不同物质使电子脱离原来物体表面所需外界做的功（称为逸出功）不同，因此，当它们两者紧密接触时，在接触面上就会发生电子转移，逸出功小的物质失去电子而带正电荷，逸出功大的物质则得到电子而带负电荷。各种物质电子逸出功的不同是产生静电的基础。First, the work function of material is different. Because of different material electron out of the original surface outside to do the work required (called the work function), as a result, when they both close contact, in electron transfer occurs, the contact surface work function of small material lose electrons and positive, work function of material was negatively charged electrons. Various physical electronic work function is the basis of static electricity. 第二，物质的电阻率不同。静电的产生和物质的导电性能有很大关系，它以电阻率来表示。电阻率越小，导电性能越好。根据大量实验得出的结论，物质的电阻率小于106cm时，因其本身具有较好的导电性能，静电将很快泄漏。大于106cm且小于1010cm的物质，通常带电量是不大的，不易产生静电。大于1010cm且小于1015cm的物质最易带静电，是防静电工作的重点对象。如汽油、苯、乙醚等，它们的电阻率在大于1011cm且小于1015cm之间，静电很容易产生并积聚。但当电阻率大于1015cm时，物质就不易产生静电，可一旦产生静电，就难以消除。因此，电阻率的大小是静电能否积聚的条件。Second, the materials resistivity is different. The generation of static electricity and the conductivity of material has much to do, it said by resistivity. The resistivity is smaller, the better the performance of conductive. Conclusion based on a lot of experiments, the resistance of the material rate is less than 106 , cm, because of its itself has good conductivity, electrostatic leakage will soon. Greater than 106 , cm and is less than 1010 , cm, usually with electric quantity is not big, not easy to produce static electricity. Greater than 1010 , cm and is less than 1015 , cm material with most easily electrostatic, is the key of the anti-static work object. Such as gasoline, benzene, ether, etc., and their resistance rates in more than 1011 , cm and is less than 1015 , cm, static electricity is easy to generate and accumulate. But when the resistivity is more than 1015 , cm, material is not easy to produce static electricity, can once produced electrostatic, it will be difficult to eliminate. As a result, the size of the resistivity is electrostatic accumulation conditions. 必须指出，水是静电的良导体，但当少量水夹在绝缘油品中，因为水滴与油品相对流动时要产生静电，反而会使油品静电量增加。金属是良导体，但当它与大地绝缘时，就和绝缘体一样，也会带有静电。It must be pointed out that water is a good conductor of static electricity, but when a small amount of water in the insulating oil, because water droplets and oil flow relative to generate static electricity, it will increase the petroleum static electricity. Metals are good conductors, but when it is with the earth insulation, and insulators, also with static electricity. 第三，介电常数不同。介电常数也称电容率，是决定电容的一个主要因素。在具体配置条件下，物体的电容与电阻结合起来，决定了静电的消散规律，是影响电荷积聚的另一因素。对于液体，介电常数大的一般电阻率低。如果液体相对介电常数大于20，并以“连续相”存在及接地，一般来说，不管是输送还是储运，都不大可能积聚静电。Third, different dielectric constants. Dielectric constant is also called the permittivity, is a major factor decide the capacitance. Under the condition of the specific configuration, the object of capacitance and resistance, determines the electrostatic dissipation regularity, is another factor that influence the charge accumulation. For liquid, the dielectric constant of generally low resistivity. If the relative dielectric constant liquid is greater than 20 and exist in the continuous phase and the ground, in general, both transportation and storage, are unlikely to accumulate static electricity. （二）外部作用条件(2) external conditions 第一，紧密接触与迅速分离。两种不同的物质通过紧密接触与迅速分离的过程，将外部能量转变为静电能量，并贮存于物质之中。其主要表现形式除摩擦外，还有撕裂、剥离、拉伸、加捻、撞击、挤压、过滤及粉碎等。First, close contact with rapid separation. Two different substances by close contact with rapid separation process, the external energy into electrostatic energy, and stored in the material. Its main expression form in addition to the friction, there is tear, stripping, stretching, twisting, impact, compression, filtering and crushing, etc. 第二，附着带电。某种极性离子或自由电子附着在与大地绝缘的物体上，也能使该物体呈带静电的现象。人在有带电微粒的场（转载自论文之家，请保留此标记。）合活动后，由于带电微粒吸附于人体，因而也会带电。Second, adhere to live. One polarity ions and free electrons attached to the insulation on the objects of the earth, also can make the object with electrostatic phenomena. In a field with charged particles (reproduced since the paper home of , please keep this mark.) And after the activity, due to the charged particle adsorption to the human body, and therefore will be charged. 