CN215901307U - Mixed acid system - Google Patents
Mixed acid system Download PDFInfo
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- CN215901307U CN215901307U CN202121987855.XU CN202121987855U CN215901307U CN 215901307 U CN215901307 U CN 215901307U CN 202121987855 U CN202121987855 U CN 202121987855U CN 215901307 U CN215901307 U CN 215901307U
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Abstract
The utility model discloses an acid mixing system, which comprises an acid-water mixer, an acid-acid mixer and an acid inlet pipe; the acid inlet pipe is horizontally arranged at the bottom of a side position of one end of the sulfuric acid dry absorption circulation tank body, the acid mixer and the acid water mixer are sequentially arranged in parallel along the acid inlet direction of the acid inlet pipe, the acid dry absorption circulation tank body is vertically inserted into the sulfuric acid dry absorption circulation tank body from the top of the sulfuric acid dry absorption circulation tank body, and the center of a spray hole at the bottommost layer of the acid water mixer and the lower end face of the acid mixer are all level with the horizontal center line of the acid inlet pipe. During production, the tower-out acid entering from the acid inlet pipe is mixed with the acid entering from the acid mixer in series to form a transverse turbulent flow, and then meets a dilution reaction diffusion zone formed by radial injection process water (or dilute sulfuric acid) and the acid-water mixer in vertical acid feeding to instantly complete homogeneous turbulent flow diffusion mixing. The system has the advantages of advanced device, excellent performance, uniform mixed acid, corrosion resistance, durability, convenient manufacture and maintenance, and can realize the long-period safe and stable operation of the device.
Description
Technical Field
The utility model relates to acid mixing equipment for a dry absorption process in sulfuric acid production, in particular to an acid mixing system.
Background
The drying acid and the absorption acid adopted for drying the raw material gas and absorbing the sulfur trioxide in the sulfuric acid production are concentrated sulfuric acid with different concentrations, necessary acid mixing and process water supplement are required in the drying and absorption processes due to the requirement of system water balance, and the conventional flow of the dry acid absorption phase is that the circulating acid is uniformly mixed before a pump and is cooled after the pump to enter a tower or be produced and output so as to maintain the relatively stable concentration of the acid entering the tower and the acid produced in the drying and absorption processes. The performance of the mixed acid system determines the uniformity of mixed acid, the structure, material and process control of the mixed acid system are the key points for performance guarantee and durability use, once the mixed acid device is damaged and fails or unreasonable in configuration, the mixed acid is directly uneven, the concentration fluctuation of circulating acid is large, the drying and absorption efficiency is affected, tail pollution discharge and pollution accidents are easily caused, and meanwhile, the circulating acid pump, the circulating slot hole and the like are seriously corroded due to the sulfuric acid mist drop accumulation in the space at the top of the tank. The traditional acid mixing system is usually a sleeve type in-pipe acid mixing structure and is made of special acid-resistant alloy or steel double-sided lining polytetrafluoroethylene materials, acid liquor is boiled in a pipe and heat is concentrated due to violent reaction and large amount of heat release when acid water is mixed, a special acid-resistant alloy component still has high corrosion rate, the polytetrafluoroethylene lining structure is easy to bulge, deform and damage after being heated, the difficult problems that the acid mixing device is high in manufacturing cost, frequent in maintenance and replacement, and influences normal production operation and is short in service life exist, and the research and development of domestic and foreign sulfuric acid production enterprises on the acid mixing system in the dry absorption process are always in continuous optimization and improvement.
Disclosure of Invention
Aiming at the problems existing in the acid mixing process in the existing domestic and overseas sulfuric acid production process, the utility model aims to provide the radial injection turbulent diffusion type acid mixing system in the sulfuric acid dry absorption circulation tank, solve the problems of high manufacturing cost, short service life and non-ideal acid mixing effect of an acid mixing device, and avoid the potential safety production hazards that the production is influenced by the failure, the easy environmental pollution and the maintenance and the replacement of the acid mixing device.
The technical scheme adopted by the utility model is as follows: a mixed acid system comprises an acid-water mixer (1), an acid-acid mixer (2) and an acid inlet pipe (3); sour water mixer (1), sour acid mixer (2) inhale circulation tank body top from sulphuric acid futilely and vertically insert sulphuric acid futilely and inhale inside the circulation tank body, advance acid pipe (3) level setting and inhale the side position bottom of the oval head of one end of circulation tank body at sulphuric acid futilely, sour acid mixer (2), sour water mixer (1) are parallel arrangement in proper order along the acid feeding direction of advancing acid pipe (3), the lower extreme of sour acid mixer (2), sour water mixer (1) all is the same with the horizontal central line of advancing acid pipe (3).
