阅读说明：本技术 一种降低石蜡油中二氯甲烷含量的装置 (Device for reducing content of dichloromethane in paraffin oil ) 是由 邓斌 李�东 赵晓亮 孔德圣 金磊 于 2020-06-23 设计创作，主要内容包括：本发明公开了一种降低石蜡油中二氯甲烷含量的装置,涉及二氯甲烷分离工艺技术领域。本发明包括减压精馏塔,减压精馏塔一端通过管道连通有输送泵,减压精馏塔一端通过管道连通有换热器,换热器一端通过管道连通有第一真空泵,减压精馏塔一端通过管道连通有第一气压传感器,第一气压传感器一端通过管道与第一真空泵连通,减压精馏塔一端连通有氮气管,减压精馏塔一端通过氮气管连通有氮气发生装置,本发明通过氮气发生装置向减压精馏塔内部通入氮气,降低二氯甲烷在气相中的分压,同时加快上升气流流速,使石蜡油中二氯甲烷持续分离,有效降低了产出石蜡油中二氯甲烷含量,浓度低至100ppm以下,利于石蜡油的回收利用。(The invention discloses a device for reducing the content of dichloromethane in paraffin oil, and relates to the technical field of dichloromethane separation processes. The device comprises a reduced pressure rectifying tower, wherein one end of the reduced pressure rectifying tower is communicated with a delivery pump through a pipeline, one end of the reduced pressure rectifying tower is communicated with a heat exchanger through a pipeline, one end of the heat exchanger is communicated with a first vacuum pump through a pipeline, one end of the reduced pressure rectifying tower is communicated with a first gas pressure sensor through a pipeline, one end of the first gas pressure sensor is communicated with the first vacuum pump through a pipeline, one end of the reduced pressure rectifying tower is communicated with a nitrogen pipe, and one end of the reduced pressure rectifying tower is communicated with a nitrogen generating device through the nitrogen pipe.)

1. A device for reducing dichloromethane content in paraffin oil is characterized in that: comprises a decompression rectifying tower (1), one end of the decompression rectifying tower (1) is communicated with a delivery pump (2) through a pipeline, one end of the decompression rectifying tower (1) is communicated with a heat exchanger (3) through a pipeline, one end of the heat exchanger (3) is communicated with a first vacuum pump (4) through a pipeline, one end of the decompression rectifying tower (1) is communicated with a first air pressure sensor (18) through a pipeline, one end of the first air pressure sensor (18) is communicated with the first vacuum pump (4) through a pipeline, one end of the decompression rectification tower (1) is communicated with a nitrogen pipe (5), one end of the decompression rectification tower (1) is communicated with a nitrogen generating device through the nitrogen pipe (5), and a pipeline between the first air pressure sensor (18) and the first vacuum pump (4) is communicated with a balance air pressure pipe (6), and one end of the balance air pressure pipe (6) is communicated with an air pressure balancing device.

2. The device for reducing the content of dichloromethane in paraffin oil according to claim 1, wherein the nitrogen generation device comprises eight nitrogen bottles (7), the top of each nitrogen bottle (7) is fixedly connected with a connector (8), the top of each connector (8) is fixedly connected with a barometer, one side of each connector (8) is communicated with a gas pipe (9), eight gas pipes (9) are communicated with one end of each gas pipe (9) through a gas pressure control device (10), and one end of each gas pressure control device (10) is communicated with a nitrogen pipe (5).

3. The apparatus for reducing the content of dichloromethane in paraffin oil according to claim 2, wherein a driving motor (11) is fixedly connected to the top of the pneumatic control device (10), one end of an output shaft of the driving motor (11) penetrates through the pneumatic control device (10) and extends into the pneumatic control device (10), the driving motor (11) is located inside the pneumatic control device (10), a driving disc (17) is fixedly connected to the output shaft, and an included angle between a plane where the driving disc (17) is located and a horizontal plane is thirty degrees.

4. The device for reducing the content of dichloromethane in paraffin oil according to claim 2, wherein eight air inlet cavities (14) and eight air outlet cavities (16) are respectively formed in the air pressure control device (10), one end of each air outlet cavity (16) is communicated with the nitrogen pipe (5), an air inlet one-way valve (12) penetrates through the inner wall of each air inlet cavity (14), one end of each air inlet one-way valve (12) is communicated with the air conveying pipe (9), an air outlet one-way valve (13) penetrates through the inner wall of each air inlet cavity (14), one end of each air inlet cavity (14) is communicated with the corresponding air outlet cavity (16) through the corresponding air outlet one-way valve (13), and a piston (15) is slidably connected to the inner wall of each air inlet cavity (14).

