阅读说明：本技术 一种用于铝熔体净化的氮-氯气体混合系统和方法 (Nitrogen-chlorine gas mixing system and method for aluminum melt purification ) 是由 王浩伟 汪明亮 陈哲 陈东 钟圣怡 李险峰 于 2020-06-19 设计创作，主要内容包括：本发明公开了一种用于铝熔体净化的氮-氯气体混合系统和方法,该铝熔体为铝合金熔体或铝基复合材料熔体,该系统包括：氯气源、氮气源、内置氯气检测报警装置的配气柜、置于配气柜内且内置压力检测装置的混气筒、铝熔炉、内置喷淋泵的吸收池以及包含控制模块和无线通信模块的控制装置,且混气筒经氯气管道、氮气管道和出气管道分别与氯气源、氮气源和铝熔炉连通,吸收池经一端通入其内、一端与出气管道相连的残气吹扫气管道与混气筒连通,配气柜包括单向换气扇和抽风机形成的强制换气装置和由喷淋装置且经喷淋管道与喷淋泵连接的漏气喷淋装置,通过控制装置根据设定进行远程控制实现氮-氯气体混合和安全防护,提高混合气体对铝熔体净化效率。(The invention discloses a nitrogen-chlorine gas mixing system and a method for purifying an aluminum melt, wherein the aluminum melt is an aluminum alloy melt or an aluminum-based composite material melt, and the system comprises: the gas distribution cabinet comprises a forced ventilation device formed by a one-way ventilator and an exhaust fan and a gas leakage spray device connected with the spray pump through a spray pipeline, the gas distribution cabinet comprises a nitrogen-chlorine gas mixing device and a gas leakage spray device, the nitrogen-chlorine gas mixing and safety protection are realized by the control device through remote control according to setting, and the purification efficiency of mixed gas on aluminum melt is improved.)

1. A nitrogen-chlorine gas mixing system for aluminum melt purification, comprising:

chlorine source, nitrogen gas source, built-in chlorine gas detection alarm device's distribution cabinet, arrange in the distribution cabinet and built-in pressure measurement device's gas mixing cylinder, aluminium smelting pot, built-in absorption cell that sprays the pump and contain control module and wireless communication module's controlling means, wherein:

the gas mixing cylinder is respectively communicated with the chlorine gas source, the nitrogen gas source and the aluminum smelting furnace through a chlorine gas pipeline, a nitrogen gas pipeline and a gas outlet pipeline;

The absorption pool is communicated with the gas mixing cylinder through a residual gas scavenging pipeline with one end introduced into the absorption pool and the other end connected with the gas outlet pipeline;

the distribution cabinet comprises a forced ventilation device consisting of a one-way ventilation fan which is positioned at the bottom of the distribution cabinet and can input air in a one-way mode, a suction fan which is positioned at the top of the distribution cabinet and is connected with the residual gas blowing and scavenging pipeline through a ventilation pipeline in the distribution cabinet, and a gas leakage spraying device which is positioned at the outer side of the gas mixing cylinder and is connected with the spraying pump through a spraying pipeline;

in the control device, the wireless communication module is arranged to receive and control the wireless signals sent out by the gas distribution and mixing system; the control module is set to control the gas distribution and mixing system to distribute and mix gas in the gas mixing cylinder and then output the gas to the aluminum melting furnace, sweep residual gas in the gas mixing cylinder and carry out emergency treatment on the forced ventilation device and the gas leakage spraying device according to setting.

2. The nitrogen-chlorine gas mixing system of claim 1, wherein the aluminum melt is an aluminum alloy melt or an aluminum compositeThe material combination melt contains NaOH solution or Na in the absorption tank₂CO₃Alkaline solution of the solution.

3. The nitrogen-chlorine gas mixing system of claim 1, wherein the chlorine pipe is provided with a chlorine pressure gauge, a chlorine solenoid valve and a chlorine flow meter in sequence along a chlorine flow direction, the nitrogen pipe is provided with a nitrogen pressure gauge, a nitrogen solenoid valve and a nitrogen flow meter in sequence along the chlorine flow direction, the gas outlet pipe is provided with a mixed gas outlet solenoid valve, and the control module controls the opening and flow of the chlorine gas source and the nitrogen gas source according to preset values to distribute and mix gas after the pressure in the gas mixing cylinder reaches a preset value, and the mixed gas is conveyed into the aluminum melting furnace.

