RU117298U1 - INSTALLING UNDERSTANDING FIRE EXTINGUISHING IN RESERVOIRS WITH OIL PRODUCTS - Google Patents

Abstract

1. Installation of sub-layer fire extinguishing in the tank, including the mortar pipeline connected in the technological sequence, equipped with an electric valve, foam pipelines equipped with high-pressure foam generators, check valves, bursting membranes, while the foam pipelines inside the tank are rigidly connected to stationary support pipes equipped with internal wiring with foam nozzles, which is different the fact that the foam nozzles are located in pairs in vertical planes at a height of 2/3 of the filling level of the tank, while the stationary support pipes are fixed to the walls of the tank. ! 2. An installation according to claim 1, characterized in that the pairs of foam nozzles are located opposite to each other with respect to a vertical plane passing through the center of the tank and perpendicular to the plane of the stationary support pipes.

Description

The inventive utility model relates to fire fighting equipment, in particular, to foam installations for sub-layer fire extinguishing of oil products in steel vertical tanks for long-term storage of oil and oil products.

Sublayer fire extinguishing installations in tanks are known, in the general case including distribution pipelines with foam nozzles located on distribution pipelines, which, in turn, are fixed to a floating plate or foam nozzles that are “rigidly” placed on distribution pipelines at a level of 90- 95% tank filling (at the top of the tank).

Thus, the installation of sublayer extinguishing for oil and high viscosity oil products is known, including a foam pipe equipped with an electromagnetic valve and a valve connected to a foam generator. Inside the tank, the foam conduit is “rigidly” connected to a support pipe led out from the bottom of the tank, into which a movable pipe is sealed, mounted on a floating plate and equipped with wiring with a non-return valve and foam nozzles (RF patent for utility model No. 99716).

The main disadvantages of this device are:

1. The proximity of the two foam nozzles to the center of the tank, which leads to uneven spreading of foam on the surface of the fuel from the center to the edge.

2. The presence of a set of pipes (support and retractable pipes), which may lose mobility as a result of operation, as it is assumed, long-term storage of petroleum products.

3. The constant location of the foam nozzles in the upper level of filling the tank with oil products, since the plate constantly floats on the surface of the fuel and moves vertically when the height of the fuel is changed, which will lead to mild mixing of the “cold” layers of fuel with a heated homothermal layer during the extinguishing process .

4. The need to change the design of the tank due to the output from the bottom of the support pipe.

Also known is the installation of sublayer quenching of oil and oil products in reservoirs containing water, including a foam pipe with a valve and a foam generator. An additional vertically oriented set of elbows of retractable pipes of various diameters is installed on the foam pipe inside the tank, the upper pipe of which is fixed to a plate floating on the surface of the oil product and is equipped with wiring with a non-return valve and foam nozzles (RF patent for utility model No. 844544).

The main disadvantages of this device are:

1. The proximity of the two foam nozzles to the center of the tank, which leads to uneven spreading of foam on the surface of the fuel from the center to the edge.

2. The presence of a set of elbows of retractable pipes that can lose mobility during operation.

3. The constant location of the foam nozzles in the upper level of filling the tank with oil products, since the plate constantly floats on the surface of the fuel and moves vertically when the height of the fuel is changed, which will lead to mild mixing of the “cold” layers of fuel with a heated homothermal layer during the extinguishing process .

The closest in technical essence to the claimed utility model is the installation of a sublayer extinguishing of long-term storage tanks for oil products, including a foam pipe equipped with valves, a check valve, an electromagnetic valve, equipped with a manual opening and closing device, a communication line and a starting device. The foam pipe inside the tank is rigidly connected to the stationary support pipe, which is connected to the roof and bottom of the tank and is equipped with a wiring with a non-return valve and two foam nozzles installed in the upper part of the tank at a height of 90% of its filling (RF patent utility model No. 107947).

The main disadvantages of this device are:

1. The proximity of the two foam nozzles to the center of the tank, which leads to uneven spreading of foam on the surface of the fuel from the center to the edge.

