Nitrogen making machine waste gas recovery system for glass kiln

Abstract

The utility model relates to the technical field of gas separation, and aims to provide a nitrogen making machine waste gas recovery system for a glass kiln. Comprising the following steps: a compressed air preparation module leads out a pipeline which is divided into two paths, and the two paths are respectively connected to an enriched oxygen preparation module and a pure nitrogen preparation module; the oxygen-enriched preparation module comprises a membrane oxygen-enriched skid-mounted device, the oxygen-enriched outlet end of the membrane oxygen-enriched skid-mounted device is connected to the glass kiln, and the nitrogen-enriched outlet end of the membrane oxygen-enriched skid-mounted device is connected to the pure nitrogen preparation module; the pure nitrogen preparation module comprises a nitrogen making machine, the rich nitrogen outlet end of the nitrogen making machine is connected to a pure nitrogen storage tank, the waste gas outlet end of the nitrogen making machine is divided into two branches after being connected with the waste gas trapping module through a pipeline, one branch is communicated with the gas inlet of the membrane oxygen enrichment skid-mounted device, and the other branch is communicated with the rich oxygen outlet end of the membrane oxygen enrichment skid-mounted device. According to the utility model, energy waste caused by direct discharge of waste gas produced by the nitrogen making machine can be reduced through switching of serial and parallel operation modes of the oxygen-enriched preparation module, and sufficient and reasonable recycling is realized; a user can regulate and control the oxygen generation mode and flow according to actual needs, and the method is very simple and efficient.

Description

Technical Field

[0001] The utility model relates to the technical field of gas separation, in particular to an exhaust gas recovery system of a nitrogen generator for a glass kiln. Background Art

[0002] Glass kiln is a device used to melt glass and is one of the core equipment in the glass manufacturing industry. It melts glass raw materials at high temperatures, such as sand, soda ash, limestone, etc., into glass liquid, and then through processes such as molding and annealing, it is made into glass products of various shapes and specifications.

[0003] The nitrogen used in float glass furnaces has high purity requirements. It is mainly used as a protective gas for the tin bath. Its concentration requirement is generally not less than 99.5%. Pure nitrogen gas needs to be produced by equipment such as PSA nitrogen generators or cryogenic nitrogen generators.

[0004] In the prior art, the pure nitrogen gas produced by the nitrogen generator is used as the tin bath protection gas for the float glass furnace, while the low-concentration oxygen-rich gas produced by the nitrogen production process is directly discharged into the atmosphere as waste gas, resulting in a large amount of energy resources being wasted and leading to low overall energy efficiency of the entire gas production system.

[0005] Therefore, it is necessary to propose an exhaust gas recovery system in combination with the existing nitrogen generator in order to improve the overall energy efficiency and avoid energy waste caused by empty gas discharge. Utility Model Content

[0006] The technical problem to be solved by the utility model is to overcome the deficiencies in the prior art and provide an exhaust gas recovery system for a nitrogen generator for a glass kiln.

[0007] To solve the technical problem, the solution of the utility model is:

[0008] Provided is a waste gas recovery system for a nitrogen generator for a glass furnace, comprising a compressed air production module, an oxygen-enriched production module and a pure nitrogen production module; wherein:

[0009] The compressed air production module comprises an air filter, an air compressor and a dryer connected in sequence through pipelines; the end of the compressed air pipeline led out from the dryer is divided into two pipelines, namely a first compressed air branch and a second compressed air branch, the former is connected to the oxygen-enriched production module, and the latter is connected to the pure nitrogen production module;

[0010] The oxygen-enriched production module comprises a membrane oxygen-enriched skid-mounted device, which has an air inlet, an oxygen-enriched outlet and a nitrogen-enriched outlet; wherein the air inlet is connected to the first compressed air branch, the oxygen-enriched outlet is connected to the glass kiln through the oxygen-enriched pipeline, and the nitrogen-enriched outlet is connected to the second compressed air branch through the nitrogen-enriched branch;