4. The nitrogen-chlorine gas mixing system as set forth in claim 3, wherein the sweep gas pipe is provided with a sweep gas bypass solenoid valve, and the sweep gas pipe is connected to the gas outlet pipe at an end thereof located in front of the mixed gas outlet solenoid valve, and sweep of sweep gas in the gas mixture cylinder into the absorption tank is controlled by the control means.

5. The nitrogen-chlorine gas mixing system according to claim 1, wherein the in-cabinet air exchange pipeline is provided with an in-cabinet air exchange solenoid valve, and when the pressure detection device detects only an abnormal pressure alarm, the control device controls the one-way air exchange fan to input air into the gas distribution cabinet and simultaneously controls the exhaust fan to purge the gas in the gas distribution cabinet into the absorption cell.

6. The nitrogen-chlorine gas mixing system of claim 1, wherein the spraying pipeline is provided with a spraying solenoid valve, when the chlorine gas detection alarm device gives an alarm, the control device controls the residual gas in the gas mixing cylinder to be blown into the absorption tank, simultaneously controls the alkaline solution in the absorption tank to be sprayed into the gas distribution cabinet, and controls the exhaust fan to blow the gas in the gas distribution cabinet into the absorption tank after the spraying is finished.

7. The nitrogen-chlorine gas mixing system as recited in claim 1, wherein the gas mixing cylinder is an elongated cylindrical cylinder, and a ratio of a diameter to a length of the cylinder is not less than 1/2.

8. The nitrogen-chlorine gas mixing system according to any one of claims 1 to 6, wherein in the control device, the wireless communication module is configured to receive wireless signals sent by the chlorine gas flow meter, the nitrogen gas flow meter, the chlorine gas detection alarm device and the pressure abnormality alarm device, and perform on-off control on the chlorine gas electromagnetic valve, the nitrogen gas electromagnetic valve, the one-way ventilation fan, the in-cabinet ventilation electromagnetic valve, the exhaust fan, the mixed gas outlet electromagnetic valve, the residual gas purging bypass electromagnetic valve and the spraying electromagnetic valve;

The control module is set to start the gas distribution and mixing system to distribute and mix gas in the gas mixing cylinder according to the setting and then output the mixed gas to the aluminum melting furnace; when the primary aluminum melt purification operation is finished, residual gas in the gas mixing cylinder can be controlled to be blown and swept; when the pressure detection device gives an alarm, the forced ventilation device in the gas distribution cabinet can be started while residual gas in the gas mixing cylinder can be controlled to be blown; when the chlorine detection alarm device gives an alarm, the forced ventilation device and the air leakage spraying device in the gas distribution cabinet can be started while the residual gas in the gas mixing cylinder can be controlled to be blown.

9. A nitrogen-chlorine gas mixing method for aluminum melt purification, characterized in that the treatment is performed by the nitrogen-chlorine gas mixing system of any one of claims 1 to 8, comprising the steps of:

(1) feeding nitrogen and chlorine into a gas mixing cylinder in the gas distribution cabinet, mixing according to the setting, and feeding into an aluminum melting furnace;

(2) after the primary aluminum melt purification is finished, carrying out residual gas purging on the gas mixing cylinder by using nitrogen, sending the residual gas into an absorption tank for absorption, and then discharging the residual gas into the atmosphere;

(3) when the pressure detection device only detects that the pressure in the gas mixing cylinder is abnormal, gas distribution and gas supply are stopped, the residual gas in the step (2) is purged, the exhaust fan and the one-way exhaust fan are started to perform forced air exchange on the gas distribution cabinet, and the exchanged gas is sent into the absorption cell to be absorbed and then is discharged into the atmosphere;

(4) And (3) when the chlorine detection alarm device detects that chlorine is leaked in the gas distribution cabinet, stopping gas distribution and gas mixing and supply, conveying the alkaline solution in the absorption tank into the gas distribution cabinet for spraying through the spray pump while purging residual gas in the step (2), and carrying out forced ventilation after spraying is finished.

