Water seal type storage tank fire-retardant breather valve

Abstract

The utility model discloses a water seal type storage tank fire-retardant breather valve which comprises a box body, a buffer chamber, a negative pressure chamber and a positive pressure chamber are sequentially arranged in the box body, the buffer chamber is communicated with the upper portion of the negative pressure chamber, the negative pressure chamber is communicated with the bottom of the positive pressure chamber, the negative pressure chamber and the positive pressure chamber are filled with liquid, and the negative pressure chamber is communicated with the negative pressure chamber. An air pipe is connected to the upper portion of the buffer chamber, a pipeline located in the negative pressure chamber is inserted into the top of the negative pressure chamber, the pipeline can move up and down to adjust the height of the pipeline in the negative pressure chamber, the top of the pipeline is of an elbow structure, and an elbow communicated with the negative pressure chamber is arranged on the upper left portion of the positive pressure chamber. The bottom of the elbow is connected with a straight pipe which can move up and down to adjust the height of the elbow in the positive pressure chamber, and an exhaust hole is formed in the top of the positive pressure chamber. According to the equipment, positive and negative pressure parameters set by the fire-retardant breather valve can be accurately expressed in a water column mode, and the convenience and accuracy of operation are improved.

Description

Technical Field

[0001] This utility model relates to the technical field of flame-arresting breather valves for ensuring the safety of storage tanks, and in particular to a water-sealed flame-arresting breather valve for storage tanks. Background Technology

[0002] Atmospheric pressure storage tanks for Class A and B flammable, explosive, toxic and harmful chemicals are usually equipped with nitrogen sealing devices at the top of the tank to reduce material loss, environmental pollution from gas leaks, and fire accidents during storage.

[0003] A typical nitrogen blanketing system consists of a nitrogen supply valve, a flame arrestor single-exit valve, and a flame arrestor breather valve. The nitrogen supply valve and the single-exit valve primarily constitute the gaseous nitrogen blanketing environment at the top of the storage tank. Specifically, the nitrogen supply valve uses a self-regulating balancing valve and a check valve, programmed to supply nitrogen to the gaseous space at the top of the tank only when the gas pressure is below a set value, and stops supplying nitrogen when the set gas pressure is reached. The single-exit valve employs a mechanical design with a flame arrester. When the gas pressure at the top of the tank exceeds the set value, the single-exit valve automatically opens to release gas. When the released gas reaches the set lower limit, the valve automatically closes to stop releasing gas. The gas released by the single-exit valve is led to the waste gas treatment system for processing through connecting pipelines.

[0004] Within the range set by the nitrogen supply valve and the single-exit valve, the gas phase at the top of the storage tank remains closed to the environment. However, to prevent deformation of the storage tank body due to excessive negative pressure in the gas phase caused by insufficient nitrogen supply from the nitrogen supply valve exceeding the tank's design strength, and to prevent deformation of the tank body due to insufficient venting capacity of the single-exit valve caused by excessive positive pressure inside the storage tank exceeding the tank's design strength, the following measures are taken:

[0005] Storage tanks equipped with nitrogen blanketing at atmospheric pressure must, in addition to the nitrogen supply valve and single-exit valve, also include a flame arrestor breather valve for safety. The positive and negative pressure range of the flame arrestor breather valve exceeds that of the nitrogen supply valve and single-exit valve. When the positive pressure exceeds the valve's setting limit, it opens to release emergency air into the environment to reduce pressure. It automatically closes and stops releasing air when the pressure inside the tank reaches the set lower limit. When the negative pressure inside the tank exceeds the valve's setting limit, it opens to draw air into the environment. It automatically closes and stops drawing air when the pressure reaches the set lower limit.

[0006] Therefore, it is crucial that the positive and negative setting ranges of the flame arrestor breather valve match its actual operating range. If the actual positive pressure operating range differs from the setting range, failure to activate the emergency venting mechanism when the pressure exceeds the positive setting range may cause the pressure inside the tank to exceed its design strength, leading to a deformation hazard. Similarly, if the actual negative pressure operating range differs from the setting range, failure to activate the emergency suction mechanism when the pressure exceeds the negative setting range may cause the negative pressure inside the tank to exceed its design strength, also resulting in a deformation hazard.

[0007] Furthermore, if the actual operation of the flame arrestor breather valve falls within the pressure range set by the single-exit valve, it will open simultaneously with a portion of the single-exit valve, causing direct emissions of gas from the storage tank into the environment and increasing environmental pollution. If the flame arrestor breather valve opens within the negative pressure range set by the nitrogen supply valve, it will draw in ambient air, reducing the nitrogen supply and decreasing the nitrogen sealing effect within the storage tank. Utility Model Content

[0008] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a water-sealed flame arrestor breather valve for storage tanks that allows for convenient and precise pressure adjustment while maintaining good sealing performance.