2. The location of the foam nozzles at the level of 90% filling the tank with oil products, which leads to poor mixing of the “cold” layers of fuel with a heated homothermal layer or the complete absence of mixing of the oil if the tank is filled below 90% level.

3. The presence of a stationary pipe rigidly connected to the roof of the tank, which leads to a change in the design of the tank, the presence of additional welded joints and damage to the internal wiring of the foam pipes when the vapor-gas medium explodes and the tank roof breaks or is completely destroyed.

One of the disadvantages of the prototype is the upper arrangement of the foam nozzles, in this case, the foam is fed directly into the surface layer of the oil product, the so-called "homothermal" layer. If the oil product in the tank is below the 90% filling level, the foam will be fed to the layer of the burning product from above, where it will undergo contact destruction from exposure to the flame.

In addition, the location of the two foam nozzles in a horizontal plane near the center of the tank mirror also negatively affects the performance of the device, since with this arrangement the foam will be distributed unevenly on the surface of the fuel and foam flows will reach the center of the tank mirror earlier than its walls, which will require more continuous supply of foam to cover the entire mirror of the tank with a layer of foam of a certain height. The thickness of the foam layer will also vary unevenly: in the central part of the mirror of the tank, the thickness of the foam will increase faster than at the walls of the tank, and in the case of the formation of “pockets” (when the vapor-gas mixture explodes and the walls of the tank deform) with a limited supply of foaming agent or water, lead to the absence of leakage of foam into the formed "pockets" and subsequent re-ignition of fuel vapor.

The objective of the proposed technical solution is to provide the ability to quickly extinguish a fire at long-term storage of petroleum products in tanks. The technical result achieved by using the claimed utility model consists in lowering the temperature in the surface layer due to entrainment of the lower “cold” layers of the fuel by the flow of the pop-up foam and their mixing with the homothermal layer, as well as in ensuring a quick and uniform spreading of the foam over the entire surface of the fuel.

The problem is solved in that in a sub-layer fire extinguishing installation in a tank, including a mortar connected in a technological sequence, equipped with an electric valve, foam pipes equipped with high-pressure foam generators, non-return valves, bursting membranes, while the foam pipes inside the tank are rigidly connected to stationary support pipes equipped with internal wiring with foam nozzles, according to the technical solution, foam nozzles are arranged in pairs in vertical flat at a height of 2/3 of the filling level of the tank, while the stationary support pipes are fixed to the walls of the tank. In this case, the pairs of foam nozzles are located opposite each other with respect to the vertical plane passing through the center of the tank and perpendicular to the plane of placement of the stationary support pipes.

Reducing the temperature in the surface layer is achieved due to the location of the foam nozzles at the declared level, namely at the level of 2/3 of the height of the fuel in the tank, which leads to mixing of the "cold" and homothermal layer of fuel and thereby lowering the temperature in the surface layer.

In addition, the uniform location (foamy opposite) of the foam nozzles over the area of the tank mirror also contributes to a more rapid and uniform spreading of foam over the surface of the fuel.

The inventive device is schematically illustrated by drawings, in which:

Figure 1 - shows a side view of the installation mounted in the tank;

Figure 2 - shows a top view of the installation mounted in the tank;

Figure 3 - schematically shows a section of a stationary reference pipe with internal wiring and high-pressure foam generators.

Figure 4 - schematically shows the process of entrainment of the lower layers of the fuel flow of a pop-up foam.

Figure 5 - schematically shows the process of uniform spreading of the foam on the surface of the fuel.

The positions in the drawings indicate:

1 - tank

2 - mortar,

3 - high-pressure foam generator,

4, 12 - check valve,

5 - bursting disc,

6, 13 - electric valve

7 - distribution foam,

8 - foam nozzles,

9 - fastening elements of the internal wiring with the walls of the tank,

10 - stationary vertical foam,

11 - internal distribution wiring foam.

