CN219842181U - Sulfuric acid sampling tank and sulfuric acid production system - Google Patents

Abstract

The utility model provides a sulfuric acid sampling tank and a sulfuric acid production system, and relates to the technical field of chemical equipment. Through setting up overflow reflux assembly on the cell body, after installing overflow pipe and back flow, the overflow pipe is located the cell body inner chamber, and the back flow is located below the bottom plate of cell body, is provided with the overflow port on the top lateral wall of overflow pipe, and the overflow pipe in the groove stores a certain amount of sulfuric acid (liquid level), and the sulfuric acid liquid level is higher than the overflow port on the overflow pipe and passes through the back flow to the circulation tank, realizes the closed loop circulation of sulfuric acid, makes things convenient for the sulfuric acid backward flow, increases the security of sampling operation; the circulating groove can prevent the parking air flow sulfuric acid from spraying on the cover plate at the top of the groove body, and the operation safety can be increased.

Description

Sulfuric acid sampling tank and sulfuric acid production system

Technical Field

The utility model relates to the technical field of chemical equipment, in particular to a sulfuric acid sampling tank and a sulfuric acid production system.

Background

In the sulfuric acid production process, observation and sampling are needed, and the observation is generally carried out by opening a cover plate and naked eyes, and the sampling bottle stretches into a sampling groove for sampling through iron wire binding. The main problems of such an observation sampling system are: when the emergency stop is carried out, the pressure in the circulating tank is too high, so that sulfuric acid in the sampling tank is sprayed out by air flow, the air flow is splashed with acid liquor, people are easy to hurt, and the acid liquor sprayed out of the sampling tank corrodes the sampling tank and the circulating tank platform.

In addition, the existing observation sampling system has the following problems:

(1) In the sulfuric acid production industry, the sampling tank belongs to an open device, and the sampling tank is severely corroded due to the fact that sulfuric acid is in contact with air for a long time.

(2) The cover plate is required to be opened when the sulfuric acid state of the sampling tank is observed, and the safety risk of sulfuric acid burn exists.

(3) The sampling process is complex in operation, the sampling bottle is required to stretch into sulfuric acid, and the sulfuric acid is not easy to treat due to the adhesion of the sampling bottle.

(4) The sampling groove is non-standard manufacturing equipment, and in the actual production operation process, the sampling groove is corroded and damaged due to leakage of vibration conditions, the service life of the sampling groove after maintenance is short, and the whole equipment needs to be replaced.

In view of this, the present utility model has been proposed.

Disclosure of Invention

The utility model aims to provide a sulfuric acid sampling tank and a sulfuric acid production system, which aim to improve the safety of the operation of the sampling tank.

Embodiments of the present utility model are implemented as follows:

in a first aspect, the utility model provides a sulfuric acid sampling tank, which comprises a tank body and an overflow reflux assembly, wherein a liquid inlet assembly and a sampling assembly are arranged on the tank body, the overflow reflux assembly comprises an overflow pipe and a reflux pipe, the overflow pipe is positioned in an inner cavity of the tank body, the reflux pipe is positioned below a bottom plate of the tank body, the bottom of the overflow pipe is connected with the top of the reflux pipe, and at least one overflow port is arranged on the side wall of the top of the overflow pipe;

the top of overflow pipe is provided with the overflow apron that is used for the confined, and the bottom of back flow is used for connecting the circulation groove.

In an alternative embodiment, the overflow ports are two oppositely disposed.

In an alternative embodiment, the overflow cover plate has a diameter that is larger than the diameter of the overflow pipe.

In an alternative embodiment, both the overflow pipe and the return pipe are secured to the floor of the tank by flanges.

In an alternative embodiment, a tank cover plate is mounted on top of the tank, and a sight glass for observing conditions in the tank is arranged on the tank cover plate.

In an alternative embodiment, a connecting rod is arranged on the groove body cover plate, one end of the connecting rod is connected with a hinge, and the other end of the connecting rod is connected with the groove body through a compression bolt.

