Novel incineration pretreatment process for high-concentration waste gas in hazardous waste industry

Abstract

The invention relates to the technical field of waste gas treatment, in particular to a novel incineration pretreatment process for high-concentration waste gas in the hazardous waste industry. The method comprises the steps that firstly, waste gas enters a liquid seal system; 2, treating the waste gas by a liquid sealing system; step 3, vacuum analysis; 4, waste gas recovery and liquid sealing agent regeneration; step 5, RTO system processing; in the novel incineration pretreatment process for the high-concentration waste gas in the hazardous waste industry, targeted treatment can be carried out through the liquid seal system according to the concentration of the waste gas, the concentration of the high-concentration waste gas is reduced, the concentration of the low-concentration waste gas is improved, the suitability of the waste gas entering an RTO system is improved, natural gas consumption of the RTO system is reduced, the energy cost is reduced, and meanwhile, the environment is protected. When a tempering accident occurs, flame returning can be effectively prevented, the safety of a front-end device area is guaranteed, secondary disasters are completely eradicated, the unique composite liquid sealing agent can dissolve complex waste gas components, good conditions are provided for follow-up treatment, and the environmental protection property of the whole treatment process is improved.

Description

Technical Field

[0001] The invention relates to the technical field of waste gas treatment, and in particular to a new process for incineration pretreatment of high-concentration waste gas in the hazardous waste industry. Background Art

[0002] In the hazardous waste industry, there have always been some problems with waste gas treatment. The waste gas emitted by the hazardous waste industry has difficulties such as large fluctuations in emission and concentration, complex composition, high viscosity and large molecular weight components, and certain corrosiveness, which makes it difficult for waste gas devices to operate stably. In recent years, safety accidents of environmental protection facilities have continued to occur, which has put pressure on waste gas treatment in the hazardous waste industry. As a relatively mature waste gas treatment technology, the regenerative thermal incinerator (RTO) technology for industrial organic waste gas has high removal efficiency and energy saving. However, as an open flame equipment, in order to prevent explosion accidents, it has strict requirements on the concentration of incoming waste gas, which cannot be too high and the fluctuation cannot be too large. At the same time, the impurity content in the waste gas must also be effectively removed to prevent clogging of the heat storage bricks.

[0003] At present, the commonly used waste gas pretreatment processes include uniform air system, washing, filtration, cyclone sedimentation, etc. These pretreatment methods have good effects when dealing with fixed waste gas components and contents in the front-end air; however, the characteristics of the hazardous waste industry are: the hazardous wastes to be disposed of come from different industries and different manufacturers, and even if they come from the same manufacturer, the components of the materials at different production stages are also very different; this results in the conventional process being unable to achieve the expected pretreatment goals. In order to ensure production safety, hazardous waste manufacturers are forced to adopt waste gas treatment processes such as condensation and absorption to replace RTO treatment processes, which seriously restricts the healthy development of environmental protection management in the hazardous waste industry.

[0004] In view of this, a new process for incineration pretreatment of high-concentration waste gas in the hazardous waste industry is urgently needed to meet the needs of stable waste gas treatment in the hazardous waste industry, ensure the safe operation of environmental protection facilities, and adapt to the complex and changeable characteristics of hazardous waste gas from different sources, so as to improve the shortcomings of existing technologies. Summary of the invention

[0005] The purpose of the present invention is to provide a new process for pretreatment of high-concentration waste gas in the hazardous waste industry to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides a new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry, comprising the following steps: S1. Exhaust gas enters the liquid seal system: When the exhaust gas enters the liquid seal system, the exhaust gas concentration is measured and judged through the online monitoring equipment, and the exhaust gas is divided into high-concentration exhaust gas and low-concentration exhaust gas. In the early stage of driving, the composite liquid sealant is injected through the composite liquid sealant injection port; S2. Liquid seal system to treat waste gas: The liquid seal system is used to treat high-concentration waste gas and low-concentration waste gas in a targeted manner, so that the waste gas is within a safe concentration range when entering the subsequent RTO system for treatment; S3, vacuum analysis: When the composite liquid sealant reaches a saturated state during the treatment of high-concentration exhaust gas, the saturated state refers to the state where the dissolution of pollutants in the exhaust gas reaches its maximum capacity and the exhaust gas cannot be effectively treated, the vacuum analysis system is started, and the saturated composite liquid sealant is sent to the vacuum analysis system by a regeneration pump, and the dissolved exhaust gas components are recovered by a pressure reduction operation; S4, waste gas recovery and liquid sealant regeneration: The vacuum analysis system releases the waste gas components dissolved in the composite liquid sealant, and returns them to the front-end recovery system through the analysis gas for reprocessing. At the same time, the composite liquid sealant regenerated after vacuum analysis returns to the liquid sealant system through the regenerated composite liquid sealant recycling pipeline for continued use; S5, RTO system treatment: The treated waste gas enters the RTO waste gas incineration system for incineration treatment, realizing efficient treatment of high-concentration waste gas in the hazardous waste industry.

