Coated glass waste gas treatment method and treatment system

Abstract

The invention discloses a coated glass waste gas treatment method and a coated glass waste gas treatment system, and relates to the technical field of glass production waste gas treatment. According to the coated glass waste gas treatment method, a coated glass waste gas treatment system is adopted for operation, and the coated glass waste gas treatment system comprises an incinerator, a condenser, a dust remover and a chimney which are connected in sequence; and the incinerator is connected with the coated glass waste gas input pipeline through a conveying pipeline. According to the invention, by reasonably designing each device and parameters thereof in the waste gas treatment system, the technical problem that silane and intermediate products in the waste gas generated in the on-line solar control coating production system are flammable and explosive is solved at a lower cost, and the concentration of each component in the treated waste gas at a discharge port is far lower than the national standard; in addition, according to the coated glass waste gas treatment method, the secondary pollution problem of waste gas treatment is avoided through internal circulation.

Description

Technical Field

[0001] The present invention relates to the technical field of waste gas treatment in glass production, and in particular to a method and system for treating waste gas from coated glass. Background Art

[0002] Online solar control coated glass is a kind of coated glass that is selective for the wavelength range of sunlight. It can reflect some wavelengths of sunlight to achieve the effect of shading, thereby achieving energy saving. With the improvement of building energy-saving standards, the market for this type of glass is becoming wider and wider. Online solar control coated glass is usually prepared by APCVD method. The waste gas generated includes nitrogen, polysilicon dust produced by thermal decomposition of silane, and silicon dioxide generated by the reaction of exhaust gas and air, as well as a small amount of ethylene, carbon dioxide and hydrogen. With stricter environmental protection requirements, especially the promulgation of GB26453-2022 "Flat Glass Industry Air Pollutant Emission Standard", the dust emission standard has been reduced from 50mg / m3 to 30mg / m3. The waste gas emission control of online solar control coated glass is imperative.

[0003] The existing waste gas treatment system specially used for online sunlight control coated glass is still in the initial development stage in the field of coated glass, and there are the following difficulties in treating its waste gas: First, most companies use a comprehensive waste gas treatment system, that is, a waste gas treatment system that can treat all waste gases from CVD coating. The configuration cost of this system is too high; second, the safety issue. Silane, ethylene and hydrogen in the waste gas are prone to explosion after being deposited to a certain extent in the pipeline, affecting production safety and equipment safety. This is also one of the difficulties in treating waste gas from online sunlight control coated glass; third, silane in the waste gas is an oily substance with a high viscosity. If dehydrogenation is not sufficient, it will stick to the dust collector and adsorb dust, thereby blocking the pores of the dust collector and affecting the dust removal efficiency.

[0004] Therefore, in response to the above-mentioned problems and difficulties in waste gas treatment in the field of online solar control coated glass, it is necessary to develop a waste gas treatment method and treatment system that can match the operation of the online solar control coated glass production system to meet the requirements of high treatment efficiency, low cost, low dust emissions and minimizing explosion safety hazards. Summary of the invention

[0005] The main purpose of this invention is to develop a waste gas treatment method and treatment system specifically for the field of online solar control coated glass, which can not only match the online solar control coated glass production system, improve production efficiency and exhaust gas treatment efficiency, but also avoid the explosion limit of explosive gases in the waste gas. The waste gas discharged after treatment is far lower than the current national standard GB26453-2022 "Glass Industry Air Pollutant Emission Standards" requirements, thereby meeting the design concept of safety, pollution-free, high efficiency and low cost.

[0006] To achieve the above object, the present invention proposes a method for treating waste gas from coated glass, which is operated by a waste gas treatment system for coated glass. The waste gas treatment system for coated glass comprises an incinerator, a condenser, a dust collector and a chimney which are sequentially connected through a conveying pipeline; the incinerator is connected to a waste gas input pipeline for coated glass through a conveying pipeline; the waste gas treatment method for coated glass comprises the following steps:

[0007] S1. The exhaust gas enters the delivery pipeline through the coated glass exhaust gas input pipeline, and the air supply valve on the air supply pipeline is opened at the same time, and the air enters the delivery pipeline through the air supply pipeline and mixes with the exhaust gas to form mixed exhaust gas;

[0008] S2, the mixed waste gas enters the incinerator for incineration treatment, and the flow rate of the mixed waste gas entering the incinerator and the incineration temperature in the incinerator are controlled;

[0009] S3, the mixed exhaust gas after incineration is cooled by the condenser and dedusted by the dust collector, and then discharged from the chimney under the action of the fan;

[0010] In the step S1, the flow rate of the waste gas in the coated glass waste gas input pipeline is 430m3 / h to 580m3 / h, and the flow rate of the air in the air supply pipeline is 110m3 / h to 190m3 / h;

[0011] In the step S2, the incineration temperature in the incinerator is controlled to be above 1000°C.

