Device for absorbing THF-containing waste gas by using GBL
By combining GBL absorbent and vacuum distillation column, the problems of low product yield, high energy consumption, and difficult azeotropic separation in THF emission treatment have been solved, achieving efficient absorption and recovery of THF, reducing energy consumption and waste liquid generation, and improving economic and environmental benefits.
Patent Information
- Application Number
- CN202520078140.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-14
- Publication Date
- 2026-01-30
- Estimated Expiration
- 2035-01-14
AI Technical Summary
Existing technologies for the emission control and treatment of THF have problems such as reduced product yield, increased raw material consumption, high energy consumption, and difficulty in separating azeotropic substances. In particular, when THF azeotropically reacts with methanol in THF-containing wastewater, conventional distillation methods are difficult to separate them effectively.
Using GBL as the absorbent, a combination of a THF absorption tower and a THF distillation tower is used to increase the mass transfer area. By utilizing the difference in azeotropic points between GBL and THF, combined with vacuum distillation technology and heat recovery design, efficient absorption and desorption of THF are achieved, and the GBL absorbent can be reused.
It improves the absorption and recovery rate of THF, reduces energy consumption and waste liquid generation, enhances economic and environmental benefits, and achieves efficient separation and recovery of THF.
Smart Images
Figure CN223846603U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to gas absorption treatment technical field especially is with a device that utilizes GBL to the waste gas containing THF is absorbed. BACKGROUND
[0002] In the chemical production process, the emission of volatile organic compounds (VOCs) is an important problem. These compounds not only pollute the environment, but also harm human health. Therefore, controlling and treating VOCs emissions is one of the important tasks in the field of environmental protection. Among them, tetrahydrofuran (THF) is a common VOC, which has a wide application in chemical production. However, the emission control and treatment of THF faces many challenges.
[0003] At present, the emission treatment of THF usually adopts absorption method. This method is to contact the waste gas containing THF with the absorbent, so that THF is absorbed by the absorbent, so as to separate THF from the waste gas. Common absorbents include water, alcohol and the like.
[0004] However, there are the following problems to be solved urgently:
[0005] (1) THF absorbed by the adsorbent cannot be further effectively separated and recovered, so that for THF as product or main raw material, the product yield is reduced or the raw material consumption is increased, and the generated THF-containing wastewater also causes the increase of three wastes;
[0006] (2) When treating waste gas containing THF, the process energy consumption and cost are high, which greatly limits its application.
[0007] (3) Because THF, alcohol and water can easily form azeotrope, the separation is difficult, especially when the wastewater contains methanol with close azeotropic point with THF, the conventional rectification method is difficult to treat the wastewater and separate THF therein. SUMMARY
[0008] The purpose of the utility model is to overcome the defects of the prior art and provide a device for absorbing waste gas containing THF by using GBL.
[0009] The purpose of the utility model can be realized by the following technical scheme:
[0010] The technical scheme of the utility model provides a device for absorbing waste gas containing THF by using GBL, which comprises a THF absorption tower, a feed preheater, a THF rectification tower and a gas phase condenser, wherein,
[0011] The THF absorption tower is provided with a GBL adsorbent inlet at the upper part of the filler, a THF-containing waste gas inlet at the lower part of the filler, and a tower kettle outlet at the bottom, the tower kettle outlet is connected with the first heat exchange inlet of the feed preheater,
[0012] The THF rectification tower comprises segmented fillers arranged in the vertical direction, a first THF rectification tower inlet arranged between the segmented fillers, a second THF rectification tower inlet arranged at the upper part of the segmented fillers, and a first THF rectification tower outlet arranged at the top, the first THF rectification tower inlet is connected with the first heat exchange outlet of the feed preheater, the first THF rectification tower outlet is connected with the gas phase condenser, and the outlet of the gas phase condenser is respectively connected with the second THF rectification tower inlet and the THF recovery position.
[0013] Therefore, the GBL adsorbent and the THF-containing waste gas are mixed in the THF absorption tower to obtain GBL absorption liquid for absorbing THF, and after being preheated by the feed preheater, the GBL absorption liquid for absorbing THF enters the THF rectification tower to complete the separation of GBL and THF.
[0014] In some specific embodiments, the bottom of the THF rectification tower is provided with a second THF rectification tower outlet, the second THF rectification tower outlet is connected with the second heat exchange inlet of the feed preheater, so that the liquid phase flowing from the THF rectification tower to the feed preheater can exchange heat with the GBL absorption liquid for absorbing THF.
