Emergency device for float glass flue gas treatment

Abstract

The utility model provides an emergency device for float glass flue gas treatment, which comprises a standby flue gas treatment system, the standby flue gas treatment system can be used for replacing a main system with a plurality of production lines, and the production lines share one connection flue to be connected with the standby flue gas treatment system. The standby flue gas treatment system is divided into a waste heat recovery section and a flue gas treatment section; the standby flue gas treatment system comprises a main flue and a bypass flue; the main flue is connected to the waste heat recovery section through the connection flue, so that flue gas is subjected to waste heat recovery and then enters the SCR denitration system of the flue gas treatment section to form a main flue line; the bypass flue is directly connected to the flue gas treatment section through the connection flue, so that flue gas enters the SCR denitration system firstly and then is subjected to waste heat recovery to form a bypass flue line; and the standby flue gas treatment system can be switched between a main flue line and a bypass flue line.

Description

Technical Field

[0001] The utility model relates to the field of float glass production technology, in particular to an emergency device for treating float glass smoke. Background Art

[0002] As of the beginning of 2023, there are nearly 300 float glass production lines of different tonnages in China, which have contributed to the supply of glass materials for the Chinese construction market. However, float glass production is a high-energy-consuming and high-pollution industry. A large amount of sulfur dioxide, nitrogen oxides and dust particles remain in the exhaust gas of the melting furnace, which endangers our living environment. Therefore, the state requires the establishment of environmental protection measures such as desulfurization, denitrification and dust removal of melting furnace flue gas, to achieve real-time monitoring of environmental protection indicators, and prohibit excessive emissions of pollutants. Therefore, in the float glass production line, an environmental protection system is often connected to treat the exhaust gas from the melting furnace, and the flue gas can only be discharged after treatment.

[0003] Since float glass production is a continuous and uninterrupted operation, once the environmental protection device is shut down for maintenance, it will inevitably cause direct discharge of furnace flue gas for a period of time (direct discharge of untreated flue gas), which will harm the environment.

[0004] According to many years of experience in operating environmental protection systems, environmental protection systems need to be shut down for 48 hours (2 days of shutdown) for planned maintenance after 3 to 6 months of operation, and 5 to 7 days of major maintenance after 48 months of operation, such as replacing bags, replacing catalysts, and cleaning flue dust. During the maintenance period, it is necessary to report to the local ecological environment bureau, but the exhaust gas is discharged directly without being treated by the environmental protection system, which seriously pollutes the local environment.

[0005] Therefore, in order to comply with national environmental protection requirements, in addition to connecting the environmental protection system to the float glass production line, it is necessary to connect backup environmental protection equipment for emergency replacement when the main environmental protection system is under maintenance, to ensure that the environmental protection system operates stably and meets standards in the long term, to prevent the direct discharge of furnace exhaust gas without treatment when the main environmental protection system is under maintenance, to reduce the discharge of pollutants and to improve the environment.

[0006] In a production scenario with multiple float glass production lines, replacing the environmental protection systems of multiple float glass production lines often requires designing multiple spare lines. However, if each float glass production line is equipped with a set of environmental protection spare flue gas treatment systems, multiple spare lines have a series of problems such as large floor space, high investment cost, low utilization rate of multiple sets of environmental protection spare flue gas treatment systems, high maintenance cost, and waste of resources, which greatly reduces the investment cost of enterprises. Therefore, a solution of using one spare line to replace the environmental protection systems of multiple float glass production lines has emerged.

[0007] In the flue gas treatment process, both the original environmental protection system at the outlet of the production line furnace and the backup flue gas treatment system often use SCR denitrification in the denitrification process. SCR denitrification requires the flue gas to reach a certain temperature. Therefore, in order to enable the backup flue gas treatment system to meet the temperature requirements of SCR denitrification, the backup flue gas treatment system is often in a hot state during normal operation. When the main system can be used normally and it is necessary to switch the backup flue gas treatment system back to the main system, it is also necessary to ensure that the main system is in a hot state.