In an alternative embodiment, the liquid inlet assembly comprises a liquid inlet pipe, a connecting hose and a control valve, wherein the control valve is arranged between the sulfuric acid conveying pipeline and the connecting hose, the liquid inlet end of the liquid inlet pipe is connected with the connecting hose, and the liquid outlet end of the liquid inlet pipe extends into the inner cavity of the tank body.

In an alternative embodiment, the sampling assembly comprises a sampling hose and a sampling valve, the side wall of the tank body is provided with a lower liquid outlet, the sampling valve is arranged at the lower liquid outlet, the sampling hose is provided with a first end and a second end which are oppositely arranged, and the first end of the sampling hose is connected with the sampling valve.

In an alternative embodiment, an upper liquid outlet is further provided on the side wall of the tank body, and the upper liquid outlet is detachably connected with the second end of the sampling hose.

In a second aspect, the present utility model provides a sulfuric acid production system comprising the sulfuric acid sampling tank of any of the preceding embodiments.

The embodiment of the utility model has the beneficial effects that: through setting up overflow reflux assembly on the cell body, after installing overflow pipe and back flow, the overflow pipe is located the cell body inner chamber, and the back flow is located below the bottom plate of cell body, is provided with the overflow port on the top lateral wall of overflow pipe, and the overflow pipe in the groove stores a certain amount of sulfuric acid (liquid level), and the sulfuric acid liquid level is higher than the overflow port on the overflow pipe and passes through the back flow to the circulation tank, realizes the closed loop circulation of sulfuric acid, makes things convenient for the sulfuric acid backward flow, increases the security of sampling operation; the circulating groove can prevent the parking air flow sulfuric acid from spraying on the cover plate at the top of the groove body, and the operation safety can be increased.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present utility model and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a sulfuric acid sampling tank according to an embodiment of the present utility model;

FIG. 2 is a schematic view of the top of the tank in FIG. 1;

FIG. 3 is a schematic view of the structure of the base plate in FIG. 1;

FIG. 4 is a perspective view of the sulfuric acid sampling tank of FIG. 1;

FIG. 5 is a side view of the sulfuric acid sampling tank of FIG. 1;

FIG. 6 is a schematic view of the overflow tube of FIG. 1;

fig. 7 is a schematic view of the structure of the return pipe in fig. 1.

Icon is 100-sulfuric acid sampling groove; 110-a tank body; 111-a groove cover plate; 112-viewing mirror; 113-a connecting rod; 114-loose leaves; 115-a compression bolt; 116-a lower liquid outlet; 117-upper outlet; 118-floor; 120-overflow return assembly; 121-overflow pipe; 122-return pipe; 123-overflow port; 124-overflow cover plate; 130-a liquid inlet component; 131-a liquid inlet pipe; 132-connecting a hose; 133-control valve; 140-sampling assembly; 141-a sampling hose; 142-sampling valve; 200-circulation tank.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. The components of the embodiments of the present utility model generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the utility model, as presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or those that are conventionally put in use of the inventive product, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal," "vertical," and the like do not denote a requirement that the component be absolutely horizontal or overhang, but rather may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present utility model, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

Referring to fig. 1, an embodiment of the present utility model provides a sulfuric acid sampling tank 100, which includes a tank body 110, a liquid inlet assembly 130, an overflow reflux assembly 120 and a sampling assembly 140, so as to realize modular design, manufacture, assembly, maintenance and the like of the sulfuric acid sampling tank.

The main functions of the tank 110 are to realize sulfuric acid sample injection, connection of sampling accessories and storage of sulfuric acid, and the tank is in a cylindrical structure. Referring to fig. 1 and 2, a tank cover 111 is mounted on top of the tank 110, and a sight glass 112 for observing conditions in the tank is disposed on the tank cover 111.

Specifically, the sight glass 112 is installed by pressing bolts, so that the condition in the tank body 110 can be observed under the condition that the tank body cover plate 111 is not opened, and the condition of flowing, color, foam and the like of the sulfuric acid appearance in the tank body 110 can be observed.

