Dichloromethane adsorption and collection device

Abstract

The utility model relates to the technical field of gas collecting devices, in particular to a dichloromethane adsorbing and collecting device which comprises a heating kettle, a reaction container, a waste liquid collecting bottle, a low-temperature cooling circulating pump, a cold trap and a vacuum bottle, the heating pot is used for heating a reaction container containing a mixture; the reaction container is connected with a gas inlet of the waste liquid collecting bottle; a gas outlet of the waste liquid collecting bottle is connected with a gas inlet of the cold trap; the cold trap is arranged in a thermos bottle filled with dry ice; the low-temperature cooling circulating pump is connected with the waste liquid collecting bottle and is used for cooling the waste liquid collecting bottle. Heating the mixture through a heating pot to generate dichloromethane gas, and then carrying out primary liquefaction and collection on the dichloromethane gas in a waste liquid collection bottle; carrying out secondary liquefaction on the dichloromethane gas in the cold trap and collecting the dichloromethane gas; in the secondary liquefaction process, the cooling temperature of the dry ice is lower than the liquefaction temperature of the dichloromethane, and the liquefaction effect on the dichloromethane is better.

Description

Technical Field

[0001] The utility model relates to the technical field of gas collection devices, in particular to a dichloromethane adsorption collection device. Background Art

[0002] Dichloromethane is an organic compound, a colorless, transparent liquid with a pungent odor similar to ether. It is slightly soluble in water, soluble in ethanol and ether. Under normal conditions of use, it is a non-flammable, low-boiling-point solvent. Its vapor will only produce a weakly burning mixed gas when it reaches a high concentration in high-temperature air[4]. It is often used to replace flammable petroleum ether, ether, etc. On October 27, 2017, the World Health Organization's International Agency for Research on Cancer published a preliminary summary of the list of carcinogens for reference. Dichloromethane is included in the list of Class 2A carcinogens. On January 23, 2019, dichloromethane was included in the List of Toxic and Hazardous Air Pollutants (2018). On July 23, 2019, dichloromethane was included in the List of Toxic and Hazardous Water Pollutants (First Batch).

[0003] The four common organic solvents used in CRO chemical research and development include petroleum ether, ethyl acetate, dichloromethane and ethanol. In research and development experiments, based on cost and process considerations, dichloromethane is an essential and commonly used raw and auxiliary material. The sewage treatment process used to treat the five conventional items of sewage (PH, ammonia nitrogen, phosphorus content, solids, COD, BOD) cannot effectively remove the dichloromethane content in the sewage, and the sewage discharge cannot meet the standards.

[0004] In the prior art, the process of collecting dichloromethane in a reaction mixture containing dichloromethane generally involves evaporating the reaction mixture through a heating pot; the gas generated after evaporation is cooled through a hydrazine condenser connected to a low-temperature cooling circulation pump and then becomes liquid and is collected in a round-bottom bottle; however, since the liquefaction temperature of dichloromethane is -40°C, part of the dichloromethane vapor is difficult to be effectively liquefied under the cooling level of the original device, and will be discharged into the external environment with the air or re-enter the water and enter the external environment with the flow of water, causing environmental pollution. Utility Model Content

[0005] In view of the problems existing in the prior art, the purpose of the utility model is to provide a dichloromethane adsorption and collection device to solve the problems in the prior art that when dichloromethane is processed, the existing devices are difficult to effectively liquefy dichloromethane and dichloromethane is easy to pollute the environment.

[0006] A dichloromethane collecting device comprises a heating pot, a reaction container, a waste liquid collecting bottle, a low temperature cooling circulation pump, a cold trap and a thermos bottle;

[0007] The heating pot is used to heat the reaction container containing the mixture; the reaction container is connected to the air inlet of the waste liquid collection bottle; the air outlet of the waste liquid collection bottle is connected to the air inlet of the cold trap; the cold trap is installed in a thermos containing dry ice; the low-temperature cooling circulation pump is connected to the waste liquid collection bottle for cooling the waste liquid collection bottle.

[0008] Preferably, it also includes a circulating vacuum water pump and a water tank; the air outlet of the cold trap is connected to the air inlet of the circulating vacuum water pump; and the water outlet of the circulating vacuum water pump is connected to the water tank.

[0009] Preferably, a bracket is provided on one side of the heating pot, and the bracket is connected to the waste liquid collection bottle via a binding belt.

[0010] Preferably, the heating pot is a water bath heating pot.

[0011] Preferably, a cooling liquid channel is provided in the waste liquid collection bottle; and the low-temperature cooling circulation pump is connected to the cooling liquid channel.

[0012] Preferably, a suction filtration pressure relief port is provided on the top of the waste liquid collection bottle.

