阅读说明：本技术 电子级氨水制备用装置及其制备工艺 (Device for preparing electronic-grade ammonia water and preparation process thereof ) 是由 林益兴 王强 于 2021-08-23 设计创作，主要内容包括：本发明公开了一种电子级氨水制备用装置及其制备工艺,属于电子级化学品技术领域。该装置包括按气体流动方向依次连通的纯化机构、调制检测机构和制取机构,还包括连通于冷却反应釜底端处的出液循环管路,该装置在纯化机构若干第一进水管上安装的第一冷却器能将进入洗涤塔的超纯水冷却至5-10℃,在吸收塔底设置的冷却反应釜能将经吸收形成的电子级氨水初品冷却并保温在15-20℃,同时在回流浓度不合格氨水循环段上设置的第二冷却器能将重新进入吸收塔的不合格电子级氨水冷却至5-10℃,上述装置和工艺能够有效降低因温度过高导致杂气或氨气重新挥发引起的成品纯度不够或浓度不足的情况。(The invention discloses a device for preparing electronic-grade ammonia water and a preparation process thereof, and belongs to the technical field of electronic-grade chemicals. The device comprises a purification mechanism, a modulation detection mechanism and a preparation mechanism which are sequentially communicated according to the gas flow direction, and further comprises a liquid outlet circulation pipeline communicated with the bottom end of a cooling reaction kettle, wherein a first cooler arranged on a plurality of first water inlet pipes of the purification mechanism can cool ultrapure water entering a washing tower to 5-10 ℃, the cooling reaction kettle arranged at the bottom of an absorption tower can cool an electronic-grade ammonia water primary product formed by absorption and keep the temperature at 15-20 ℃, meanwhile, a second cooler arranged on an ammonia water circulation section with unqualified reflux concentration can cool unqualified electronic-grade ammonia water entering the absorption tower again to 5-10 ℃, and the device and the process can effectively reduce the condition that the purity of a finished product is insufficient or the concentration is insufficient due to the fact that miscellaneous gas or ammonia gas is volatilized again caused by overhigh temperature.)

1. The utility model provides an electron level aqueous ammonia preparation facilities which characterized in that: comprises a purification mechanism (1), a modulation detection mechanism (2) and a preparation mechanism (3) which are sequentially communicated and arranged according to the gas flowing direction;

the purification mechanism (1) comprises a washing tower (11), the bottom end of the washing tower is provided with an air inlet end, and the air inlet end is communicated with a first air inlet pipe (12); a plurality of water inlet ends are arranged above the air inlet end on the washing tower, each water inlet end is communicated with a first water inlet pipe (13), and each first water inlet pipe is connected with a first cooler (131) in series;

prepare mechanism (3) and locate cooling reaction kettle (32) of this absorption tower bottom including an absorption tower (31) and location, the top and a second inlet tube (33) intercommunication of absorption tower, the bottom of absorption tower is passed through modulation detection mechanism (2) with the gas outlet intercommunication on scrubbing tower (11) top, cooling reaction kettle's bottom is equipped with out liquid circulation pipeline (4), and a second cooler (46) has concatenated in the location on this circulation section that goes out liquid circulation pipeline, and this play liquid circulation pipeline's play liquid section and external stock solution device intercommunication.

2. The electronic grade ammonia water preparation device according to claim 1, characterized in that: the modulation detection mechanism (2) comprises a gas pipe (21) communicated between a gas outlet at the top end of the washing tower and a gas inlet at the bottom end of the absorption tower, and a dryer (22), a humidity sensor (26) for detecting the humidity of the gas, a gas purity detector (23) and a second flow controller (25) for controlling the flow of the gas are sequentially connected in series on the gas pipe along the flow direction of the gas.