[0011] The pure nitrogen production module includes a nitrogen generator, which has an air inlet, a nitrogen-rich outlet and a waste gas outlet; wherein the air inlet is connected to the second compressed air branch, the nitrogen-rich outlet is connected to the pure nitrogen storage tank through a nitrogen-rich pipeline, and the waste gas outlet is connected to the waste gas capture module through a waste gas pipeline; the waste gas pipeline led out from the waste gas capture module is divided into two pipelines, namely a first waste gas branch and a second waste gas branch, the former is connected to the air inlet of the membrane oxygen-enriched skid-mounted device, and the latter is connected to the oxygen-enriched outlet of the membrane oxygen-enriched skid-mounted device.

[0012] As an improved solution, regulating valves are respectively provided on the first compressed air branch, the second compressed air branch, the nitrogen-rich pipeline, the exhaust gas pipeline, the first exhaust gas branch, the second exhaust gas branch, the oxygen-rich pipeline, and the nitrogen-rich branch.

[0013] As an improved solution, a regulating valve is provided on the first compressed air branch; the end of the first exhaust gas branch is connected to the first compressed air branch, and the connection point is located between the regulating valve and the air inlet of the membrane oxygen enrichment skid-mounted device.

[0014] As an improved solution, a regulating valve is provided on the second compressed air branch, and the connection point between the nitrogen-rich branch and the second compressed air branch is located on the pipeline at the front end of the regulating valve.

[0015] As an improved solution, a regulating valve is provided on the oxygen-enriched pipeline; the end of the second exhaust gas branch is connected to the oxygen-enriched pipeline, and the connection point is located between the regulating valve and the oxygen-enriched outlet end of the membrane oxygen-enriched skid-mounted device.

[0016] As an improved solution, the nitrogen generator is a PSA nitrogen generator, which includes two adsorption towers arranged in parallel, and both towers are filled with carbon molecular sieves as adsorbents for adsorbing oxygen.

[0017] As an improved solution, the exhaust gas capture module includes a one-way valve, an exhaust gas collection network, a filter and a blower which are sequentially connected through a pipeline.

[0018] As an improved solution, a vent pipeline is provided on the exhaust gas pipeline before the exhaust gas capture module, and a vent valve is provided on the vent pipeline.

[0019] As an improved solution, a regulating valve is provided on the exhaust gas pipeline before the exhaust gas capture module, and the connection point between the venting pipeline and the exhaust gas pipeline is located at the front end of the regulating valve.

[0020] Compared with the prior art, the beneficial effects of the utility model are:

[0021] 1. In the present utility model, by using an oxygen-enriched production module that can be switched between series and parallel operation modes, it can not only reduce the energy waste caused by direct discharge of the exhaust gas produced by the nitrogen generator, but also achieve full and reasonable recycling of the exhaust gas; and the user can make a comprehensive assessment and selection according to the actual working conditions, and can selectively produce high-concentration, medium-low-concentration oxygen-enriched gas for the glass kiln, and select the appropriate concentration of oxygen-enriched gas as the combustion-supporting gas in the glass kiln. In actual use, the user only needs to control the corresponding regulating valves in the first exhaust gas branch and the second exhaust gas branch according to the actual working conditions to achieve the regulation of the oxygen production method and process, which is very simple and efficient.

[0022] 2. Regardless of the series or parallel operation mode, the nitrogen-rich gas produced by the oxygen-rich production module is connected to the second compressed air branch through the nitrogen-rich branch and mixed with compressed air to be used as the raw gas for producing pure nitrogen. Therefore, the waste caused by the empty discharge of nitrogen-rich gas can be avoided, and its energy-saving and consumption-reducing effect is very significant.

[0023] 3. After the exhaust gas produced by the nitrogen generator is processed by the exhaust gas capture device, the exhaust gas purity is improved while the exhaust gas outlet pressure is guaranteed, which not only reduces the impact of gas pressure fluctuations in the oxygen-enriched production module on the nitrogen production process, but also allows low-concentration oxygen-enriched gas to be directly used as raw gas for the production of oxygen-enriched gas or mixed with oxygen-enriched gas. Therefore, the waste caused by the empty discharge of low-concentration oxygen-enriched gas can be avoided, and its energy-saving and consumption-reducing effect is very significant.