[0015] In some specific embodiments, the second heat exchange outlet of the feed preheater is further connected with a cooler, and the cooler is connected with the THF absorption tower, so that the liquid phase flowing from the THF rectification tower to the feed preheater is cooled by the cooler and then reenters the THF absorption tower to absorb the THF-containing waste gas.
[0016] In some specific embodiments, the THF absorption tower is further provided with a GBL adsorbent recycling inlet at the upper part of the filler, and the GBL adsorbent recycling inlet is connected with the cooler.
[0017] In some specific embodiments, the tower kettle outlet of the absorption tower is in communication with a channel from the second heat exchange outlet of the feed preheater to the cooler.
[0018] In some specific embodiments, the tower kettle pump is arranged at the tower kettle outlet of the absorption tower, and the rectification tower kettle pump is arranged at the second THF rectification tower outlet.
[0019] In some specific embodiments, a reflux pump is arranged at the outlet of the gas phase condenser, so that the gas phase condensation product is refluxed to the THF rectification tower and the THF recovery position by the reflux pump, respectively.
[0020] In some specific embodiments, a THF recovery tank is also provided between the vapor phase condenser and the reflux pump.
[0021] In some specific embodiments, the THF distillation column is provided with two sections of packing material of equal height.
[0022] In some specific embodiments, the THF distillation column is a vacuum distillation column, which is equipped with a siphon-type reboiler.
[0023] Compared with the prior art, the present invention has the following beneficial effects:
[0024] (1) This utility model increases the mass transfer area between the GBL absorbent and the THF-containing waste gas by using a THF absorption tower, thereby maximizing the absorption rate of THF by the GBL absorbent. This allows the THF-containing tail gas to be absorbed in a single process, and the remaining inert gas meets the environmental protection requirements for direct discharge into the atmosphere, reducing equipment energy consumption and overall environmental benefits.
[0025] (2) This utility model adopts a uniquely designed vacuum distillation technology, which uses a vacuum packed distillation column to desorb and distill THF in the GBL absorbent. The quality of the THF obtained by distillation meets the requirements for continued recycling. While reducing the heat load of the distillation column, the utilization rate of the THF raw material that was originally wasted is maximized, thus improving the economic efficiency of the equipment from the perspective of raw materials.
[0026] (3) This utility model utilizes the desorbed GBL material to continue to be used as an absorbent and returned to the absorption tower, realizing the efficient reuse of the absorbent, reducing the generation of waste liquid, and improving the overall economic benefits while improving environmental protection benefits.
[0027] (4) By optimizing the heat recovery design, this utility model realizes the effective recovery and reuse of heat in the two processes of absorption and desorption, thereby reducing the overall energy consumption once again. Attached Figure Description
[0028] Figure 1 This is a schematic diagram of the structure of this utility model.
[0029] The diagram is labeled as follows:
[0030] 1 is the THF absorber, 2 is the cooler, 3 is the feed preheater, 4 is the THF distillation column, 5 is the vapor phase condenser, 6 is the THF recovery tank, 7 is the reflux pump, 8 is the absorber bottom pump, and 9 is the distillation column bottom pump. Detailed Implementation
[0031] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.
[0032] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.
[0033] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.
[0034] In the following embodiments, unless otherwise specified, the functional components or structures are conventional components or structures used in the art to achieve the corresponding functions.
[0035] Example 1:
[0036] like Figure 1 The diagram shows a device for absorbing THF-containing waste gas using GBL, comprising a THF absorption tower 1, a feed preheater 3, a THF distillation tower 4, and a vapor-phase condenser 5.
[0037] The THF absorption tower 1 is equipped with a GBL adsorbent inlet located at the top of the packing, a THF-containing waste gas inlet located at the bottom of the packing, and an absorption tower bottom outlet located at the bottom. The absorption tower bottom outlet is connected to the first heat exchange inlet of the feed preheater 3.
[0038] The THF distillation column 4 includes segmented packing arranged vertically, a first THF distillation column inlet located between the segmented packing, a second THF distillation column inlet located above the segmented packing, and a first THF distillation column outlet located at the top. The first THF distillation column inlet is connected to the first heat exchange outlet of the feed preheater 3, and the first THF distillation column outlet is connected to the vapor phase condenser 5. The outlet of the vapor phase condenser 5 is connected to the second THF distillation column inlet and the THF recovery point, respectively.