[0012] In one embodiment, in step S1, the waste gas includes ethylene, nitrogen, hydrogen, silicon powder, silane, and silane thermal decomposition intermediates;

[0013] Wherein, the silane includes SiH4, Si2H6, SiH8 and Si4H 10 One or more of .

[0014] In one embodiment, in the step S1, the volume fraction of the concentration of silane and silane thermal decomposition intermediates in the mixed exhaust gas is not greater than 0.79%, and the volume fraction of the concentration of ethylene in the mixed exhaust gas is not greater than 0.4%.

[0015] In one embodiment, in step S2, the mixed exhaust gas flow rate in the incinerator is controlled at 650m3 / h to 820m3 / h.

[0016] In one embodiment, in step S3, after the mixed exhaust gas that has been incinerated is cooled by a condenser, the temperature of the mixed exhaust gas is controlled below 200°C.

[0017] The present invention also proposes a coated glass waste gas treatment system, which applies the above-mentioned coated glass waste gas treatment method;

[0018] The coated glass waste gas treatment system comprises an incinerator, a condenser, a dust collector and a chimney which are sequentially connected through a conveying pipeline. The incinerator is connected to a coated glass waste gas input pipeline through the conveying pipeline.

[0019] In one embodiment, the coated glass waste gas input pipeline is connected to the online sunlight control coating production system to receive the waste gas generated by the CVD reactor in the online sunlight control coating production system.

[0020] In one embodiment, an air supply pipeline is further provided on the delivery pipeline between the incinerator and the coated glass waste gas input pipeline, for introducing air into the coated glass waste gas treatment system.

[0021] In one embodiment, an air supply valve is provided on the air supply pipeline to adjust the amount of air entering to ensure that the exhaust gas concentration in the coated glass exhaust gas treatment system is below the explosion concentration and to ensure that the exhaust gas is effectively burned in the incinerator.

[0022] In one embodiment, a fan is further provided on the conveying pipeline between the dust collector and the chimney. The fan is a variable frequency fan for providing negative pressure for the system and ensuring the pressure difference between the system and the outside by adjusting the fan frequency.

[0023] The technical solution of the present invention designs a method and system for treating waste gas from coated glass, and adopts a combustion treatment process to treat the waste gas generated in the production process of online sunlight-controlled coated glass. By reasonably designing the various components in the waste gas treatment device and their related parameters, the technical problem of flammable and explosive silane and intermediate products in the waste gas is solved at a relatively low cost. The concentrations of each component in the waste gas at the discharge port after treatment are far lower than the requirements of the current national standard GB26453-2022 "Glass Industry Air Pollutant Emission Standards". In addition, the above-mentioned method for treating waste gas from coated glass avoids the secondary pollution problem of waste gas treatment through internal circulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0025] Figure 1 A flowchart of a waste gas treatment system for coated glass according to an embodiment of the present invention;

[0026] Figure 2 The XRD detection diagram of dust in the untreated and treated exhaust gases in Example 1 of the present invention;

[0027] Figure 3 This is a Fourier infrared detection image of dust in the untreated and treated exhaust gases in Example 1 of the present invention.

[0028] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0031] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0032] The technical problem to be solved by the present application is: At present, there are the following difficulties in treating the waste gas generated in the production process of online solar control coated glass: The first point is that the waste gas treatment system specially used for online solar control coated glass is still in the initial development stage in this field. Most companies use a comprehensive waste gas treatment system, that is, a waste gas treatment system that can treat all waste gases from CVD coating, but the types of waste gas generated in the production process of online solar control coated glass are relatively small, and the cost of configuring this system is too high; the second point is the safety issue. After the silane, ethylene and hydrogen in the waste gas are deposited to a certain extent in the pipeline, they are prone to explosion, affecting production safety and equipment safety; the third point is that the silane in the waste gas is an oily substance with a high viscosity. If the dehydrogenation is not sufficient, it will stick to the dust collector and adsorb dust, thereby blocking the pores of the dust collector, thereby affecting the dust removal efficiency.