10. The nitrogen-chlorine gas mixing method of claim 9, wherein the steps are performed under computer control.

Technical Field

The invention belongs to the field of aluminum melt refining, and particularly relates to a nitrogen-chlorine gas mixing system and method for aluminum melt purification.

Background

The aluminum alloy melt or aluminum matrix composite melt used in the casting production process needs refining and purification. The nitrogen is introduced into the aluminum melt to obtain hydrogen-free bubbles, the bubbles can adsorb impurities when floating upwards, and the hydrogen in the aluminum melt can be absorbed into the bubbles, so that the aims of degassing and deslagging are fulfilled. Chlorine can generate strong chemical reaction with hydrogen in the aluminum melt to generate HCl and AlCl which are insoluble in the aluminum melt₃The gas has better refining and purifying effect on the aluminum melt than the nitrogen gas is singly used. However, chlorine is toxic, harmful to the human body and corrosive to equipment and the environment.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the present invention provides a nitrogen-chlorine gas mixing system for aluminum melt purification, which can safely and efficiently use nitrogen gas and chlorine gas to purify aluminum melt at the same time.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a nitrogen-chlorine gas mixing system for purifying aluminum melt, which comprises:

Chlorine source, nitrogen gas source, built-in chlorine gas detection alarm device's distribution cabinet, arrange in the distribution cabinet and built-in pressure measurement device's gas mixing cylinder, aluminium smelting pot, built-in absorption cell that sprays the pump and contain control module and wireless communication module's controlling means, wherein:

the gas mixing cylinder is respectively communicated with the chlorine gas source, the nitrogen gas source and the aluminum smelting furnace through a chlorine gas pipeline, a nitrogen gas pipeline and a gas outlet pipeline;

the absorption pool is communicated with the gas mixing cylinder through a residual gas scavenging pipeline with one end introduced into the absorption pool and the other end connected with the gas outlet pipeline;

the distribution cabinet comprises a one-way ventilating fan positioned at the bottom of the distribution cabinet and used for inputting air in a one-way mode, a forced ventilating device positioned at the top of the distribution cabinet and connected with the residual gas blowing and scavenging pipeline through a ventilating pipeline in the distribution cabinet, and a gas leakage spraying device positioned on the outer side of the gas mixing cylinder and connected with the spraying pump through a spraying pipeline;

in the control device, the wireless communication module is arranged to receive and control the wireless signals sent out by the gas distribution and mixing system; the control module is set to control the gas distribution and mixing system to distribute and mix gas in the gas mixing cylinder and then output the gas to the aluminum melting furnace, sweep residual gas in the gas mixing cylinder and carry out emergency treatment on the forced ventilation device and the gas leakage spraying device according to setting.

According to some embodiments of the invention, the aluminum melt is an aluminum alloy melt or an aluminum matrix composite melt, and the absorption cell contains NaOH solution or Na₂CO₃Alkaline solution of the solution.

According to some embodiments of the present invention, the chlorine pipeline is sequentially provided with a chlorine pressure gauge, a chlorine solenoid valve and a chlorine flow meter along a chlorine flow direction, the nitrogen pipeline is sequentially provided with a nitrogen pressure gauge, a nitrogen solenoid valve and a nitrogen flow meter along a chlorine flow direction, the gas outlet pipeline is provided with a mixed gas outlet solenoid valve, and the control module controls the opening degree and the flow rate of the chlorine source and the nitrogen source according to preset values so that gas distribution and gas mixing are performed when the pressure in the gas mixing cylinder reaches a preset value, and then the gas is conveyed to the chlorine pipeline

According to some embodiments of the present invention, a residual gas purging gas bypass solenoid valve is disposed on the residual gas purging gas pipeline, and one end of the residual gas purging gas pipeline connected to the gas outlet pipeline is located in front of the mixed gas outlet solenoid valve, and the control device controls the residual gas in the mixed gas cylinder to be purged into the absorption tank.

According to some embodiments of the present invention, the in-cabinet ventilation pipeline is provided with an in-cabinet ventilation solenoid valve, and when the pressure detection device detects only an alarm of abnormal pressure, the control device controls the exhaust fan to purge the gas in the gas distribution cabinet into the absorption tank while controlling the one-way exhaust fan to input air into the gas distribution cabinet.