[0024] 4. By setting a vent valve in the vent pipeline, when the one-way valve is closed and the vent valve is open, the waste gas produced by the nitrogen generator can be discharged directly from the branch line; it is convenient for users to maintain or replace accessories in the waste gas capture module in time, and the overall reliability of the equipment can be guaranteed at any time; there is no need to stop the operation of the entire system, and the operation method is flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall process of the waste gas recovery system of the nitrogen generator for the glass kiln in the utility model.

[0026] The accompanying drawings are marked as follows: 101 compressed air pipeline; 102 first compressed air branch; 103 second compressed air branch; 104 nitrogen-enriched pipeline; 105 exhaust gas pipeline; 106 first exhaust gas branch; 107 second exhaust gas branch; 108 oxygen-enriched pipeline; 109 nitrogen-enriched branch; 110 vent pipeline; 2 air filter; 3 air compressor; 4 dryer; 5 nitrogen generator; 6 membrane oxygen-enriched skid-mounted device; 7 pure nitrogen storage tank; 801-806 regulating valves; 9 glass kiln; 10 exhaust gas collection network; 11 filter; 12 blower; 13 one-way valve; 14 vent valve. DETAILED DESCRIPTION

[0027] The specific implementation of the utility model is described in detail below with reference to the accompanying drawings.

[0028] Part I. Structural Layout of the Device

[0029] The specific structure of the exhaust gas recovery system of the nitrogen generator for glass furnace is as follows: Figure 1 As shown, from the functional perspective, the device includes a compressed air production module, a pure nitrogen production module and an oxygen-enriched production module; wherein:

[0030] The compressed air production module includes an air filter 2, an air compressor 3 and a dryer 4 which are connected in sequence through pipelines. The end of the compressed air pipeline 101 led out from the dryer 4 is divided into two pipelines, namely a first compressed air branch 102 and a second compressed air branch 103. The first compressed air branch 102 and the second compressed air branch 103 are respectively provided with a regulating valve 802 and a regulating valve 801. The end of the first compressed air branch 102 is connected to the oxygen-enriched production module, and the end of the second compressed air branch 103 is connected to the pure nitrogen production module.

[0031] The oxygen-enriched production module includes a membrane oxygen-enriched skid-mounted device 6, the air inlet of the membrane oxygen-enriched skid-mounted device 6 is connected to the first compressed air branch 102, the oxygen-enriched outlet end of the membrane oxygen-enriched skid-mounted device 6 is connected to the oxygen-enriched pipeline 108, the oxygen-enriched pipeline 108 is provided with a regulating valve 806, the end of the oxygen-enriched pipeline 108 is connected to the glass kiln 9, and the nitrogen-enriched outlet end of the membrane oxygen-enriched skid-mounted device 6 is provided with a nitrogen-enriched branch 109; the nitrogen-enriched branch 109 is provided with a regulating valve 805, the end of the nitrogen-enriched branch 109 is connected to the second compressed air branch 103, and the connection point between the nitrogen-enriched branch 109 and the second compressed air branch 103 is set on the front end pipeline of the regulating valve 801;