[0007] As a further improvement of the present technical solution, in S1, when the concentration of organic matter in the exhaust gas reaches above 10% LEL, it is regarded as high-concentration exhaust gas.

[0008] As a further improvement of the present technical solution, in S1, when the concentration of organic matter in the exhaust gas is lower than 5% LEL, it is regarded as low-concentration exhaust gas.

[0009] As a further improvement of the present technical solution, in S1, the composite liquid sealant includes ethylene glycol and diethylene glycol.

[0010] As a further improvement of the present technical solution, in S2, for high-concentration exhaust gas, the composite liquid sealing agent in the liquid sealing system dissolves part of the pollutants through physical dissolution.

[0011] As a further improvement of the present technical solution, in S2, for low-concentration exhaust gas, when it passes through the liquid sealing system, the volatiles of the composite liquid sealing agent will be entrained by the exhaust gas to increase the exhaust gas concentration.

[0012] As a further improvement of the present technical solution, in S2, the exhaust gas is in a safe concentration range of 5%LEL-10%LEL.

[0013] As a further improvement of the technical solution, in S5, the RTO waste gas incineration system uses incineration technology to treat the waste gas at high temperature, and the incineration temperature is between 800°C and 1100°C.

[0014] As a further improvement of the present technical solution, some of the pollutants include high-concentration organic compounds, sulfur-containing compounds, nitrogen-containing compounds, and high-viscosity and high-molecular-weight substances.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. In the new process of incineration pretreatment of high-concentration waste gas in the hazardous waste industry, the liquid sealing system can carry out targeted treatment according to the concentration of the waste gas, reduce the concentration of high-concentration waste gas, and increase the concentration of low-concentration waste gas, thereby improving the suitability of the waste gas entering the RTO system, reducing the natural gas consumption of the RTO system, and reducing energy costs. At the same time, it can effectively prevent the flame from returning when a flashback accident occurs, ensuring the safety of the front-end device area and eliminating secondary disasters. The unique composite liquid sealing agent can dissolve complex waste gas components, providing good conditions for subsequent treatment and improving the environmental protection of the entire treatment process.

[0016] 2. In the new process of incineration pretreatment of high-concentration waste gas in the hazardous waste industry, a separate vacuum analysis process is set up to promptly treat the composite liquid sealant when it is saturated, thereby achieving zero emission of waste gas and zero addition of composite liquid sealant, reducing pollution to the environment, and the synergistic effect of the liquid sealing system and the vacuum analysis process improves the efficiency and sustainability of the entire waste gas treatment process. In addition, the composite liquid sealant used is not a hazardous chemical and has a high boiling point. It is safe and stable during use and not easy to volatilize, which increases the stability of the liquid sealing system operation, thereby improving the safe production of hazardous waste treatment enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a flowchart of the waste gas incineration pretreatment process of the present invention; Figure 2 This is a flowchart of the waste gas incineration pretreatment steps of the present invention. DETAILED DESCRIPTION