[0008] In order to save resources, in the scheme of replacing the environmental protection systems of multiple float glass production lines with one standby line, the shut-down standby flue gas treatment system or main system is in a cold state and needs to be preheated. When the standby flue gas treatment system switches back to a certain group of main systems, it is necessary to draw part of the flue gas of the production line where the group of main systems is located to preheat the main system, because the main system is still in the preheating state at this time, and this part of the flue gas has not been processed by the treatment system. This part of the flue gas will be drawn into the standby flue gas treatment system that is still in use. The lower flue gas temperature of this part of the flue gas will cause the overall flue gas temperature entering the standby flue gas treatment system to decrease. At this time, if the waste heat is recovered by the waste heat boiler (in order to recycle resources, save energy and reduce emissions, the flue gas at the outlet of the production line melting furnace is often recovered in the production process, and at the same time, it is also to avoid the temperature being too high to reduce the activity of the SCR denitration catalyst), the flue gas temperature of the SCR denitration system will be too low and the reaction will be insufficient. The flue gas that has not been fully denitrated will be discharged into the atmosphere, causing environmental pollution. Utility Model Content

[0009] The technical problem to be solved by the utility model is to provide an emergency device for treating float glass smoke, which can prevent the smoke temperature of the SCR denitrification system in the standby smoke treatment system from being too low and affecting the smoke treatment effect during the process of switching the standby smoke treatment system to the main system.

[0010] In order to solve the above technical problems, the utility model provides an emergency device for float glass fume treatment, including a standby fume treatment system, which can be used to replace a main system with multiple production lines, each production line shares a connecting flue connected to the standby fume treatment system, and the standby fume treatment system is divided into a waste heat recovery section and a fume treatment section; the standby fume treatment system includes a main flue and a bypass flue, the main flue is connected to the waste heat recovery section by the connecting flue so that the flue gas first undergoes waste heat recovery and then enters the SCR denitrification system of the fume treatment section; the bypass flue is directly connected to the fume treatment section by the connecting flue so that the flue gas first enters the SCR denitrification system and then undergoes waste heat recovery; the standby fume treatment system can switch between the main flue line and the bypass flue line.

[0011] In some embodiments, the waste heat recovery section includes a waste heat boiler high temperature section and a waste heat boiler low temperature section, and an isolating switch is provided between the waste heat boiler high temperature section and the waste heat boiler low temperature section.

[0012] In some embodiments, the main flue is connected to the outlet of the communication flue and the inlet of the high temperature section of the waste heat boiler, and a first switch device with adjustable opening is provided in the main flue.

[0013] In some embodiments, the high temperature section of the waste heat boiler is connected to the flue gas treatment section via a first flue, and a second switch device with adjustable opening is provided in the first flue.

[0014] In some of the embodiments, the SCR denitration system is connected to the low-temperature section of the waste heat boiler via a second flue, and a third switch device with an adjustable opening is provided in the second flue.

[0015] In some of the embodiments, the bypass flue connects the connecting flue outlet with the flue gas treatment section, and a fourth switch device with an adjustable opening is provided in the bypass flue.

[0016] In some of the embodiments, the SCR denitration system is connected to the high temperature section of the waste heat boiler through a third flue, and a fifth switch device with an adjustable opening is provided in the third flue.

[0017] In some of the embodiments, the inlet of the SCR denitration system is connected to a dust removal system.

[0018] In some of the embodiments, the dust removal system adopts a ceramic dust removal system, and the ceramic dust removal system is provided with a multi-chamber structure, and each chamber is independent of each other.

[0019] In some embodiments, the dust removal system further includes a conditioning system, and the conditioning system outlet is connected to the ceramic dust removal system inlet for conditioning the flue gas so that the flue gas meets the needs of the ceramic dust removal system.

[0020] Compared with the prior art, the utility model has the beneficial effect of arranging a main flue and a bypass flue in the standby flue gas treatment system, wherein the standby flue gas treatment system can switch between the main flue line and the bypass flue line, and the bypass flue is directly connected to the flue gas treatment section for SCR denitrification and then waste heat recovery, thereby avoiding the flue gas temperature of the SCR denitrification system in the standby flue gas treatment system being too low and affecting the flue gas treatment effect during the process of switching the standby flue gas treatment system to the main system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The process flow chart for the standby flue gas treatment system;

[0022] Figure 2 This is a schematic diagram of the bypass flue and gate process flow of the standby flue gas treatment system. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model; it is obvious that the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments of the utility model without making creative work are within the scope of protection of the utility model.