[0039] Thus, the GBL adsorbent and the THF-containing waste gas are mixed in the THF absorption tower 1 to obtain the GBL absorbent liquid that absorbs THF. The bottom of the absorption tower is discharged as waste, and the GBL that absorbs THF is discharged from the bottom of the absorption tower. After being preheated by the feed preheater 3, the GBL that absorbs THF enters the THF distillation tower 4 to complete the separation of GBL and THF.
[0040] In the technical solution, firstly, GBL (gamma-butyrolactone) is used as an adsorbent, compared with the traditional water absorbent, the azeotropic point difference of GBL and THF, methanol and other azeotropes is large, which can effectively avoid the formation of azeotropes, reduce the separation difficulty of THF, methanol from the absorbent in the subsequent separation. Secondly, a specially designed THF absorption tower 1 is used, which increases the mass transfer area of THF-containing waste gas and GBL adsorbent, maximizes the absorption rate of GBL adsorbent to THF, so that the THF-containing waste gas can be completed through one absorption process, the remaining inert gas meets the environmental protection requirement of direct discharge into the atmosphere, and the equipment energy consumption and overall environmental protection benefit are reduced. Thirdly, THF in the GBL absorption liquid is desorbed and rectified by using the THF rectifying tower 4, and the quality of the THF rectified can meet the index requirements of further recycling, which reduces the heat load of the THF rectifying tower 4 and improves the utilization rate of the originally wasted THF raw material to the extreme, thereby improving the economic benefit of the device from the raw material.
[0041] More specifically, the bottom of the THF rectifying tower 4 is provided with a second THF rectifying tower outlet, which is connected to the second heat exchange inlet of the feed preheater 3, so that the liquid phase flowing from the THF rectifying tower 4 to the feed preheater 3 can exchange heat with the GBL adsorbent that has absorbed THF. Through the optimization of heat recovery design, the heat of the desorption process is effectively recovered and reused, and the overall energy consumption is reduced.
[0042] The second heat exchange outlet of the feed preheater 3 is also connected to the cooler 2, and the cooler 2 is connected to the THF absorption tower 1, so that the liquid phase flowing from the THF rectifying tower 4 into the feed preheater 3 is cooled by the cooler 2 and then reenters the THF absorption tower 1 to absorb the THF-containing waste gas. The desorbed GBL material is returned to the THF absorption tower 1 as an adsorbent, which realizes efficient reuse of the adsorbent, reduces the generation of waste liquid, improves the environmental protection benefit, and improves the economic benefit. At the same time, through the optimization of heat recovery design, the heat of the absorption and desorption processes is effectively recovered and reused, and the overall energy consumption is reduced again.
[0043] The THF absorption tower 1 is also provided with a GBL adsorbent reuse inlet on the upper part of the filler, which is connected to the cooler 2.
[0044] The absorption tower tank outlet is connected to the cooler 2, and exemplarily, the absorption tower tank outlet is in communication with the channel from the second heat exchange outlet of the feed preheater 3 to the cooler 2.
[0045] The absorption tower tank outlet is provided with an absorption tower tank pump 8, and the second THF rectifying tower outlet is provided with a rectifying tower tank pump 9.
[0046] The outlet of the gas phase condenser 5 is provided with a reflux pump 7 to return the gas phase condensation product to the THF rectification tower 4 and the THF recovery device respectively through the reflux pump 7.
[0047] The THF recovery tank 6 is further provided between the gas phase condenser 5 and the reflux pump 7.
[0048] Two segments of isohigh packing are provided in the THF rectification tower 4.
[0049] The THF rectification tower 4 is a vacuum rectification tower, and a siphon type reboiler is provided in the THF rectification tower 4. The siphon type reboiler uses low-pressure steam as a heat source to evaporate THF in the GBL adsorption liquid to provide mass transfer power for the entire THF rectification tower 4, so as to realize the rectification and separation process of THF and GBL.
[0050] The use steps of the device are as follows:
[0051] (1) First, the THF-containing waste gas enters the THF absorption tower 1 from the THF-containing waste gas inlet located below the packing of the THF absorption tower 1, and the GBL adsorbent enters the THF absorption tower 1 from the GBL adsorbent inlet located above the packing of the THF absorption tower 1, so as to absorb THF in the THF-containing waste gas and form GBL adsorption liquid containing THF.
[0052] (2) Then, the GBL adsorption liquid containing THF flows to the feed preheater 3 from the absorption tower kettle outlet for preheating.
[0053] (3) Then, the preheated GBL adsorption liquid containing THF flows to the THF rectification tower 4 from the first rectification tower inlet of the middle of the two segments of packing of the THF rectification tower 4 for rectification.