Further, a connecting rod 113 is arranged on the groove body cover plate 111, one end of the connecting rod 113 is connected with a hinge 114, and the other end of the connecting rod 113 is connected with the groove body 110 through a compression bolt 115. The groove cover 111 can fix the connecting rod 113 in a welding mode, one end of the connecting rod 113 is connected to the hinge 114 through a bolt, and the other end of the connecting rod 113 is pressed with the groove 110 through the pressing bolt 115. The groove cover plate 111 is opened and closed through the hinge 114, the pressing bolt 115 seals and presses the groove cover plate 111, and the groove cover plate 111 and the groove 110 are sealed by using a tetrafluoro expansion belt. The inside of the tank body 110 is completely isolated from the outside, so that the condition that sulfuric acid splashes outside due to the corrosion of dilute acid in the tank is reduced, and the operation safety of the device is improved.

As shown in fig. 1 and 3, the tank body 110 is provided with a bottom plate 118, the bottom of which is sealed, and the bottom plate 118 is provided with only connection holes for connection with a flange.

The liquid inlet assembly 130 is used for inputting concentrated sulfuric acid into the tank body 110, the liquid inlet assembly 130 comprises a liquid inlet pipe 131, a connecting hose 132 and a control valve 133, the control valve 133 is arranged between the sulfuric acid conveying pipeline and the connecting hose 132, the liquid inlet end of the liquid inlet pipe 131 is connected with the connecting hose 132, and the liquid outlet end of the liquid inlet pipe 131 extends into the inner cavity of the tank body 110. Concentrated sulfuric acid conveyed from the sulfuric acid conveying pipeline is conveyed into the liquid inlet pipe 131 through the connecting hose 132, and then conveyed into the tank body 110, and the opening and closing are controlled by the control valve 133.

In particular, the control valve 133 may be an existing fluorine lined ball valve for controlling flow. The fluorine lining ball valve and the main pipeline can be connected through a flange. The connection hose 132 may be a stainless steel wound hose or a sulfuric acid corrosion resistant steel wire hose, but is not limited thereto. The connecting hose 132 can be in threaded connection with the liquid inlet pipe 131, and the problem of loosening of a flange and acid leakage caused by welding seam cracking due to vibration of a hard pipe connecting sampling groove is solved through hose connection.

Specifically, the inner and outer parts of the liquid inlet on the tank body 110 are welded with inner wires, quick threaded connection is adopted, quick disassembly and replacement are realized, threaded connection is adopted in the inner part, and the liquid inlet pipe 131 stretches into the position below the sulfuric acid liquid level.

Referring to fig. 1, 4 and 5, the overflow return assembly 120 includes an overflow pipe 121 and a return pipe 122, the overflow pipe 121 is located in the inner cavity of the tank 110, the return pipe 122 is located below the bottom plate of the tank 110, the bottom of the overflow pipe 121 is connected with the top of the return pipe 122, at least one overflow port 123 is provided on the top sidewall of the overflow pipe 121, and the bottom of the return pipe 122 is used for connecting with the circulation tank 200 below.

It should be noted that, sulfuric acid enters the tank body 110 through the liquid inlet pipe 131, the liquid level in the tank body 110 reaches the overflow port 123, then enters the overflow pipe 121, and enters the circulation tank 200 through the return pipe 122 below, so as to realize closed loop circulation of sulfuric acid, facilitate sulfuric acid backflow and prevent the sulfuric acid from spraying on the tank cover plate 111 due to the parking air flow. The circulation tank 200 is much larger in volume than the tank body 110, and only a part of the structure is shown in the figure.

After the vehicle is stopped, the negative pressure pipeline fan and the circulating acid pump are stopped, sulfuric acid in the tower flows into the circulating tank 200 in a short time, the sulfuric acid in the circulating tank 200 is instantaneously increased by one half, the pressure of gas in the tower is increased due to the volume compression, the pressure in the circulating tank 200 is increased, and the gas is discharged outwards through the negative pressure pipeline and the reflux pipeline. The closed environment of the sampling tank and the circulating tank 200 have the same integral pressure, so that the gas does not enter the sampling tank any more and is discharged only through the negative pressure pipeline, and the splashing of sulfuric acid caused by the ejection of the gas flow from the overflow pipe 121 is prevented.