[0024] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0025] In the description of the present utility model, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installed", "provided with", "installed / connected", "connected", etc. should be understood in a broad sense. For example, "connection" can be a wall-mounted connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be a direct connection or an indirect connection through an intermediate medium. It can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to specific circumstances.

[0026] like Figure 1 As shown, in order to be able to preheat the cold main system and the standby flue gas treatment system to a hot state during the switching process between the main system and the standby flue gas treatment system, a first heating return flue is set between the main system and the standby flue gas treatment system, and a second heating return flue is set between the standby flue gas treatment system and the main system. When the main system is switched to the standby flue gas treatment system, part of the flue gas in the production line is drawn into the standby flue gas treatment system through the connecting flue to preheat the standby flue gas treatment system, and then the part of the flue gas is returned to another main system through the second heating return flue for flue gas treatment until the smoke temperature of the standby flue gas treatment system meets the temperature requirement of SCR denitrification, and then the standby flue gas treatment system is started.

[0027] When the main system is overhauled and can be activated again, the standby flue gas treatment system needs to be switched back to the main system, and the main system needs to be preheated at this time. Part of the flue gas from the production line is drawn into the main system to preheat the main system. Since the main system has not been activated at this time, this part of the drawn flue gas needs to be treated before it can be discharged into the atmosphere. Therefore, this part of the flue gas will pass through the first heating reflux flue into the connecting flue and then enter the standby flue gas treatment system for treatment. At this time, the smoke temperature of this part of the flue gas entering the standby flue gas treatment system is lower than that when the main system is not preheated. Entering the standby flue gas treatment system will cause the smoke temperature of the standby flue gas treatment system to decrease. If this part of the flue gas is first recovered for waste heat and then enters the SCR denitrification system according to the normal path, it may not meet the SCR denitrification requirements.

[0028] Reference Figure 1-Figure 2 In order to solve the above technical problems, this embodiment provides an emergency device for float glass fume treatment, wherein the standby fume treatment system can be used to replace a main system having multiple production lines, and each production line shares a communication flue connected to the standby fume treatment system;

[0029] The standby flue gas treatment system is divided into a waste heat recovery section and a flue gas treatment section. The waste heat recovery section includes a gate plate ⑥ set between the high-temperature section of the waste heat boiler and the low-temperature section of the waste heat boiler as an isolating switch. The flue gas treatment section includes a dust removal system, an SCR denitrification system, and a desulfurization system.

[0030] like Figure 2 As shown, the backup flue gas treatment system includes a main flue and a bypass flue.

[0031] Specifically, the main flue connects the outlet of the connecting flue and the inlet of the high-temperature section of the waste heat boiler, and a gate plate ① with an adjustable opening is provided in the main flue as a first switch device; the high-temperature section of the waste heat boiler is connected to the dust removal system through the first flue, and a gate plate ② with an adjustable opening is provided in the first flue as a second switch device; the SCR denitrification system is connected to the low-temperature section of the waste heat boiler through the second flue, and a gate plate ③ with an adjustable opening is provided in the second flue as a third switch device.

[0032] The bypass flue connects the connecting flue outlet with the flue gas treatment section, and a gate plate ④ with an adjustable opening is provided in the bypass flue as a fourth switch device; the SCR denitrification system is connected with the high temperature section of the waste heat boiler through the third flue, and a gate plate ⑤ with an adjustable opening is provided in the third flue as a fifth switch device.