[0032] The pure nitrogen production module includes a nitrogen generator 5, the air inlet of the nitrogen generator 5 is connected to the second compressed air branch 103, and the pure nitrogen outlet of the nitrogen generator 5 is provided with a nitrogen-enriched pipeline 104, and the nitrogen-enriched pipeline 104 is sequentially provided with a regulating valve 805 and a pure nitrogen storage tank 7. The exhaust gas outlet of the nitrogen generator 5 is connected with an exhaust gas pipeline 105, and the exhaust gas pipeline 105 is sequentially provided with a venting pipeline 110 and an exhaust gas capture module, and the venting pipeline 110 is provided with a venting valve 14. The exhaust gas capture module includes a one-way valve 13, an exhaust gas collection network 10, a filter 11 and a blower 12 connected in sequence by pipelines. The end of the exhaust gas pipeline 105 is divided into two pipelines, namely the first exhaust gas branch 106 and the second exhaust gas branch 107. The first exhaust gas branch 106 and the second exhaust gas branch 107 are respectively provided with a regulating valve 803 and a regulating valve 804. The end of the first exhaust gas branch 106 is connected to the first compressed air branch 102, and the connection point between the first exhaust gas branch 106 and the first compressed air branch 102 is set between the regulating valve 802 and the membrane oxygen enrichment skid-mounted device 6. The end of the second exhaust gas branch 107 is connected to the oxygen-enriched pipeline 108, and the connection point between the second exhaust gas branch 107 and the oxygen-enriched pipeline 108 is set between the membrane oxygen-enriched skid-mounted device 6 and the regulating valve 806.

[0033] The nitrogen generator 5 is a PSA nitrogen generator or a cryogenic nitrogen generator. For example, in the present invention, the nitrogen generator 5 is set as a PSA nitrogen generator. The PAS nitrogen generator includes two adsorption towers arranged in parallel, both towers are filled with carbon molecular sieves, which are used as adsorbents for adsorbing oxygen. By using two adsorption towers to cyclically and alternately change the pressure of each adsorption tower combined, the purpose of continuously separating the gas mixture can be achieved. Those skilled in the art can select the model of the carbon molecular sieve, the filling method and other process conditions according to the actual production situation, and the present invention does not make specific requirements.

[0034] In the utility model, each valve is used to control and shut off the airflow. The dryer 3 is mainly used to remove moisture from the compressed air, and mature technology (such as the compression heat zero gas consumption dryer on the market) can be used; the membrane oxygen enrichment skid-mounted device 4 can use commercial products on the market (such as the standard skid-mounted device module with model number ZOE12-1K). Under appropriate operating conditions, when a single standard module produces oxygen-enriched gas at a pressure of 300kPa, the oxygen-enriched concentration can reach 40%.

[0035] Part 2. Device Operation Method Description

[0036] 1. Compressed air production module:

[0037] In the compressed air production module, the air is filtered by the air filter 2 and pressurized by the air compressor 3 before flowing into the dryer 4 for dehydration. The obtained compressed air passes through the first compressed air branch 102 and the second compressed air branch 103, and enters the oxygen-enriched production module and the pure nitrogen production module respectively for gas separation process. Among them, the regulating valve 801 and the regulating valve 802 are used to switch and adjust the gas flow in the pipelines of the second compressed air branch 103 and the first compressed air branch 102.

[0038] 2. Pure nitrogen preparation module:

[0039] The compressed air flows into the nitrogen generator 5 through the second compressed air branch 103, and the nitrogen and oxygen gases are separated by the difference in the "adsorption" performance of the carbon molecular sieve to different gas molecules in the adsorption tower, and the obtained pure nitrogen gas (concentration of about 99.5) is sent to the pure nitrogen storage tank 7 through the nitrogen-enriched pipeline 104. Pure nitrogen gas can be used as a protective gas to effectively prevent the surface layer of the tin bath from being oxidized. Exemplarily, the nitrogen generator 5 includes two parallel adsorption towers, and the two towers can be automatically switched by a PLC controller to maintain the purity of the output nitrogen.

[0040] The carbon molecular sieve in the adsorption tower can be optionally filled by the snowstorm method and compacted from the top to avoid the pulverization of the carbon molecular sieve caused by the impact of high-pressure airflow, ensuring the long-term operation of the carbon molecular sieve. By adopting unequal potential equalization, the continuity of the continuous distribution of nitrogen purity from the bottom to the top of the adsorption tower bed is improved, and it is easy to quickly produce nitrogen with qualified purity, thereby improving the original purification effect and ensuring the performance indicators of the carbon molecular sieve. These are the routine operation contents of the adsorption tower, and the utility model does not make any requirements.

