Are anti-static treatments necessary and possible for fiberglass-reinforced plastic or steel-lined storage tanks?

I’ve checked for you: Fiberglass anti-static oil storage tanks can be used. The design involves a fiberglass tank body along with material inlets and outlets located at the upper part of the tank, thus forming an anti-static oil storage tank. The structural layers of the tank body, from outside to inside, are as follows: an outer wall with multiple reinforcement rings, a fiberglass structural layer, an anti-corrosion lining layer, an anti-static layer, and inner wall support rings. The anti-static layer is made up of conductive metal mesh or anti-static coating films, and it is connected to the flanges of the material inlets and outlets that are grounded

In fact, the same problem exists with glass-lined reaction vessels as well: how to prevent static electricity inside the vessel, and what methods are both economical and practical?

Anti-static treatment for fiberglass: Attach a PVC pipe to the wall of the cylinder (a diameter of around 25–30 mm is sufficient), with the adhesive layer thickness kept at no more than 5 mm； In actual use, only one conductive tube needs to be inserted (the conductive tube can be made of rebar or thin steel bars), and this conductive tube must make contact with the ground ； For PE anti-electricity intrusion treatment, just like with fiberglass reinforced plastic, it is sufficient to directly weld the PE round tubes

I would like to ask whether this material reacts with graphite (or carbon rods). Also, is the pressure inside the equipment positive or negative? If there is no reaction, the following method can be used; it does not require positive pressure. Just find any flange interface, use a plastic flange, weld one end of the graphite electrode (or conductive carbon rod) to it, ground it on the outside, and extend it slightly on the inside. Of course, you can also find some kind of connection at the bottom as well. This method is quite effective; we use it in the exhaust pipes of our polypropylene products (using the black carbon rods found in batteries). Graphite is not expensive (note: before using it, make sure that what you’ve purchased is conductive; some are treated with a coating on their surface, which makes them non-conductive)

Hello, I’ve thought about it. Since your materials can be stored using 304 stainless steel, you can simply use 304 stainless steel pipes and flanges to create a pipe that is inserted at the bottom of the storage tank; the other end of this pipe can then be grounded. As for the rest, I don’t think it’s necessary for me to explain it to you – it works whether there is positive pressure, negative pressure, or normal pressure

