Multistage distributed low-boiling-point vocs combined adsorption box

Abstract

The application discloses a kind of multistage distributed low boiling point VOCs combination adsorption box, it is related to VOCs processing technical field, including box, core adsorption unit and auxiliary adsorption unit, multiple core adsorption units are arranged in box, auxiliary adsorption unit is arranged between core adsorption unit and box, core adsorption unit includes distribution pipe, molecular sieve buffer layer being arranged in distribution pipe, isolation screen layer being set in the outside of distribution pipe and carbon fiber layer being arranged between distribution pipe and isolation screen layer, each distribution pipe top end is connected cooling air inlet pipe, cooling air inlet pipe is connected with cold air gun, each distribution pipe bottom end is connected regeneration medium / waste gas inlet pipe, multiple through holes are provided on the outer circumferential surface of each distribution pipe, regeneration medium outlet pipe and waste gas outlet pipe are arranged at the top of box, and cooling air outlet pipe is arranged at the bottom of box.The application can reduce the cooling time after regeneration, improve adsorption effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of VOCs treatment, in particular to a multi-stage distributed low-boiling-point VOCs combined adsorption box. BACKGROUND

[0002] The most widely used technology for chemical waste gas at present is adsorption recovery technology. Although the effect of adsorption equipment for treating tail gas is greatly affected by the adsorbent, the internal structure of the adsorption device is directly related to the treatment efficiency of the adsorption device for tail gas. The existing adsorber already has a certain ability of VOCs adsorption and recovery. The basic idea of VOCs treatment is to consider how to recycle and reuse waste according to the resource properties and energy properties of VOCs volatile gas. The core principle of adsorption method for removing VOCs by using adsorber is that the adsorbent with large specific surface area and porous structure in the adsorber traps VOCs molecules. When the waste gas passes through the adsorption bed, VOCs are adsorbed in the pores, so that the gas is purified. The adsorber generally uses physical adsorption to control VOCs. The adsorption process is reversible. When the adsorption reaches saturation, water vapor can be used to desorb the adsorbent. After desorption, condensation and distillation are used to recover VOCs. The regenerated adsorbent can be recycled. The adsorption effect mainly depends on the properties of the adsorbent, the types and concentration of VOCs, and the operating temperature, humidity and pressure of the adsorption system.

[0003] The existing adsorber mainly has the following problems:

[0004] 1. The carbon fiber cools slowly after regeneration, and needs a long cooling time;

[0005] 2. The carbon fiber in the conventional adsorption box is not fully used during adsorption, and the adsorption is not complete, which reduces the adsorption effect. SUMMARY

[0006] The purpose of the present application is to provide a multi-stage distributed low-boiling-point VOCs combined adsorption box to solve the problems existing in the prior art and reduce the cooling time after regeneration and improve the adsorption effect.

[0007] To achieve the above purpose, the present application provides the following solutions:

[0008] The application provides a multi-stage distributed low-boiling VOCs combined adsorption box, which comprises a box body, core adsorption units and auxiliary adsorption units, a plurality of the core adsorption units are arranged in the box body, the auxiliary adsorption units are arranged between the core adsorption units and the box body, the core adsorption unit comprises a distribution pipe, a molecular sieve buffer layer arranged in the distribution pipe, an isolation screen layer sleeved outside the distribution pipe and a carbon fiber layer arranged between the distribution pipe and the isolation screen layer, the top end of each distribution pipe is connected with a cooling air inlet pipe, a cold air gun is connected to the cooling air inlet pipe, the bottom end of each distribution pipe is connected with a regeneration medium / waste gas inlet pipe, a plurality of through holes are arranged on the peripheral surface of each distribution pipe, a regeneration medium outlet pipe and a waste gas outlet pipe are arranged at the top of the box body, and a cooling air outlet pipe is arranged at the bottom of the box body.

[0009] Preferably, the bottom of the box body is also provided with a liquid seal U-shaped pipe, one end of the liquid seal U-shaped pipe is communicated with the inside of the box body, and the other end is communicated with the outside.

[0010] Preferably, the auxiliary adsorption unit is a high polymer adsorption material.

[0011] Preferably, the isolation screen layer is a metal material.

[0012] Preferably, the through holes are uniformly distributed on the peripheral surface of the distribution pipe.

[0013] Preferably, the top end and the bottom end of the distribution pipe are connected with the cooling air inlet pipe and the regeneration medium / waste gas inlet pipe through sleeve joints respectively.

[0014] Preferably, the box body is assembled by using a splicing type structure.