3. The electronic grade ammonia water preparation device according to claim 2, characterized in that: the modulation detection mechanism (2) further comprises a buffer tank (24) which is connected in parallel with the gas transmission pipe (21) between the gas purity detector and the second flow controller through a gas transmission pipe branch pipe, and the bottom end of the buffer tank is communicated with the gas inlet end at the bottom end of the washing tower (11) through a return gas pipe (241).

4. The electronic grade ammonia water preparation device according to claim 3, characterized in that: a first electromagnetic three-way valve (242) is positioned at the joint of the gas conveying pipe branch pipe at the gas inlet of the buffer tank (24) and the gas conveying pipe.

5. The electronic grade ammonia water preparation device according to claim 1, characterized in that: the liquid outlet circulation pipeline (4) comprises a liquid conveying pipe (41) communicated between a liquid outlet at the bottom end of the cooling reaction kettle (32) and a liquid inlet at the top end of the absorption tower (31), and a second diaphragm pump (42), a filter (43) for filtering impurities and a liquid detector (44) for detecting liquid concentration are sequentially connected onto the liquid conveying pipe in series along the liquid flowing direction.

6. The electronic grade ammonia water preparation device according to claim 5, characterized in that: the second cooler (46) is connected in series on the infusion tube (41) close to the absorption tower (31), an output tube (45) communicated with the infusion tube is formed on the infusion tube between the second cooler and the liquid detector (44), and the tail end of the output tube is communicated with an external liquid storage device; and a second electromagnetic three-way valve (47) is positioned at the intersection joint of the output pipe (45) and the infusion pipe (41).

7. The electronic grade ammonia water preparation device according to claim 1, characterized in that: the bottom end of the washing tower (11) is provided with a waste water discharge end, and a first diaphragm pump (14) capable of pumping waste water to discharge is positioned on the waste water discharge end; a tail gas exhaust pipe (35) for exhausting waste gas is arranged at the top end of the absorption tower (31); the first air inlet pipe (12) is connected with a first flow controller (121) in series in a positioning mode.

8. A preparation process of electronic-grade ammonia water, which is carried out by using the device of any one of claims 1 to 7, and is characterized by mainly comprising the following steps:

s1, purification: high-purity ammonia gas is conveyed into the washing tower from the bottom of the washing tower through a first gas inlet pipe under the control of a first flow controller, ultrapure water is cooled by a plurality of first coolers and then enters the top of the washing tower through a first water inlet pipe, the high-purity ammonia gas and the ultrapure water are in reverse contact, impurity gases are removed through washing to obtain ultrapure ammonia gas, and waste liquid generated by washing is pumped and discharged through a first diaphragm pump;

s2, modulation: the method comprises the following steps that ultrapure ammonia gas is conveyed along a gas conveying pipe, is dried by a dryer, is subjected to humidity detection by a humidity sensor and is detected by a gas purity detector in sequence, the ultrapure ammonia gas with qualified detection indexes is conveyed along the gas conveying pipe by a first electromagnetic three-way valve and enters the bottom of an absorption tower after the flow is controlled by a second flow controller, and the ultrapure ammonia gas with unqualified detection indexes enters a buffer tank by a first electromagnetic three-way valve and then flows back into a washing tower through a backflow gas pipe for re-washing;

s3, preparing: the ultra-pure ammonia gas with qualified detection indexes enters the absorption tower from the bottom of the absorption tower, a second water inlet pipe at the top of the ultra-pure ammonia gas self-absorption tower enters a distributor at the top of the absorption tower and sprays downwards, the ultra-pure ammonia gas and the ultra-pure water reversely contact and are absorbed in a filler area to form an electronic-grade ammonia water primary product, the electronic-grade ammonia water primary product is dripped into a cooling reaction kettle, the electronic-grade ammonia water primary product is cooled in the cooling reaction kettle and then discharged, and tail gas is discharged through a tail gas exhaust pipe at the top of the absorption tower;

s4, detecting backflow: and conveying the primary electronic-grade ammonia water discharged from the self-cooling reaction kettle into a filter under the pumping of a second diaphragm pump to filter to obtain electronic-grade ammonia water, allowing the electronic-grade ammonia water to enter a liquid detector to detect the impurity concentration in the electronic-grade ammonia water, discharging and collecting qualified electronic-grade ammonia water with qualified detection indexes through an output pipe, cooling the unqualified qualified electronic-grade ammonia water through a second cooler, and conveying the unqualified electronic-grade ammonia water back into an absorption tower to prepare again.