Specifically, the flange is provided on the bottom plate 118, and the overflow pipe 121 and the return pipe 122 are connected with the flange hole of the bottom plate 118 through gaskets (such as a tetrafluoro gasket) and bolts.

In some embodiments, the overflow port 123 may be two oppositely disposed, but is not limited thereto, and may be disposed as desired.

Referring to fig. 1 and 6-7, the bottom of the overflow pipe 121 is welded with a flange using a pipe, and the top of the overflow pipe 121 is provided with an overflow cover plate 124 for sealing, and the diameter of the overflow cover plate 124 is larger than that of the overflow pipe 121. The two-end pipes of the return pipe 122 are welded using flanges, and connect the bottom plate 118 and the flanges. The overflow pipe 121 is detached after being mounted by bolts, the bolt heads are fully welded for 2 layers, and then the overflow pipe 121 is connected with the bottom plate 118 and the return pipe 122 by bolts.

Specifically, the contact surfaces of the liquid inlet pipe 131, the tank cover 111, the sight glass 112, the hinge 114 and the compression bolt 115 with the tank 110 are sealed by using a polytetrafluoroethylene expansion belt.

The sampling assembly 140 is used for sampling from the tank 110. The sampling assembly 140 includes a sampling hose 141 and a sampling valve 142, a lower liquid outlet 116 is disposed on a sidewall of the tank 110, the sampling valve 142 is mounted at the lower liquid outlet 116, the sampling hose 141 has a first end and a second end which are disposed opposite to each other, and the first end of the sampling hose 141 is connected to the sampling valve 142. At the time of sampling, the sampling valve 142 is opened, and flows into a specific container through the sampling hose 141. The sampling valve 142 is used as an acid discharge port of the sulfuric acid tank, and discharges sulfuric acid in the tank during maintenance and cleaning operations. Sampling assembly 140 need not follow cell body 110 inside sample, has reduced the direct contact of sampler personnel and sulfuric acid, leads to the probability of taking place the incident, realizes safe sample.

In particular, the sampling hose 141 may be a stainless steel wound hose or a sulfuric acid corrosion resistant steel wire hose.

In some embodiments, an upper outlet 117 is further provided on the sidewall of the tank 110, and the upper outlet 117 is detachably connected to the second end of the sampling hose 141. Thus, when sampling is required, the sampling hose 141 is removed from the upper liquid outlet 117 to perform sampling operation; when sampling is not performed, the sampling hose 141 is installed at the upper liquid outlet 117.

In operation, the bottom and top sides of the tank 110 are perforated and an external thread is welded to the tank holes and connected to the sampling valve 142. The sampling valve 142 is connected to the sampling hose 141, and the upper liquid outlet 117 is connected to the sampling hose 141. The control valve 133 is opened, the sampling hose 141 and the upper liquid outlet 117 are loosened, the sampling hose 141 is connected with a sampling device, the sampling valve 142 is opened, the sulfuric acid sampling is nearly completed, the sampling valve 142 is closed, and the upper liquid outlet 117 is restored after the sampling hose 141 is completely drained. When the sampling tank needs to be maintained and cleaned, the control valve 133 is closed, and acid discharge of the sampling tank is realized according to the sampling operation.

It is to be added that the embodiment of the utility model realizes the maintenance and replacement of the parts of the vulnerable part by modularized installation, thereby reducing the overall maintenance difficulty and replacement cost of the sampling groove.

The embodiment of the utility model also provides a method for realizing the sulfuric acid sampling and observing sampling groove, which comprises the following steps:

(1) Opening the control valve 133, and allowing sulfuric acid to flow into the tank body 110 through the liquid inlet pipe 131;

(2) Sulfuric acid enters the tank body 110 and is stored in the tank body 110 to form a certain liquid level;

(3) The sulfuric acid level rises to an overflow port 123 on the overflow pipe 121 and flows back to the circulation tank 200 through the return pipe 122;

(4) The sulfuric acid in the sulfuric acid tank is sampled by opening and closing a sampling valve 142;

(5) The sulfuric acid cover plate sight glass can observe the color, flow and foam conditions in the sulfuric acid tank.

