EA003411B1 - Device for static electricity elimination used during racking, transportation and loading/unloading of inflammable or explosive materials - Google Patents

Abstract

1. The device for the elimination of static electricity which is used at the racking, transportation and unloading inflammable and explosive materials by means of energy balancing in points with different energy cumulative levels characterized by the sealed in the cage (11) energy chip (22) of the device, having first energy branch point (1), connected by cable (44) ending in crocodile clamp (33) with the object (12) and the second point (8) connected to the cage (11) and, by second cable (55), to the ground coupled plate grounding (78) wherein the circuit (22) contains between first (1) and second (8) points concatenated diode (D1), first resistor (R2), second diode(D2) and second resistor (R3), connected in parallel to first condenser (C4), this circuit contains also concatenated second (C2) and third (C3) condensers connected in parallel to first resistor (R2), common point (3) their connections is connected through the third resistor (R1) is connected with point (7) of connection of second diode (D2) and second resistor (R3), and is connected with first point (1) of circuit (22) through connected in parallel fourth condenser (C1) and glittering diode (T1). 2. The device, according to claim 1, is characterized by the cage of the device (11), placed on the tin plate (99) connected by bolts on column (77) ending in three welded branches (100) which have been placed together with a part of the column (77) into a concrete pedestal (88), having on the column (77) on one side welded crotches (121) serving for the storage of cable (44) and on the other side a branch positioned by means of bolts serving for the connection of the cable (55) with the ground-coupled plate grounding (78).

Description

FIELD OF THE INVENTION

The present invention relates to devices for eliminating electrostatic charge and, in accordance with the International Patent Classification (IPC), can be assigned to classes B 65 Ό 90/46 and H 05 R.

Technical problem

During the movement (loading / unloading) and transportation of oil and oil products, combustible gases and liquids, explosive materials (gloves) or solid combustible materials carried out at loading terminals for vehicles, shipyards with loading terminals for tankers, moving tractors or trailers, as well as other similar means, cars and similar vehicles, the problem arises of eliminating the electrostatic charge, which is formed during the implementation of the above techno logical operations.

Until such a problem is solved, there is a latent danger of fire, explosion, disruption of the process, as well as the effects of the accumulated charge on bio and electrostatic fields (which leads to a violation of the psychophysical conditions of working specialists).

Using the proposed rather simple technical solution described in this application, which is simple and reliable during installation, operation and storage, the above-mentioned hidden dangers caused by static electricity can be avoided.

State of the art

Known from the prior art solutions for eliminating the charge of static electricity during the aforementioned technological operations indicated in the title of this invention are:

- direct grounding of the selected object;

- grounding with a single-pole camshaft of the object (capacity) under consideration;

- grounding using a grounding detector of the object (capacity) under consideration;

- antistatic tape (conductive tape - for electrical connection of the object in question with the Earth) on tractors and trailers.

In general, all existing technical solutions can be reduced to the principle of grounding. Technical solutions using the grounding principle are described in a review of the current state of the art, including the following patent and non-patent literature.

Patent Literature:

I8 4,345,297; ϋ δ 4,319,303; ϋ δ 3,893,004; I8 3,895,260; ϋ δ 3,896,340; 8I 1535780 A1; ϋδ

3,893,003; CH 653 643 A5; P-1302/75 (Applicant: Texas Esus1ortsp1 SotrotaNoy, USA).

Non-Patent Literature:

(a) Elimination of electrostatic problems in the oil refining industry, 1oitia1 o £ E1ec1to81aBc8, Uo1. 27 (1992) N. N. ^ a1tz1eu.

(b) XV. M. Vi81sh & XV. S. Oikek Electrostatics in the Oil Refining Industry, δоίййатрΐоη, 1983.

(c) 1o8eG M. Sgo \\ '1eu Fundamentals of applied electrostatics, Youe Wagk, 1986.

(d) Τδ. M1118 & KS. O1y11at Evaluation and prevention of electrostatic problems in operations with oil tankers, Oete Wogk, 1983.