9. The process for preparing electronic grade ammonia water according to claim 8, wherein: and the ultrapure water in the step S1 is cooled to 5-10 ℃ by a first cooler.

10. The process for preparing electronic grade ammonia water according to claim 8, wherein: in the step S3, the temperature of the electronic-grade ammonia water primary product is reduced to 20-30 ℃ in the cooling reaction kettle and is kept at the temperature all the time; and cooling the unqualified electronic-grade ammonia water in the step S4 to 5-10 ℃ through a second cooler.

Technical Field

The invention relates to a device for preparing electronic-grade ammonia water and a preparation process thereof, and belongs to the technical field of electronic-grade chemical production.

Background

In the semiconductor industry, the electrical resistivity of a pure semiconductor product is greatly changed by doping a trace amount of impurity elements into the product. Thus, the semiconductor industry has very high demands on the purity of the chemical materials used therein, and typically uses electronic grade chemicals.

Electronic-grade ammonia water is one of eight electronic-grade chemical materials commonly used in the semiconductor industry, the consumption of the electronic-grade ammonia water is the third in the electronic product industry, the electronic-grade ammonia water is mainly used for diffusion, corrosion, cleaning and other processes of silicon wafers, and the electronic-grade ammonia water can activate the surfaces of silicon wafers and particles by utilizing the weak alkalinity of the ammonia water and can remove surface particles and partial metal impurities of the silicon wafers and the particles. Therefore, electronic-grade ammonia water is widely used for cleaning chips.

The production process of the electronic grade ammonia water mainly comprises an intermittent rectification method, a membrane filtration absorption method, a resin filtration method and the like. The above-mentioned production processes are diversified, but most of them include evaporation, purification, and absorption processes, in which liquid ammonia is pressure-fed from a raw material tank into an evaporator by a compressor, and evaporated into ammonia gas by hot vapor in the evaporator; then the vaporized ammonia gas passes through a drainage separator and an activated carbon adsorber in turn to obtain purified ammonia gas; adsorbing and deoiling the purified and filtered ammonia gas by using adsorption resin, and washing and removing impurities by using ultrapure water and saturated ammonia water; separating the treated ammonia gas into water gas and ammonia gas by a water-gas separator, absorbing the separated ammonia gas by ultrapure water in an absorption tower, and performing ultrafiltration to obtain electronic-grade ammonia water.

Preparation facilities and preparation technology that use among the prior art are in washing edulcoration and absorption stage, can release the heat when ammonia contacts with ultrapure water or saturated aqueous ammonia to the temperature that leads to in scrubbing tower and the absorption tower is higher, especially can make the temperature in the scrubbing tower higher, thereby make the impure gas in the scrubbing tower bottom solution volatilize again easily, this impure gas can be mixed with the ultrapure ammonia that obtains through the washing, make the ammonia purity of scrubbing tower output reduce, and then influence the preparation of follow-up electronic level aqueous ammonia.

Disclosure of Invention

In order to solve the technical problems, the invention provides a device for preparing electronic-grade ammonia water and a preparation process thereof, and the device and the process can avoid the problem that the purity of the electronic-grade ammonia water is influenced because miscellaneous gas removed by washing is re-volatilized at a higher temperature and is mixed with ultrapure ammonia gas.

