Treatment device for ethylene oxide-containing organic waste gas

Abstract

The utility model provides a treatment device for ethylene oxide-containing organic waste gas. The treatment device comprises a condenser, a washing tower, a buffer tank, an RTO furnace and a desorption tower, the condenser is provided with a waste gas input pipeline and a condensed gas output pipeline; the washing tower is provided with a to-be-washed gas inlet, a washed gas outlet, a water inlet and a washing liquid outlet, and the to-be-washed gas inlet is communicated with a condensed gas output pipeline of the condenser; the buffer tank is provided with a to-be-buffered gas inlet and a buffered gas outlet, and the to-be-buffered gas inlet is communicated with the washed gas outlet of the washing tower; the RTO furnace is provided with a to-be-burnt gas inlet and a gas output port; the desorption tower is provided with a to-be-desorbed liquid inlet, a desorption liquid outlet, a nitrogen inlet and a desorbed gas outlet, and the to-be-desorbed liquid inlet is communicated with the washing liquid outlet of the washing tower. The treatment device disclosed by the utility model can be used for safely and effectively treating the ethylene oxide-containing organic waste gas without secondary pollution, and also can be used for safely and stably treating the waste gas with fluctuating amount and composition.

Description

Technical Field

[0001] The utility model relates to the technical field of waste gas treatment, in particular to a treatment device for organic waste gas containing ethylene oxide. Background Art

[0002] The ethoxylation reaction is carried out in the ethoxylation device, so the ethoxylation device can be used to produce polyether and other products. In each link of the production, waste gas containing organic gases such as ethylene oxide, hydrogen, and isopentenol will be generated. These waste gases are usually destroyed to convert these volatile organic compounds (VOCs) into harmless substances. Since ethylene oxide is a toxic and explosive substance, the requirements for the treatment process of organic waste gas containing ethylene oxide are relatively high.

[0003] Currently, the existing technology is unable to achieve safe and effective treatment of organic waste gas containing ethylene oxide, and is unable to solve problems such as fluctuations in waste gas volume and composition, and secondary pollution during the treatment process. How to solve the above problems is a technical problem that needs to be solved urgently. Utility Model Content

[0004] In view of the above problems, the utility model provides a treatment device for organic waste gas containing ethylene oxide.

[0005] The utility model provides a treatment device for organic waste gas containing ethylene oxide, comprising:

[0006] Condenser,

[0007] Scrubber,

[0008] Buffer tank,

[0009] RTO furnace, and

[0010] Desorption tower;

[0011] Wherein, the condenser is provided with an exhaust gas input pipeline and a condensed gas output pipeline; the washing tower is provided with a gas inlet to be washed, a gas outlet after washing, a water inlet and a washing liquid outlet, and the gas inlet to be washed is connected with the condensed gas output pipeline of the condenser; the buffer tank is provided with a gas inlet to be buffered and a gas outlet after buffering, and the gas inlet to be buffered is connected with the gas outlet after washing of the washing tower; the RTO furnace is provided with a gas inlet to be burned and a gas output port, and the gas inlet to be burned is connected with the gas outlet after buffering of the buffer tank; the desorption tower is provided with a liquid inlet to be desorbed, a desorption liquid outlet, a nitrogen inlet and a desorption gas outlet, and the liquid inlet to be desorbed is connected with the washing liquid outlet of the washing tower.

[0012] Optionally, the water inlet of the washing tower is a desalted water inlet.

[0013] Optionally, the condenser is further provided with a purge gas input pipeline and a purge gas output pipeline.

[0014] Optionally, a condensing water pipe is provided in the condenser, and a water inlet of the condensing water pipe is connected to a water outlet of the condensing water pipe.

[0015] Optionally, a connected absorption layer and a gas uniform distribution layer are provided in the buffer tank, the gas inlet of the absorption layer is connected to the gas inlet to be buffered, the gas outlet of the absorption layer is connected to the gas inlet of the gas uniform distribution layer, and the gas outlet of the gas uniform distribution layer is connected to the gas outlet after buffering.

[0016] Optionally, the buffer tank is also provided with a monitoring device for monitoring the exhaust gas concentration in the gas flowing out of the gas outlet after buffering.

[0017] Optionally, the buffer tank is arranged between the washing tower and the RTO furnace.

[0018] Optionally, the buffer tank is also provided with a second exhaust gas input pipeline.

[0019] Optionally, the RTO furnace is further provided with an organic matter concentration monitoring device for monitoring the organic matter concentration in the gas output through the gas output port.