[0009] This utility model discloses a water-sealed storage tank flame arrestor breather valve, which includes a housing. A buffer chamber, a negative pressure chamber, and a positive pressure chamber are sequentially arranged inside the housing. The buffer chamber communicates with the upper part of the negative pressure chamber, and the negative pressure chamber communicates with the bottom of the positive pressure chamber. Both the negative and positive pressure chambers are filled with liquid. An air pipe is connected to the upper part of the buffer chamber. A pipe located inside the negative pressure chamber is inserted into the top of the negative pressure chamber. The top of the pipe has an elbow structure, and the pipe can move up and down to adjust its height within the negative pressure chamber. An elbow communicating with the negative pressure chamber is provided in the upper left part of the positive pressure chamber. A straight pipe that can move up and down to adjust its height within the positive pressure chamber is connected to the bottom of the elbow. An exhaust port is provided at the top of the positive pressure chamber.

[0010] According to some embodiments of this utility model, an observation window is provided on the top of the negative pressure chamber.

[0011] According to some embodiments of this utility model, a drain valve is installed at the bottom of the buffer chamber.

[0012] According to some embodiments of this utility model, the pipe is installed in the negative pressure chamber by a sealing ring.

[0013] According to some embodiments of this utility model, the straight pipe is sealed and installed on the elbow by a sealing ring.

[0014] According to some embodiments of this utility model, an overflow pipe is installed on the right side of the positive pressure chamber.

[0015] According to some embodiments of this utility model, a water replenishment float valve is installed on the right side of the positive pressure chamber.

[0016] According to some embodiments of this utility model, a drain valve is installed at the bottom of the positive pressure chamber.

[0017] According to some embodiments of this utility model, the trachea and the pipe have the same diameter.

[0018] According to some embodiments of this utility model, the pipe has the same diameter as the straight pipe.

[0019] This invention offers at least the following advantages: This product allows for precise adjustment of the positive and negative gas phase pressure control within the storage tank by adjusting the insertion depth of the pipe and straight pipe into the water seal. It facilitates easy and accurate adjustment of the water seal depth based on the positive and negative pressure settings on the storage tank, ensuring gas leakage within the set range and timely release or replenishment of gas when the pressure exceeds the set range. Furthermore, this equipment accurately expresses the positive and negative pressure parameters set by the flame arrestor breather valve using a water column, improving operational convenience and accuracy.

[0020] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0022] Figure 1 The working principle diagram of this utility model is shown when the pressure inside the storage tank is low.

[0023] Figure 2 This is a schematic diagram illustrating the working principle of this invention when the pressure inside the storage tank is high. Detailed Implementation

[0024] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0025] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, etc., are based on the directional or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0026] In the description of this utility model, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features or their sequential relationship.

[0027] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0028] Reference Figure 1 , Figure 2 A water-sealed flame arrestor breather valve for a storage tank includes a housing divided into three spaces: a buffer chamber 1, a negative pressure chamber 2, and a positive pressure chamber 3. The buffer chamber 1 is connected to the upper part of the negative pressure chamber 2, and the negative pressure chamber 2 is connected to the bottom of the positive pressure chamber 3. Both the negative pressure chamber 2 and the positive pressure chamber 3 are filled with liquid. A gas pipe 11 connected to the top of the storage tank is provided at the upper part of the buffer chamber 1. Gas leaking from the top of the storage tank and gas absorbed from the environment enter the storage tank through the buffer chamber 1. The main function of the buffer chamber 1 is to allow the gas entering and leaving the storage tank to remain in the buffer chamber. During the gas phase process of sealing the storage tank, part of the gas leaking from the storage tank condenses into liquid in the buffer chamber. When the gas is drawn into the storage tank through the water seal, part of the water vapor condenses in the buffer chamber 1, reducing the water vapor brought into the storage tank. The buffer chamber 1 simultaneously withstands negative and positive pressure. A pipe 22 is inserted into the top of the negative pressure chamber 2, located inside the chamber. The top of the pipe 22 is an elbow, and the pipe 22 can be moved up and down to adjust its height within the negative pressure chamber 2. The main function of the negative pressure chamber 2 is to convert the maximum negative pressure into the height of a water column and adjust the depth of the pipe 22 inserted into the water seal. When the storage tank reaches the maximum negative pressure, refer to... Figure 1 Air is drawn from the environment, enters buffer chamber 1 through pipe 22, and then enters the storage tank; when under positive pressure, refer to... Figure 2 The water column height in pipe 22 increases with the pressure, making the gas phase space of negative pressure chamber 2 a closed space. A bend 32 communicating with negative pressure chamber 2 is provided in the upper left part of positive pressure chamber 3. The bottom of bend 32 is connected to a straight pipe 33 that can move up and down to adjust its height in positive pressure chamber 3. An exhaust port 31 is provided at the top of positive pressure chamber 3. The operator can adjust the height of the straight pipe 33 inserted into positive pressure chamber 3 according to the maximum positive pressure parameter in the storage tank through the exhaust port 31. The main function of positive pressure chamber 3 is to convert the maximum positive pressure into water column height and adjust its insertion into the water seal. When the storage tank reaches the maximum positive pressure, refer to... Figure 2 The discharged gas exits the positive pressure chamber 3 through the vent 31 via a straight pipe 33 inserted to the set water seal depth. When the storage tank is under negative pressure, refer to... Figure 1 The water column height in straight pipe 33 increases according to the negative pressure it receives, and the gas phase space in positive pressure chamber 3 is an open space that is connected to the environment.