5. The device for reducing the content of dichloromethane in paraffin oil according to claim 1, wherein the air pressure balancing device comprises a negative pressure chamber (19), one end of the negative pressure chamber (19) is communicated with an electromagnetic valve (23) through a pipeline, one end of the electromagnetic valve (23) is communicated with a balancing air pressure pipe (6), a PLC (programmable logic controller) controller (20) is fixedly connected to the top of the negative pressure chamber (19), a second air pressure sensor (21) penetrates through the top of the negative pressure chamber (19), and the output ends of the first air pressure sensor (18) and the second air pressure sensor (21) are electrically connected with the input end of the PLC controller (20) through electric wires.

6. The apparatus for reducing the content of dichloromethane in paraffin oil according to claim 5, wherein the negative pressure chamber (19) is connected to a second vacuum pump (22) through a pipeline, the output end of the PLC controller (20) is electrically connected to the input end of the second vacuum pump (22) through a wire, and the output end of the PLC controller (20) is electrically connected to the input end of the electromagnetic valve (23) through a wire.

7. The method of using the apparatus for reducing the content of methylene chloride in paraffin oil according to any of claims 1-6, comprising the steps of:

s1, a connector (8) at the tops of eight nitrogen cylinders (7) is opened, a power supply of a PLC (20) is connected, the PLC (20) controls a driving motor (11) to start, an output shaft of the driving motor (11) rotates to drive a driving disc (17) to rotate, the driving disc (17) drives eight pistons (15) to sequentially lift in the rotating process, nitrogen in the nitrogen cylinders (7) sequentially passes through the connector (8), a gas pipe (9) and an air inlet one-way valve (12) to enter an air inlet cavity (14), the nitrogen rushes into the air inlet cavity (14) to jack up the pistons (15), the driving disc (17) drives the pistons (15) to descend and compress, so that the nitrogen enters an exhaust cavity (16) through an exhaust one-way valve (13), and the nitrogen enters a reduced pressure rectifying tower (1) through a nitrogen pipe (5);

s2, after entering the bottom of the vacuum rectification tower (1), nitrogen and mixed gas of dichloromethane flow through the top heat exchanger (3) of the vacuum rectification tower (1) to be cooled, the formed liquid dichloromethane is recovered, and non-condensable gas enters a first vacuum pump (4) to continuously take away dichloromethane in paraffin oil;

s3, a first air pressure sensor (18) collects air pressure information inside a corresponding pipeline in real time and transmits the information to a PLC (programmable logic controller) controller (20), the PLC controller (20) controls a second vacuum pump (22) to start, the second vacuum pump (22) pumps air inside a negative pressure chamber (19), the second air pressure sensor (21) collects air pressure information inside the negative pressure chamber (19) in real time, the negative pressure chamber (19) transmits the air pressure information to the PLC controller (20), the PLC controller (20) controls the second vacuum pump (22) to stop when the air pressure value inside the negative pressure chamber (19) reaches a preset value, when the air pressure information transmitted by the first air pressure sensor (18) is reduced, the PLC controller (20) immediately controls an electromagnetic valve (23) to open so that the pipeline is communicated with the negative pressure chamber (19), the negative pressure inside the pipeline can be rapidly adjusted by the negative pressure chamber (19), and the negative pressure inside the pipeline can be kept in a stable range, when the negative pressure in the pipeline reaches a preset value, the PLC (20) controls the electromagnetic valve (23) to be closed.

Technical Field

The invention relates to the technical field of dichloromethane separation processes, in particular to a device for reducing the content of dichloromethane in paraffin oil.

Background

Methylene chloride is a colorless transparent liquid with an ether-like pungent odor. The methanol-ethanol composite solvent is slightly soluble in water, is soluble in ethanol and ether, is a non-flammable low-boiling point solvent, is usually used for replacing flammable petroleum ether, ether and the like, and is a compound generated by replacing two hydrogen atoms in a methane molecule by chlorine. The dichloromethane is mutually soluble with most common organic solvents, and can be mixed with other chlorine-containing solvents, ethyl ether and ethanol in any proportion. Methylene chloride can be quickly dissolved in phenol, aldehyde, ketone, glacial acetic acid, triethyl phosphate, formamide, cyclohexylamine and ethyl acetoacetate. Pure methylene chloride has no flash point, and solvent mixtures containing equal volumes of methylene chloride and gasoline, solvent naphtha or toluene are nonflammable, however when methylene chloride is mixed with acetone or methanol liquids in a 10: when mixed in a proportion of 1, the mixed solution has a flash point, and the steam and the air form an explosive mixture with an explosion limit of 6.2-15.0 percent (volume). Methylene chloride is the least toxic methane chloride and its toxicity is only 0.11% of that of carbon tetrachloride. If dichloromethane is directly splashed into eyes, the eye is painful and has a corrosive effect. The steam of methylene chloride has anesthetic effect. When a serious poisoning risk occurs, the patient should be immediately removed from contact and moved to fresh air, and some poisoning symptoms can be relieved or eliminated without causing permanent damage.