[0013] Preferably, a round-bottom bottle is provided at the bottom of the waste liquid collection bottle, and the round-bottom bottle is detachable.

[0014] Preferably, a heat-insulating layer for keeping the dry ice warm is provided in the cold trap.

[0015] Beneficial effects: In the utility model, the mixture is heated by a heating pot to generate dichloromethane gas, and then the pollutants generated by the gasification of the mixture are liquefied in a waste liquid collection bottle, and the dichloromethane gas is liquefied and collected once; the dichloromethane gas is liquefied and collected for a second time in a cold trap; during the secondary liquefaction process, the cooling temperature of the dry ice is lower than the liquefaction temperature of the dichloromethane, and the liquefaction effect of the dichloromethane is good; the dry ice is used as a consumable material, the cost is low, the liquefaction effect is good, it is beneficial to the recovery of dichloromethane, and the environment is better protected. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the specification will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0017] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the utility model.

[0018] In the figure: 1. water bath heating pot; 101. bracket; 2. reaction container; 3. binding belt; 4. waste liquid collection bottle; 401. suction filtration pressure relief port; 5. low-temperature cooling circulation pump; 6. cold trap; 7. thermos flask; 8. dry ice; 9. circulating vacuum water pump; 10. water tank. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention are described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. For ease of explanation, the terms "vertical", "horizontal", "left", "right", "upper", "lower", "inner", "outer", "bottom", etc. used in this specification indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application.

[0020] It should be noted that the embodiments of the present invention and the features involved in the embodiments can be combined with each other without conflict. 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.

[0021] like Figure 1 The dichloromethane adsorption and collection device shown comprises a water bath heating pot 1, a reaction container 2, a waste liquid collection bottle 4, a low temperature cooling circulation pump 5, a cold trap 6, a thermos bottle 7, a circulating vacuum water pump 9 and a water tank 10;

[0022] A bracket 101 is provided on one side of the water bath heating pot 1; a vertically arranged waste liquid collection bottle 4 is connected to one side of the bracket 101 through a binding belt 3; the reaction container 2 is arranged obliquely upward, and the bottom part for holding the mixture is inserted into the pot body of the water bath heating pot 1, and the top of the reaction container 2 is connected to the air inlet of the waste liquid collection bottle 4; a coolant channel is provided on the inner side of the top of the waste liquid collection bottle 4, and the coolant channel is connected to the low-temperature cooling circulation pump 5 through a first hose, and the low-temperature cooling circulation pump 5 is provided with a coolant, and the coolant is used to cool the waste liquid The collecting bottle 4 is cooled; a second hose is connected to the air outlet on one side of the top of the waste liquid collecting bottle 4, the second hose is connected to the air inlet pipe on the top of the cold trap 6, and the bottom end of the air inlet pipe extends downward to near the bottom of the cold trap 6; the cold trap 6 is inserted into a thermos 7 pre-set with dry ice 8; a third hose is connected to the air outlet of the circulating vacuum water pump 9, one end of the third hose is connected to the air outlet pipe set at the top of one side of the cold trap 6; a fourth hose is connected to the water outlet of the circulating vacuum water pump 9, one end of the fourth hose is connected to the water tank 10. The water bath heating pot 1 is a heating pot in the prior art. The circulating vacuum water pump 9 is a prior art, and is provided with an air inlet, an air outlet, a water inlet and a water outlet.

[0023] In this embodiment, a mixture containing dichloromethane is loaded into the reaction vessel 2; the water bath heating pot 1 is used to heat the reaction vessel 2, and the mixture in the reaction vessel 2 is evaporated by heat to produce steam mixed with dichloromethane gas; the dichloromethane gas enters the waste liquid collection bottle 4; under the action of the low-temperature cooling circulation pump 5, the first hose and the coolant circulating in the coolant channel, part of the dichloromethane gas is liquefied and collected in the round-bottomed bottle at the bottom of the waste liquid collection bottle 4; the remaining unliquefied dichloromethane gas enters the cold trap 6 through the second hose, and is liquefied at the bottom of the cold trap 6 under the cooling action of dry ice 8; the remaining dichloromethane and the remaining gas enter the circulating vacuum water pump 9 through the third hose, enter the water, and are then transported to the water tank 10 for collection, and are treated by sewage treatment facilities. The dichloromethane gas stays in the cold trap 6 for a long time, which is conducive to the liquefaction of dichloromethane.

[0024] The round bottom bottle arranged at the bottom of the waste liquid collecting bottle 4 is detachably connected.