(e) Scientific and technical project Study of the phenomenon of static electricity under conditions of operation, processing, transportation, discharge and storage of oil and oil products using the example of oil refining, Energoinvest, δΙΖ soldering В1Н, Faculty of Electronics, Bosansky Brod, Sarajevo, 1987.

(f) Scientific-technical project UKYOδδΝΟ-δΡΚΙ, Belgrade and the Faculty of Electronics, Sarajevo, Sarajevo-Belgrade, 1981.

All these solutions have many disadvantages, which can be reduced to the fact that they do not completely eliminate the electrostatic charge and, thus, create a risk of disruption of the working and technological process, as well as the everyday life danger in the course of the described technological processes.

The result of these shortcomings is a latent hazard caused by static electricity, which manifests itself in fires and explosions, which also leads to disruption of technological processes and the effect of the accumulated charge on the bio and electrostatic fields of working specialists.

Existing technical solutions for eliminating and discharging static electricity are reduced to one solution, namely, to grounding in various ways. Thus, it was concluded that it is sufficient and necessary to ground the aforementioned containers used in technological processes during the movement (loading / unloading) and transportation of oil and oil products, combustible gases and liquids, explosive materials (explosives) or solid combustible materials , and thus discharge and eliminate electrostatic charge.

The appearance of an electrostatic charge is a natural process, i.e. stochastic process as a result of technological progress, and everyday life and, therefore, it is necessary to discuss and develop a concept for solving an existing problem as a result of its analysis and study. Static electricity, in essence, is the result of the interaction of two layers (in other words, the result of friction).

Each technological process or action is characterized by certain parameters and possible results. The mentioned technological process or the result of the indicated technological operations (as indicated in the title of the invention) is characterized by the presence of concentrations of explosive components. These components can be ignited by a spark with minimal ignition energy. If the grounding of the containers under consideration is provided, then it will instantly equalize the energy by means of a discharge between the points of accumulated electrostatic energy, which are distributed throughout the body of the tank in question (in this case, it is a fuel vehicle) and the Earth (grounding system as a reference point). Earth as a configuration or body has the highest energy level in relation to all other bodies (capacities) located and working on Earth.

This leads to an unexpected discharge of accumulated energy (by means of a discharge pulse or spark) between the mentioned points of the accumulated electrostatic charge energy of a certain sign, so that we can assume that the object in question is isolated and aligned with another system. If at the object under consideration (during the process under discussion - operations) the technological operations under consideration are carried out, and if the object under consideration is treated as an isolated electrostatic system, then you can try to forcibly connect it to some other given electrostatic system (in a particular case, it is a fuel vehicle, directly connected to the earthed grounding plate by means of a tape) and this will cause forced alignment of the accumulator electrostatic energy between these points.

As a result, the process operation under consideration is potentially dangerous, manifested in the ignition of an explosive mixture (in this case, oil and oil products combine with air to form explosive mixture concentrations), which leads to fire and explosion.

The question arises of what happens if the tank in question (oil tank) remains permanently grounded, and what this may lead to.

The electrostatic system under consideration will be characterized by the presence of points of accumulated electrostatic energy, and will be a no longer isolated and aligned system, but it will necessitate electrostatic alignment between the points of accumulated electrostatic energy located inside and on the surface of the container under consideration. This will accelerate the creation of conditions for the discharge of accumulated energy (pulsed or spark discharge), which has essentially the minimum ignition energy needed to ignite an explosive mixture. In fact, this creates a latent potential threat caused by static electricity during the process and leading to fires and explosions.

Thus, grounding is a special case of eliminating static electricity, but cannot serve as the main measure of eliminating static electricity, especially during the technological processes or operations that are discussed here, namely during the movement (loading / unloading) and transportation of oil and petroleum products, combustible gases and liquids, explosive materials (explosives) or solid combustible materials, as they can cause a fire and explosion. There is no need to discuss the discharge of static electricity into the Earth.

