Recycling treatment system for low-water-dew-point organic waste gas

Abstract

The utility model relates to a low-water-dew-point organic waste gas recycling treatment system which comprises a drying oven, a waste heat recycling system and a condensation system. The condensation system comprises a gas-liquid separator. High-temperature waste gas sequentially enters the waste heat recovery system and the condensation system from the drying oven to be cooled and is subjected to gas-liquid separation through the gas-liquid separator, and separated gas returns to the waste heat recovery system to be subjected to heat recovery and finally returns to the drying oven. High-temperature waste gas exhausted from the drying oven is cooled many times through the waste heat recovery system and the condensation system, organic matter in the waste gas is condensed in the condensation system, gas-liquid separation is conducted through the gas-liquid separator, and the waste gas with most organic solvents removed returns to the waste heat recovery system to recover heat and finally returns to the drying oven. In this way, the waste gas which is low in water content and recycled is obtained, the energy consumption of subsequent purification treatment of the solvent is reduced, recycling of the high-temperature low-water-content air is achieved, and the dehumidification energy consumption and the heating energy consumption are reduced.

Description

Technical Field

[0001] The present application relates to the technical field of organic waste gas recovery systems, and in particular to a recycling and recovery treatment system for low-water-dew-point organic waste gas. Background Art

[0002] In the prior art, the production of some products (such as solid electrolytes for semi-solid batteries and solid-state batteries) requires strict control of the moisture content. Therefore, when it is necessary to dry the organic solvents in these products (such as small molecular aromatics, esters, alkanes, ethers and ketones), they must either be removed by vacuum drying or dehumidified air must be continuously produced to carry them out. For the process of carrying organic solvents out with dehumidified air, the waste gas generated by drying is usually recovered by condensation, adsorption, or absorption with other solvents. For direct adsorption, the concentration of low-concentration waste gas can be increased, but after desorption, it must eventually be recovered by condensation recovery and solvent absorption. The current process has the following problems:

[0003] 1) For processes using other solvents for absorption, the recovered organic solvent is mixed with a large amount of other types of solvents, which increases the energy consumption cost and equipment investment for purification;

[0004] 2) For the process of adsorption followed by desorption, the existing treatment method is to use steam for desorption, which not only brings water into the recovered solvent, increasing the difficulty of subsequent purification, but also leads to the generation of wastewater; due to the use of water desorption, there is residual moisture in the adsorber, resulting in the low dew point air cannot be recycled, and directly discharged into the atmosphere increases the cost of dehumidification; the desorbed steam needs to be cooled and condensed by cooling water and chilled water instead of recovering the heat therein, and because the latent heat of condensation of water vapor is large and more steam needs to be condensed, the system consumes more energy during operation. Utility Model Content

[0005] Based on this, it is necessary to provide a recycling and recovery treatment system for low water dew point organic waste gas, including a drying oven, a waste heat recovery system, and a condensation system, wherein the condensation system includes a gas-liquid separator;

[0006] The high-temperature exhaust gas from the drying oven sequentially enters the waste heat recovery system and the condensation system for cooling, and passes through the gas-liquid separator for gas-liquid separation. The separated gas returns to the waste heat recovery system for heat recovery, and finally returns to the drying oven.

[0007] The waste heat recovery system includes primary waste heat recovery and secondary waste heat recovery, and both the primary waste heat recovery and the secondary waste heat recovery include heat exchangers; the drying oven, the primary waste heat recovery, the secondary waste heat recovery, and the condensation system are connected in sequence.

[0008] It also includes a circulating fan and an adsorption module for adsorbing organic matter. One end of the circulating fan is connected to the secondary waste heat recovery, and the other end of the circulating fan is respectively connected to the primary waste heat recovery and the adsorption module. The adsorption module is connected to an external exhaust channel, and the primary waste heat recovery is connected to the drying oven.

[0009] The adsorption module includes a zeolite molecular sieve rotor or an activated carbon adsorption tank.

[0010] The drying oven is connected to an external exhaust fan and a return air fan, the primary waste heat recovery includes an air inlet and an air outlet, the external exhaust fan is connected to the air inlet of the primary waste heat recovery, and the return air fan is connected to the air outlet of the primary waste heat recovery.