The technical scheme of the invention is as follows:

an electronic-grade ammonia water preparation device comprises a purification mechanism, a modulation detection mechanism and a preparation mechanism which are sequentially communicated and arranged according to a gas flowing direction;

the purification mechanism comprises a washing tower, the bottom end of the washing tower is provided with an air inlet end, and the air inlet end is communicated with a first air inlet pipe; a plurality of water inlet ends are arranged above the air inlet end on the washing tower, each water inlet end is communicated with a first water inlet pipe, and a first cooler is connected to each first water inlet pipe in series;

the preparation mechanism comprises an absorption tower and a cooling reaction kettle which is positioned at the bottom end of the absorption tower, the top end of the absorption tower is communicated with a second water inlet pipe, the bottom end of the absorption tower is communicated with a gas outlet at the top end of the washing tower through the modulation detection mechanism, a liquid outlet circulation pipeline is arranged at the bottom end of the cooling reaction kettle, a second cooler is connected in series at the circulation section of the liquid outlet circulation pipeline in a positioning mode, and the liquid outlet section of the liquid outlet circulation pipeline is communicated with an external liquid storage device.

The further technical scheme is as follows:

the modulation detection mechanism comprises a gas pipe communicated between a gas outlet at the top end of the washing tower and a gas inlet at the bottom end of the absorption tower, and a dryer, a humidity sensor for detecting the humidity of gas, a gas purity detector and a second flow controller for controlling the flow of the gas are sequentially connected in series on the gas pipe along the gas flowing direction.

The further technical scheme is as follows:

the modulation detection mechanism further comprises a buffer tank which is connected in parallel with the gas pipe between the gas purity detector and the second flow controller through a gas pipe branch pipe, and the bottom end of the buffer tank is communicated with the gas inlet end at the bottom end of the washing tower through a reflux gas pipe.

The further technical scheme is as follows:

and a first electromagnetic three-way valve is positioned at the joint of the gas pipe branch pipe at the gas inlet of the buffer tank and the gas pipe.

The further technical scheme is as follows:

the liquid outlet circulation pipeline comprises a liquid conveying pipe communicated between a liquid outlet at the bottom end of the cooling reaction kettle and a liquid inlet at the top end of the absorption tower, and a second diaphragm pump, a filter for filtering impurities and a liquid detector for detecting liquid concentration are sequentially connected in series on the liquid conveying pipe along the liquid flowing direction.

The further technical scheme is as follows:

the second cooler is connected in series on the liquid conveying pipe close to the absorption tower, an output pipe communicated with the liquid conveying pipe is formed on the liquid conveying pipe between the second cooler and the liquid detector, and the tail end of the output pipe is communicated with an external liquid storage device; and a second electromagnetic three-way valve is positioned at the intersection of the output pipe and the infusion pipe.

The further technical scheme is as follows:

the bottom end of the washing tower is provided with a wastewater discharge end, and a first diaphragm pump capable of pumping wastewater to discharge is positioned on the wastewater discharge end; a tail gas exhaust pipe for discharging waste gas is arranged at the top end of the absorption tower; and a first flow controller is positioned and connected in series on the first air inlet pipe.

The invention also discloses a preparation process of the electronic-grade ammonia water, which is carried out by using the device and mainly comprises the following steps:

s1, purification: high-purity ammonia gas is conveyed into the washing tower from the bottom of the washing tower through a first gas inlet pipe under the control of a first flow controller, ultrapure water is cooled by a plurality of first coolers and then enters the top of the washing tower through a first water inlet pipe, the high-purity ammonia gas and the ultrapure water are in reverse contact, impurity gases are removed through washing to obtain ultrapure ammonia gas, and waste liquid generated by washing is pumped and discharged through a first diaphragm pump;

s2, modulation: the method comprises the following steps that ultrapure ammonia gas is conveyed along a gas conveying pipe, is dried by a dryer, is subjected to humidity detection by a humidity sensor and is detected by a gas purity detector in sequence, the ultrapure ammonia gas with qualified detection indexes is conveyed along the gas conveying pipe by a first electromagnetic three-way valve and enters the bottom of an absorption tower after the flow is controlled by a second flow controller, and the ultrapure ammonia gas with unqualified detection indexes enters a buffer tank by a first electromagnetic three-way valve and then flows back into a washing tower through a backflow gas pipe for re-washing;