According to some embodiments of the invention, the spraying pipeline is provided with a spraying electromagnetic valve, when the chlorine detection alarm device gives an alarm, the control device controls the residual gas in the gas mixing cylinder to be blown into the absorption tank, and simultaneously controls the alkaline solution in the absorption tank to be sprayed into the gas distribution cabinet, and after the spraying is finished, the exhaust fan is controlled to blow the gas in the gas distribution cabinet into the absorption tank.

According to some embodiments of the present invention, the gas mixture cylinder is an elongated cylindrical cylinder, and a ratio of a diameter of the cylinder to a length of the cylinder is not less than 1/2.

According to some embodiments of the present invention, in the control device, the wireless communication module is configured to receive wireless signals sent by the chlorine gas flowmeter, the nitrogen gas flowmeter, the chlorine gas detection alarm device, and the pressure abnormality alarm device, and perform on-off control on the chlorine gas electromagnetic valve, the nitrogen gas electromagnetic valve, the one-way ventilation fan, the in-cabinet ventilation electromagnetic valve, the exhaust fan, the mixed gas outlet electromagnetic valve, the residual gas purging bypass electromagnetic valve, and the spraying electromagnetic valve;

the control module is set to start the gas distribution and mixing system to distribute and mix gas in the gas mixing cylinder according to the setting and then output the mixed gas to the aluminum melting furnace; when the primary aluminum melt purification operation is finished, residual gas in the gas mixing cylinder can be controlled to be blown and swept; when the pressure detection device gives an alarm, the forced ventilation device in the gas distribution cabinet can be started while residual gas in the gas mixing cylinder can be controlled to be blown; when the chlorine detection alarm device gives an alarm, the forced ventilation device and the gas leakage spraying device in the gas distribution cabinet can be started while the residual gas in the gas mixing cylinder can be controlled to be blown.

The present invention also provides a nitrogen-chlorine gas mixing method for aluminum melt purification by any one of the above-described nitrogen-chlorine gas mixing systems, comprising the steps of:

(1) feeding nitrogen and chlorine into a gas mixing cylinder in the gas distribution cabinet, mixing according to the setting, and feeding into an aluminum melting furnace;

(2) after the primary aluminum melt purification is finished, carrying out residual gas purging on the gas mixing cylinder by using nitrogen, sending the residual gas into an absorption tank for absorption, and then discharging the residual gas into the atmosphere;

(3) when the pressure detection device detects that the pressure in the gas mixing cylinder is abnormal, gas distribution and gas supply are stopped, the exhaust fan and the one-way exhaust fan are started to perform forced air exchange on the gas distribution cabinet while residual gas is purged in the step (2), and the exchanged gas is sent to the absorption cell to be absorbed and then is discharged into the atmosphere;

and (3) when the chlorine gas detection alarm device detects that chlorine gas leaks from the gas distribution cabinet, stopping gas distribution and gas mixing and supply, carrying out residual gas purging in the step (2), simultaneously conveying the alkaline solution in the absorption tank into the gas distribution cabinet through the spray pump for spraying, and carrying out forced ventilation after the spraying is finished.

According to some embodiments of the nitrogen-chlorine gas mixing method of the present invention, the above steps are performed under computer control.

Compared with the prior art, the invention has the beneficial effects that:

the nitrogen-chlorine gas mixing system of the invention improves the purification efficiency of the mixed gas in the aluminum melt by mixing the chlorine gas and the nitrogen gas in the gas mixing cylinder and then conveying the mixed gas to the aluminum melt. Meanwhile, through various emergency treatment devices, possible risks and dangers in the use of the toxic gas chlorine can be reduced as much as possible, and the safety of the gas mixing system is greatly improved.