The installation (figure 1) includes a solution pipe 2 located behind the bunding of the tank 1 (or group of tanks), connected in parallel through an electric valve 16 to two opposite branches of the sets of supply equipment. The design of the electric valves shall also ensure that they are opened manually by mechanical means. Each kit contains a high-pressure foam generator (HSV) 3 connected in a technological sequence, a check valve 4, a bursting disc package 5, an electric shutter 6, a distribution foam conduit 7, introduced into the tank. Inside the tank, the distribution foam conduit 7 is equipped with a check valve 12. The internal distribution of the distribution foam conduits with foam nozzles is mounted on stationary foam conduits 10 inside the tank at the level of 2/3 of the filling of the tank and contains two foam nozzles 8 on each distribution foam conduit, as well as internal fastening elements wiring to the walls of the tank 9.

Internal stationary foam pipes are “rigidly” attached to the tank body to prevent their deformation when filling or emptying the tank. Foam nozzles are arranged in pairs opposite each other so that through their ends you can draw an imaginary circle with a radius equal to half the radius of the tank.

The inventive installation operates as follows. When a petroleum product is ignited in a tank, a foaming agent solution from a mobile fire fighting equipment or a stationary fire pumping station is fed into a supply solution pipe 2, and an electric shutter 16 is installed, which is installed behind the bunding. In the case of the use of mobile fire fighting equipment, it is installed outside the debris, which ensures the safety of equipment and personnel.

The solution of the foaming agent is automatically (or remotely by the operator) fed through the solution pipelines inside the debris to the high-pressure foam generators 3 in which foam is formed. After HSV, the resulting foam passes through the check valves 4, ruptures the bursting safety bursts 5 and through the opened gate valves 6 enters through the distribution foam ducts into the reservoir.

Foam through the distribution foam conduits 7 enters the internal distribution distributions of the foam conduits 11. After this, the check valves 12 on the internal distribution distributions open and the foam through the foam nozzles 8 enters the oil product layer. Due to the lower density of the foam, passing through a layer of fuel, carries an unheated “cold” layer of oil product, resulting in a mixing of the layers and a decrease in the temperature of the surface layer of the oil product (figure 4). Foam comes to the surface of the burning oil, spreading evenly throughout the entire mirror of the tank. As a result of the formation of a foam layer and the cessation of access of air oxygen to the combustion zone, the fire ceases.

The application of the proposed installation will allow to extinguish fires with a limited supply of fire extinguishing agents by eliminating the “idle” use of the foam spreading over the surface of the combustible foam. This effect is achieved by a uniform arrangement of four foam nozzles in the horizontal plane of the tank. To stop burning, it is necessary that the entire plane of the mirror of the tank is covered with an insulating layer of foam of a certain thickness. With an asymmetric arrangement of the foam nozzles (see prototype) close to the center or to the walls of the tank, the necessary insulating layer of foam in the center of the mirror of the tank or at the walls of the tank is formed earlier, stopping the access of fuel vapor to the combustion zone. With further coverage of the remaining part of the tank mirror, the areas already covered with foam, on which the access of fuel vapors to the combustion zone is stopped, will receive foam “idle”, which will lead to an excessive consumption of foaming agent and water, and as a result, an increase in the time of extinguishing the fire.

Claims (2)

1. Installation of under-layer fire extinguishing in the tank, including a mortar connected in the technological sequence, equipped with an electric valve, foam pipes equipped with high-pressure foam generators, non-return valves, bursting membranes, while the foam pipes inside the tank are rigidly connected to stationary support pipes, equipped with an internal wiring with foam nozzles, characterized the fact that the foam nozzles are arranged in pairs in vertical planes at a height of 2/3 of the filling level of the tank, When this stationary support tubes are fixed to the tank walls. 2. Installation according to claim 1, characterized in that the pairs of foam nozzles are located opposite each other with respect to a vertical plane passing through the center of the tank and perpendicular to the plane of placement of stationary support pipes.