The aim of the present invention is to provide a device for eliminating electrostatic charge without an external power source, which creates an energy balance between the mentioned points of the accumulated electrostatic energy (on the oil tank and the Earth where the grounded plate is located) so as not to discharge the accumulated energy through a pulse or spark ( as mentioned above, a pulsed or spark discharge with an energy sufficient to ignite the concentration of the explosive mixture).

Description of the invention

The device for eliminating the electrostatic charge, according to this invention, contains a casing in which an energy module is enclosed, a tinned plate for securing the casing, a stand on which the casing with the circuit is placed on one side, and three supports that are located in the ground on the other side, two cable, one of which is used to connect the device to the tank in question (oil tank), and the other is used to connect this device to a grounded plate, crocodile clamps, which are used to connect neniya cables considered container (object), a chain for connecting said device with a grounded plate and fork for winding the cable with the clamps (winding of the cable may also be carried out by automatic Unreelers). The device can also be installed without a stand, if this is caused by circumstances of a technological or operational nature.

The principle of operation of this device is to equalize the energy between these points, the accumulated electrostatic charge of the tank in question (for example, an oil tank) and ground with the Earth, without using an external power source during its operation, and thus it belongs to the group of passive devices . The power of this device is provided by available sources of accumulated electrostatic energy at the points of the two electrostatic systems under consideration. The device is easy to manage, operate and store.

A device for eliminating electrostatic discharge is shown in the drawings below.

Brief Description of the Drawings

FIG. 1 is a general schematic view of a device; FIG. 2 - electrical circuit of the circuit;

FIG. 3 - a method of mounting the device to a fuel vehicle.

DETAILED DESCRIPTION OF THE INVENTION

In FIG. 1 schematically shows a device containing the following elements: a casing (11) having a shape corresponding to the operating conditions for each individual purpose, in which on a special mounting panel, bolted inside the casing, is placed a circuit (22), a tinned plate (99), fixed bolts on the column (77), which holds the tinned plate and the casing, the first cable (44) that ends with a crocodile clip (33), the second cable (55) connecting this device to the block (66), which is bolted to the column ( 77) together with for emlennoy plate (78).

A plug (121) is welded to the column (77), which serves to wind and store the first cable (44) after the end of the process of eliminating the electrostatic charge. At the end of the column (77), three supports (100) are welded, which serve to fix the column (77) in a concrete support (88).

In FIG. 2 shows a detailed electrical diagram of the circuit (22), which is hermetically mounted in the housing (23), specially made for installation and use in possible explosive areas. The housing (23) is specially made, processed and filled with a special mass and then placed on a special board, bolted inside the casing (11). The casing (11) is made with the possibility of gluing it with the housing plate (23). The circuit has two external connection points, the first 1 of which is connected with crocodile clips (33) and the first cable (44) to the object (12), the electrostatic energy of which must be equalized, and the second point 8 is connected to the specified casing (11) and by means of a second cable (55) with a grounded plate (78). Point 9 is the connection point of the casing (11) with the second external connection point 8.

The grounded plate (78) is taken as a reference point and does not always have to be depicted, as shown in FIG. 2 (grounding), and another point of reference can be selected another point of accumulation of electrostatic energy.

The specified circuit contains in the first circuit between the indicated first 1 and second 8 external connection points a series of elements, including the first diode Ό1, the first resistor K2, the second diode Ό2 connected at the first point 7 of the joint connection with the second resistor K.3 and the first capacitor connected in parallel C4. The specified circuit also contains a number of elements, including the second C2 and the third C3 capacitors forming the second point 3 of the joint connection. In addition, the circuit includes a parallel connection of the fourth capacitor C1 and a gas discharge neon lamp T1 connected between the first external point 1 and the second point 3 of the joint connection. The circuit also includes a third resistor K1 connected between said first 7 and second 3 points of joint connection.

Elements located between points 4, 6 and 3, i.e. capacitors C2, C3 and resistor K2 are elements of the exchange circuit between the energy levels of the generated electrostatic energy.