[0020] Optionally, the desorption liquid outlet of the desorption tower is connected to the water inlet of the washing tower.

[0021] Beneficial effects:

[0022] The treatment device of the utility model first condenses the waste gas through a condenser, and then the water in the washing tower absorbs ethylene oxide. The waste gas is then deliquated and evenly buffered in a buffer tank and then enters the RTO furnace for oxidative combustion. The washing liquid after absorbing ethylene oxide in the washing tower enters the analysis tower and is analyzed by nitrogen. The treatment device can safely and effectively treat organic waste gas containing ethylene oxide without secondary pollution, and can also safely and stably treat waste gas with fluctuating waste gas volume and composition. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of a specific implementation of a device for treating organic waste gas containing ethylene oxide provided by the utility model;

[0024] Description of Reference Numerals

[0025] 1 condenser 2 washing tower 3 buffer tank

[0026] 4RTO furnace 5 desorption tower

[0027] 11 Exhaust gas input pipeline 12 Condensed gas output pipeline 13 Purge gas input pipeline

[0028] 14 Purge gas output pipeline

[0029] 21 Gas inlet to be cleaned 22 Gas outlet after cleaning 23 Cleaning liquid outlet

[0030] 31 Gas inlet to be buffered 32 Gas outlet after buffering 33 Absorption layer

[0031] 34 Gas uniform distribution layer 35 Second exhaust gas input pipeline

[0032] 41 Inlet for gas to be burned 42 Gas outlet

[0033] 51 inlet of desorbed liquid 52 outlet of desorbed liquid 53 inlet of nitrogen

[0034] 54 Desorption gas outlet DETAILED DESCRIPTION

[0035] The present application is further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present application will become clearer and more specific.

[0036] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0037] In this utility model, the term "VOCs" means volatile organic compounds;

[0038] In the present invention, the term "RTO furnace" means a regenerative thermal oxidation furnace.

[0039] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0040] The utility model provides a treatment device for organic waste gas containing ethylene oxide, such as Figure 1 As shown, including:

[0041] Condenser 1,

[0042] Washing tower 2,

[0043] Buffer tank 3,

[0044] RTO furnace 4, and

[0045] Desorption tower 5;

[0046] Among them, the condenser 1 is provided with a waste gas input pipeline 11 and a condensed gas output pipeline 12; the washing tower 2 is provided with a gas inlet 21 to be washed, a gas outlet 22 after washing, a water inlet and a washing liquid outlet 23, and the gas inlet 21 to be washed is connected to the condensed gas output pipeline 12 of the condenser 1; the buffer tank 3 is provided with a gas inlet 31 to be buffered and a gas outlet 32 ​​after buffering, and the gas inlet 31 to be buffered is connected to the gas outlet 22 after washing of the washing tower 2; the RTO furnace 4 is provided with a gas inlet 41 to be burned and a gas outlet 42, and the gas inlet 41 to be burned is connected to the gas outlet 32 ​​after buffering of the buffer tank 3; the desorption tower 5 is provided with a liquid inlet 51 to be desorbed, a desorption liquid outlet 52, a nitrogen inlet 53 and a desorption gas outlet 54, and the liquid inlet 51 to be desorbed is connected to the washing liquid outlet 23 of the washing tower 2.

[0047] Furthermore, the exhaust gas input pipeline 11 and the condensed gas output pipeline 12 may be provided with flow rate control valves respectively to control the gas flow rate in the pipelines in real time.

[0048] The above-mentioned treatment device of the utility model can be used for treating the waste gas containing ethylene oxide generated by the ethoxylation device, etc. The waste gas generated by the ethoxylation device often contains ethylene oxide, polyether, hydrogen, isopentanol and other gases. According to the flow direction of the waste gas, the waste gas enters the condenser, the washing tower, the buffer tank and the RTO furnace in sequence, and the washing tower and the desorption tower are used in combination to treat the washing liquid after absorbing ethylene oxide. The exhaust gas from the ethoxylation device can directly enter the condenser 1 through the exhaust gas input pipeline 11 for condensation, and the condensed gas flows through the condensed gas output pipeline 12 and the gas inlet 21 to be washed and then enters the washing tower 2; ethylene oxide is easily soluble in water, and part of the ethylene oxide in the condensed gas entering the washing tower 2 can be absorbed by the water in the washing tower 2 to obtain a washed gas with a reduced ethylene oxide concentration, while part of the ethylene oxide "stays" in the washing liquid; the gas after washing and removing ethylene oxide flows through the washed gas outlet 22 and the gas inlet 31 to be buffered into the buffer tank 3 for buffering, and the buffered gas that is buffered and mixed more evenly flows through the buffered gas outlet 32 ​​and the gas inlet 41 to be burned and enters the RTO furnace 4 for incineration treatment, and the hydrogen and the like contained in the buffered gas can be more safely burned into carbon dioxide and water, etc., and the safe gas obtained after combustion can be output through the gas output port 42. The water that absorbs ethylene oxide in the washing tower 2 becomes washing liquid and can flow through the washing liquid outlet 23 and the desorbed liquid inlet 51 in sequence into the desorption tower 5. The nitrogen decomposes the ethylene oxide in the washing liquid and flows out through the desorption gas outlet 54.