[0041] The low-concentration oxygen generated by the nitrogen generator 5 flows into the exhaust gas pipeline 105 as exhaust gas, and then enters the exhaust gas capture module. In the exhaust gas capture module, the exhaust gas first flows through the one-way valve 13, and then passes through the exhaust gas collection network 10 to initially filter the large particles and impurities in the exhaust gas. Then, the exhaust gas flows into the filter 10 to re-filter the impurities, water vapor, etc. in the exhaust gas to ensure the purity of the exhaust gas. The filtered exhaust gas is discharged after the blower 12 to increase the exhaust gas outlet pressure, and at the same time reduce the impact of gas pressure fluctuations in the oxygen-enriched production module on the nitrogen production process. Finally, the pressurized exhaust gas can be optionally output through the first exhaust gas branch 106 or the second exhaust gas branch 107 as a raw gas for producing oxygen-enriched gas or directly mixed with oxygen-enriched gas.

[0042] By setting up the vent pipe 110 before the exhaust gas capture module, the vent valve 14 can be opened when the one-way valve 13 is closed, so that the exhaust gas produced by the nitrogen generator can be discharged directly from the branch line, which is convenient for users to maintain the equipment in the exhaust gas capture module or replace accessories in time.

[0043] 3. The oxygen-enriched production module produces high-concentration oxygen in a series operation mode:

[0044] The waste gas produced in the pure nitrogen production module passes through the waste gas capture module and the first waste gas branch 106 in turn, and is input into the first compressed air branch 102. After being mixed with compressed air, it flows into the membrane oxygen-enriched skid-mounted device 6 as raw gas for membrane oxygen-enriched separation. At this time, the regulating valve 804 is in a closed state. When the raw gas passes through the membrane oxygen-enriched skid-mounted device 6, oxygen and nitrogen separation is achieved because oxygen is easier to permeate the membrane than nitrogen. The produced oxygen-enriched gas (with a concentration of about 40%) flows out through the oxygen-enriched pipeline 108 and is directly sent to the glass kiln 9 as a high-concentration oxygen-enriched combustion-supporting gas for the glass kiln.

[0045] The nitrogen-rich gas (with a concentration of about 90%) produced in the membrane oxygen-enriched skid-mounted device 6 is sent to the second compressed air branch 103 through the nitrogen-rich branch 109 to be mixed with the compressed air and used as the raw material gas for producing pure nitrogen.

[0046] 4. The oxygen-enriched production module produces low-concentration oxygen in parallel operation mode:

[0047] After the compressed air is separated by membrane oxygen enrichment through the membrane oxygen enrichment skid-mounted device 6, the obtained oxygen-enriched gas flows into the oxygen-enriched pipeline 108, and the obtained nitrogen-enriched gas is input into the second compressed air branch 103 through the nitrogen-enriched branch 109 to be mixed with the compressed air for use. At the same time, the waste gas produced in the pure nitrogen production module is successively input into the oxygen-enriched pipeline 108 through the waste gas capture module and the second waste gas branch 107 to be mixed with the oxygen-enriched gas for use. At this time, the regulating valve 803 is in a closed state. The oxygen-enriched gas (concentration of about 35%) obtained by directly mixing the waste gas (low-concentration oxygen-enriched gas) with the oxygen-enriched gas is used as medium- and low-concentration oxygen-enriched gas for combustion in the glass kiln.

[0048] Through the application of series and parallel switching operation of the oxygen-enriched production module, the energy waste caused by direct discharge of the exhaust gas produced by the nitrogen generator 5 can be reduced, the exhaust gas can be fully and reasonably recycled, and the comprehensive energy consumption of the gas supply system can be reduced. In addition, through the two access modes of series and parallel connection, high-concentration and medium-low-concentration oxygen-enriched gas for glass kilns can be selectively produced. Users can make a comprehensive assessment and selection based on actual working conditions and select oxygen-enriched gas of appropriate concentration as the combustion-supporting gas in the glass kiln. In actual use, users only need to control the regulating valves 803 and 804 according to the actual working conditions to adjust the method and process of oxygen production, and the operation is quick and efficient.