In FIG. 3 shows a method of connecting the device (11) with an oil tank (12). It should be noted here that the connection method is the same for all types of containers. In addition, instead of insulated crocodile clips, it is possible to use insulated clips of a different type.

A device for eliminating electrostatic charge is used when moving (loading / unloading) and transporting oil and oil products, combustible gases, fuels and similar materials (as defined in the title of the invention), and its work is based on equalizing energy potentials between the points of accumulated electrostatic energy, determined time constants of the electric field (ohmic and capacitive resistance) so that there is no discharge (discharge pulse or spark) of the electrostatic charge.

There are two separate systems of electrostatic energy (which are characterized by points of accumulated electrostatic energy), whose energy levels must be equalized, one of which is the surface of the Earth, where a grounded ground plate is placed (78), and the other is a direct oil tank whose electrostatic energy must be equalized with the first system (since it is always

Ί invariably has a higher energy potential).

As a reference point for equalizing the energy between the points of the accumulated electrostatic energy of these two systems, the point of the grounded plate (78) was chosen.

By controlling the equalization of the energy levels of these two systems, the possibility of a pulsed discharge is eliminated not only on the surface, but also inside the tank under consideration (in the particular case of an oil tank), which is essential and necessary to achieve this.

In this case, the refueling oil tank (or other tank under consideration) is the first energy chain for the energy equalization of electrostatic charges, the constituent elements of which are indicated respectively (33), (44), C1, T1, C2, Ό1, and the grounded plate is another energy circuit for electrical alignment, the constituent elements of which are indicated respectively (78), (55), K.3, C4, Ό2, K1, C3. A circuit with elements C2, C3, and K.2 connected between points 3, 4, and 6 is a circuit for exchanging between the energy levels of the accumulated electrostatic energy of the first and second circuits (two energy systems and the systems described above).

By determining the time constants for the ohmic and capacitive resistance of the electrostatic discharge, the values of the capacitors C1, C2, C3 and C4, resistors K1, K2, K3 and diodes Ό1 and Ό2, as well as a gas discharge neon lamp T1 (which serves to determine the critical breakdown voltage or energy, are selected light discharge in the case under consideration).

The exchange of energy levels between the points of accumulated electrostatic energy of the two aforementioned systems occurs by means of a light discharge determined by a time constant and does not constitute a danger to the considered technological operations (indicated in the title of the invention). The duration of the exchange of electrostatic energy between the two energy levels of the two systems described above until they are equalized is determined by the time constants for the ohmic and capacitive resistance, calculated and determined in the manner described above.

The circuit diagram, which performs the function of eliminating the electrostatic charge by the method of exchanging energy between energy levels (equalization method) between the points of accumulated electrostatic energy of the two aforementioned uninsulated systems, consists of the elements shown in FIG. 2. The selection of these elements depends on the type of material selected, characterized by ohmic, surface and capacitive resistance.

The number of energy exchange cycles between the energy levels of the considered points of the accumulated electrostatic energy also depends on the type of hazardous substance under consideration.

Each hazardous substance is characterized by ohmic, surface, and capacitive resistance, and on this basis it is possible to determine the time coordinates (the attenuation time caused by the contact of the double layer) and, knowing the value of the time constant, it is possible to calculate and select the electrical components that will ensure the operation of the circuit.

You can also select the electrical components of the circuit, the type, length and configuration of the extension cord with the connector and the cable reserve (44) and (55) on the oil transport tank (12) and the grounded plate (78), working on the principle of energy exchange between the points of accumulated electrostatic energy .

Since the appearance of static electricity is the result of a double layer contact, i.e. of a natural process, it was found that the plus + or minus - sign preceding the charge at the point of accumulated electrostatic energy (oil tank (12)) can be changed per unit time (this also applies to a grounded plate (78)).

Thus, to describe the operation of the circuit (22), as well as the device as a whole, according to this invention, it is necessary to consider all possible combinations of signs preceding the charge at the point of accumulated electrostatic energy. In a particular case, a possible combination was determined: on the oil tank (12), the signs of charges were as follows: + - + -, and the potential on the grounded plate (78) relative to the previous signs was as follows: - + + -.