[0049] In the above-mentioned treatment device, nitrogen is introduced into the desorption tower 5 through the nitrogen inlet 53, and the saturated vapor pressure of the water-ethylene oxide binary mixed system is controlled by nitrogen to desorb ethylene oxide in the solution (liquid to be desorbed), thereby changing the traditional ethylene oxide treatment process to desorb the ethylene oxide aqueous solution by heating. The utility model uses a desorption tower to desorb the washing liquid containing ethylene oxide, which is safer and more energy-saving. The nitrogen and ethylene oxide mixed gas output through the desorption gas outlet 54 can be separated, and the separated ethylene oxide can enter the ethylene oxide storage container to collect the ethylene oxide and recycle it.

[0050] It can be seen that the above-mentioned treatment device of the utility model can safely and effectively treat the organic waste gas containing ethylene oxide, and the treatment process will not generate secondary pollution. In addition, part of the washing liquid that absorbs ethylene oxide flowing out through the washing liquid outlet 23 can enter the desorption tower 5 for desorption, and the other part can enter the washing tower 2 through the water inlet for recycling.

[0051] In one embodiment of the above-mentioned treatment device of the present invention, the water inlet of the washing tower 2 is a desalted water inlet.

[0052] In this preferred embodiment, the scrubber uses desalted water to absorb ethylene oxide in the waste gas. Based on the characteristics that water and ethylene oxide can be miscible in any proportion, the original alkali solution is replaced with desalted water for absorption, and the high concentration of ethylene oxide in the waste gas can be partially absorbed by the scrubber during discharge, thereby reducing the organic matter concentration of the RTO furnace intake. When the gas outlet 42 of the RTO furnace stops exhausting exhaust gas, the dilution gas nitrogen continuously passing through the desorption tower 5 desorbs the ethylene oxide absorbed in the desalted water to ensure the stability of the exhaust gas intake at the front end of the RTO furnace.

[0053] In one embodiment of the processing device of the utility model, Figure 1 As shown, the condenser 1 is further provided with a purge gas input pipeline 13 and a purge gas output pipeline 14 .

[0054] Furthermore, the purge gas input pipeline 13 and the purge gas output pipeline 14 may be provided with flow rate control valves respectively to control the flow rates of the gas flowing through the pipelines respectively.

[0055] It should be noted that when the above-mentioned treatment device stops running, a high-temperature purge gas such as 200-250°C can be introduced into the condenser 1 through the purge gas input pipeline 13. The purge gas can be vaporized at high temperature to remove the polyether condensed in the condenser 1 by condensation. The polyether leaves the condenser 1 along with the purge gas through the purge gas output pipeline 14 to avoid the condensed polyether from sticking and clogging the condenser 1. The purge gas can be a conventional gas in the art such as nitrogen, and the above-mentioned treatment device can also be provided with a purge gas heating device to heat the purge gas introduced into the condenser 1.

[0056] In addition, the condenser 1 may have a gas inlet, and the waste gas input pipeline 11 and the purge gas input pipeline 13 are respectively connected to the gas inlet, or the condenser 1 may have two gas inlets respectively connected to the waste gas input pipeline 11 and the purge gas input pipeline 13. The condenser 1 may have a gas outlet, and the condensed gas output pipeline 12 and the purge gas output pipeline 14 are respectively connected to the gas outlet, or the condenser 1 may have two gas outlets respectively connected to the condensed gas output pipeline 12 and the purge gas output pipeline 14.

[0057] In one embodiment of the above-mentioned processing device of the utility model, a condensation water pipe is provided in the condenser 1, and the water inlet of the condensation water pipe is connected with the water outlet of the condensation water pipe.