[0018] The following will be combined with the accompanying drawings in 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0019] according to Figure 1 and Figure 2 As shown, the embodiment of the present invention also provides a new process for pre-treatment of high-concentration waste gas incineration in hazardous waste industry, comprising the following steps: Step 1: Exhaust gas enters the liquid seal system: according to Figure 1 As shown, in the exhaust gas ( Figure 1When the exhaust gas from the device area enters the liquid seal system, the exhaust gas concentration is measured and judged by online monitoring equipment, and the exhaust gas is divided into high-concentration exhaust gas and low-concentration exhaust gas. When the organic matter concentration in the exhaust gas reaches 10%LEL or more, it is regarded as high-concentration exhaust gas; when the organic matter concentration in the exhaust gas is lower than 5%LEL, it is regarded as low-concentration exhaust gas; This helps to improve the efficiency and safety of the entire exhaust gas treatment system and can be used in the early stage of start-up ( Figure 1 In the process of exhaust gas treatment, even in a high temperature environment, the composite liquid sealant is not easy to volatilize, which can ensure the stable operation of the liquid seal system and maintain the effective amount of the liquid sealant in the liquid seal system. At the same time, the ethylene glycol molecule contains hydroxyl group (-OH), which is hydrophilic and can dissolve the hydrophilic substances in the exhaust gas. At the same time, the carbon chain part in its molecular structure makes it soluble in some hydrophobic substances. The molecular structure of diethylene glycol is similar to that of ethylene glycol, but the carbon chain is longer, so it has stronger solubility in hydrophobic substances. After the two are mixed, they can dissolve both hydrophobic substances and hydrophilic substances in the exhaust gas, so that the exhaust gas can be effectively pretreated before entering the RTO system. In addition, ethylene glycol and diethylene glycol are stable in nature. They mainly treat various substances in the exhaust gas through physical dissolution. Under the normal conditions of exhaust gas pretreatment (temperature, pressure, etc.), no new chemical reaction products will be generated and no new exhaust gas impurities will be introduced; Step 2: Liquid seal system to treat waste gas: The liquid seal system is used to treat high-concentration waste gas and low-concentration waste gas. For high-concentration waste gas, the composite liquid sealant in the liquid seal system dissolves some pollutants through physical dissolution. Some pollutants include high-concentration organic compounds, sulfur-containing compounds, nitrogen-containing compounds, high-viscosity and high-molecular-weight substances. Among them, high-concentration organic compounds include benzene series, aldehydes, and ketones; buffering and concentration reduction of high-concentration waste gas are achieved. The physical dissolution of the composite liquid sealant not only reduces the waste gas concentration, but also stabilizes the flow and pressure of the waste gas, creating conditions for the stable treatment of the subsequent RTO system; for When low-concentration exhaust gas passes through the liquid seal system, the volatiles of the composite liquid sealant will be entrained by the exhaust gas, which is used to increase the exhaust gas concentration to a range that is more conducive to the RTO system's treatment. This not only helps to improve the treatment efficiency of the RTO system, but also reduces the consumption of natural gas and other energy sources during the treatment process of the RTO system, achieving energy conservation and emission reduction effects; the exhaust gas is kept in a safe concentration range when entering the subsequent RTO system for treatment. The safe concentration range of the exhaust gas is 5%LEL-10%LEL. At the same time, the liquid seal system can prevent the flame from returning to the front-end device area when a flashback occurs in the back-end RTO system, thereby ensuring system safety; Step 3: Vacuum analysis: When the composite liquid sealant reaches a saturated state in the process of treating high-concentration exhaust gas, the saturated state means that the dissolution of pollutants in the exhaust gas has reached its maximum capacity and the exhaust gas cannot be effectively treated, start the vacuum analysis system (according to Figure 1 As shown), using a regenerative pump (according to Figure 1 The saturated composite liquid sealant is sent to the vacuum analysis device (according to Figure 1 As shown in the figure), the dissolved waste gas components are recovered through the pressure reduction operation to achieve the regeneration of the composite liquid sealant and the recycling treatment of the waste gas, ensuring the efficiency and sustainability of the entire waste gas treatment process; Step 4: Waste gas recovery and liquid sealant regeneration: Vacuum analysis system (according to Figure 1 As shown in the figure, the waste gas components dissolved in the composite liquid sealant are released and returned to the front-end recovery system through the analytical gas (according to Figure 1 As shown in the figure, the composite liquid sealant is returned to the front end for reprocessing. At the same time, the composite liquid sealant regenerated after vacuum analysis is reused by regenerating the composite liquid sealant (according to Figure 1 The pipeline is returned to the liquid seal system for continued use, achieving zero exhaust gas emission and zero addition of composite liquid sealant; Step 5: RTO system treatment: The treated waste gas enters the RTO waste gas incineration system (according to Figure 1 The RTO waste gas incineration system uses incineration technology to treat waste gas at high temperature, and the incineration temperature is between 800℃-1100℃. At the same time, through the synergistic effect of the liquid seal system and the RTO system, the environmental protection and safety of the hazardous waste treatment process are improved. The liquid seal system effectively reduces the concentration fluctuation and flashback risk of waste gas in the pretreatment stage, and the RTO system finally treats the waste gas harmlessly, realizing the efficient treatment of high-concentration waste gas in the hazardous waste industry; The incineration temperature of the above-mentioned RTO waste gas incineration system is between 800℃-1100℃, which will not affect the normal use of the composite liquid sealant (ethylene glycol and diethylene glycol). This is mainly because: the composite liquid sealant plays a role in the liquid sealing system, and when the waste gas enters the RTO system for incineration treatment, it is a relatively independent stage from the liquid sealing system. During the waste gas treatment process, it is not easy to volatilize even in a high temperature environment, which can ensure the stable operation of the liquid sealing system.

[0020] In the present invention, first, when the exhaust gas enters the liquid sealing system, the high-concentration and low-concentration exhaust gases are distinguished through online monitoring equipment, which can not only carry out targeted treatment according to the exhaust gas concentration to improve the efficiency and safety of the entire exhaust gas treatment system, but also use the composite liquid sealing agent (ethylene glycol and diethylene glycol) to dissolve the hydrophobic and hydrophilic substances in the exhaust gas, so that the exhaust gas can be effectively pre-treated before entering the RTO system. At the same time, the liquid sealing system buffers and reduces the concentration of high-concentration exhaust gas and increases the concentration of low-concentration exhaust gas. For example, the composite liquid sealing agent dissolves part of the pollutants in the treatment of high-concentration exhaust gas, and entrains volatiles in the exhaust gas in the treatment of low-concentration exhaust gas, which effectively improves the treatment efficiency of the RTO system and reduces energy consumption.