In this description, we consider the case when the sign preceding the charge at the points of accumulated electrostatic energy on the oil tank (12) is +, and the sign on the grounded plate is also +. The equalizing current flows from the oil tank (12) through the clamp (33), cable (44), point 5, diode Ό1, point 4, capacitor C2, point 3, resistor K1, point 7, capacitor C4, cable (55) leading to the grounded plate (78), and over time it will be zero. During this process, the equalization current flows, the capacitors C1, C2 and C4 will charge.

On the other hand, because the charge sign at the points of accumulated electrostatic energy of the grounded ground plate (78) has a + sign, the equalization current flows through the resistor K3, point 7, diode Ό2, point 6, capacitor C3, point 1, cable (44) and clamp (33) like a crocodile to a tank (12), and also over time 1 will be zero.

In addition, during the flow of the equalization current, the capacitors C3 and C1 will charge. All this happens in a relatively short period of time without discharge of the accumulated charge.

Electrostatic energy is compensated by capacitors and, therefore, capacitor C1 transfers its electrostatic energy to a T1 gas discharge neon lamp, and capacitors C2 and C3 mutually transmit electrostatic energy to each other through resistor K2 (by correctly selecting the values of C2 and C3 as a function of the number of energy exchange cycles among energy levels the accumulated electrostatic energy in question, which in turn depends on the type of hazardous material in question). The working area of the circuit (22), as well as the entire device is in the range of capacitance.

All other described cases with charge signs of the considered points of the accumulated electrostatic energy are considered in the same way and can be investigated in a pulsed or some other mode.

Any analysis comes down to the fact that the solution allows you to avoid and prevent discharge (discharge pulse or spark), which is the purpose of this device. This goal is achieved by this device, which has the advantage that it is driven without an external power source, which is very important for its use in areas of high fire and explosion hazard.

The technical solution of the described device, according to the present invention, is based on a completely new approach to the elimination of electrostatic charge (as described in this application). Unlike the solutions known from the prior art, this device does not direct the discharge current to the Earth, but only aligns the energy levels between the points of the accumulated electrostatic energy in two systems. The proposed device is a new technical solution in the field of devices of this type and provides complete safety and reliability of the above technological operations in the conditions of dangers caused by static electricity. This device has been tested and studied under real operating conditions, and was monitored during the transportation, loading / unloading of 816 potentially hazardous materials. For each of the above materials, it is necessary to conduct an appropriate selection of the values of the electrical components in the energy module, depending on the electrical properties of the material used (ohmic, surface and capacitive resistance).

Claims (2)

1. Device for eliminating electrostatic charge during loading, transportation and unloading of combustible and explosive materials by balancing energy at points with different accumulated levels of electrostatic charge, containing a circuit (22) hermetically placed in the casing (11), having a first point (1) connected by means of a cable (44) and a clamp (33) with an object (12), and a second point (8) connected to the casing (11) and by means of a second cable (55) with a grounded plate (78), while the circuit of the specified circuit (22 ) between the first (1) and second (8) points it contains in series the first diode (Ό1), the first resistor (K.2), the second diode (и2) and the second resistor (K3), in parallel with which the first capacitor (C4) is connected, this circuit also contains a second (C2) and third connected in series (C3) capacitors connected in parallel to the first resistor (K2), the common point (3) of which is connected through the third resistor (K 1) to the connection point (7) of the second diode (02) and the second resistor (K3), and through parallel connected a fourth capacitor (C1) and a gas discharge neon lamp (T1) are connected the first point (1) circuit (22). 2. The device according to claim 1, characterized in that the casing (11) is mounted on a tinned plate (99), which is bolted to the column (77), at the end of which three supports (100) are welded, which together with the end part of the column (77) is placed in a concrete stand (88), and on one side of the specified column (77) a plug (121) is welded, which serves to accommodate the first cable (44), and on the other side of the specified column, a block (66) is fixed by bolts serving to connect the second cable (55) to a grounded plate (78).