[0033] In order to solve the above technical problems, a waste gas treatment system and method are designed to match the operation of the online sunlight-controlled coated glass production system, while meeting the requirements of high treatment efficiency, low cost, low dust emission and minimizing explosion safety hazards. The present invention proposes a coated glass waste gas treatment method and treatment system.

[0034] The present invention proposes a method for treating waste gas from coated glass, wherein the waste gas is treated by a waste gas treatment system for coated glass, wherein the waste gas treatment system for coated glass comprises an incinerator, a condenser, a dust collector and a chimney which are sequentially connected through a conveying pipeline; the incinerator is connected to a waste gas input pipeline for coated glass through a conveying pipeline. Specifically, the following steps are included:

[0035] S1, the exhaust gas enters the delivery pipeline through the coated glass exhaust gas input pipeline, and at the same time, the air enters the delivery pipeline through the air supply pipeline and mixes with the exhaust gas to form a mixed exhaust gas;

[0036] S2, the mixed waste gas enters the incinerator for incineration treatment, and the flow rate of the mixed waste gas entering the incinerator and the incineration temperature in the incinerator are controlled;

[0037] S3, the mixed exhaust gas after incineration is cooled by the condenser and dedusted by the dust collector, and then discharged from the chimney under the action of the fan;

[0038] In step S1, the flow rate of the waste gas in the coated glass waste gas input pipeline is 430m 3 / h~580m 3 / h, the air flow rate in the air supply pipeline is 110m 3 / h~190m 3 / h;

[0039] In the step S2, the incineration temperature in the incinerator is controlled to be above 1000°C.

[0040] It should be noted that in step S1, the waste gas in the waste gas input pipeline of the coated glass is a flammable and explosive gas, mainly containing silane, ethylene, and the intermediate products of silane thermal decomposition reaction [SiH2] and [SiH2] X etc., wherein silane and the intermediate products of silane thermal decomposition reaction [SiH2] and [SiH2] X The volume concentration of silane has exceeded 1.1%, while the lower explosion limit of silane in the air is 0.8%. Therefore, the exhaust gas in the exhaust gas input pipeline of the coated glass may explode when it encounters an ignition source. Therefore, the pipeline from the sunlight control coated glass production system to the exhaust gas input pipeline and the air supply pipeline of the coated glass needs to be strictly explosion-proof, and parameters such as pipeline pressure need to be mastered in a timely manner. It should also be noted that the internal pressure of the pipeline of the coated glass exhaust gas treatment system needs to be controlled by a fan. On the one hand, after the air supply valve is opened, the air can quickly enter the pipeline to dilute the exhaust gas due to the pressure difference. On the other hand, it can prevent the exhaust gas in the pipeline from leaking out to avoid secondary pollution.

[0041] It should also be noted that in step S1, the flow rate of the waste gas in the waste gas input pipeline of the coated glass is 430m3 / h~580m3 / h, and the flow rate of the air in the air supply pipeline is 110m3 / h~190m3 / h. It should be noted that in order to prevent explosion, air needs to be introduced into the pipeline to dilute the waste gas before entering the incinerator; wherein, the flow rate of waste gas extracted from the waste gas treatment system mainly depends on the amount of waste gas generated during the production process, and the flow rate of supplementary air depends on the combustion efficiency in the incinerator and the concentration of flammable substances in the waste gas in the pipeline is reduced to a safe concentration. It should also be noted that the exhaust gas treatment system has little effect on the waste gas flow rate and air flow rate in the present invention by exhaust gas extraction on both sides and unilateral exhaust gas extraction, and the corresponding flow data can be used. Optionally, when the exhaust gas treatment system extracts exhaust gas, the exhaust gas flow rate can be any one of 430m3 / h, 450m3 / h, 480m3 / h, 490m3 / h, 510m3 / h, 530m3 / h, 540m3 / h, 560m3 / h, 580m3 / h, and any value in the above range is acceptable. Optionally, the flow rate of air in the air supply pipeline can be any one of 110m3 / h, 130m3 / h, 140m3 / h, 160m3 / h, 180m3 / h, 190m3 / h, and any value in the above range is acceptable.

[0042] It should also be noted that in step S2, the incineration temperature in the incinerator is controlled to be above 1000°C. It should be noted that, from the perspective of thermodynamics, silane and the intermediate products [SiH2] and [SiH2] XAmorphous silicon begins to crystallize at 680°C to decompose silicon and hydrogen, and continues to crystallize until all the hydrogen in the amorphous composition is released. In order to completely dehydrogenate the silane intermediate product in the short time that the exhaust gas passes through the incinerator, and the combustible gas is completely burned, the incineration temperature in the incinerator needs to be controlled above 1000°C. Optionally, from the perspective of energy efficiency, the incineration temperature of the incinerator is controlled at 1000-1200°C. Optionally, the incineration temperature of the incinerator can be any one of 1000°C, 1050°C, 1080°C, 1100°C, 1150°C, and 1200°C, and any value within the above range is acceptable.