s3, preparing: the ultra-pure ammonia gas with qualified detection indexes enters the absorption tower from the bottom of the absorption tower, a second water inlet pipe at the top of the ultra-pure ammonia gas self-absorption tower enters a distributor at the top of the absorption tower and sprays downwards, the ultra-pure ammonia gas and the ultra-pure water reversely contact and are absorbed in a filler area to form an electronic-grade ammonia water primary product, the electronic-grade ammonia water primary product is dripped into a cooling reaction kettle, the electronic-grade ammonia water primary product is cooled in the cooling reaction kettle and then discharged, and tail gas is discharged through a tail gas exhaust pipe at the top of the absorption tower;

s4, detecting backflow: and conveying the primary electronic-grade ammonia water discharged from the self-cooling reaction kettle into a filter under the pumping of a second diaphragm pump to filter to obtain electronic-grade ammonia water, allowing the electronic-grade ammonia water to enter a liquid detector to detect the impurity concentration in the electronic-grade ammonia water, discharging and collecting qualified electronic-grade ammonia water with qualified detection indexes through an output pipe, cooling the unqualified qualified electronic-grade ammonia water through a second cooler, and conveying the unqualified electronic-grade ammonia water back into an absorption tower to prepare again.

The further technical scheme is as follows:

and the ultrapure water in the step S1 is cooled to 5-10 ℃ by a first cooler.

The further technical scheme is as follows:

in the step S3, the temperature of the electronic-grade ammonia water primary product is reduced to 20-30 ℃ in the cooling reaction kettle and is kept at the temperature all the time; and cooling the unqualified electronic-grade ammonia water in the step S4 to 5-10 ℃ through a second cooler.

The beneficial technical effects of the invention are as follows:

1. this application device and technology carry the bottom to the scrubbing tower with high-purity ammonia via first intake pipe, ultrapure water carries to each height of scrubbing tower after cooling to the uniform temperature at the first cooler on a plurality of first inlet tubes, high-purity ammonia and the cooling ultrapure water reverse contact to the uniform temperature, can make the inside temperature of scrubbing tower be in lower state all the time in the ammonia washing process, thereby can effectively avoid making the condition that miscellaneous gas volatilizees again wherein because of the waste liquid temperature is higher after the washing, can guarantee that the ammonia through the washing is ultrapure ammonia.

2. The modulation detection mechanism is provided with the buffer tank, so that unqualified gas can be temporarily stored and buffered and then flows back to the washing tower for circular purification again, and the utilization rate of raw materials and the purity of a final finished product can be improved;

3. this application device and technology are provided with cooling reation kettle in the bottom of absorption tower, and the preliminary product of electron level aqueous ammonia that forms through the absorption reaction precools in this cooling reation kettle, can reduce the heat that water and ammonia absorption reaction produced in the absorption tower to reduce the temperature of the preliminary product of electron level aqueous ammonia, carry out the precooling for the preliminary product of electron level aqueous ammonia that follow-up needs backward flow simultaneously.

4. This application sets up cooling device on the backward flow route of the electronic grade aqueous ammonia primary product of backward flow, carries out further cooling to the electronic grade aqueous ammonia primary product that needs the backward flow, can make the reflux solution that contacts with ultrapure ammonia be in lower temperature when reacting with ultrapure ammonia absorption, and the temperature of the final product electronic grade aqueous ammonia of avoiding forming is higher.