The embodiment of the utility model also provides a sulfuric acid production system which comprises a sulfuric acid sampling tank 100, a sulfuric acid conveying pipeline, reaction equipment and the like.

Case one

In the installation process of the sampling tank, each component is manufactured according to the requirements, namely a return pipe 122, a bottom plate 118, an overflow pipe 121, a tank body 110, a liquid inlet pipe 131, a tank body cover plate 111, an upper liquid outlet 117 and a lower liquid outlet 116; the welding involved is stainless steel welding, and the punching is completed by mechanical drilling.

Purchasing a finished product, comprising: a fluorine lined ball valve (control valve 133), sight glass 112, sampling valve 142, stainless steel winding hose (connection hose 132), stainless steel winding hose (sampling hose 141), manufacturing standard flange, stainless steel bolt, tetrafluoro gasket, expanded tetrafluoro band, and internal thread joint. The overflow pipe 121 is positioned with the bottom plate 118 by stainless steel bolts, the stainless steel bolts are welded, the welding is completed, and the return pipe 122, the bottom plate 118, the overflow pipe 121 and the tetrafluoro gasket are connected by the positioned bolts. The upper liquid outlet 117 and the lower liquid outlet 116 are respectively welded with an internal thread joint, the lower liquid outlet 116 is connected by a sampling valve 142, and a stainless steel winding hose is connected with the sampling valve 142 and the upper liquid outlet 117. The sight glass 112 is installed at the opening of the groove body cover plate 111 through bolts, the groove body cover plate 111 and the liquid inlet pipe 131 are directly welded with inner wires, and the liquid inlet pipe 131 is connected through a wire opening, so that replacement operation is facilitated. The cover 111 and the cover 110 are fixed and positioned at the hinge 114 by bolts, and the sampling tank is connected and fixed with the circulation tank 200 after the installation. The fluorine lining ball valve is connected with the sulfuric acid pipeline, the flange end of the stainless steel winding hose is connected with the fluorine lining ball valve, and the other end of the stainless steel winding hose is connected with the liquid inlet pipe 131 through an external wire. After the installation, the fluorine lining ball valve is closed, the sampling valve 142, the joint of the return pipe 122 and the circulation tank 200 is plugged, the tank cover plate 111 is sealed with the tank body through an expansion tetrafluoro belt, and the compression bolt 115 compresses tightly. After the above steps are completed, air is pumped through the upper liquid outlet 117 to test leakage, the pressure is 0.1Mpa, and the pressure is stabilized for 20 minutes.

Case two

And in the process of inspecting and sampling sulfuric acid production, during normal production of a sulfuric acid production line, the appearance of the sulfuric acid needs to be primarily observed and judged every 8 hours, and meanwhile, the concentration of the sulfuric acid is subjected to assay analysis. After the sampling tank pressure test is finished, the blind plate of the return pipe 122 is removed, the return pipe 122 is connected with the circulation tank 200, a stainless steel winding hose is connected with the upper liquid outlet 117, a fluorine lining ball valve is opened to 1/2, the sulfuric acid inflow condition of the liquid inlet pipe 131 is observed through the sight glass 112, the sulfuric acid rises to the height of the overflow port 123 of the overflow pipe 121, the liquid level rising condition is observed, the fluorine lining ball valve is closed when the liquid level rises, and if the liquid level is stable and unchanged, the fluorine lining ball valve is not adjusted. Sulfuric acid enters the sampling tank through the liquid inlet pipe 131 and flows back to the circulation tank 200 through the overflow pipe 121, so that the internal circulation of sulfuric acid is completed. The upper liquid outlet 117 is loosened, the stainless steel winding hose outlet is connected with a sampling bottle, the sampling valve 142 is opened, sulfuric acid flows into the sampling bottle from the sampling tank, the sampling valve 142 is closed in advance when the sampling bottle reaches the liquid level, residual sulfuric acid in the stainless steel winding hose is drained, and connection with the upper liquid outlet 117 is restored. During the inspection process, the daytime operator can observe the flowing condition of the sulfuric acid in the sampling tank through the sight glass 112, and the appearance of the sulfuric acid foam, the size, the color and the like; the lighting equipment needs to be carried at night so as to be convenient for observation through the sight glass.