Further, the acid-water mixer (1) comprises a feeding injection pipe (11), an equal-diameter tee pipe (12) and a first sleeve (13); the acid mixer (2) consists of a reducing tee pipe (21) and a second sleeve pipe (22). The feeding injection pipe (11) comprises a connecting head (111) and a central pipe (112); the connector (111) is connected with the equal-diameter three-way pipe (12) through a flange, the central pipe (112) penetrates through the equal-diameter three-way pipe (12) and the first sleeve (13) to enter the sulfuric acid dry absorption circulation tank, and the tail end of the central pipe (112) is provided with a plug (113).
Further, the lower part of the central tube (112) is provided with a plurality of layers of regularly arranged radial injection holes; the first sleeve (13) is formed by assembling an acid-resistant alloy flanging pipe (131) embedded with a polytetrafluoroethylene die-pressing flanging pipe (132); the outer diameter of the flanging ring plate is consistent with the size of a flange of a connecting pipe arranged on a sulfuric acid dry absorption circulating groove body, the flanging ring plate of the first sleeve (13) is assembled on the flange of the connecting pipe, a lower flange of an equal-diameter three-way pipe (12) molded by adopting steel lining PTFE is connected with the flange of the connecting pipe, a central pipe (112) of a feeding injection pipe (11) penetrates through the equal-diameter three-way pipe (12) and the first sleeve (13) and extends into the sulfuric acid dry absorption circulating groove, and a lower flange of a connector (111) of the feeding injection pipe (11) is assembled and connected with an upper flange of the equal-diameter three-way pipe (12).
Furthermore, the central tube (112) is a polytetrafluoroethylene die-pressed thick-wall tube, and the lower part of the central tube (112) is provided with a plurality of layers of radial injection holes which are regularly arranged; the number of the radial jet holes in each layer is three, the three jet holes in each layer are horizontally arranged, the included angle of the central lines of the three jet holes in each layer is 120 degrees, and the included angle of the central lines of the adjacent radial jet holes in two adjacent layers is 60 degrees, and the layer number and the aperture size of the radial jet holes are determined according to process calculation; the feeding medium of the central pipe (112) comprises process water supplement and dilute sulfuric acid returned by a tail gas hydrogen peroxide desulfurization system.
Furthermore, the second sleeve (22) is formed by assembling an acid-resistant alloy flanging pipe (221) with a polytetrafluoroethylene die-pressing flanging pipe (222) embedded therein, and the outer diameter sizes of flanging ring plates of the acid-resistant alloy flanging pipe (221) and the polytetrafluoroethylene die-pressing flanging pipe (222) are consistent with the size of a flange sealing surface of the connecting pipe. And a flanging ring plate of the second sleeve (22) is assembled on a flange of the connecting pipe, and a lower flange of the reducing three-way pipe (21) is connected with the flange of the connecting pipe.
Furthermore, the reducing three-way pipe (21) is a steel lining polytetrafluoroethylene die pressing pipe fitting, an upper pipe orifice of the reducing three-way pipe (21) is connected with a low-temperature heat recovery sulfuric acid pipeline, and a middle pipe orifice of the reducing three-way pipe (21) is connected with a sulfuric acid pipeline which is connected in series. The reducing tee pipe (21) is assembled with the second sleeve pipe (22) according to the acid mixing flow path requirement.
Furthermore, the lower end face of the second sleeve (22) is flush with the horizontal center line of the acid inlet pipe (3), the center line of the layer of spraying holes at the bottommost part of the central pipe (112) is flush with the horizontal center line of the acid inlet pipe (3), the distance between the lower end face of the first sleeve (13) and the horizontal center line of the layer of spraying holes at the topmost part of the central pipe (112) is 150mm, and the size of an annular gap between the outer diameter of the central pipe (112) and the inner diameter of the polytetrafluoroethylene die-pressing flanging pipe (132) is not more than 20 mm.