[0011] It also includes a nitrogen heater and a nitrogen buffer tank into which nitrogen can be flushed, and two ends of the nitrogen buffer tank are respectively connected to the waste heat recovery system and the adsorption module.

[0012] A nitrogen circulation fan and a nitrogen heater are connected between the nitrogen buffer tank and the adsorption module.

[0013] The adsorption module, the waste heat recovery system, the nitrogen buffer tank, the nitrogen circulation fan, and the nitrogen heater are connected in sequence to form a closed loop connection.

[0014] Compared with the prior art, the advantages of the utility model are:

[0015] The utility model provides a recycling and recovery treatment system for low-water-dew-point organic waste gas, which cools down the high-temperature waste gas discharged from a drying oven multiple times through a waste heat recovery system and a condensation system, condenses the organic matter in the waste gas in the condensation system, and separates the gas and liquid through a gas-liquid separator, removes most of the waste gas from the organic solvent and returns to the waste heat recovery system to recover heat, and finally returns to the drying oven, thereby obtaining waste gas with low water content and recycled, reducing the energy consumption of subsequent purification treatment of the solvent, realizing the recycling of high-temperature and low-water-content air, and reducing dehumidification energy consumption and heating energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application 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 application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 This is a schematic flow chart of a recycling and recovery system for treating low water dew point organic waste gas according to an embodiment of the present application. DETAILED DESCRIPTION

[0018] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0019] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0020] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0021] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed 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 elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0022] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0023] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0024] A recycling and recovery treatment system for low-water-dew-point organic waste gas comprises a drying oven, a waste heat recovery system, and a condensation system, wherein the condensation system comprises a gas-liquid separator; the drying oven, the waste heat recovery system, and the condensation system are connected in sequence, and the high-temperature waste gas enters the waste heat recovery system and the condensation system from the drying oven in sequence for cooling, and the organic matter in the waste gas is condensed in the condensation system, and then passes through the gas-liquid separator for gas-liquid separation, and the separated gas returns to the waste heat recovery system for heat recovery, and finally returns to the drying oven, thereby realizing waste gas circulation, and the waste gas returned to the drying oven has a low water content.

[0025] The recycling and recovery treatment system for low-water dew-point organic waste gas uses a waste heat recovery system and a condensation system to cool the high-temperature waste gas discharged from the drying oven multiple times. The organic matter in the waste gas is condensed in the condensation system and separated into gas and liquid by a gas-liquid separator. The waste gas with most of the organic solvent removed returns to the waste heat recovery system to recover heat, and finally returns to the drying oven, so that waste gas with low water content and recycled use is obtained, the energy consumption of subsequent solvent purification treatment is reduced, the recycling of high-temperature and low-water content air is realized, and the dehumidification energy consumption and heating energy consumption are reduced.

[0026] In the utility model, the waste heat recovery system includes primary waste heat recovery and secondary waste heat recovery, both of which include a heat exchanger (the heat exchanger is the prior art); the drying oven, the primary waste heat recovery, the secondary waste heat recovery, and the condensation system are connected in sequence, and the high-temperature waste water discharged from the drying oven enters the condensation system for the third cooling after two stages of waste heat recovery, so that the organic matter in the waste water is condensed in the condensation system, thereby separating the organic matter in the waste gas.

[0027] The utility model also includes a circulating fan and an adsorption module for adsorbing organic matter. One end of the circulating fan is connected to the secondary waste heat recovery, and the other end of the circulating fan is respectively connected to the primary waste heat recovery and the adsorption module. The adsorption module is connected to the external discharge channel, and the primary waste heat recovery is connected to the drying oven. The waste gas separated by the gas-liquid separator returns to the secondary waste heat recovery and is divided into two parts by the circulating fan. One part enters the primary waste heat recovery for heat recovery and then enters the drying oven for recycling; the other part enters the adsorption module. The adsorption module includes a zeolite molecular sieve rotor or an activated carbon adsorption tank. The organic matter in the waste gas is further adsorbed by the zeolite molecular sieve rotor or the activated carbon adsorption tank. After the waste gas meets the standards, it can be discharged through the tail exhaust fan.

[0028] In the utility model, the drying oven is connected with an external exhaust fan and a return air fan, and the first-level waste heat recovery includes an air inlet and an air outlet. The external exhaust fan is connected with the air inlet of the first-level waste heat recovery, and the return air fan is connected with the air outlet of the first-level waste heat recovery. The high-temperature gas discharged from the drying oven enters the first-level waste heat recovery through the external exhaust fan, and a part of the waste gas returning to the waste heat recovery system from the condensing main unit returns to the drying oven through the return air fan.