Currently in certain paraffin oil/methylene chloride separation processes: heating and separating the paraffin oil and dichloromethane mixed solution to obtain qualified dichloromethane and unqualified paraffin oil, and then carrying out reduced pressure rectification on the part of paraffin oil, wherein the reduced pressure rectification can reduce the boiling points of the paraffin oil and dichloromethane, is convenient for separation, and separates a small amount of dichloromethane and the dichloromethane-containing paraffin oil. The paraffin oil cannot be reused due to high dichloromethane content and other reasons, and is often treated as waste liquid, as shown in fig. 1, the paraffin oil produced by the process has high dichloromethane content, the concentration is as high as 500-1000 ppm, and the recovery and utilization of the paraffin oil are not facilitated, so that the development of a device for reducing the dichloromethane content in the paraffin oil is a technical problem to be solved by a person skilled in the art.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a device for reducing the content of dichloromethane in paraffin oil, and solves the problems in the background technology.

In order to achieve the purpose, the invention is realized by the following technical scheme: the utility model provides a device for reduce dichloromethane content in paraffin oil, includes decompression rectifying column, decompression rectifying column one end has the delivery pump through the pipeline intercommunication, decompression rectifying column one end has the heat exchanger through the pipeline intercommunication, heat exchanger one end has first vacuum pump through the pipeline intercommunication, decompression rectifying column one end has first baroceptor through the pipeline intercommunication, pipeline and first vacuum pump intercommunication are passed through to first baroceptor one end, decompression rectifying column one end intercommunication has the nitrogen gas pipe, decompression rectifying column one end has nitrogen gas generating device through nitrogen gas pipe intercommunication, pipeline intercommunication between first baroceptor and the first vacuum pump has balanced pneumatic tube, balanced pneumatic tube one end intercommunication has atmospheric pressure balancing unit.

Further, nitrogen gas generating device includes eight nitrogen gas bottles, nitrogen gas bottle top fixedly connected with connector, connector top fixedly connected with barometer, connector one side intercommunication has the gas-supply pipe, eight gas-supply pipe one end all communicates there is air pressure control device, air pressure control device one end and nitrogen gas pipe intercommunication.

Furthermore, a driving motor is fixedly connected to the top of the air pressure control device, one end of an output shaft of the driving motor penetrates through the air pressure control device and extends into the air pressure control device, the driving motor is located inside the air pressure control device, the output shaft of the driving motor is fixedly connected with a driving disc, and an included angle between a plane where the driving disc is located and a horizontal plane is thirty degrees.

Further, eight air inlet cavities and exhaust cavities are respectively formed in the air pressure control device, one end of each exhaust cavity is communicated with a nitrogen pipe, an air inlet one-way valve penetrates through the inner wall of each air inlet cavity, one end of each air inlet one-way valve is communicated with a gas pipe, an exhaust one-way valve penetrates through the inner wall of each air inlet cavity, one end of each air inlet cavity is communicated with the corresponding exhaust cavity through the corresponding exhaust one-way valve, and a piston is connected to the inner wall of each air inlet cavity in a sliding mode.

Further, atmospheric pressure balancing unit includes the negative pressure chamber, negative pressure chamber one end has the solenoid valve through the pipeline intercommunication, solenoid valve one end and balanced atmospheric pressure pipe intercommunication, negative pressure chamber top fixedly connected with PLC controller, the negative pressure chamber top is run through there is the second baroceptor, first baroceptor and second baroceptor output pass through electric wire and PLC controller input electric connection.

Further, the negative pressure chamber is communicated with a second vacuum pump through a pipeline, the output end of the PLC is electrically connected with the input end of the second vacuum pump through an electric wire, and the output end of the PLC is electrically connected with the input end of the electromagnetic valve through an electric wire.