[0043] In one embodiment, in step S1, the waste gas includes ethylene, nitrogen, hydrogen, silicon powder, silane and silane thermal decomposition intermediates; wherein the silane includes SiH4, Si2H6, SiH8 and Si4H 10 One or more of. It should be noted that the waste gas treatment system and method of the present invention are designed for an online sunlight control coated glass production system, and the chemical reaction involved is mainly the process of silane being decomposed into intermediate products in a CVD reactor and the intermediate products reacting on a glass substrate to form an amorphous silicon film. Therefore, the types of components to be treated in the waste gas are limited to silane, ethylene, hydrogen, silicon powder and silicon dioxide, silane intermediate products [SiH2] and [SiH2] X Of course, if other reaction raw materials are added to the above reaction, the present invention also extends to the treatment of other components in the exhaust gas under the premise of effective treatment. It should also be noted that SiH4, Si2H6, SiH8 and Si4H 10 It is a silane commonly used in vapor deposition reactions. The types of silanes that can be treated by the waste gas treatment system of the present invention are not limited to the silanes listed above. Any silane that can be used to prepare online solar control coated glass can be treated using the waste gas treatment method and treatment system of the present invention.

[0044] In one embodiment, in step S1, the volume fraction of the concentration of silane and the silane thermal decomposition intermediate product in the mixed exhaust gas is not greater than 0.79%, and the volume fraction of the ethylene concentration in the mixed exhaust gas is not greater than 0.4%. It should be noted that the silane intermediate product [SiH2] and [SiH2] X It is a flammable and explosive substance with an explosion limit (volume concentration) of 0.8-98%, an explosion limit (volume concentration) of ethylene of 2.7-36%, and an explosion limit of hydrogen of 4.0-75.6%. It should also be noted that the flow rate of the waste gas extracted from the waste gas input pipeline of the coated glass in the waste gas treatment system of the present invention is 430m3 / h~580m3 / h, wherein the silane and its intermediate products [SiH2] and [SiH2] in the waste gas are XThe volume concentration range of is about 1.11-1.47%, and the volume concentration range of ethylene is 0.207-0.27%. Within this range, it is very easy to explode when it comes into contact with an ignition source. Therefore, while controlling the concentrations of the two gases at the lower explosion limit, it is also necessary to prevent the interaction between the two flammable gases from increasing the concentration of the flammable gases in disguise and causing an explosion. Therefore, the concentrations of the two gases need to be controlled at a lower level.

[0045] In one embodiment, in step S2, the mixed exhaust gas flow rate in the incinerator is controlled at 650m3 / h to 820m3 / h. It should be noted that if the mixed exhaust gas flow rate in the combustion furnace is too low, it will lead to incomplete combustion of the fuel, which will produce secondary pollution on the one hand, and will also cause carbon deposition on the other hand, affecting equipment operation and production safety. Optionally, the mixed exhaust gas flow rate of the incinerator can be any one of 650m3 / h, 690m3 / h, 760m3 / h, 790m3 / h, 800m3 / h, and 820m3 / h, and any value within the above range is acceptable.

[0046] In one embodiment, in step S3, after the mixed exhaust gas that has been incinerated is cooled by the condenser, the temperature of the mixed exhaust gas is controlled below 200°C. It should be noted that the main purpose of using a condensing fan to cool the mixed gas is to prevent the mixed exhaust gas from being too hot and damaging subsequent equipment such as the dust collector and the fan. It should also be noted that according to the flow rate of the mixed gas in the incinerator, the condenser can effectively control the temperature of the mixed exhaust gas below 200°C. Therefore, the present invention does not emphasize the flow rate of the mixed exhaust gas in the condenser. The flow rate of the mixed gas in the incinerator can be used, and the present invention does not make a separate restriction. It should also be noted that the upper limit of the temperature of the mixed exhaust gas at the outlet of the condenser needs to be limited. Optionally, the temperature of the mixed exhaust gas at the outlet of the condenser is 140-200°C. The purpose here is to prevent the mixed exhaust gas from entering the dust collector from being too cold. The water molecules therein are liquefied into water on the dust collector, and after mixing with the dust, the dust collector is blocked, affecting the dust removal efficiency. Optionally, the temperature of the mixed exhaust gas at the condenser outlet may be any one of 140° C., 150° C., 160° C., 180° C., and 200° C., and any value within the above range may be sufficient.