Claims

1. A waste gas recovery system for a nitrogen generator for a glass furnace, characterized in that: It includes compressed air production module, oxygen-enriched production module and pure nitrogen production module; among which, The compressed air production module comprises an air filter, an air compressor and a dryer connected in sequence through pipelines; the end of the compressed air pipeline led out from the dryer is divided into two pipelines, namely a first compressed air branch and a second compressed air branch, the former is connected to the oxygen-enriched production module, and the latter is connected to the pure nitrogen production module; The oxygen-enriched production module comprises a membrane oxygen-enriched skid-mounted device, which has an air inlet, an oxygen-enriched outlet and a nitrogen-enriched outlet; wherein the air inlet is connected to the first compressed air branch, the oxygen-enriched outlet is connected to the glass kiln through the oxygen-enriched pipeline, and the nitrogen-enriched outlet is connected to the second compressed air branch through the nitrogen-enriched branch; The pure nitrogen production module includes a nitrogen generator, which has an air inlet, a nitrogen-rich outlet and a waste gas outlet; wherein the air inlet is connected to the second compressed air branch, the nitrogen-rich outlet is connected to the pure nitrogen storage tank through a nitrogen-rich pipeline, and the waste gas outlet is connected to the waste gas capture module through a waste gas pipeline; the waste gas pipeline led out from the waste gas capture module is divided into two pipelines, namely a first waste gas branch and a second waste gas branch, the former is connected to the air inlet of the membrane oxygen-enriched skid-mounted device, and the latter is connected to the oxygen-enriched outlet of the membrane oxygen-enriched skid-mounted device.

2. The waste gas recovery system of the nitrogen generator for glass furnace according to claim 1, characterized in that: Regulating valves are respectively provided on the first compressed air branch, the second compressed air branch, the nitrogen-enriched pipeline, the exhaust gas pipeline, the first exhaust gas branch, the second exhaust gas branch, the oxygen-enriched pipeline, and the nitrogen-enriched branch.

3. The waste gas recovery system of the nitrogen generator for glass furnace according to claim 1, characterized in that: A regulating valve is arranged on the first compressed air branch; the end of the first exhaust gas branch is connected to the first compressed air branch, and the connection point is located between the regulating valve and the air inlet of the membrane oxygen enrichment skid-mounted device.

4. The exhaust gas recovery system for a nitrogen generator for a glass furnace according to claim 1, characterized in that: A regulating valve is arranged on the second compressed air branch, and the connection point between the nitrogen-rich branch and the second compressed air branch is located on the pipeline at the front end of the regulating valve.

5. The exhaust gas recovery system of the nitrogen generator for glass furnace according to claim 1, characterized in that: A regulating valve is arranged on the oxygen-enriched pipeline; the end of the second exhaust gas branch is connected to the oxygen-enriched pipeline, and the connection point is located between the regulating valve and the oxygen-enriched outlet end of the membrane oxygen-enriched skid-mounted device.

6. The exhaust gas recovery system of the nitrogen generator for glass furnace according to claim 1, characterized in that: The nitrogen generator is a PSA nitrogen generator, which includes two adsorption towers arranged in parallel, and both towers are filled with carbon molecular sieves as adsorbents for adsorbing oxygen.

7. The waste gas recovery system for a nitrogen generator for a glass furnace according to claim 1, characterized in that: The exhaust gas capture module includes a one-way valve, an exhaust gas collection network, a filter and a blower which are sequentially connected through pipelines.

8. The waste gas recovery system for a nitrogen generator for a glass furnace according to claim 1, characterized in that: A vent pipeline is provided on the exhaust gas pipeline before the exhaust gas capture module, and a vent valve is provided on the vent pipeline.

9. The exhaust gas recovery system of the nitrogen generator for glass furnace according to claim 8, characterized in that: A regulating valve is arranged on the exhaust gas pipeline before the exhaust gas capture module, and the connection point between the venting pipeline and the exhaust gas pipeline is located at the front end of the regulating valve.

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