[0033] When the standby flue gas treatment system is operating normally, open the gates ①②③, close the gates ④⑤⑥ so that the standby flue gas treatment system forms a main flue line. In the main flue line, the flue gas enters the high-temperature section of the waste heat boiler from the connecting flue through the main flue for waste heat recovery, then enters the dust removal system through the first flue for dust removal, and then enters the SCR denitrification system for denitrification; after being treated by the SCR denitrification system, the flue gas enters the low-temperature section of the waste heat boiler through the second flue for waste heat recovery again, and then goes for desulfurization. Since the standby flue gas treatment system is operating normally, the smoke temperature of the standby flue gas treatment system can meet the temperature requirements of SCR denitrification. Therefore, in the main flue line, the flue gas first undergoes waste heat recovery and then enters the SCR denitrification system, which will not result in poor flue gas treatment effect.

[0034] When the standby is switched to the main system, as mentioned above, the smoke temperature of the standby flue gas treatment system will decrease. At this time, it is necessary to bypass the high-temperature section of the waste heat boiler and perform SCR denitrification treatment first. Open gates ④⑤⑥ and close gates ①②③ to form a bypass flue line for the standby flue gas treatment system. In the bypass flue line, the flue gas enters the dust removal system directly from the connecting flue through the bypass flue and first undergoes SCR denitrification treatment. Then, it enters the high-temperature section of the waste heat boiler from the SCR denitrification system, and then enters the low-temperature section of the waste heat boiler for secondary waste heat recovery before desulfurization. At this time, the flue gas is first subjected to SCR denitrification treatment, and then waste heat recovery can avoid the flue gas temperature of the SCR denitrification system being too low, so that the flue gas can be fully treated and will not lead to poor flue gas treatment effect.

[0035] In order to effectively reduce the impact of dust particles in the flue gas on the SCR denitrification operation and improve the denitrification efficiency and operation stability, a ceramic dust removal system is designed. Specifically, a ceramic tube dust collector is used for high-temperature dust removal. After dust removal, the particle concentration in the flue gas is less than 10mg / Nm 3 The entire dust removal system uses Q345B steel plate with a thickness of 6mm, and the insulation uses 3 layers of aluminum silicate + 1 layer of hydrophobic rock wool, and the external application of color steel tiles is 0.6mm thick.

[0036] Due to the large difference in flue gas flow rates of different production lines, the filtration speed in the ceramic tube will be very different. The filtration speed within a reasonable range is an important design requirement for dust removal effect and safe operation of the dust removal system. To solve this problem, the ceramic dust removal design adopts a multi-chamber structure, and each chamber is independent of each other: each chamber is designed with independent inlet and outlet gate valves, independent ceramic tube backflush system, independent differential pressure transmitter, thermocouple, ash hopper under the ash gate valve, maintenance manhole door, and each chamber is individually insulated. Through the switch control of the independent inlet and outlet gate valves of each chamber, the cross-sectional area of ​​the flue gas flow path and the amount of flue gas flowing through each chamber are controlled to solve the problem of filtration speed differences caused by the large differences in flue gas flow rates of different production lines.

[0037] In order to make the flue gas properties more suitable for the downstream high-temperature ceramic tube dust removal needs and achieve the effect of pre-desulfurization, in this embodiment, the dust removal system also includes a tempering system, and the tempering system outlet is connected to the ceramic dust removal system inlet for tempering the flue gas so that the flue gas adapts to the needs of the ceramic dust removal system.

[0038] In order to meet the conditioning needs of different flue gas flow rates and different flue gas properties in different production lines, the conditioning system is designed as follows:

[0039] ① Design the fluidized bed desulfurization tower as a high-temperature conditioning tower, and configure a Venturi acceleration section in the tower to solve the problem of ash falling of the conditioning agent. The maximum flue gas flow rate of the conditioning reaction section is designed to be less than 7m / s. The tower body is made of Q345B with a thickness of 8mm. The tower body is insulated with 3 layers of aluminum silicate wool + 1 layer of rock wool, and a 0.6mm color steel plate is applied externally. An online ash removal system is configured at the bottom of the tower. The flue gas flow rates of different production lines are different. The lower the flue gas flow rate, the lower the flue gas flow rate in the tower, and the lower the demand for the conditioning agent flow rate. Through the precise control of the conditioning agent flow rate, the low flue gas flow rate is matched with the low conditioning agent flow rate, which solves the problem of difficult control of the fluidized bed layer of different line flue gas flows in the same conditioning tower.