[0047] The present invention also proposes a coated glass waste gas treatment system, which applies the above-mentioned coated glass waste gas treatment method; the coated glass waste gas treatment system includes an incinerator, a condenser, a dust collector and a chimney connected in sequence through a conveying pipeline; the incinerator is connected to the coated glass waste gas input pipeline through a conveying pipeline. It should be noted that the core step in the production process of online sunlight-controlled coated glass is that the reaction raw materials enter the CVD reactor and undergo thermal decomposition to react on the glass substrate to generate an amorphous silicon film; specifically, the reaction raw materials include a certain proportion of silane, ethylene and nitrogen. During the production process, only 15-25% of the silane in the reaction raw materials is converted into an amorphous silicon film layer, and the rest exists in the waste gas in the form of reaction intermediates or decomposition products. According to analysis and determination, the main components of the waste gas generated in the production process of online sunlight-controlled coated glass include silane, silane intermediates [SiH2] and [SiH2] X , ethylene, hydrogen, silicon powder, silicon dioxide, etc. Among them, the silane intermediates 〔SiH2〕 and 〔SiH2〕 X It is flammable and explosive. When the concentration of silane deposited in the pipeline increases, it will react rapidly and explode when it encounters air. Secondly, the silane intermediate products [SiH2] and [SiH2] that are not fully dehydrogenated X It is an oily substance that easily sticks to the dust collector and affects the dust removal efficiency.

[0048] Optionally, a draft device is built into the coated glass waste gas input pipeline to introduce waste gas from the online sunlight-controlled coated glass production system into the coated glass waste gas treatment system via the coated glass waste gas input pipeline.

[0049] Optionally, a burner is built into the incinerator, which can completely burn the unreacted silane and intermediate products, ethylene, hydrogen, etc. in the exhaust gas in an environment with sufficient oxygen, completely decompose the combustible gas, and completely dehydrogenate the silane and intermediate products to generate silicon powder or silicon dioxide. It should be noted that the longer the reaction time of the incinerator, the more time the components in the mixed exhaust gas have to complete collision, aggregation, and growth, which is conducive to the growth of powdered particles of the amorphous silicon product and the subsequent dust removal steps.

[0050] Optionally, the dust collector is used to remove silicon powder, silicon dioxide and other dust generated after the combustion of exhaust gas; after the exhaust gas is burned at a temperature above 1000°C in the incinerator, silane and its intermediate products have been completely dehydrogenated, and the generated silicon powder or silicon dioxide has low viscosity and is not easy to stick to and clog the dust collector; optionally, based on cost considerations, the dust collector adopts a bag dust collector with a simple structure and lower cost, and the bag dust collector can withstand a high temperature of 250°C; optionally, the dust collector adopts a backflush structure to maintain continuous and stable operation of the dust collector, and the bag dust collector is provided with a compressed air pipe for backflush dust from the bags to ensure that the bags are unobstructed.

[0051] Optionally, the present invention does not limit the type of dust collector, and the dust collector can be any one of a bag dust collector, a cyclone dust collector, an electrostatic dust collector, a water film dust collector, a wet dust collector, and a pulse jet bag dust collector, as long as it can effectively intercept dust particles in the exhaust gas.

[0052] Optionally, a condenser is provided between the incinerator and the dust collector to cool the exhaust gas after incineration to prevent the exhaust gas from being too hot and damaging the dust collector; the condenser can be a water cooling device or an air cooling device. Optionally, the condenser is a condensing fan; Optionally, the condensing fan is cooled by circulating water; the circulating water adjusts the water temperature through the combined action of the temperature sensor, the flow rate of the condensing water and the frequency of the condensing fan, and finally controls the exhaust gas temperature at the outlet of the condenser.

[0053] Optionally, the present invention does not limit the type of condenser. The condenser can be any one of a water-cooled condenser, an air-cooled condenser, an evaporative condenser and a spray condenser; it can also be any one of a plate condenser, a spiral plate condenser, a tubular condenser and a stratified condenser, as long as it can achieve effective cooling of the exhaust gas.

[0054] Optionally, a washing tower may be provided between the dust collector and the chimney, wherein a spray device is provided in the washing tower for secondary dust removal of the waste gas treated by the dust collector and then discharged through the chimney. Optionally, an induced draft fan may be provided at the air outlet of the washing tower.