A reminder for those on the 6th floor: static grounding cannot be considered effective just because you say it is; there are specific standards for measuring static resistance. The \"SH 3097-2000 Standards for Design of Static Grounding in Petrochemical Industries\" stipulates the following: Appendix A – Methods for Testing Static Grounding. A.0.1 Testing of static grounding should be carried out when the object being tested is not charged. The objects under test include the grounding system in equipment, non-metallic materials, anti-static products, etc. A.0.2 The measurement of equipment grounding shall comply with the following provisions: 1 The contact resistance and bridging resistance between the metal components of the equipment, as well as between the equipment and the dedicated grounding electrodes, can be measured using a regular multimeter; 2 The resistance of the equipment’s grounding electrodes, including the contact resistance between the grounding electrodes and the soil, as well as the resistivity of the soil, can be measured using a ZC series ground resistance tester. The distance between the ground electrode and the current electrode should be 40 m, while the distance between the voltage electrode and the current electrode should be 20 m. The resistance measurement requirements for non-metallic components in these devices (such as non-metallic parts used for grounding, insulating flanges, etc.) are as follows: when the resistance is less than 1 MΩ, it can be measured using a regular multimeter or a high-impedance meter; when the resistance is 1 MΩ or higher, a high-impedance meter or megohmmeter with a voltage rating of 500 V or more should be used for measurement. A.0.3 The measurement of the electrical conductivity of non-metallic materials shall comply with the following provisions: 1 For sheets, films, etc., the volume resistivity and surface resistivity – when the volume resistivity is greater than or equal to 10^6 Ω·m, the measurements shall be carried out in accordance with the \"Test methods for electrical insulation resistance, volume resistivity, and surface resistivity of solid materials\" GB 1410-78; instruments such as ZC36 and ZC43, which are high-resistance meters, can be used for these measurements. Sample size: square, 100 × 100 mm, or circular with a diameter of 100 mm. When the volume resistivity is less than 10^6 Ω·m, measurement is carried out in accordance with the standard \"Methods for Determining the Resistivity (Coefficient) of Conductive and Antistatic Rubbers\" GB2439-81; the input impedance of the electrometer and ammeter must be greater than 10^252 Ω. Sample size: length 70–150 mm, width 10–150 mm. The fiber leakage resistance is measured in accordance with the standard \"Methods for Testing Fiber Leakage Resistance\" FJ551-85, with a sample quantity of 2 ±. 1g. The testing instrument is a fiber leakage resistance tester based on the RC charging and discharging principle. 3 The conductivity of light petroleum products is measured in accordance with the method specified in GB6539-86, \"Method for Determining the Conductivity of Light Petroleum Products\". The sample oil volume is greater than 1 L, and the measuring instrument used is an oil conductivity tester. A.0.4 The measurement of the electrical conductivity of anti-static products shall comply with the following provisions: 1 The resistance of anti-static shoes and conductive shoes shall be measured in accordance with the \"Method for Measuring the Resistance Values of Anti-static Soled Shoes and Conductive Soled Shoes\" GB4386-84. When R -> 1.5 X 10^5, the measured voltage is 500 ± 125 V; when R < 1.5 X 10^552, the measured voltage is 100 ± 5 V, with the test power not exceeding 3 W. The resistance of floor coverings such as floors and carpets is measured using two special electrodes of size 06 012 mm (weight: 210.2 kg, made of brass plated with chromium). The distance between the measuring electrodes is 1 m. For non-flexible surfaces, a conductive sponge (diameter: 60 mm, thickness: 5–6 mm, volume resistivity: 0.1–162 Ω·m) can be placed under the electrodes. An insulation resistance tester with a DC open-circuit voltage of 500 V and a short-circuit current of 5 mA can be used for measurements. SH 3097-2000 Appendix B: Precautions for Static Grounding Operations. B.0.1 In areas where static electricity may pose a hazard, the static grounding of mobile equipment and tools should be carried out according to the following procedures: 1 Grounding must be completed before any processing or transportation takes place. 2 After the process operation or transportation is completed, and after the specified settling time has passed, the grounding wire may be removed. 3 The location of the grounding wire connection points should be kept away from areas at risk of fire or explosion, and it should not be in the downwind direction of the loading and unloading areas. B. 0.2 During the production process, when local maintenance of equipment, pipelines, etc. causes the static electricity connection circuit of relevant components to be interrupted, temporary bypass connections should be established; these connections must be removed again after the maintenance is completed, and the resistance value should be measured once more. Day 0.3 Grounding equipment and materials should be used properly, and regular inspections should be carried out to ensure the integrity of the electrical connections. If there is a break in the grounding connection, measures should be taken to ensure that the surrounding area is free from the risk of explosion or fire before the connection is restored. B.0.4 Metal tools used for sampling, measuring length, and taking temperature of flammable and explosive materials must not come into contact with metal vessel walls during operation

Perhaps the method I mentioned won’t work for you, but it can serve as a reference. Of course, you can try it out as well; however, if it’s used for testing on equipment, it certainly won’t meet the requirements (since the equipment itself doesn’t conduct electricity). But you can connect an electrostatic discharge indicator in series with the grounding wire – this device allows you to clearly see that static electricity is being discharged. Such devices are available on the market. As for their effectiveness, nothing can be guaranteed absolutely

Choose any flange connection; use a plastic flange, weld one end of the graphite electrode (or conductive carbon rod) to it, ground the outside part, and extend the inside part slightly. That’s exactly what we do. There is no problem with measuring resistance.

Static electricity can also be discharged using titanium tubes, as titanium is resistant to corrosion and has good electrical conductivity. Fix it from the top with a flange. Simply connect the titanium tube to the electrostatic ground electrode.

For steel-lined storage tanks, I believe it is not necessary to carry out special anti-static treatment; it is sufficient to ensure that the tanks have adequate anti-static properties.