Drawings

FIG. 1 is a schematic diagram of a nitrogen-chlorine gas distribution system in accordance with a preferred embodiment of the present invention; wherein: 1. a chlorine gas source, 2, a nitrogen gas source, 3, a chlorine gas pressure gauge, 4, a nitrogen gas pressure gauge, 5, a chlorine gas electromagnetic valve, 6, a chlorine gas flowmeter, 7, a nitrogen gas electromagnetic valve, 8, a nitrogen gas flowmeter, 9, a one-way ventilating fan, 10, a spraying device, 11, a spraying electromagnetic valve, 12, a spraying pump, 13, a gas distribution cabinet, 14, a chlorine gas detection alarm device, 15, a pressure detection device, 16, a gas mixing cylinder, 17, a mixed gas outlet electromagnetic valve, 18, an aluminum melting furnace, 19, a residual gas blowing gas bypass electromagnetic valve, 20, an in-cabinet ventilating electromagnetic valve, 21, an exhaust fan, 22, an absorption pool, 24, a control module, 25, a wireless communication module, 26, a chlorine gas pipeline, 27, a nitrogen gas pipeline, 28, an in-cabinet ventilating pipeline, 29, a residual gas blowing gas pipeline, 30, an air outlet pipeline;

FIG. 2 is a schematic diagram of the gas mixing cylinder according to a preferred embodiment of the present invention;

FIG. 3 illustrates a sweep gas purge flow diagram in a preferred embodiment of the present invention;

FIG. 4 is a flow chart illustrating emergency processing when the pressure detection device alarms in a preferred embodiment of the present invention;

FIG. 5 is a flow chart showing the emergency treatment when the chlorine detecting device alarms in a preferred embodiment of the present invention.

Detailed Description

The technical contents of the preferred embodiments of the present invention will be more clearly and easily understood by referring to the drawings attached to the specification. The present invention may be embodied in many different forms of embodiments and the scope of the invention is not limited to the embodiments set forth herein.

Referring to fig. 1, which is a schematic structural diagram of a nitrogen-chlorine gas mixing system in a preferred embodiment of the present invention, a chlorine gas source 1 enters a gas distribution cabinet 13 through a chlorine gas pipeline 26 via a chlorine gas pressure gauge 3, and then enters a gas mixing cylinder 16 after passing through a chlorine gas electromagnetic valve 5 and a chlorine gas flowmeter 6 in the gas distribution cabinet 13; the nitrogen source 2 enters the gas distribution cabinet 13 through a nitrogen pipeline 27 and a nitrogen pressure gauge 4, and then enters the gas mixing cylinder 16 through the nitrogen electromagnetic valve 7 and the nitrogen flowmeter 8 in the gas distribution cabinet 13.

The flow of gas distribution and mixing is shown in fig. 3, firstly, the chlorine solenoid valve 5 and the nitrogen solenoid valve 7 are opened, after the pressure in the gas mixing cylinder 16 reaches the set range, the mixed gas outlet solenoid valve 17 is opened, the chlorine and the nitrogen are mixed in the gas mixing cylinder 16 shown in fig. 2, and the pressure detection device 15 is arranged in the mixing cylinder 16. The mixing drum 16 is an elongated drum having a ratio of drum diameter to length of not less than 1/2. Chlorine and nitrogen enter from one end of the cylinder in an up-and-down opposite-flushing mode, initial kinetic energy of airflow is fully utilized, the cylindrical cylinder enables mixing to be free of dead angles, the elongated cylinder enables the gas to move from one end to the other end in the cylinder to supply gas convection mixing time, the gas is fully mixed in the cylinder through the cylinder, then the gas is output from a mixed gas outlet at the other end of the cylinder, and the gas is sent into the aluminum melting furnace 18 through a mixed gas outlet pipeline 30 and a mixed gas outlet electromagnetic valve 17.

When the primary aluminum melt purification operation is finished, residual gas purging is required to be performed on the gas mixing cylinder 16, the residual gas purging flow is shown in fig. 3, the chlorine solenoid valve 5 and the mixed gas outlet solenoid valve 17 are closed, the residual gas purging gas bypass solenoid valve 19 on the residual gas purging gas pipeline 29 is opened, and the toxic gas chlorine in the gas mixing cylinder 16 is discharged to the alkaline NaOH solution or Na solution by using the inert gas nitrogen ₂CO₃The solution absorption tank 22 is used for discharging the harmless residual gas after chlorine gas is absorbed into the atmosphere.