[0055] In one embodiment, the coated glass waste gas input pipeline is connected to the online sunlight control coating production system to receive the waste gas generated by the CVD reactor in the online sunlight control coating production system.

[0056] In one embodiment, an air supply pipeline is further provided on the delivery pipeline between the incinerator and the coated glass waste gas input pipeline, for introducing air into the coated glass waste gas treatment system. It should be noted that one end of the air supply pipeline is connected to the air, and the other end is connected to the coated glass waste gas input pipeline. The air is mixed with the waste gas through the air supply pipeline to dilute the waste gas, thereby reducing the concentration of explosive substances to below the explosion limit.

[0057] In a specific embodiment, an air supply valve is provided on the air supply pipeline to adjust the amount of air entering to ensure that the exhaust gas concentration in the coated glass exhaust gas treatment system is below the explosion concentration and to ensure that the exhaust gas is effectively burned in the incinerator. It should be noted that the air supply valve is used to control the flow rate of air. If the air flow rate is too high, the proportion of exhaust gas in the mixed exhaust gas is too low, which may easily lead to too low exhaust gas treatment efficiency to meet production needs; if the air flow rate is too low, the explosive components in the exhaust gas cannot be effectively diluted, which poses certain safety hazards.

[0058] In one embodiment, a fan is further provided on the conveying pipeline between the dust collector and the chimney. The fan is a variable frequency fan for providing negative pressure for the system. The pressure difference between the system and the outside is ensured by adjusting the fan frequency.

[0059] The present invention is further described below by means of specific embodiments:

[0060] Example 1

[0061] In Example 1, the relevant parameters in the online sunlight control coated glass production equipment are as follows:

[0062] The float glass production line has a pulling capacity of 595t / d in the tin bath forming area, a glass pulling speed of 463m / h, and an average glass thickness of 6mm. The length of the CVD coating reactor is 3900mm, and the height of the reactor from the glass plate is 3mm. The reaction gases include: silane (SiH4) and nitrogen mixed gas (volume ratio of 1:4), ethylene and nitrogen, of which the mixed gas flow rate is 55slpm, the ethylene flow rate is 10slpm, and the nitrogen flow rate is 65slpm.

[0063] In Example 1, the flowchart of the coated glass waste gas treatment system is specifically referred to Figure 1 , the relevant parameters of each device are as follows:

[0064] Exhaust gas flow rate in the coated glass exhaust gas input pipeline is 540m 3 / h, the air flow rate controlled by the air supply valve is 160m3 / h, the volume concentration of silane and its intermediates in the mixed exhaust gas entering the incinerator is 0.70%, and the concentration of ethylene is 0.34%. The concentrations of silane and its intermediates and ethylene are all at the lower limit of the explosion range. The mixed exhaust gas flow rate in the incinerator is 700m3 / h, the incineration temperature of the incinerator is 1100℃, and the mixed exhaust gas temperature at the condenser outlet is 184℃.

[0065] Performance testing:

[0066] 1. With reference to the standard GB 26453-2022 "Emission Standards of Air Pollutants for Flat Glass Industry", the exhaust gas at the chimney (exhaust pipe) was collected and relevant measurements were performed. The measurement results are shown in Table 1.

[0067] 2. XRD tests were performed on the dust in the waste gas that had not been treated by the coated glass waste gas treatment system and the waste gas that had been treated by the waste gas treatment system. The test results are shown in Figure 2 .

[0068] 3. Infrared detection of dust in the waste gas that has not been treated by the coated glass waste gas treatment system and the waste gas that has been treated by the waste gas treatment system is performed. The test results are shown in Figure 3 .

[0069] Table 1

[0070]

[0071] Through Figure 2 , Figure 3 By analyzing Table 1, we can get: Figure 2 In the figure, the green line is the XRD test diagram of dust in the exhaust gas that has not been treated by the exhaust gas system. The main component of the dust is amorphous silicon, which shows a wide scattering peak, and the change of the scattering peak is relatively gentle; the black line is the XRD test diagram of dust in the exhaust gas treated by the exhaust gas system. Sharp diffraction peaks can be observed, which correspond to crystalline silicon or crystalline silicon dioxide generated after high-temperature incineration treatment; by comparison, it can be found that the main component of the dust is transformed from amorphous substances to crystalline substances after the exhaust gas is treated.