Drawings

FIG. 1 is a schematic view of the overall structure of the apparatus of the present invention;

wherein:

1. a purification mechanism; 11. a washing tower; 12. a first intake pipe; 121. a first flow controller; 13. a first water inlet pipe; 131. a first cooler; 14. a first diaphragm pump;

2. a modulation detection mechanism; 21. a gas delivery pipe; 22. a dryer; 23. a gas purity detector; 24. a buffer tank; 241. a reflux gas pipe; 242. a first electromagnetic three-way valve; 25. a second flow controller; 26. a humidity sensor;

3. a preparation mechanism; 31. an absorption tower; 32. cooling the reaction kettle; 33. a second water inlet pipe; 34. a liquid level meter; 35. a tail gas exhaust pipe;

4. a liquid outlet circulation pipeline; 41. a transfusion tube; 42. a second diaphragm pump; 43. a filter; 44. a liquid detector; 45. an output pipe; 46. a second cooler; 47. and a second electromagnetic three-way valve.

Detailed Description

In order to make the technical means of the present invention clearer and to make the technical means of the present invention capable of being implemented according to the content of the specification, the following detailed description of the embodiments of the present invention is made with reference to the accompanying drawings and examples, which are provided for illustrating the present invention and are not intended to limit the scope of the present invention.

The embodiment describes an electronic-grade ammonia water preparation device in detail, and the preparation device comprises a purification mechanism 1, a modulation detection mechanism 2, a preparation mechanism 3 and a liquid outlet circulation pipeline 4 which are sequentially communicated and arranged according to the gas flowing direction.

The purifying mechanism 1 comprises a washing tower 11, an air inlet end is arranged at the bottom end of the washing tower, the air inlet end is communicated with a first air inlet pipe 12, and a first flow controller 121 is positioned and connected in series on the first air inlet pipe 12. The washing tower is provided with a plurality of water inlet ends above the air inlet end, and specifically, the plurality of water inlet ends are uniformly distributed at intervals along the height of the washing tower above the air inlet end and also can be spirally distributed at intervals along the height of the washing tower in a staggered manner in the circumferential direction of the washing tower. Every inlet end department all communicates with a first inlet tube 13, and all has concatenated first cooler 131 on every first inlet tube, and wherein the inner of first inlet tube extends to the inside of scrubbing tower, and the inner of a plurality of first inlet tubes on the radial surface of scrubbing tower length difference and be the staggered arrangement cloth, can guarantee like this that the play water of first inlet tube can lay in whole scrubbing tower. The bottom of scrubbing tower 11 is equipped with the waste water discharge end, and this waste water discharge end goes up the location and is equipped with a first diaphragm pump 14 that can extract waste water and carry out the emission, extracts the waste water that the scrubbing tower is located the bottom through this first diaphragm pump, and waste water discharge accelerates, can prevent that volatile miscellaneous gas in the waste water from getting into inside the scrubbing tower.

The modulation detection mechanism 2 comprises a gas pipe 21 communicated between an air outlet at the top end of the washing tower 11 and an air inlet at the bottom end of the absorption tower 31, and a dryer 22, a humidity sensor 26 for detecting the humidity of the gas, a gas purity detector 23 and a second flow controller 25 for controlling the flow of the gas are sequentially connected in series on the gas pipe along the gas flowing direction. The modulation detection mechanism 2 further comprises a buffer tank 24 connected in parallel to the gas pipe 21 between the gas purity detector 23 and the second flow controller 25 through a gas pipe branch pipe, the bottom end of the buffer tank is communicated with the gas inlet end at the bottom end of the washing tower 11 through a return gas pipe 241, and a first electromagnetic three-way valve 242 is positioned at the joint of the gas pipe branch pipe at the gas inlet of the buffer tank 24 and the gas pipe. When the device is used, ultrapure ammonia in the washing tower is conveyed through the gas conveying pipe 21, is dried through the dryer, and then is subjected to humidity detection through the humidity sensor and purity detection through the gas purity detector in sequence, the ultrapure ammonia with qualified detection indexes is conveyed along the gas conveying pipe through the first electromagnetic three-way valve and enters the bottom of the absorption tower after the flow is controlled through the second flow controller, and the ultrapure ammonia with unqualified detection indexes enters the buffer tank through the first electromagnetic three-way valve and then flows back into the washing tower through the backflow gas pipe for re-washing.