When the pressure detection device 15 detects that the pressure in the gas mixing cylinder 16 abnormally drops during operation, and the chlorine detection alarm device 14 does not alarm, nitrogen possibly leaks, and the system carries out primary emergency treatment. The flow of the primary emergency treatment is shown in fig. 4. Stopping gas distribution and mixing, purging residual gas in the mixing cylinder 16, and simultaneously performing forced ventilation on the gas distribution cabinet 13: the exhaust fan 21 and the one-way ventilating fan 9 are started, the in-cabinet ventilating electromagnetic valve 20 on the in-cabinet ventilating pipeline 29 is opened at the same time, the one-way ventilating fan 9 allows outside air to enter the gas distribution cabinet 13, gas in the gas distribution cabinet 13 cannot escape through the one-way ventilating fan 9, and the exhaust fan 21 pumps the gas in the gas distribution cabinet 13 out through the in-cabinet ventilating electromagnetic valve 20 and sends the gas and residual gas scavenging gas into the absorption pool 22 together. Through the first-stage emergency treatment, the gas in the gas distribution cabinet 13 is replaced by the normal air outside, so that the related personnel can open the gas distribution cabinet 13 for manual maintenance.

When the chlorine detection alarm device 14 gives an alarm, no matter whether the pressure detection device 15 gives an alarm or not, secondary emergency treatment is started. The flow of the secondary emergency treatment is shown as the figure 5, respectively. While the residual gas is purged from the gas mixture tank 16, the spray pump 12 provided in the absorption tank 22 is started, and the spray solenoid valve 11 on the spray pipe 31 is opened to introduce the alkaline NaOH solution or Na solution in the absorption tank 22₂CO₃The solution is sprayed into the gas distribution cabinet 13 through a spraying device 10 arranged in the gas distribution cabinet 13. After the spraying is finished, forced ventilation is carried out in the gas distribution cabinet 15 so as to carry out the next manual maintenance.

The above processes can be automatically completed by the control device, the flow information sent by the chlorine flowmeter 6 and the nitrogen flowmeter 8 and the signals of the pressure detection device 15 and the chlorine detection alarm device 14 are received by the wireless communication module 25, and the electromagnetic valves, the exhaust fan 21, the one-way exhaust fan 9, the spray pump 12 and the like are remotely controlled by the control module 24.

In some embodiments, a nitrogen-chlorine gas mixing system for aluminum melt purification is provided, the system comprising a gas distribution gas mixing unit, a residual gas purging unit, a gas leakage emergency disposal unit and a central control unit, wherein:

the gas distribution and mixing unit comprises a chlorine pipeline and a nitrogen pipeline which are led into the gas distribution cabinet, wherein a chlorine electromagnetic valve and a chlorine flowmeter are arranged on the chlorine pipeline, a nitrogen electromagnetic valve and a nitrogen flowmeter are arranged on the nitrogen pipeline, the chlorine pipeline and the nitrogen pipeline are connected with a gas mixing cylinder, the gas mixing cylinder is connected with the aluminum melting furnace through a gas outlet pipeline, and a mixed gas outlet electromagnetic valve is arranged on the gas outlet pipeline;

The residual gas purging unit comprises a residual gas purging pipeline and a residual gas purging bypass valve, the residual gas purging pipeline is connected with the gas outlet pipeline and is arranged in front of the mixed gas outlet electromagnetic valve, and the residual gas purging pipeline is introduced into the absorption pool in which the alkaline solution is stored;

the emergent processing unit that leaks gas is including setting up chlorine detection alarm device in the gas distribution cabinet and setting up pressure measurement and the compulsory subunit of taking a breath and spraying the subunit in the gas mixing cylinder, wherein: the forced ventilation sub-unit comprises a one-way ventilation fan arranged on the gas distribution cabinet, an in-cabinet ventilation pipeline connected with the residual gas blowing and scavenging pipeline, an in-cabinet ventilation electromagnetic valve and a suction fan arranged on the in-cabinet ventilation pipeline; the spraying subunit comprises a spraying device arranged in the gas distribution cabinet, a spraying pipeline connected with the spraying device and communicated with the absorption tank, a spraying electromagnetic valve and a spraying pump;

