Regarding static electricity bonding
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This post was last edited by zengwenlfo on 2011-9-28 at 11:17. Many pipelines for transporting flammable liquids are glass-lined pipes and PTFE-lined pipes; how should static bonding be applied? How to prevent static electricity? Floor 13 proposed two very simple methods for controlling static electricity; I wonder how practical these two methods are Those who have already adopted these two aspects, please post a reply. Thank you. Actually, situations like the one mentioned by the original poster have been the subject of many similar discussions in this area. There are two very simple methods for controlling static electricity: 1. Controlling the flow rate to thereby control the generation of static electricity ； 2. Static electricity bonding/grounding: For pipes made of non-conductive materials such as PTFE or glass-lined steel, simply performing static electricity bonding at the external flanges certainly will not achieve the effect of dissipating static electricity. In such cases, exposed metal wires (usually copper wires) should be used to make connections inside the pipes and equipment, thereby eliminating the static electricity generated by the flow of materials within the pipes.
Can glass tubes conduct electricity too? ? It can only go into the tank, I’ve never seen it before; please help
Reply to 2# wps198682: Liner glass cannot conduct static electricity, but it can generate static electricity. How can this static electricity be removed? Is there any good solution? Question!
In my opinion, the only way is to reduce the flow rate of the liquid, in order to generate less or no static electricity! Another solution is to bridge across both ends of the glass tube or ground it separately! This is purely my personal opinion for reference only~
Reply to 4# aymzj: 1. The generation of static electricity can be reduced by controlling the flow rate; it is best to keep the flow rate below 3 M/S, but this cannot eliminate static electricity entirely. But too slow a flow rate will affect production. 2. Enameled steel is non-conductive in itself; connecting its ends together or grounding it directly has no effect – it’s a bit like trying to silence the noise by covering one’s ears. Please advise, experts
Within the pipeline, only the flow rate can be controlled; external flanges are used for bridging, and it is advisable to use a nitrogen sealing device in the receiving container. If a tank is used for reception, nitrogen should be introduced before material is added or before stirring starts. Given the three elements required for combustion – fuel, oxidizer, and an ignition source – here the combustible liquid represents the fuel, while static electricity is generated during the flow of liquids, acting as the ignition source. Therefore, only the oxidizer can be controlled by introducing nitrogen to keep the oxygen concentration below 14%.
For pipes that require electrostatic grounding, good electrical conductivity must exist between various sections; when the resistance between each pair of flanges or threaded connections exceeds 0.03 ohms, a wire bridge should be installed. In fact, for pipes that have just been installed, the resistance between the flanges or threaded connections is less than 0.03 ohms. However, once the piping system starts operating, chemical and electrochemical reactions cause the resistance between the flanges or threaded connections to exceed 0.03 ohms; in such cases, it is necessary to use wires for bridging. So, using the flange bolts of ceramic pipes for cross-wire connections can eliminate static electricity. Regarding the issue of static electricity accumulation, it is necessary to combine it with static electricity bonding and grounding measures.
Reply to 6# Taosheng Yizhou8228: That makes sense; controlling catalysts to reduce accidents is one method. But I think it’s not very practical, because the oxidizing agent is oxygen in the air, and it’s too difficult to control. Just as keeping valuables safe is one way to reduce theft, controlling the thieves is the best solution. I still want to start by controlling the ignition source. Please advise, experts
Reply to 7# jzs6699: You may have misunderstood. Using an electrostatic jumper can dissipate the static electricity from the flange, but the glass-lined pipe itself does not conduct static electricity. Just like a wire: no matter how long you connect it, if there’s a break somewhere in the middle, it won’t conduct electricity. Please advise me
Do you have an email address? You can contact me and I’ll help you solve it. huangbin-2002@126.com.
This post was last edited by yzkingsoft on 2011-9-25 at 15:56. It is estimated that what the original poster is referring to is an enamel-lined reactor combined with pipes lined with plastic or Teflon; in such cases, only the flow rate and nitrogen protection can be controlled, though bonding is still necessary. As for nitrogen, the nitrogen supply from the utility system is always on; what else can be done?