[0054] (4) Then, the gas phase after rectification flows out from the first rectification tower outlet at the top of the THF rectification tower 4 to the gas phase condenser 5, and flows to the THF recovery tank 6 after condensation, and the condensation product is returned to the THF rectification tower 4 from the second rectification tower inlet of the upper part of the packing of the THF rectification tower 4 through the reflux pump 7, and is recovered at the THF recovery device.
[0055] (5) At the same time, the liquid phase after rectification flows to the feed preheater 3 from the second rectification tower outlet at the bottom of the THF rectification tower 4, and exchanges heat with the GBL adsorption liquid containing THF in the feed preheater 3;
[0056] (6) Then, the liquid phase after heat exchange flows to the cooler 2 for cooling, and returns to the THF absorption tower 1 from the GBL adsorbent reuse inlet of the upper part of the packing of the THF absorption tower 1, and continues to be reused as an adsorbent.
[0057] The above description of the embodiments is to facilitate the ordinary skilled in the art to understand and use the utility model. The person skilled in the art can obviously easily make various modifications to these embodiments, and the general principles described herein are applied to other embodiments without the need for creative labor. Therefore, the utility model is not limited to the above embodiments, and the improvements and modifications made by the person skilled in the art according to the disclosure of the utility model without departing from the scope of the utility model should be within the protection scope of the utility model.
Claims
1. A device for absorbing THF-containing waste gas using GBL, characterized by, The system comprises a THF absorption tower (1), a feed preheater (3), a THF rectifying tower (4), and a gas phase condenser (5), wherein, The THF absorption tower (1) is provided with a GBL adsorbent inlet at the upper part of the filler, a THF-containing waste gas inlet at the lower part of the filler, and an absorption tower kettle outlet at the bottom, and the absorption tower kettle outlet is connected to the first heat exchange inlet of the feed preheater (3), The THF rectifying tower (4) comprises segmented fillers arranged in the vertical direction, a first THF rectifying tower inlet arranged between the segmented fillers, a second THF rectifying tower inlet arranged at the upper part of the segmented fillers, and a first THF rectifying tower outlet arranged at the top, wherein the first THF rectifying tower inlet is connected to the first heat exchange outlet of the feed preheater (3), the first THF rectifying tower outlet is connected to the gas phase condenser (5), and the outlet of the gas phase condenser (5) is connected to the second THF rectifying tower inlet and a THF recovery point, respectively.
2. The device for absorbing THF-containing waste gas by GBL according to claim 1, characterized in that, The bottom of the THF rectifying tower (4) is provided with a second THF rectifying tower outlet, which is connected to the second heat exchange inlet of the feed preheater (3), so that the liquid phase flowing from the THF rectifying tower (4) to the feed preheater (3) can exchange heat with the GBL adsorbent for absorbing THF.
3. The device for absorbing THF-containing waste gas by GBL according to claim 1, characterized in that, The second heat exchange outlet of the feed preheater (3) is also connected to a cooler (2), and the cooler (2) is connected to the THF absorption tower (1).
4. The device for absorbing THF-containing waste gas by GBL according to claim 3, characterized in that, The THF absorption tower (1) is also provided with a GBL adsorbent recycling inlet at the upper part of the filler, which is connected to the cooler (2).
5. The device for absorbing THF-containing waste gas by GBL according to claim 3, characterized in that, The absorption tower kettle outlet is in communication with the channel from the second heat exchange outlet of the feed preheater (3) to the cooler (2).
6. The device for absorbing THF-containing waste gas by GBL according to claim 2, characterized in that, The absorption tower kettle outlet is provided with an absorption tower kettle pump (8), and the second THF rectifying tower outlet is provided with a rectifying tower kettle pump (9).
7. The device for absorbing THF-containing waste gas by GBL according to claim 1, characterized in that, The outlet of the gas phase condenser (5) is provided with a reflux pump (7) to return the gas phase condensation product to the THF rectifying tower (4) and the THF recovery point through the reflux pump (7), respectively.
8. The device for absorbing THF-containing waste gas by GBL according to claim 7, characterized in that, A THF recovery tank (6) is also arranged between the gas phase condenser (5) and the reflux pump (7).
9. The device for absorbing THF-containing waste gas by GBL according to claim 1, characterized in that, The THF rectifying tower (4) is provided with two segments of fillers with the same height.
10. The device for absorbing THF-containing waste gas by GBL according to claim 1, characterized in that, The THF rectifying tower (4) is a vacuum rectifying tower provided with a siphon-type reboiler.