the central control unit comprises a control module and a wireless communication module, the wireless communication module is set to receive wireless signals sent by the chlorine gas flowmeter, the nitrogen gas flowmeter, the chlorine gas detection alarm device and the pressure abnormity alarm device and can control the chlorine gas electromagnetic valve, the nitrogen gas electromagnetic valve, the one-way ventilation fan, the in-cabinet ventilation electromagnetic valve, the exhaust fan, the mixed gas outlet electromagnetic valve, the residual gas blowing and scavenging bypass electromagnetic valve, the spray pump and the spray electromagnetic valve; the control module is set to start the gas distribution and mixing unit to distribute and mix gas in the gas mixing cylinder according to the setting and output the mixed gas to the aluminum smelting furnace; after the primary aluminum melt purification operation is finished, the control module starts the residual gas purging unit to purge residual gas in the gas mixing cylinder; in addition, when the chlorine detection alarm device or the pressure detection device gives an alarm, the control module starts the residual gas purging unit and simultaneously starts the gas leakage emergency disposal unit.

In some embodiments of the above nitrogen-chlorine gas mixing system, when the control module starts the gas distribution and mixing unit, the control module controls the opening and flow rates of the chlorine solenoid valve and the nitrogen solenoid valve according to a preset setting so that the pressure in the gas mixing cylinder reaches a predetermined value.

In some embodiments of the above nitrogen-chlorine gas mixing system, when the control module starts the sweep gas purge unit, the control module closes the chlorine solenoid valve and the mixed gas outlet solenoid valve, opens the sweep gas bypass solenoid valve, and purges the residual chlorine gas in the mixing drum into the absorption tank by using nitrogen gas, and discharges the residual chlorine gas into the atmosphere after passing through the absorption tank.

In some embodiments of the above nitrogen-chlorine gas mixing system, when only the pressure detection device detects an abnormal pressure alarm, the control module starts the residual gas purging unit, and at the same time, only starts the forced ventilation sub-unit of the gas leakage emergency treatment unit, starts the exhaust fan and the one-way ventilation fan, opens the ventilation electromagnetic valve in the cabinet, and exchanges air outside the gas distribution cabinet into the cabinet, and sends the gas in the cabinet to the absorption pool and then discharges the air into the atmosphere.

In some embodiments of the above nitrogen-chlorine gas mixing system, when the chlorine detection alarm device gives an alarm, the control module starts the residual gas purging unit, at the same time, first starts the spraying subunit, starts the spraying pump and opens the spraying solenoid valve, and after the spraying is finished, starts the forced ventilation subunit.

In some embodiments, there is also provided a nitrogen-chlorine gas mixing method for aluminum melt purification, which is implemented by the above-described nitrogen-chlorine gas mixing unit, the method including the steps of:

(1) feeding nitrogen and chlorine into a gas mixing cylinder in a gas distribution cabinet, mixing according to a set value, and feeding into an aluminum melting furnace;

(2) after the primary aluminum melt purification is finished, residual gas in the gas mixing cylinder is blown by nitrogen, and the residual gas is sent into an absorption tank to be absorbed and then is discharged into the atmosphere;

(3) when only the pressure in the gas mixing cylinder is detected to be abnormal, gas distribution and gas supply of the gas mixing cylinder are stopped, an exhaust fan and a one-way exhaust fan which are arranged in the gas distribution cabinet are started to perform forced air exchange on the gas distribution cabinet while the step (2) is performed, and the exchanged gas is sent into an absorption cell to be absorbed and then is exhausted into the atmosphere;

(4) when detecting that chlorine gas leaks from the gas distribution cabinet, stopping gas distribution and gas mixing and feeding, and extracting alkaline solution in the absorption cell to spray in the gas distribution cabinet while performing the step (2); and (4) after spraying is finished, performing the step (3).

In some embodiments of the above nitrogen-chlorine gas mixing method, the alkaline solution is NaOH solution or Na solution₂CO₃And (3) solution.

In some embodiments of the above nitrogen-chlorine gas mixing method, the steps are performed by computer control.

In some embodiments of the above nitrogen-chlorine gas mixing method, the ratio of the diameter to the length of the gas mixture cylinder is equal to or greater than 1/2.

In some embodiments of the above nitrogen-chlorine gas mixing method, the aluminum melt is an aluminum alloy melt or an aluminum matrix composite melt.

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.