[0058] It should be noted that there can be one or more condensing water pipes, one condensing water pipe can be an annular coil, and multiple condensing water pipes can be arranged vertically at intervals, and the utility model is not limited thereto. The water inlet of the condensing water pipe is connected to the water outlet of the condensing water pipe, so that the condenser adopts a circulating water cooling method, which can condense and collect polyethers and the like in the exhaust gas, reduce the concentration of volatile organic matter in the exhaust gas, and reduce the exhaust gas temperature of the workshop exhaust gas (exhaust).

[0059] In one embodiment of the processing device of the utility model, Figure 1 As shown, the buffer tank 3 is provided with a connected absorption layer 33 and a gas uniform distribution layer 34, the gas inlet of the absorption layer 33 is connected to the gas inlet 31 to be buffered, the gas outlet of the absorption layer 33 is connected to the gas inlet of the gas uniform distribution layer 34, and the gas outlet of the gas uniform distribution layer 34 is connected to the post-buffering gas outlet 32.

[0060] It should be noted that a buffer tank 3 is provided in front of the RTO furnace 4. The buffer tank 3 can be arranged near one end of the scrubbing tower 2. The buffer tank is mainly used to reduce the impact of the instantaneous exhaust gas from the workshop on the exhaust gas of the RTO furnace and to collect the waste liquid entrained in the exhaust gas. As above, an absorption layer and a gas uniform distribution layer are provided in the buffer tank. The absorption layer can be an activated carbon layer, a molecular sieve layer, and a combined material layer to absorb liquid moisture in the exhaust gas; the gas uniform distribution layer 34 can be provided with an airflow baffle, an airflow buffer plate, or a gas distribution plate, etc. The gas uniform distribution layer mixes gases of different components evenly to avoid gas phase stratification. The gas after dehydration and uniform mixing enters the RTO furnace for incineration, which greatly improves the stability and safety of the RTO furnace.

[0061] In one embodiment of the above-mentioned treatment device of the present invention, the buffer tank 3 is also provided with a monitoring device for monitoring the exhaust gas concentration in the gas flowing out of the gas outlet 32 ​​after buffering.

[0062] It should be noted that the monitoring device for monitoring the exhaust gas concentration in the gas flowing out of the buffered gas outlet 32 ​​may be an exhaust gas concentration monitor, which may be provided at the buffered gas outlet 32, may be located inside or outside the buffer tank 3, or may be provided between the buffered gas outlet 32 ​​and the inlet 41 of the gas to be burned. By providing the monitoring device, it is ensured that the exhaust gas concentration entering the heat storage combustion device such as the RTO furnace is lower than 25% of the lower limit of the explosion limit, thereby effectively improving safety.

[0063] In one embodiment of the processing device of the utility model, Figure 1 As shown, the buffer tank 3 is arranged between the washing tower 2 and the RTO furnace 4.

[0064] By arranging a buffer tank 3 between the scrubbing tower 2 and the RTO furnace 4, the scrubbed gas flowing out of the scrubbing tower 2 can directly and quickly enter the buffer tank 3 for deliquescence and buffering, and then enter the RTO furnace 4 for combustion, thereby saving paths and improving the processing rate.

[0065] In one embodiment of the processing device of the utility model, Figure 1 As shown, the buffer tank 3 is further provided with a second exhaust gas input pipeline 35 .

[0066] Furthermore, a flow rate control valve may be provided on the second exhaust gas input pipeline 35 to perform real-time control on the flow rate of the gas flowing through the pipeline.

[0067] As described above, by setting up a monitoring device to monitor the exhaust gas concentration in the gas to be burned entering the RTO furnace, when the monitored exhaust gas concentration is lower than 25% of the lower limit of the explosion limit, the exhaust gas components are all within the design range and operate normally at this time, and other exhaust gases do not need to be added to the buffer tank. On the contrary, when the monitored exhaust gas concentration is greater than or equal to 25% of the lower limit of the explosion limit, the content of combustible components in the exhaust gas is high. At this time, according to the monitoring results of the monitoring device, other exhaust gases (exhaust gases with low combustible component content) can be quantitatively added through the second exhaust gas input pipeline 35 to make the exhaust gas concentration in the gas to be burned entering the RTO furnace lower than 25%. Therefore, the treatment device of the utility model can safely treat the organic waste gas containing ethylene oxide with fluctuating components. When the amount of waste gas to be treated is too low, other exhaust gases can also be quantitatively added through the second exhaust gas input pipeline 35 to make the treatment device operate more stably. Therefore, the treatment device of the utility model can also stably treat the waste gas with fluctuating exhaust gas amount.