[0040] ② Design a variable frequency star feeder and use frequency adjustment to control the flow of the conditioning agent to meet the different requirements of different production lines for different flue gas flows and different flue gas properties for different conditioning dosages. After the conditioning agent is unloaded from the feeder, it flows into the conditioning tower through the air chute, which is suitable for various flow rates.

[0041] ③ A lime silo for conditioning agent storage is designed, equipped with a conditioning agent fluidization system, a lime silo vacuum release valve, a material level meter and a bag dust removal system. The silo body is made of Q235 with a thickness of 6mm. The effective volume of the silo body is designed to be 60 cubic meters, which can meet the conditioning agent dosage requirements of the maximum flue gas flow line. The silo body is insulated with 1 layer of aluminum silicate + 1 layer of hydrophobic rock wool, with staggered overlaps, and the thickness of the external colored steel tile is 0.6mm. Rain protection measures are taken on the silo roof.

[0042] The above is only a preferred specific implementation method of the utility model, but the design concept of the utility model is not limited to this. Any technician familiar with the technical field who uses this concept to make non-substantial changes to the utility model within the technical scope disclosed by the utility model shall be deemed to infringe the protection scope of the utility model.

Claims

1. An emergency device for treating float glass smoke, characterized in that: It includes a backup flue gas treatment system, which can be used to replace a main system with multiple production lines. Each production line shares a connecting flue connected to the backup flue gas treatment system, and the backup flue gas treatment system is divided into a waste heat recovery section and a flue gas treatment section; the backup flue gas treatment system includes a main flue and a bypass flue, the main flue is connected to the waste heat recovery section by the connecting flue, so that the flue gas first undergoes waste heat recovery and then enters the SCR denitrification system of the flue gas treatment section to form a main flue line; the bypass flue is directly connected to the flue gas treatment section by the connecting flue, so that the flue gas first enters the SCR denitrification system and then undergoes waste heat recovery to form a bypass flue line; the backup flue gas treatment system can switch between the main flue line and the bypass flue line.

2. The emergency device for treating float glass fume according to claim 1, characterized in that: The waste heat recovery section includes a waste heat boiler high temperature section and a waste heat boiler low temperature section, and an isolating switch is arranged between the waste heat boiler high temperature section and the waste heat boiler low temperature section.

3. The emergency device for treating float glass fume according to claim 2, characterized in that: The main flue is connected with the outlet of the communication flue and the inlet of the high temperature section of the waste heat boiler, and a first switch device with adjustable opening is provided in the main flue.

4. The emergency device for treating float glass fume according to claim 3, characterized in that: The high temperature section of the waste heat boiler is connected to the flue gas treatment section through a first flue, and a second switch device with adjustable opening is provided in the first flue.

5. The emergency device for treating float glass fume according to claim 4, characterized in that: The SCR denitration system is connected to the low-temperature section of the waste heat boiler via a second flue, and a third switch device with an adjustable opening is provided in the second flue.

6. The emergency device for treating float glass fume according to claim 2, characterized in that: The bypass flue is connected to the communication flue outlet and the flue gas treatment section, and a fourth switch device with an adjustable opening is provided in the bypass flue.

7. The emergency device for treating float glass fume according to claim 6, characterized in that: The SCR denitration system is connected to the high temperature section of the waste heat boiler through a third flue, and a fifth switch device with an adjustable opening is provided in the third flue.

8. The emergency device for treating float glass fume according to claim 1, characterized in that: The inlet of the SCR denitration system is connected to the dust removal system.

9. The emergency device for treating float glass smoke according to claim 8, characterized in that: The dust removal system adopts a ceramic dust removal system, and the ceramic dust removal system is provided with a multi-chamber structure, and each chamber is independent of each other.

10. The emergency device for treating float glass smoke according to claim 9, characterized in that: The dust removal system also includes a conditioning system, and the conditioning system outlet is connected to the ceramic dust removal system inlet for conditioning the flue gas so that the flue gas meets the needs of the ceramic dust removal system.

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