The utility model has the beneficial effects that:
according to the fluid turbulence diffusion principle, a novel acid mixing device is manufactured by adopting a polytetrafluoroethylene mould pressing material, acid entering from an acid inlet pipe (3) and coming out of a tower is mixed with acid entering from an acid mixer (2) in series to form transverse turbulence, and then the transverse turbulence meets a dilution reaction diffusion zone formed by radial injection process water (or dilute sulfuric acid) and vertical acid entering from an acid water mixer (1) and instantly finishes homogeneous and uniform turbulence diffusion mixing. The circulating acid which is uniformly mixed by turbulent diffusion flows to the submerged circulating pump at the rear section of the circulating tank. The acid mixing system can realize the homogeneous soaking effect of rapid mixing of acid water and acid and rapid dispersion of dilution heat and the purposes of corrosion resistance and durability, has the characteristics of uniform acid mixing, corrosion resistance and durability, convenient regulation and control, scientific and reasonable structure, advanced performance, convenient manufacture, economic material selection and low manufacturing cost, can effectively maintain the fluctuation range of the control index of the concentration of the acid entering the circulating tower to be not more than 0.1 percent, eliminates the adverse effect of the large fluctuation of the concentration of the acid entering the tower on the efficiency of the tower, has the service life of not less than 8 years, greatly saves or reduces the maintenance and replacement cost, and achieves the ideal effect of safe and stable economic operation with long production period.
Drawings
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic structural diagram of an acid-water mixer according to the present invention;
FIG. 3 is a schematic cross-sectional view of an injection hole A-A of an acid-water mixer according to the present invention;
FIG. 4 is a schematic diagram of the acid mixer of the present invention.
Detailed Description
The present invention is described in detail below with reference to examples and the accompanying drawings.
Referring to fig. 1-4, a mixed acid system includes an acid-water mixer 1, an acid-acid mixer 2, and an acid inlet pipe 3; the acid inlet pipe 3 is horizontally arranged at the bottom of the side position of the elliptic end socket at one end of the sulfuric acid dry absorption circulation tank, the acid-water mixer 1 and the acid-acid mixer 2 are vertically inserted into the sulfuric acid dry absorption circulation tank from the top of the sulfuric acid dry absorption circulation tank, the center of the bottommost layer of spray holes of the acid-water mixer 1 and the lower end face of the acid mixer 2 are both positioned on the horizontal central line of the acid inlet pipe 3, and the acid-acid mixer 2 and the acid-water mixer 1 are parallel and are sequentially arranged along the acid inlet direction of the acid inlet pipe 3.
The acid-water mixer 1 consists of a feeding injection pipe 11, an equal-diameter three-way pipe 12 and a first sleeve 13. The feeding injection pipe 11 of the acid-water mixer 1 is assembled by a flange type connector 111, a central pipe 112 and a central pipe tail end plug 113; the lower part of the central tube 112 is provided with a plurality of layers of radial injection holes which are regularly arranged, three radial injection holes on each layer are horizontally and uniformly distributed, the included angle of the central line of the holes is 120 degrees, the adjacent radial injection holes on two adjacent layers are arranged in a staggered way, the included angle is 60 degrees, and the first sleeve 13 of the acid-water mixer 1 is formed by assembling an acid-resistant alloy flanged tube 131 with a polytetrafluoroethylene die-pressing flanged tube 132 embedded therein; the outer diameter of the flanging ring plate of the acid-resistant alloy flanging pipe 131 and the polytetrafluoroethylene die-pressing flanging pipe 132 is consistent with the size of the flange of the connecting pipe arranged in the sulfuric acid dry absorption circulation tank body.
The assembly sequence of the acid-water mixer 1 is as follows: firstly, an acid-resistant alloy flanging pipe 131 of a first sleeve 13 is assembled on a flange of a connecting pipe on a sulfuric acid dry absorption circulating tank body in a socket joint mode, a polytetrafluoroethylene molded flanging pipe 132 is embedded into the acid-resistant alloy flanging pipe 131, then a lower flange of an equal-diameter three-way pipe 12 is positioned on a flanging ring plate of the polytetrafluoroethylene molded flanging pipe 132 and connected with the flange of the connecting pipe, then a feeding injection pipe 11 penetrates through the equal-diameter three-way pipe 12 and the first sleeve 13 and extends into the sulfuric acid dry absorption circulating tank body, and a lower flange of a flange type connector 111 of the feeding injection pipe 11 is connected with an upper flange of the equal-diameter three-way pipe 12 in a matched mode; the upper flange of the flange type connector 111 of the feeding injection pipe 11 is connected with a pipeline flange for process water replenishing and dilute sulfuric acid desulfurization; the middle pipe orifice flange of the equal-diameter three-way pipe 12 is connected with a sulfuric acid branch pipe flange led out by the shunting of a tower inlet acid main pipe at the outlet of the acid cooler.