[0029] For ease of operation, an observation window 21 is provided at the top of the negative pressure chamber 2. The operator can move the pipe 22 up and down according to the maximum negative pressure parameter in the storage tank and observe through the observation window 21 to adjust its height in the negative pressure chamber 2.

[0030] A drain valve 12 is installed at the bottom of the buffer chamber 1. The drain valve 12 periodically drains the liquid that condenses in the buffer chamber.

[0031] To ensure a tight seal between the sidewall of pipe 22 and the negative pressure chamber 2, pipe 22 is sealed and installed inside the negative pressure chamber 2 using a sealing ring. Similarly, straight pipe 33 is also sealed and installed on elbow 32 using a sealing ring.

[0032] Because the negative pressure chamber 2 and positive pressure chamber 3 are connected to the leaking gas in the storage tank, while preventing gas leakage, a small amount of gas will dissolve into the water and condense on the upper layer of the water seal. Therefore, a drain valve 36 is installed at the bottom of the positive pressure chamber 3. The drain valve 36 is opened periodically to drain the water seal. After draining, a water replenishment float valve 35 is installed on the right side of the positive pressure chamber 3. The water replenishment float valve 35 ensures that the water replenishment height is precisely at the water seal level. An overflow pipe 34 is installed on the right side of the positive pressure chamber 3, and the height of the overflow pipe 34 is slightly higher than the water seal level.

[0033] The trachea 11 has the same diameter as the pipe 22 and the straight pipe 33, which facilitates the calculation of the amount of gas inhaled and exhaled.

[0034] Assuming the flame arrestor breather valve in the storage tank is designed to operate at pressures ranging from -295 Pa to +1750 Pa, when the lowest negative pressure inside the tank is below -295 Pa, the tank needs to replenish air from the environment to bring the internal pressure above -295 Pa before closing. When the internal pressure exceeds 1750 Pa, the tank needs to release gas into the environment to bring the internal pressure below 1750 Pa. Based on the principle that 1 Pa equals 0.1 mm water column, and according to design requirements, pipe 22 of negative pressure chamber 2 is adjusted to be inserted at a depth of -29.5 mm underwater, and straight pipe 33 of positive pressure chamber 3 is adjusted to be inserted at a depth of 175 mm underwater.

[0035] When the pressure inside the storage tank is below -295 Pa, the straight pipe 33 of the negative pressure chamber 2 and the positive pressure chamber 3 is subjected to a negative pressure below -295 Pa, as shown in the reference. Figure 1 The ambient atmosphere will pass through the pipe 22 of the negative pressure chamber 2 and enter the negative pressure chamber 2 and buffer chamber 1 before entering the storage tank. When the gas passes through the pipe 22 of the negative pressure chamber 2, the volume of the water seal water decreases. At the same time, the straight pipe 33 of the positive pressure chamber 3 is subjected to the same negative pressure, causing the water seal water in the straight pipe 33 to rise. Since the pipe 22 and the straight pipe 33 have the same diameter, the height of the fall is equal to the height of the rise, and the water seal water level remains unchanged.