[0025] In this embodiment, the round bottom bottle is detachably connected and takes necessary sealing means to prevent leakage of dichloromethane; specific sealing means such as sealing gaskets are prior art and will not be described in detail here. A suction filtration pressure relief port 401 is provided on one side of the top of the waste liquid collection bottle 4. The suction filtration pressure relief port 401 is used to prevent the air pressure in the waste liquid collection bottle 4 from being too high and maintain the normal use of the device.

[0026] The inner diameter of the mouth of the thermos bottle 7 is matched with the outer diameter of the lower part of the cold trap 6 , and a heat-insulating layer is arranged inside the thermos bottle 7 .

[0027] In this embodiment, the mouth of the thermos bottle is adapted to the outer diameter of the lower part of the cold trap 6, which can facilitate the insertion of the cold trap 6 while sealing the mouth of the thermos bottle 7, so that the insulation effect of the thermos bottle is better; the insulation layer is mainly made of cotton, and the cotton is laid on the dry ice 8 set in the bottle. The dry ice 8 is laid around the cold trap 6. The dry ice 8 has a better cooling effect on the cold trap 6, and at the same time can extend the time required for the sublimation of the dry ice 8, thereby reducing the consumption of dry ice.

[0028] Working principle: The water bath heating pot 1 is used to heat the mixture in the reaction container 2, and the mixture evaporates into gas due to the heat, and the gas enters the waste liquid collection bottle 4; the low-temperature cooling circulation pump 5 cools the waste liquid collection bottle 4, and the dichloromethane gas is liquefied when it is cooled, and the liquefied dichloromethane is collected in the round-bottom bottle of the waste liquid collection bottle 4; the remaining dichloromethane gas enters the cold trap 6, is liquefied when it is cooled, and is collected at the bottom of the cold trap 6; the remaining dichloromethane gas enters the circulating vacuum water pump 9, is absorbed by the water flowing through the circulating vacuum water pump 9 and is transported to the water tank 10.

[0029] The device in this embodiment liquefies the methylene chloride that becomes gaseous after being heated twice; the liquefaction temperature of methylene chloride is -40°C; the primary liquefaction temperature in this embodiment is relatively high, and the cooling temperature of the coolant of the low-temperature cooling circulation pump 5 in the prior art is about minus 18°C, which has a low removal effect on the methylene chloride gas generated in the mixture, and the secondary liquefaction temperature is relatively low. The cooling temperature of the dry ice 8 can reach minus 78.5°C, which has a relatively good liquefaction effect on methylene chloride and can effectively liquefy methylene chloride. The thermos flask 7 required in the secondary liquefaction process can be the thermos flask 7 in the prior art, and the price of the thermos flask 7 is relatively low. The price of the dry ice 8 is relatively low. In actual use, the secondary liquefaction process is added, the removal degree of methylene chloride is significantly improved, the cost consumed is relatively low, and the methylene chloride can be effectively liquefied and recovered, protecting the environment, and suitable for promotion and use.

[0030] Although preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A dichloromethane adsorption collection device, characterized in that: It includes a heating pot, a reaction container, a waste liquid collection bottle, a low-temperature cooling circulation pump, a cold trap and a thermos bottle; The heating pot is used to heat the reaction container containing the mixture; the reaction container is connected to the air inlet of the waste liquid collection bottle; the air outlet of the waste liquid collection bottle is connected to the air inlet of the cold trap; the cold trap is installed in a thermos bottle containing dry ice; the low-temperature cooling circulation pump is connected to the waste liquid collection bottle for cooling the waste liquid collection bottle.

2. A dichloromethane adsorption collection device according to claim 1, characterized in that: It also includes a circulating vacuum water pump and a water tank; the air outlet of the cold trap is connected to the air inlet of the circulating vacuum water pump; and the water outlet of the circulating vacuum water pump is connected to the water tank.

3. A dichloromethane adsorption collection device according to claim 2, characterized in that: A bracket is provided on one side of the heating pot, and the bracket is connected to the waste liquid collection bottle through a binding belt.

4. A dichloromethane adsorption collection device according to any one of claims 1 to 3, characterized in that: The heating pot is a water bath heating pot.

5. A dichloromethane adsorption collection device according to claim 4, characterized in that: A cooling liquid channel is arranged in the waste liquid collection bottle; and the low-temperature cooling circulation pump is connected to the cooling liquid channel.

6. A dichloromethane adsorption collection device according to claim 5, characterized in that: The top of the waste liquid collection bottle is provided with a suction filtration pressure relief port.

7. A dichloromethane adsorption collection device according to claim 5, characterized in that: A round bottom bottle is arranged at the bottom of the waste liquid collection bottle, and the round bottom bottle is detachable.

8. A dichloromethane adsorption collection device according to claim 1, characterized in that: The cold trap is provided with a heat-insulating layer for keeping the dry ice warm.

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