第三，感应起电。带电物体能使附近与它并不相连接的另一导体表面的不同部位也出现极性相反的电荷，这种现象为感应起电。Third, inductive electrification. Electrically charged objects to enable near and it is not connected to the other different parts of the surface of the conductor is appear the opposite charge polarity, the phenomenon of inductive electrification. 第四，极化起电。绝缘体在静电场内，其内部或表面的分子能产生极化而出现电荷的现象，叫静电极化作用。如在绝缘容器内盛装带有静电的物体时，容器的外壁也具有带电性，就是此原因。Fourth, the electric polarization. Insulators in electrostatic field, and its internal or surface molecules can produce the phenomenon of polarization and charge, called electrostatic polarization effect. Such as dressed in the insulated container with a static object, the walls of the container is charged, also is the reason for this. 二、静电的危害Second, the harm of static electricity 第一，静电火花引起燃烧爆炸。如果在接地良好的导体上产生静电后，静电会很快泄漏到大地中，但如果是绝缘体上产生静电，则电荷会越聚越多，形成很高的电位。当带电体与不带电体或静电电位很低的物体接近时，如电位差达到300V以上，就会发生放电现象，并产生火花。静电电位越积越高，在一定条件下导致火花放电，瞬时功率可达几十万千瓦，把电能转变为热能，静电放电的火花能量达到或大于周围可燃物的最小点火能量，而且可燃物在空气中的浓度或含量也已在爆炸极限范围以内时，就能立即引起燃烧或爆炸，造成人员伤亡和巨大的经济损失。First, the electrostatic spark burning explosion. If in good grounding conductor produce static electricity, static leakage to the earth soon, but if it is on insulator produce electrostatic, charge will gather more more, formed a high potential. When the charged body and not charged body or electrostatic potential low object approaches, such as the potential difference reached more than 300 v, discharge phenomenon occurs, and generate a spark. Electrostatic potential product higher and higher, under certain conditions lead to spark discharge, instantaneous power can reach hundreds of thousands of kilowatts, convert electrical energy into heat energy, the electrostatic spark discharge of energy around to or greater than the minimum ignition energy, fuel and fuel concentration in the air or when content is within the scope of explosion limit, can cause burns immediately or explosion, casualties and huge economic losses. 第二，电击。人在活动过程中，由于衣着等固体物质的接触和分离及人体接近带电体产生静电感应，均可产生静电。当人体与其他物体之间发生放电时，人即遭到电击。因为这种电击是通过放电造成的，所以电击时人的感觉与放电能量有关，也就是说静电电击严重程度决定于人体电容的大小和人体电压的高低。由于静电能量较小，太阳能代理所以生产过程中产生的静电所引起的电击不会对人体产生直接危害，但人体可能因电击坠落或摔倒而造成所谓的二次事故。电击还可能使人员产生精神紧张、不安，妨碍工作。Second, the electric shock. People in the process of activity, because the solid material such as clothing contact and separation and close to the charged body human body electrostatic induction, can generate static electricity. When the discharge occurs between human body and other objects, people or electric shock. Because of this shock is caused by discharge, so the feeling of electric shock people related to the discharge energy, that is static shock severity depends on the size of the human body capacitance and the body of high and low voltage. Smaller due to the electrostatic energy, so electric shock caused by static electricity generated in the production process does not produce direct harm to human body, the body may be caused by electric shock or fall fall so-called secondary accidents. Electric shock may also make staff produce mental tension, anxiety, interfere with work. 第三，危害生产设备。静电能吸引灰尘，影响生产中的电子元器件的正常工作；静电还能使操作人员充电电位最高达50kv，严重影响车间电讯设备、微电子元件、计算机等的正常工作，甚至放电造成这些设备的损坏，给安全生产带来巨大的危害。Third, the production equipment. Electrostatic attract dust, affect the normal work of the production of electronic components; Static electricity can also make the operation personnel charging potential of up to 50 kv, seriously affect the workshop of telecommunications equipment, microelectronics devices, computer, etc to work properly, even discharge causes the damage of the equipment, great harm to the safe production. 三、静电危害的形成条件Third, the forming conditions of electrostatic hazard 静电危害的形成应具备三个基本条件：The formation of electrostatic hazards should meet three basic conditions: 第一，产生并积累足够的静电荷，形成“危险静电源”，以至局部电场强度达到或超过周围介质的击穿场强，发生静电放电。First, generate and accumulate static charge enough, form a dangerous power, so that the local electric field intensity at or above the surrounding dielectric breakdown voltage, static discharge. 第二，在危险静电源存在的场所，有易燃易爆气体混合物存在，并达到爆炸极限浓度，或有电火物品、火炸药之类的危险品，或有静电敏感器件及电子装置等静电易爆易损物。泰安物流Second, static power there is in da