[0021] The liquid sealing system can carry out targeted treatment according to the exhaust gas concentration, reduce the concentration of high-concentration exhaust gas, and increase the concentration of low-concentration exhaust gas, thereby improving the suitability of exhaust gas entering the RTO system, reducing the natural gas consumption of the RTO system, and reducing energy costs. At the same time, it can effectively prevent the flame from returning when a flashback accident occurs, ensuring the safety of the front-end device area and eliminating secondary disasters. The unique composite liquid sealing agent can dissolve complex exhaust gas components, providing good conditions for subsequent treatment and improving the environmental friendliness of the entire treatment process.

[0022] like Figure 1 As shown, a separate vacuum analysis process is adopted, and the composite liquid sealant can be treated in time when it is saturated, thereby achieving zero emission of waste gas and zero addition of composite liquid sealant, reducing pollution to the environment, and the synergistic effect of the liquid sealing system and the vacuum analysis process improves the efficiency and sustainability of the entire waste gas treatment process. In addition, the composite liquid sealant used is not a hazardous chemical and has a high boiling point. It is safe and stable during use and not easy to volatilize, which increases the stability of the liquid sealing system operation, thereby improving the safe production of hazardous waste treatment enterprises.

[0023] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry, characterized in that: The following steps are involved: S1. Exhaust gas enters the liquid seal system: When the exhaust gas enters the liquid seal system, the exhaust gas concentration is measured and judged through the online monitoring equipment, and the exhaust gas is divided into high-concentration exhaust gas and low-concentration exhaust gas. In the early stage of driving, the composite liquid sealant is injected through the composite liquid sealant injection port; S2. Liquid seal system to treat waste gas: The liquid seal system is used to treat high-concentration waste gas and low-concentration waste gas in a targeted manner, so that the waste gas is within a safe concentration range when entering the subsequent RTO system for treatment; S3, vacuum analysis: When the composite liquid sealant reaches a saturated state during the treatment of high-concentration exhaust gas, the saturated state refers to the state where the dissolution of pollutants in the exhaust gas reaches its maximum capacity and the exhaust gas cannot be effectively treated, the vacuum analysis system is started, and the saturated composite liquid sealant is sent to the vacuum analysis system by a regeneration pump, and the dissolved exhaust gas components are recovered by a pressure reduction operation; S4, waste gas recovery and liquid sealant regeneration: The vacuum analysis system releases the waste gas components dissolved in the composite liquid sealant, and returns them to the front-end recovery system through the analysis gas for reprocessing. At the same time, the composite liquid sealant regenerated after vacuum analysis returns to the liquid sealant system through the regenerated composite liquid sealant recycling pipeline for continued use; S5, RTO system treatment: The treated waste gas enters the RTO waste gas incineration system for incineration treatment, realizing efficient treatment of high-concentration waste gas in the hazardous waste industry.

2. The new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry according to claim 1 is characterized in that: In the above S1, when the concentration of organic matter in the exhaust gas reaches 10%LEL or more, it is regarded as high-concentration exhaust gas.

3. The new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry according to claim 1 is characterized in that: In S1, when the organic matter concentration in the exhaust gas is lower than 5% LEL, it is regarded as low-concentration exhaust gas.

4. The new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry according to claim 1 is characterized in that: In S1, the composite liquid sealant includes ethylene glycol and diethylene glycol.

5. The new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry according to claim 1 is characterized in that: In S2, for high-concentration exhaust gas, the composite liquid sealant in the liquid seal system dissolves part of the pollutants through physical dissolution.

6. The new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry according to claim 1 is characterized in that: In S2, for low-concentration exhaust gas, when it passes through the liquid sealing system, the volatiles of the composite liquid sealing agent will be entrained by the exhaust gas to increase the exhaust gas concentration.

7. The new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry according to claim 1 is characterized in that: In S2, the exhaust gas is in a safe concentration range of 5%LEL-10%LEL.

8. The new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry according to claim 1 is characterized in that: In S5, the RTO waste gas incineration system uses incineration technology to treat the waste gas at high temperature, and the incineration temperature is between 800°C and 1100°C.

9. The new process for pretreatment of high-concentration waste gas incineration in hazardous waste industry according to claim 5 is characterized in that: The pollutants include high concentrations of organic compounds, sulfur-containing compounds, nitrogen-containing compounds, and highly viscous and high molecular weight substances.

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