[0068] In one embodiment of the above-mentioned processing device of the present invention, the RTO furnace 4 is further provided with an organic matter concentration monitoring device for monitoring the organic matter concentration in the gas output through the gas output port 42 .

[0069] It should be noted that the RTO furnace realizes catalytic combustion of the exhaust gas to remove organic gas in the exhaust gas; the organic matter concentration monitoring device can be set at the gas outlet 42, and the organic matter concentration in the gas output through the gas outlet 42 is monitored in real time by the organic matter concentration monitoring device, so that the VOCs concentration in the exhaust gas from the gas outlet 42 is ≤60mg / Nm 3 .

[0070] In one embodiment of the above-mentioned treatment device of the present invention, the desorption liquid outlet 52 of the desorption tower 5 is communicated with the water inlet of the washing tower 2 .

[0071] After nitrogen desorption, a desorption liquid such as water substantially free of ethylene oxide is obtained, which flows out through the desorption liquid outlet 52 and can enter the washing tower through the water inlet for recycling.

[0072] In the description of the present application, it should be noted that the terms "upper", "lower", "inside", "outside", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships in the working state of the present application. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on the present application.

[0073] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect" and "connect" should be understood in a broad sense. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0074] The present application has been described above in conjunction with preferred embodiments, but these embodiments are only exemplary and serve only as an illustration. On this basis, various replacements and improvements may be made to the present application, all of which fall within the scope of protection of the present application.

Claims

1. A device for treating organic waste gas containing ethylene oxide, characterized in that: include: Condenser (1), Scrubber (2), Buffer tank (3), RTO furnace (4), and Desorption tower (5); The condenser (1) is provided with an exhaust gas input pipeline (11) and a condensed gas output pipeline (12); the scrubbing tower (2) is provided with a to-be-scrubbed gas inlet (21), a post-scrubbed gas outlet (22), a water inlet and a scrubbing liquid outlet (23), the to-be-scrubbed gas inlet (21) being connected to the condensed gas output pipeline (12) of the condenser (1); the buffer tank (3) is provided with a to-be-scrubbed gas inlet (31) and a post-scrubbed gas outlet (32), the to-be-scrubbed gas inlet (31) being connected to the The RTO furnace (4) is provided with a to-be-combusted gas inlet (41) and a gas outlet (42), and the to-be-combusted gas inlet (41) is communicated with the to-be-buffered gas outlet (32) of the buffer tank (3); the desorption tower (5) is provided with a to-be-desorbed liquid inlet (51), a desorption liquid outlet (52), a nitrogen inlet (53) and a desorption gas outlet (54), and the to-be-desorbed liquid inlet (51) is communicated with the washing liquid outlet (23) of the scrubbing tower (2).

2. The processing device according to claim 1, characterized in that The water inlet of the washing tower (2) is a desalted water inlet.

3. The processing device according to claim 1, characterized in that The condenser (1) is also provided with a purge gas input pipeline (13) and a purge gas output pipeline (14).

4. The processing device according to any one of claims 1 to 3, characterized in that: The condenser (1) is provided with a condensation water pipe, and a water inlet of the condensation water pipe is connected to a water outlet of the condensation water pipe.

5. The processing device according to claim 1, characterized in that The buffer tank (3) is provided with an absorption layer (33) and a gas uniform distribution layer (34) which are connected to each other; the gas inlet of the absorption layer (33) is connected to the gas inlet (31) to be buffered; the gas outlet of the absorption layer (33) is connected to the gas inlet of the gas uniform distribution layer (34); and the gas outlet of the gas uniform distribution layer (34) is connected to the post-buffering gas outlet (32).

6. The processing device according to claim 1 or 5, characterized in that: The buffer tank (3) is also provided with a monitoring device for monitoring the exhaust gas concentration in the gas flowing out through the buffered gas outlet (32).

7. The processing device according to claim 1 or 5, characterized in that: The buffer tank (3) is arranged between the washing tower (2) and the RTO furnace (4).

8. The processing device according to claim 1 or 5, characterized in that: The buffer tank (3) is also provided with a second exhaust gas input pipeline (35).

9. The processing device according to claim 1, characterized in that The RTO furnace (4) is also provided with an organic matter concentration monitoring device for monitoring the organic matter concentration in the gas output through the gas output port (42).

10. The processing device according to claim 1, characterized in that The desorption liquid outlet (52) of the desorption tower (5) is communicated with the water inlet of the washing tower (2).

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