The acid-acid mixer 2 consists of a reducing tee 21 and a second sleeve 22. The second sleeve 22 of the acid-acid mixer 2 is assembled by embedding a polytetrafluoroethylene molded tube 222 into an acid-resistant alloy tube 221; the outside diameter of the flanging ring plate of the acid-resistant alloy pipe 221 and the polytetrafluoroethylene molded pipe 222 is the same as the flange of the connecting pipe arranged on the sulfuric acid dry absorption circulation tank body.
The assembly sequence of the acid-acid mixer 2 is: firstly, the acid-resistant alloy flanged pipe 221 of the first sleeve 22 is assembled on a flange of a connecting pipe on a sulfuric acid dry absorption circulation tank body in a socket joint mode, then the polytetrafluoroethylene molded flanged pipe 222 is embedded into the acid-resistant alloy flanged pipe 221, and then a lower flange of the reducing three-way pipe 21 is located on a flanged ring plate of the polytetrafluoroethylene molded pipe 222 and connected with the flange of the connecting pipe; the upper flange of the reducing three-way pipe 21 is connected with a pipeline flange for recovering the low-temperature heat (the acid temperature is 120 ℃ and the acid concentration is 99.2 percent), and the middle pipe orifice flange is connected with a sulfuric acid pipeline flange for connecting the dry acid (the acid temperature is 40 ℃ and the acid concentration is 94.5 percent) or the secondary absorption acid (the acid temperature is 75 ℃ and the acid concentration is 98.3 percent) (note: the middle pipe orifice of the reducing three-way pipe 21 is connected with a sulfuric acid pipeline for connecting the secondary absorption acid in series when the acid-acid mixer 2 is used for a drying circulation tank and a sulfuric acid pipeline for connecting the dry acid in series when the secondary absorption circulation tank).
The lower end surface of the second sleeve 22 is level with the horizontal central line of the acid inlet pipe 3; the central line of a layer of water spraying holes at the bottommost part of the central pipe 112 is level with the horizontal central line of the sleeve 3 entering the tank from the tower; the lower end surface of the first sleeve 13 is 150mm away from the horizontal center line of the spraying hole on the uppermost layer of the central tube 112; the size of an annular gap between the outer diameter of the central tube 112 and the inner diameter of the polytetrafluoroethylene molded flanging tube 132 is less than or equal to 20 mm.
The pipe diameter selection and the arrangement of the injection holes related in the technical scheme are determined according to process calculation, and the sizes and the types of all components are determined according to the process condition and the structural strength calculation. This acid mixing system is according to fluid torrent diffusion principle, the play tower acid that makes the interior front end side position of dry absorption circulating groove go into the groove mixes with the cluster acid that vertical entering groove and forms horizontal torrent, then meet with radial injection technology aqueous (or dilute sulfuric acid) and the vertical dilution reaction torrent diffusion zone that advances the acid and form, and the three-dimensional torrent diffusion mixing of homogeneity soaking is accomplished to the instant, make acidic water and sour flash mixed, the heat of dilution disperses rapidly, the circulation acid flow direction through turbulent diffusion homogeneous mixing sets up the submerged circulation pump at the circulating bath rear segment.
The above is a detailed description of the utility model in connection with specific preferred embodiments, and it is not to be understood as a limitation of the utility model, and equivalent alternatives based on a radial injection turbulent diffusion type mixed acid system in a sulfuric acid dry suction circulation tank are considered to fall within the protection scope of the utility model as defined by the claims without departing from the technical line of the utility model.
Claims (11)
1. The utility model provides a mix sour system, mix sour system sets up on sulphuric acid dry absorption circulation cell body, its characterized in that: the acid mixing system comprises an acid-water mixer (1), an acid-acid mixer (2) and an acid inlet pipe (3); sour water mixer (1), sour acid mixer (2) inhale circulation tank body top from sulphuric acid futilely and vertically insert inside the sulphuric acid futilely inhales circulation tank body, advance acid pipe (3) level setting and inhale the side position bottom of the one end of circulation tank body at sulphuric acid futilely, sour acid mixer (2), sour water mixer (1) are parallel arrangement in proper order along the acid feeding direction of advancing acid pipe (3), the lower extreme of sour acid mixer (2), sour water mixer (1) all is the same with the horizontal central line of advancing acid pipe (3).
