The harm of static electricity to chemical production and preventive measures
There are three hazards of static electricity.
1. Explosion and fire. Explosion and fire are the biggest hazards of static electricity. Although the energy of static electricity is not large, because of its high voltage and easy discharge, static sparks appear. In flammable and explosive places, static sparks may cause fire or explosion.
2. electric shock. Electric shock caused by static electricity may occur when the human body is close to a charged object, or when the human body with electrostatic charge is close to the grounded body. Under normal circumstances, the energy of static electricity is small, so the static electricity shock in the production process will not directly make people fatal, but because of the electric shock, it is easy to cause secondary accidents such as falling and falling. Electric shocks can also cause stress and affect work.
3. affect production. In some production processes, failure to eliminate static electricity will affect production or reduce product quality. In addition, static electricity can also cause electronic components to malfunction and cause secondary accidents.
3. Measures to prevent static electricity
1. Process control method
The process control method is to take measures from the aspects of process combing, equipment structure, material selection and operation management to limit the generation of current or control the accumulation of static electricity, so that it is controlled within a safe range. The main measures are:
①Limit the conveying speed;
② Correctly distinguish between static electricity generation area and dissipation area, and take different anti-static measures;
③Select appropriate materials for equipment and pipes
④ Arrange the material input sequence appropriately;
⑤ Eliminate additional sources of static electricity.
2. Leak away method
The leakage conduction method is the electrostatic grounding method. Static grounding is a simple and effective way to eliminate static electricity on conductors, and is the most basic measure to prevent static electricity. The process can be used to humidify the air and add antistatic agents. The electrostatic grounding connection is an important part of the grounding measures. Methods such as electrostatic jumper, direct grounding, and indirect grounding can be adopted to connect each part of the equipment to the earth through the grounding electrode. The resistance of the electrostatic connection system should not be greater than 100 ohms.
3. Electrostatic neutralization
The electrostatic neutralization method mainly ionizes molecules to generate ions necessary to eliminate static electricity (generally positive and negative ions are paired). Among them, the ions with the opposite polarity to the charged object move to the charged object and neutralize the charge of the charged object, so as to achieve the purpose of eliminating static electricity. This method has been widely used in the production of film, paper, cloth and other industries, but improper application or error will weaken the effect of eliminating static electricity, and even cause accidents. This principle is used to make static eliminators. The main types of static eliminators include self-induction, external power supply, radiation, ion flow, and combined types; in production, the appropriate static eliminator is selected according to production needs.
4. Anti-static measures for the human body
In addition to causing electric shocks to the human body and threats to safe production, live humans can also cause quality accidents during the production of precision instruments or electronic components. Therefore, it is necessary to address the hazards of live humans to industrial production. The measures to eliminate static electricity on the human body are:
① The human body is grounded. In places where the human body is grounded, a metal grounding rod should be installed. The staff can touch the grounding rod with their hands at any time to eliminate the static electricity of the human body. In sitting workplaces, workers can wear a grounded wrist strap. There should be exposed metal grounding objects at the entrance and outside of the anti-static place. Be aware of benzene in places with static electricity hazards. Workers should wear anti-static clothes, shoes and gloves, and no chemical fiber clothing. The purpose of wearing anti-static shoes is to ground the human body.
Field work ground is conductive. The working ground of the special dangerous place should be conductive or cause the conductive strip; the resistance value of the leakage resistance of the working ground should be small enough to prevent the human body from accumulating static electricity, but also to prevent the human body from being harmed by electric shock, so the resistance value should be Appropriate, generally 3x10^6 ohm≤R≤10^6 ohm.
③Safe operation. a. Try not to engage in activities that can make people electrify at work; b. Use prescribed protective equipment reasonably; c. Work in an orderly manner and avoid acute actions; d. Do not carry metals that are not related to work in an anti-static place Articles; e. Mops or rags made of chemical fiber materials are not allowed to clean articles and the floor.
The safety production managers of chemical companies should pay attention to the hazards of static electricity in chemical production i. Eliminate the hazards of static electricity through reasonable safety measures, so as to ensure the safe production of the company and avoid accidents.