Three kinds of cases

In the maintenance process of the sampling groove, the sulfuric acid sampling groove has the conditions of sulfuric acid leakage and corrosion in the production process, wherein the stainless steel winding hose, the liquid inlet pipe 131, the fluorine lining ball valve and the sampling valve 142 belong to vulnerable rooms, and the sulfuric acid sampling groove needs to be kept in stock. The flange gasket and the expansion tetrafluoro belt have aging leakage conditions. The accessories and the wearing parts can be conveniently replaced. Taking the replacement of the inlet pipe 131 and the replacement of the cover plate expanded tetrafluoro strip as an example. And closing the fluorine lined ball valve, and observing that no sulfuric acid flows in. The upper outlet 117 is opened and the sampling valve 142 is opened to place the sulfuric acid in the sampling tank into the sulfuric acid container. After the sulfuric acid in the sampling tank is exhausted, the pressing bolt 115 is loosened, and the tank cover 111 is opened. The inlet pipe 131 is removed and replaced with a new inlet pipe. The original expansion tetrafluoro belt is cleaned up and replaced by a new expansion tetrafluoro belt. The tank cover 111 is closed and the compression bolts 115 compress. The sampling valve 142 is closed and the stainless steel wire hose is returned to connection with the upper outlet 117. The semi-open lining fluorine ball valve observes the inflow of sulfuric acid and the leakage of the sealing surface of the groove cover plate 111. And (5) carrying out normal inspection and sampling operation without leakage.

The above is only a preferred embodiment of the present utility model, and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (10)

1. The sulfuric acid sampling tank is characterized by comprising a tank body and an overflow reflux assembly, wherein a liquid inlet assembly and a sampling assembly are arranged on the tank body, the overflow reflux assembly comprises an overflow pipe and a reflux pipe, the overflow pipe is positioned in an inner cavity of the tank body, the reflux pipe is positioned below a bottom plate of the tank body, the bottom of the overflow pipe is connected with the top of the reflux pipe, and at least one overflow port is arranged on the side wall of the top of the overflow pipe;

the top of overflow pipe is provided with the overflow apron that is used for the confined, the bottom of back flow is used for connecting the circulation groove.

2. A sulfuric acid sampling tank according to claim 1, wherein the overflow ports are two oppositely disposed.

3. A sulfuric acid sampling tank according to claim 1 or 2, characterized in that the overflow cover plate has a diameter larger than the diameter of the overflow pipe.

4. A sulfuric acid sampling tank according to claim 3, characterized in that the overflow pipe and the return pipe are both fixed to the bottom plate of the tank body by means of flanges.

5. The sulfuric acid sampling tank according to claim 1, wherein a tank cover plate is mounted on the top of the tank body, and a sight glass for observing conditions in the tank is arranged on the tank cover plate.

6. The sulfuric acid sampling tank according to claim 5, wherein a connecting rod is arranged on the tank cover plate, one end of the connecting rod is connected with a hinge, and the other end of the connecting rod is connected with the tank body through a compression bolt.

7. The sulfuric acid sampling tank of claim 1, wherein the liquid inlet assembly comprises a liquid inlet pipe, a connecting hose and a control valve, the control valve is arranged between a sulfuric acid conveying pipeline and the connecting hose, the liquid inlet end of the liquid inlet pipe is connected with the connecting hose, and the liquid outlet end of the liquid inlet pipe extends into the inner cavity of the tank body.

8. A sulfuric acid sampling tank according to claim 1, wherein the sampling assembly comprises a sampling hose and a sampling valve, a lower liquid outlet is provided on a side wall of the tank body, the sampling valve is mounted at the lower liquid outlet, the sampling hose has a first end and a second end which are oppositely arranged, and the first end of the sampling hose is connected with the sampling valve.

9. The sulfuric acid sampling tank of claim 8, wherein an upper liquid outlet is further provided on a side wall of the tank body, and the upper liquid outlet is detachably connected with the second end of the sampling hose.

10. A sulfuric acid production system comprising the sulfuric acid sampling tank of any one of claims 1-9.