The preparation mechanism 3 comprises an absorption tower 31 and a cooling reaction kettle 32 positioned at the bottom end of the absorption tower, the top end of the absorption tower is communicated with a second water inlet pipe 33, and the bottom end of the absorption tower is communicated with the air outlet at the top end of the washing tower 11 through the modulation detection mechanism 2. The bottom end of the cooling reaction kettle is provided with a liquid outlet circulation pipeline 4, a second cooler 46 is positioned and connected in series on the circulation section of the liquid outlet circulation pipeline, and the liquid outlet section of the liquid outlet circulation pipeline is communicated with an external liquid storage device. In addition, a tail gas exhaust pipe 35 for exhausting waste gas is provided at the top end of the absorption tower 31, and the excess waste gas in the absorption tower is exhausted through the tail gas exhaust pipe, so that the balance of the air pressure in the absorption tower can be maintained. And, a level gauge 34 communicated with the inside of the cooling reaction kettle is positioned and installed on the outer wall of the cooling reaction kettle 32, and the height position of the liquid in the cooling reaction kettle is detected through the level gauge.

The liquid outlet circulation pipeline 4 comprises a liquid conveying pipe 41 communicated between a liquid outlet at the bottom end of the cooling reaction kettle 32 and a liquid inlet at the top end of the absorption tower 31, a second diaphragm pump 42, a filter 43 for filtering impurities and a liquid detector 44 for detecting liquid concentration are sequentially connected in series on the liquid conveying pipe along the liquid flowing direction, and the electronic-grade ammonia water primary product is conveyed into the filter through the second diaphragm pump for filtering so as to further remove the impurities in the electronic-grade ammonia water primary product, thereby improving the purity of finished products. The infusion tube 41 is provided with the second cooler 46 in series close to the absorption tower 31, and the second cooler can cool down the filtered electronic-grade ammonia water with substandard concentration so as to be conveyed into the absorption tower again to be used as absorption liquid, thereby preventing the electronic-grade ammonia water with substandard concentration from further reducing the concentration due to higher volatilization of temperature. An output pipe 45 communicated with the liquid conveying pipe 41 is formed on the liquid conveying pipe between the second cooler 46 and the liquid detector 44, the output pipe section forms a liquid outlet section of the liquid outlet circulation pipeline 4, and the tail end of the output pipe is communicated with an external liquid storage device; the liquid transfer line 41 is located between the outlet line 45 and the liquid inlet of the absorption column to constitute a circulation section of the liquid outlet circulation line 4, and the second cooler 46 is located at the section. In addition, a second electromagnetic three-way valve 47 is positioned at the intersection of the output pipe 45 and the liquid conveying pipe 41, when the electronic-grade ammonia water is detected by the liquid detector for the impurity concentration therein, the electronic-grade ammonia water which is qualified in detection is discharged and collected through the output pipe, and the unqualified electronic-grade ammonia water which is unqualified in detection index is cooled by the second cooler and then conveyed back to the absorption tower for re-preparation.

The embodiment further describes in detail a preparation process of electronic grade ammonia water, which is performed by using the device and mainly comprises the following steps:

s1, purification: high-purity ammonia gas is conveyed into the washing tower from the bottom of the washing tower through a first gas inlet pipe under the control of a first flow controller, ultrapure water is cooled by a plurality of first coolers and then enters the top of the washing tower through a first water inlet pipe, the high-purity ammonia gas and the ultrapure water are in reverse contact, impurity gases are removed through washing to obtain ultrapure ammonia gas, and waste liquid generated by washing is pumped and discharged through a first diaphragm pump; wherein the ultrapure water is cooled to 5-10 ℃ by a first cooler.