[0036] When the pressure inside the storage tank exceeds +1750 Pa, the straight pipe 33 of the negative pressure chamber 2 and the positive pressure chamber 3 is subjected to a positive pressure exceeding +1750 Pa, as shown in the reference. Figure 2The gas in the storage tank will pass through buffer chamber 1 and negative pressure chamber 2, and then enter the straight pipe 33 of positive pressure chamber 3, passing through the water seal liquid level and entering the ambient atmosphere. When the gas passes through pipe 22 in negative pressure chamber 2, the volume of water seal water rises. At the same time, the straight pipe 33 in positive pressure chamber 3 is subjected to the same positive pressure, causing the water seal water in the straight pipe 33 to rise. Since pipe 22 and straight pipe 33 have the same diameter, the falling height is equal to the rising height, and the water seal water level remains unchanged.

[0037] This product allows for precise adjustment of the positive and negative gas phase pressure control within the storage tank by adjusting the insertion depth of pipe 22 and straight pipe 33 into the water seal. For example, when the positive pressure inside the storage tank is set to >1750Pa, the gas is vented through the breather valve. The straight pipe 33 of the positive pressure chamber 3 is inserted into the water seal to a depth of 175mm. When the gas phase pressure above the storage tank exceeds 1750Pa, the gas in the tank passes through buffer chamber 1, negative pressure chamber 2, and the 175mm water seal in the positive pressure chamber before being discharged from the vent 31 of the positive pressure chamber 3. When the minimum negative gas phase pressure inside the storage tank is set to <-295Pa, and the gas phase pressure above the storage tank is below -295Pa, the gas drawn in from pipe 22 of the negative pressure chamber 2 enters the negative pressure chamber 2, passes through the 29.5mm water seal, then through buffer chamber 1, and finally enters the tank through the flame arrestor breather valve. When the pressure inside the tank is between -295Pa and 1750Pa, the water seals in the positive pressure chamber 3 and negative pressure chamber 2 seal the gas inside the storage tank, preventing leakage.

[0038] This invention proposes a method for easily and accurately adjusting the water seal depth based on the positive and negative pressure settings on a storage tank. This ensures that gas leakage is prevented within the set range, while simultaneously ensuring that gas is promptly released from or replenished into the tank when the pressure exceeds the set range. This device can precisely express the positive and negative pressure parameters set by the flame arrestor breather valve using a water column, improving operational convenience and accuracy.

[0039] The preferred embodiments of this utility model have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of this utility model without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of this utility model through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A water-sealed flame arrestor breather valve for a storage tank, characterized in that, The device includes a housing, which contains a buffer chamber (1), a negative pressure chamber (2), and a positive pressure chamber (3) arranged sequentially. The buffer chamber (1) is connected to the upper part of the negative pressure chamber (2), and the negative pressure chamber (2) is connected to the bottom of the positive pressure chamber (3). The negative pressure chamber (2) and the positive pressure chamber (3) are filled with liquid. The upper part of the buffer chamber (1) is connected to an air pipe (11). The top of the negative pressure chamber (2) is connected to a pipe (22) located inside the negative pressure chamber (2). The pipe (22) can be moved up and down to adjust its height in the negative pressure chamber (2). The top of the pipe (22) is a bend. The upper left part of the positive pressure chamber (3) is provided with a bend (32) that communicates with the negative pressure chamber (2). The bottom of the bend (32) is connected to a straight pipe (33) that can be moved up and down to adjust its height in the positive pressure chamber (3). The top of the positive pressure chamber (3) is provided with an exhaust port (31).

2. The water-sealed storage tank flame arrestor breather valve according to claim 1, characterized in that, The negative pressure chamber (2) is provided with an observation window (21) at the top.

3. The water-sealed storage tank flame arrestor breather valve according to claim 1, characterized in that, A drain valve (12) is installed at the bottom of the buffer chamber (1).

4. A water-sealed storage tank flame arrestor breather valve according to claim 1, characterized in that, The pipe (22) is installed in the negative pressure chamber (2) by a sealing ring.

5. A water-sealed storage tank flame arrestor breather valve according to claim 1, characterized in that, The straight pipe (33) is sealed and installed on the elbow (32) by a sealing ring.

6. A water-sealed storage tank flame arrestor breather valve according to claim 1, characterized in that, An overflow pipe (34) is installed on the right side of the positive pressure chamber (3).

7. A water-sealed storage tank flame arrestor breather valve according to claim 1, characterized in that, A water replenishment float valve (35) is installed on the right side of the positive pressure chamber (3).

8. A water-sealed storage tank flame arrestor breather valve according to claim 1, characterized in that, A drain valve (36) is installed at the bottom of the positive pressure chamber (3).

9. A water-sealed storage tank flame arrestor breather valve according to claim 1, characterized in that, The trachea (11) has the same diameter as the pipe (22).

10. A water-sealed storage tank flame arrestor breather valve according to claim 9, characterized in that, The pipe (22) has the same diameter as the straight pipe (33).

Images