[0029] The utility model also includes a nitrogen heater and a nitrogen buffer tank into which nitrogen can be flushed. The two ends of the nitrogen buffer tank are connected to the waste heat recovery system and the adsorption module respectively. A nitrogen circulation fan and a nitrogen heater are connected between the nitrogen buffer tank and the adsorption module. When the zeolite molecular sieve rotor adsorption or the activated carbon adsorption tank is saturated with adsorption, high-temperature hot nitrogen is used to purge the saturated part of the rotor or the saturated activated carbon tank. The desorbed high-organic content and high-temperature nitrogen is heat-exchanged with the low-temperature nitrogen discharged from the condensation main unit through the waste heat recovery heat exchanger to reduce the temperature, and then enters the condensation main unit for condensation. The saturated rotor or activated carbon adsorption tank uses nitrogen for desorption, and no waste water is generated. The waste heat recovery system, nitrogen buffer tank, nitrogen circulation fan, nitrogen heater, and adsorption module are connected in sequence and form a closed loop, so that the desorbed hot nitrogen can be recycled, and the use cost is low.

[0030] The low-temperature medium used by the condensing host to cool the exhaust gas includes low-temperature water, salt water, refrigerant, low-temperature heat transfer oil, etc. In order to prevent some organic matter from frosting in the condensing host when the temperature is low, multiple condensing hosts (that is, condensing systems) can be connected in parallel. When one of them frosts and affects the heat transfer efficiency, it is switched to another one to continue cooling and condensing the exhaust gas.

[0031] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A recycling and treatment system for low water dew point organic waste gas, characterized in that: It includes a drying oven, a waste heat recovery system, and a condensation system, wherein the condensation system includes a gas-liquid separator; The high-temperature exhaust gas from the drying oven sequentially enters the waste heat recovery system and the condensation system for cooling, and passes through the gas-liquid separator for gas-liquid separation. The separated gas returns to the waste heat recovery system for heat recovery, and finally returns to the drying oven.

2. The recycling and treatment system for low water dew point organic waste gas according to claim 1 is characterized in that: The waste heat recovery system includes primary waste heat recovery and secondary waste heat recovery, and both the primary waste heat recovery and the secondary waste heat recovery include heat exchangers; the drying oven, the primary waste heat recovery, the secondary waste heat recovery, and the condensation system are connected in sequence.

3. The recycling and treatment system for low water dew point organic waste gas according to claim 2 is characterized in that: It also includes a circulating fan and an adsorption module for adsorbing organic matter. One end of the circulating fan is connected to the secondary waste heat recovery, and the other end of the circulating fan is respectively connected to the primary waste heat recovery and the adsorption module. The adsorption module is connected to an external exhaust channel, and the primary waste heat recovery is connected to the drying oven.

4. The recycling and treatment system for low water dew point organic waste gas according to claim 3 is characterized in that: The adsorption module includes a zeolite molecular sieve rotor or an activated carbon adsorption tank.

5. The recycling and treatment system for low water dew point organic waste gas according to claim 2 is characterized in that: The drying oven is connected to an external exhaust fan and a return air fan, the primary waste heat recovery includes an air inlet and an air outlet, the external exhaust fan is connected to the air inlet of the primary waste heat recovery, and the return air fan is connected to the air outlet of the primary waste heat recovery.

6. The recycling and treatment system for low water dew point organic waste gas according to claim 3 is characterized in that: It also includes a nitrogen heater and a nitrogen buffer tank into which nitrogen can be flushed, and two ends of the nitrogen buffer tank are respectively connected to the waste heat recovery system and the adsorption module.

7. The recycling and treatment system for low water dew point organic waste gas according to claim 6 is characterized in that: A nitrogen circulation fan and a nitrogen heater are connected between the nitrogen buffer tank and the adsorption module.

8. The recycling and treatment system for low water dew point organic waste gas according to claim 7 is characterized in that: The adsorption module, the waste heat recovery system, the nitrogen buffer tank, the nitrogen circulation fan, and the nitrogen heater are connected in sequence to form a closed loop connection.

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