S2, modulation: the method comprises the following steps that ultrapure ammonia gas is conveyed along a gas conveying pipe, is dried through a dryer, is subjected to humidity detection through a humidity sensor and purity detection through a gas purity detector in sequence, the ultrapure ammonia gas with qualified detection indexes is conveyed along the gas conveying pipe through a first electromagnetic three-way valve and enters the bottom of an absorption tower after the flow is controlled through a second flow controller, and the ultrapure ammonia gas with unqualified detection indexes enters a buffer tank through the first electromagnetic three-way valve and then flows back into a washing tower through a backflow gas pipe to be washed again.

S3, preparing: the ultra-pure ammonia gas with qualified detection indexes enters the absorption tower from the bottom of the absorption tower, a second water inlet pipe at the top of the ultra-pure ammonia gas self-absorption tower enters a distributor at the top of the absorption tower and sprays downwards, the ultra-pure ammonia gas and the ultra-pure water reversely contact and are absorbed in a filler area to form an electronic-grade ammonia water primary product, the electronic-grade ammonia water primary product is dripped into a cooling reaction kettle, the electronic-grade ammonia water primary product is cooled in the cooling reaction kettle and then discharged, and tail gas is discharged through a tail gas exhaust pipe at the top of the absorption tower; wherein the temperature of the electronic grade ammonia water primary product is reduced to 20-30 ℃ in the cooling reaction kettle and is always kept at the temperature.

S4, detecting backflow: conveying the primary electronic-grade ammonia water discharged from the self-cooling reaction kettle into a filter under the pumping action of a second diaphragm pump for filtering to obtain electronic-grade ammonia water, allowing the electronic-grade ammonia water to enter a liquid detector for detecting the concentration of impurities in the electronic-grade ammonia water, discharging and collecting qualified electronic-grade ammonia water with qualified detection indexes through an output pipe, cooling and cooling the unqualified electronic-grade ammonia water with unqualified detection indexes through a second cooler, and conveying the unqualified electronic-grade ammonia water back into an absorption tower for re-preparation; wherein the unqualified electronic-grade ammonia water is cooled to 5-10 ℃ by a second cooler.

This application device and technology carry the bottom to the scrubbing tower with high-purity ammonia via first intake pipe, ultrapure water carries to each height of scrubbing tower after cooling to the uniform temperature at the first cooler on a plurality of first inlet tubes, high-purity ammonia and the cooling ultrapure water reverse contact to the uniform temperature, can make the inside temperature of scrubbing tower be in lower state all the time in the ammonia washing process, thereby can effectively avoid making the condition that miscellaneous gas volatilizees again wherein because of the waste liquid temperature is higher after the washing, can guarantee that the ammonia through the washing is ultrapure ammonia. Secondly, this application is provided with the buffer tank in modulation detection mechanism department, and it can circulate purification once more in the scrubbing tower with backward flow after unqualified gas buffers of keeping in, can improve the utilization ratio of raw materials and the purity of final finished product. Furthermore, this application is provided with cooling reation kettle in the bottom of absorption tower, and the preliminary product of electron level aqueous ammonia that forms through the absorption reaction precools in this cooling reation kettle, can reduce the heat that water and ammonia absorption reaction produced in the absorption tower to reduce the temperature of the preliminary product of electron level aqueous ammonia, carry out the precooling for the preliminary product of electron level aqueous ammonia that follow-up needs backward flow simultaneously. Finally, this application sets up cooling device on the backward flow route of the electronic grade aqueous ammonia primary product of backward flow, carries out further cooling to the electronic grade aqueous ammonia primary product that needs the backward flow, can make the reflux solution that contacts with ultrapure ammonia be in lower temperature when reacting with ultrapure ammonia absorption, avoids the temperature of the final product electronic grade aqueous ammonia that forms higher.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, it should be noted that, for those skilled in the art, many modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.