2. The mixed acid system of claim 1, wherein: the acid-water mixer (1) comprises an equal-diameter three-way pipe (12), a feeding injection pipe (11) and a first sleeve (13) connected below the equal-diameter three-way pipe (12); the feeding injection pipe (11) penetrates through the equal-diameter three-way pipe (12) and the first sleeve (13) to enter the sulfuric acid dry absorption circulating tank body, and the feeding injection pipe (11) is connected with the equal-diameter three-way pipe (12) through a flange.
3. The mixed acid system of claim 1, wherein: the acid-acid mixer (2) comprises a reducing tee pipe (21) and a second sleeve (22) connected below the reducing tee pipe (21), and the reducing tee pipe (21) is connected with the second sleeve (22) through a flange.
4. The mixed acid system of claim 2, wherein: the feeding injection pipe (11) comprises a connecting head (111) and a central pipe (112); the connector (111) is connected with the equal-diameter three-way pipe (12) through a flange, the central pipe (112) penetrates through the equal-diameter three-way pipe (12) and the first sleeve (13) to enter the sulfuric acid dry absorption circulation tank body, and the tail end of the central pipe (112) is provided with a plug (113).
5. The mixed acid system of claim 4, wherein: the lower part of the central pipe (112) is provided with a plurality of layers of radial injection holes which are regularly arranged; the radial injection holes are three in each layer, the three injection holes in each layer are horizontally distributed, the included angle of the central lines of the three injection holes in each layer is 120 degrees, and the included angle of the central lines of the adjacent radial injection holes in the two adjacent layers is 60 degrees.
6. The mixed acid system of claim 5, wherein: the lower end face of the first sleeve (13) is 150mm away from the horizontal center line of the spraying hole on the uppermost layer of the central pipe (112), and the center line of the spraying hole on the lowermost layer of the central pipe (112) is superposed with the horizontal center line of the acid inlet pipe (3).
7. The mixed acid system of claim 6, wherein: the first sleeve (13) is formed by assembling an acid-resistant alloy flanged pipe (131) embedded with a polytetrafluoroethylene molded flanged pipe (132), the acid-resistant alloy flanged pipe (131) of the first sleeve (13) is assembled on a flange of a connecting pipe on a sulfuric acid dry suction circulation tank body, and a lower flange of the equal-diameter three-way pipe (12) is connected with the flange of the connecting pipe.
8. The mixed acid system of claim 7, wherein: the size of the annular space between the outer diameter of the central tube (112) and the polytetrafluoroethylene die-pressing flanging tube (132) is less than or equal to 20 mm.
9. The mixed acid system of claim 3, wherein: the second sleeve (22) is formed by assembling an acid-resistant alloy flanging pipe (221) embedded with a polytetrafluoroethylene die-pressing flanging pipe (222), the acid-resistant alloy flanging pipe (221) of the second sleeve (22) is assembled on a flange of a connecting pipe, a lower flange of the reducing three-way pipe (21) is connected with the flange of the connecting pipe, and the lower end face of the second sleeve (22) is coincided with the horizontal central line of the acid inlet pipe (3).
10. The mixed acid system of claim 6, wherein: the feeding injection pipe (11) is made of polytetrafluoroethylene, the central pipe (112) is a thick-wall pipe, and the equal-diameter three-way pipe (12) is a steel lining polytetrafluoroethylene die-pressing pipe fitting.
11. The mixed acid system of claim 9, wherein: the reducing three-way pipe (21) is a steel lining polytetrafluoroethylene die-pressing pipe fitting, an upper pipe orifice of the reducing three-way pipe (21) is connected with a low-temperature heat recovery sulfuric acid pipeline, and a middle pipe orifice of the reducing three-way pipe (21) is connected with a sulfuric acid pipeline which is connected in series.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121987855.XU CN215901307U (en) | 2021-08-23 | 2021-08-23 | Mixed acid system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121987855.XU CN215901307U (en) | 2021-08-23 | 2021-08-23 | Mixed acid system |
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| CN215901307U true CN215901307U (en) | 2022-02-25 |
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| CN202121987855.XU Active CN215901307U (en) | 2021-08-23 | 2021-08-23 | Mixed acid system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113600045A (en) * | 2021-08-23 | 2021-11-05 | 赤峰云铜有色金属有限公司 | Mixed acid system |
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2021
- 2021-08-23 CN CN202121987855.XU patent/CN215901307U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113600045A (en) * | 2021-08-23 | 2021-11-05 | 赤峰云铜有色金属有限公司 | Mixed acid system |
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