[0015] Compared with the prior art, the application has the following technical effects:

[0016] The application provides a multi-stage distributed low-boiling-point VOCs combined adsorption box, wherein VOCs waste gas enters a core adsorption unit from a regeneration medium / waste gas inlet pipe, a molecular sieve buffer layer preliminarily pretreats the waste gas, reduces the wind speed and makes the waste gas distribution more uniform, and then the waste gas is further adsorbed by an outer carbon fiber layer to ensure that the carbon fiber adsorption is complete, the residual VOCs are adsorbed by an auxiliary adsorption unit after the waste gas passes through the carbon fiber layer, the waste gas distribution is more uniform and the adsorption is more complete through the layer-by-layer buffering and adsorption of the waste gas, complete treatment of the low-boiling-point VOCs is realized, and the adsorption effect is improved. When the carbon fiber layer is regenerated, the regeneration medium is introduced into the core adsorption unit through the regeneration medium / waste gas inlet pipe to desorb and regenerate the carbon fiber layer, and the VOCs are recovered through subsequent treatment after desorption; after desorption, cooling is performed, and the cooling wind enters the distribution pipe after being cooled by the cold air gun, and each part is cooled from the inside to the outside, and the cooling time after regeneration is reduced by multiple distribution of the cold air in the cold air gun. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings described below only show some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort.

[0018] Figure 1 The application provides a multi-stage distributed low-boiling-point VOCs combined adsorption box structure diagram.

[0019] Figure 2 The application provides a multi-stage distributed low-boiling-point VOCs combined adsorption box structure diagram.

[0020] Figure 3 The application provides a multi-stage distributed low-boiling-point VOCs combined adsorption box structure diagram.

[0021] Figure 4 The application provides a multi-stage distributed low-boiling-point VOCs combined adsorption box structure diagram.

[0022] In the figure: 1-box, 2-core adsorption unit, 3-auxiliary adsorption unit, 4-distribution pipe, 5-molecular sieve buffer layer, 6-isolation screen layer, 7-carbon fiber layer, 8-cooling wind inlet pipe, 9-cold air gun, 10-regeneration medium / waste gas inlet pipe, 11-through hole, 12-regeneration medium outlet pipe, 13-waste gas outlet pipe, 14-cooling wind outlet pipe, 15-liquid seal U-shaped pipe, 16-sleeve. DETAILED DESCRIPTION

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] The purpose of this invention is to provide a multi-stage distributed low-boiling-point VOCs combined adsorption box to solve the problems existing in the prior art, thereby reducing the cooling time after regeneration and improving the adsorption effect.

[0025] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] like Figures 1-4 As shown, this embodiment provides a multi-stage distributed low-boiling-point VOCs combined adsorption box, including a box body 1, a core adsorption unit 2, and an auxiliary adsorption unit 3. Multiple core adsorption units 2 are arranged inside the box body 1, and auxiliary adsorption units 3 are arranged between the core adsorption units 2 and the box body 1. The core adsorption unit 2 includes a distribution pipe 4, a molecular sieve buffer layer 5 arranged inside the distribution pipe 4, an isolation screen layer 6 sleeved outside the distribution pipe 4, and a carbon fiber layer 7 arranged between the distribution pipe 4 and the isolation screen layer 6. The top of each distribution pipe 4 is connected to a cooling air inlet pipe 8, and a cold air gun 9 is connected to the cooling air inlet pipe 8. The bottom of each distribution pipe 4 is connected to a regeneration medium / exhaust gas inlet pipe 10. Multiple through holes 11 are provided on the outer circumferential surface of each distribution pipe 4. A regeneration medium outlet pipe 12 and an exhaust gas outlet pipe 13 are arranged at the top of the box body 1, and a cooling air outlet pipe 14 is arranged at the bottom of the box body 1.

[0027] When the adsorption is carried out, the VOCs waste gas enters the core adsorption unit 2 through the regeneration medium / waste gas inlet pipe 10, the molecular sieve buffer layer 5 preliminarily pre-processes the waste gas, reduces the wind speed, and makes the waste gas distribution more uniform, and then the outer carbon fiber layer 7 further adsorbs the waste gas, ensures that the carbon fiber is fully applied during adsorption, and the residual VOCs passes through the carbon fiber layer 7 and is adsorbed by the auxiliary adsorption unit 3, so that the waste gas is more uniformly distributed and more fully adsorbed, the complete treatment of low-boiling-point VOCs is realized, the adsorption effect is improved, and after the adsorption is completed, the waste gas is discharged through the waste gas outlet pipe 13. When the carbon fiber layer 7 is regenerated, the regeneration medium is introduced into the core adsorption unit 2 through the regeneration medium / waste gas inlet pipe 10 to desorb and regenerate the carbon fiber layer 7, and after desorption, the regeneration medium is discharged through the regeneration medium outlet pipe 12, and then the VOCs are recovered after post-processing; after desorption, cooling is carried out, the cooling air enters the distribution pipe 4 after being cooled by the cold air gun 9, and the cooling air is cooled from the inside to the outside, and the cooling air is discharged from the bottom cooling air outlet pipe 14. By distributing the cold air in the cold air gun 9 multiple times, the cooling time after regeneration is reduced.