[0072] Figure 3 In the infrared detection image, 800cm -1 The peak detected at 1060 cm-1 corresponds to the Si-H bond. -1 The peak detected at 2000-2500 cm-1 corresponds to the Si-O bond. -1 The detection peak at should be caused by the carrier of the powder (potassium bromide crystals), which can be ignored. The dust that has not been treated by the exhaust gas treatment system contains Si-H bonds, which are flammable and explosive dust (red line in the figure). After being treated by the exhaust gas treatment system, the Si-H in the dust basically disappears (black line in the figure), which shows that the amorphous silicon in the treated dust is basically converted into crystalline silicon or crystalline silicon dioxide.

[0073] By analyzing Table 1, the emission limits in Table 1 correspond to the requirements of the national standard GB 26453-2022 "Emission Standards for Air Pollutants in Glass Industry". The measured concentrations of particulate matter, hydrogen chloride, fluoride, tin and its compounds in the treated exhaust gas in Table 1 are significantly lower than the standard emission limits, indicating that the coated glass exhaust gas treatment system in this embodiment has a good exhaust gas treatment effect. At the same time, the flow rate measured in Table 1 in Example 1 is used as the benchmark flow rate, and the relevant data in Example 2 and Example 3 are measured based on this standard.

[0074] Example 2

[0075] In Example 2, the relevant parameters in the online sunlight control coated glass production equipment are as follows:

[0076] The float glass production line has a pulling capacity of 595t / d in the tin bath forming area, a glass pulling speed of 551m / h, and an average glass thickness of 4.5mm. The length of the CVD coating reactor is 3900mm, and the height of the reactor from the glass plate is 3mm. The reaction gases include: silane (SiH4) and nitrogen mixed gas (volume ratio of 1:4), ethylene and nitrogen, of which the mixed gas flow rate is 68slpm, the ethylene flow rate is 10slpm, and the nitrogen flow rate is 52slpm.

[0077] In Example 2, the flowchart of the coated glass waste gas treatment system is specifically referred to Figure 1 , the relevant parameters of each device are as follows:

[0078] Exhaust flow rate in the exhaust gas input pipeline of coated glass 500m 3 / h, the air supply valve controls the air flow rate to be 180m3 / h, the volume concentration of silane and its intermediates in the mixed exhaust gas entering the incinerator is 0.74%, and the concentration of ethylene is 0.33%. The concentrations of silane and its intermediates and ethylene are all at the lower limit of the explosion range. The mixed exhaust gas flow rate in the incinerator is 680m3 / h, the incineration temperature of the incinerator is 1000℃, and the mixed exhaust gas temperature at the condenser outlet is 178℃.

[0079] Performance testing:

[0080] Referring to the standard GB 26453-2022 "Emission Standards of Air Pollutants for Flat Glass Industry", the exhaust gas at the chimney (exhaust pipe) was collected and relevant measurements were performed. The measurement results are shown in Table 2.

[0081] Table 2

[0082]

[0083]

[0084] By analyzing Table 2, it can be obtained that the actual measured concentration of the treated exhaust gas is significantly lower than the standard emission limit, which shows that the coated glass exhaust gas treatment system in this embodiment has a good exhaust gas treatment effect.

[0085] Example 3

[0086] In Example 3, the relevant parameters in the online sunlight control coated glass production equipment are as follows:

[0087] The float glass production line has a pulling capacity of 551t / d in the tin bath forming area, a glass pulling speed of 527m / h, and an average glass thickness of 5mm. The length of the CVD coating reactor is 3900mm, and the height of the reactor from the glass plate is 3mm. The reaction gases include: silane (SiH4) and nitrogen mixed gas (volume ratio of 1:4), ethylene and nitrogen, of which the mixed gas flow rate is 57slpm, the ethylene flow rate is 10slpm, and the nitrogen flow rate is 63slpm.

[0088] In Example 3, the flowchart of the coated glass waste gas treatment system is specifically referred to Figure 1 , the relevant parameters of each device are as follows:

[0089] Exhaust gas flow rate in the coated glass exhaust gas input pipeline is 520m 3 / h, the air flow rate controlled by the air supply valve is 170m3 / h, the volume concentration of silane and its intermediates in the mixed exhaust gas entering the incinerator is 0.74%, and the concentration of ethylene is 0.35%. The concentrations of silane and its intermediates and ethylene are all at the lower limit of the explosion range. The mixed exhaust gas flow rate in the incinerator is 690m3 / h, the incineration temperature of the incinerator is 1200℃, and the mixed exhaust gas temperature at the condenser outlet is 186℃.

[0090] Performance testing:

[0091] Referring to the standard GB 26453-2022 "Emission Standards of Air Pollutants for Flat Glass Industry", the exhaust gas at the chimney (exhaust pipe) was collected and relevant measurements were performed. The measurement results are shown in Table 3.

[0092] Table 3

[0093]

[0094] By analyzing Table 3, it can be obtained that the actual measured concentration of the treated exhaust gas is significantly lower than the standard emission limit, which shows that the coated glass exhaust gas treatment system in this embodiment has a good exhaust gas treatment effect.

[0095] In summary, the coated glass waste gas treatment system of the present invention has a good treatment effect on the waste gas generated in the production process of online sunlight-controlled coated glass, and has a good treatment effect on the basis of low cost of the treatment system equipment.

[0096] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A method for treating waste gas from coated glass, characterized in that: The coated glass waste gas treatment system is used for operation, and the coated glass waste gas treatment system includes an incinerator, a condenser, a dust collector and a chimney which are sequentially connected through a conveying pipeline; the incinerator is connected to the coated glass waste gas input pipeline through the conveying pipeline; The coated glass waste gas treatment method comprises the following steps: S1. The exhaust gas enters the delivery pipeline through the coated glass exhaust gas input pipeline, and the air supply valve on the air supply pipeline is opened at the same time, and the air enters the delivery pipeline through the air supply pipeline and mixes with the exhaust gas to form mixed exhaust gas; S2, the mixed waste gas enters the incinerator for incineration treatment, and the flow rate of the mixed waste gas entering the incinerator and the incineration temperature in the incinerator are controlled; S3, the mixed exhaust gas after incineration is cooled by the condenser and dedusted by the dust collector, and then discharged from the chimney under the action of the fan; In the step S1, the flow rate of the waste gas in the coated glass waste gas input pipeline is 430m3 / h to 580m3 / h, and the flow rate of the air in the air supply pipeline is 110m3 / h to 190m3 / h; In the step S2, the incineration temperature in the incinerator is controlled to be above 1000°C.

2. The method for treating waste gas from coated glass according to claim 1, characterized in that: In step S1, the waste gas includes ethylene, nitrogen, hydrogen, silicon powder, silane and silane thermal decomposition intermediates; Wherein, the silane includes SiH4, Si2H6, SiH8 and Si4H 10 One or more of .

3. The method for treating waste gas from coated glass according to claim 1, characterized in that: In the step S1, the volume fraction of the concentration of silane and silane thermal decomposition intermediate products in the mixed exhaust gas is not greater than 0.79%, and the volume fraction of the concentration of ethylene in the mixed exhaust gas is not greater than 0.4%.

4. The method for treating waste gas from coated glass according to claim 1, characterized in that: In the step S2, the mixed exhaust gas flow rate in the incinerator is controlled at 650m3 / h to 820m3 / h.

5. The method for treating waste gas from coated glass according to claim 1, characterized in that: In the step S3, after the mixed exhaust gas that has been incinerated is cooled by a condenser, the temperature of the mixed exhaust gas is controlled below 200°C.

6. A coated glass waste gas treatment system, characterized in that: A method for treating waste gas from coated glass according to any one of claims 1 to 5; The coated glass waste gas treatment system comprises an incinerator, a condenser, a dust collector and a chimney which are sequentially connected through a conveying pipeline. The incinerator is connected to a coated glass waste gas input pipeline through the conveying pipeline.

7. The coated glass waste gas treatment system according to claim 6, characterized in that: The coated glass waste gas input pipeline is connected to the online sunlight control coating production system and is used to receive the waste gas generated by the CVD reactor in the online sunlight control coating production system.

8. The coated glass waste gas treatment system according to claim 6, characterized in that: An air supply pipeline is also provided on the delivery pipeline between the incinerator and the coated glass waste gas input pipeline, which is used to introduce air into the coated glass waste gas treatment system.

9. The coated glass waste gas treatment system according to claim 8, characterized in that: The air supply pipeline is provided with an air supply valve for adjusting the amount of air entering to ensure that the exhaust gas concentration in the coated glass exhaust gas treatment system is below the explosion concentration and to ensure that the exhaust gas is effectively burned in the incinerator.

10. The coated glass waste gas treatment system according to claim 6, characterized in that: A fan is also provided on the conveying pipeline between the dust collector and the chimney. The fan is a variable frequency fan, which is used to provide negative pressure for the system and ensure the pressure difference between the system and the outside world by adjusting the fan frequency.

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