[0028] The regeneration medium can be hot nitrogen or steam, and hot nitrogen is preferred. Most activated carbons have hydrophobicity, but because water vapor has a higher relative pressure and a smaller molecular weight than VOCs, water vapor is more easily diffused and preferentially adsorbed by the activated carbon column. The adsorption column outlet gas concentration measurement results obtained by the thermal conductivity detector show that water vapor penetrates the adsorption column first and leaves a highest point on the breakthrough curve. Therefore, in the binary competitive adsorption of VOCs, water vapor and activated carbon, the adsorption of water vapor dominates. The binary adsorption equilibrium of VOCs, water vapor and activated carbon can be simplified as follows: (1) water vapor is preferentially adsorbed on activated carbon; (2) VOCs are adsorbed on activated carbon that has adsorbed water vapor, and part of the water is replaced. When desorption is carried out by selecting hot nitrogen, there is no problem of high humidity. The nitrogen in the desorption system is heated to the required desorption temperature by the heater and then enters the core adsorption unit 2 for reverse desorption. The desorbed gas is condensed by the condenser for recovery, and the uncondensed gas is sent back to the heater by the circulating fan for heating and desorption again. The adsorption capacity of the substance decreases with the increase of temperature, and the temperature of the adsorbent is increased to make the adsorbed components desorb, which is also called temperature swing desorption.

[0029] The core adsorption unit 2 and the box body adopt a detachable sleeve structure, which is convenient for maintenance and replacement.

[0030] In the embodiment, the bottom of the box body 1 is further provided with a liquid seal U-shaped pipe 15, one end of the liquid seal U-shaped pipe 15 is communicated with the inside of the box body 1, and the other end is communicated with the outside. In the desorption stage, the waste liquid generated by the steam can be discharged through the liquid seal U-shaped pipe 15, which can ensure the sealing of the equipment and discharge the waste liquid at the same time.

[0031] In the embodiment, the auxiliary adsorption unit 3 is a high polymer adsorption material, and the adsorption effect on VOCs is good.

[0032] In the embodiment, the isolation screen layer 6 is a metal material, preferably 304 stainless steel, which is corrosion resistant.

[0033] In the embodiment, the through holes 11 are uniformly distributed on the outer peripheral surface of the distribution pipe 4, so that the waste gas is more evenly distributed.

[0034] In the embodiment, the top end and the bottom end of the distribution pipe 4 are connected to the cooling air inlet pipe 8 and the regeneration medium / waste gas inlet pipe 10 through the sleeve opening 16 respectively, and the sleeve opening is used for connection, which is convenient and fast to install.

[0035] In the embodiment, the box body 1 is assembled by splicing, the number of box bodies can be selected according to the air volume and concentration, the installation mode is more convenient, and the selection of the equipment is more flexible.

[0036] In the application, specific examples are applied to explain the principles and implementation modes of the application, and the above embodiment is only used to help understand the method and core idea of the application; meanwhile, for the general skilled in the art, according to the idea of the application, the specific implementation mode and application range will be changed. In conclusion, the content of the specification should not be understood as the limitation of the application.

Claims

1. A multi-stage distributed low boiling point VOCs combined adsorption tank, characterized in that: The application relates to a box, a core adsorption unit and an auxiliary adsorption unit, a plurality of the core adsorption units are arranged in the box, the auxiliary adsorption unit is arranged between the core adsorption unit and the box, the core adsorption unit comprises a distribution pipe, a molecular sieve buffer layer arranged in the distribution pipe, an isolation screen layer sleeved outside the distribution pipe and a carbon fiber layer arranged between the distribution pipe and the isolation screen layer, the top end of each distribution pipe is connected with a cooling air inlet pipe, a cold air gun is connected to the cooling air inlet pipe, the bottom end of each distribution pipe is connected with a regeneration medium / waste gas inlet pipe, a plurality of through holes are arranged on the outer circumferential surface of each distribution pipe, the through holes are uniformly distributed on the outer circumferential surface of the distribution pipe, a regeneration medium outlet pipe and a waste gas outlet pipe are arranged at the top of the box, and a cooling air outlet pipe is arranged at the bottom of the box.

2. The multi-stage distributed low boiling point VOCs combined adsorption box according to claim 1, characterized in that: The bottom of the box is also provided with a liquid seal U-shaped pipe, one end of the liquid seal U-shaped pipe is communicated with the inside of the box, and the other end is communicated with the outside.

3. The multi-stage distributed low boiling point VOCs combined adsorption box according to claim 1, characterized in that: The auxiliary adsorption unit is a high polymer adsorption material.

4. The multi-stage distributed low boiling point VOCs combined adsorption box according to claim 1, characterized in that: The isolation screen layer is a metal material.

5. The multi-stage distributed low boiling point VOCs combined adsorption box according to claim 1, characterized in that: The top end and the bottom end of the distribution pipe are connected with the cooling air inlet pipe and the regeneration medium / waste gas inlet pipe through sleeve joints respectively.

6. The multi-stage distributed low boiling point VOCs combined adsorption box according to claim 1, characterized in that: The box is assembled by using a splicing type structure.

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