The use method of the device for reducing the content of dichloromethane in paraffin oil is characterized by comprising the following steps:

s1, a connector at the tops of eight nitrogen cylinders is opened, a power supply of a PLC is connected, the PLC controls a driving motor to start, an output shaft of the driving motor rotates to drive a driving disc to rotate, the eight pistons are driven to sequentially lift in the rotating process of the driving disc, nitrogen in the nitrogen cylinders sequentially enters an air inlet cavity through the connector, an air conveying pipe and an air inlet one-way valve, the nitrogen rushes into the air inlet cavity to jack the pistons, the driving disc drives the pistons to descend and compress, so that the nitrogen enters an exhaust cavity through an exhaust one-way valve, and the nitrogen enters the interior of a decompression rectification tower through a nitrogen pipe;

s2, after nitrogen enters the bottom of the vacuum rectification tower, mixed gas flow of the nitrogen and dichloromethane is cooled by a heat exchanger at the top of the vacuum rectification tower, the partial pressure of the dichloromethane in a gas phase is reduced, the flow velocity of ascending gas flow is accelerated, the dichloromethane in paraffin oil is continuously separated, the formed liquid dichloromethane is recovered, non-condensable gas enters a first vacuum pump, the dichloromethane in the paraffin oil is continuously taken away, the content of the dichloromethane in the produced paraffin oil is effectively reduced, the concentration is lower than 100ppm, the recovery and utilization of the paraffin oil are facilitated, and the production cost is reduced;

s3 the first air pressure sensor collects air pressure information corresponding to the inside of the pipeline in real time and transmits the information to the PLC, the PLC controls the second vacuum pump to start, the second vacuum pump pumps out air inside the negative pressure chamber, the second air pressure sensor collects air pressure information inside the negative pressure chamber in real time, the negative pressure chamber transmits the air pressure information to the PLC, the PLC controls the second vacuum pump to stop when the air pressure value inside the negative pressure chamber reaches a preset value, when the air pressure information sent back by the first air pressure sensor is reduced, the PLC immediately controls the electromagnetic valve to be opened, the pipeline is communicated with the negative pressure chamber, the negative pressure inside the pipeline can be rapidly adjusted by the negative pressure chamber, the negative pressure inside the pipeline is kept in a stable range, and when the negative pressure inside the pipeline reaches the preset value, the PLC controls the electromagnetic valve to be closed.

The invention has the following beneficial effects:

1. this reduce device of dichloromethane content in paraffin oil lets in nitrogen gas through nitrogen gas generating device to decompression rectifying column inside, reduces the partial pressure of dichloromethane in the gas phase, accelerates the updraft velocity of flow simultaneously, makes dichloromethane continuously separate in the paraffin oil, has effectively reduced dichloromethane content in the output paraffin oil, and concentration is low to below 100ppm, compares with prior art, does benefit to the recycle of paraffin oil, reduction in production cost.

2. This reduce device of dichloromethane content in paraffin oil through inserting atmospheric pressure balancing unit, can effectively balance the inside negative pressure of pipe-line system for the inside negative pressure of pipeline is stable, and guarantee dichloromethane can continuously separate.

Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural view of a conventional methylene chloride production apparatus;

FIG. 2 is a schematic structural diagram of an apparatus for reducing the content of methylene chloride in paraffin oil according to the present invention;

FIG. 3 is a schematic structural diagram of an air pressure generating device;

FIG. 4 is a schematic view of the internal structure of the pneumatic control device;

fig. 5 is a schematic view of the internal structure of the negative pressure chamber.

In the drawings, the components represented by the respective reference numerals are listed below:

in the figure: 1-a reduced pressure rectifying tower, 2-a conveying pump, 3-a heat exchanger, 4-a first vacuum pump, 5-a nitrogen gas pipe, 6-a balance air pressure pipe, 7-a nitrogen gas bottle, 8-a connector, 9-an air conveying pipe, 10-an air pressure control device, 11-a driving motor, 12-an air inlet one-way valve, 13-an air outlet one-way valve, 14-an air inlet cavity, 15-a piston, 16-an air outlet cavity, 17-a driving disc, 18-a first air pressure sensor, 19-a negative pressure chamber, 20-a PLC (programmable logic controller), 21-a second air pressure sensor, 22-a second vacuum pump and 23-an electromagnetic valve.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-5, the present invention provides a technical solution: the utility model provides a device of dichloromethane content in reduction paraffin oil, including decompression rectifying column 1, decompression rectifying column 1 one end has KCB83-001 model delivery pump 2 through the pipeline intercommunication, decompression rectifying column 1 one end has heat exchanger 3 through the pipeline intercommunication, heat exchanger 3 one end has the first vacuum pump 4 of KCB83-001 model through the pipeline intercommunication, decompression rectifying column 1 one end has the first air pressure sensor 18 of TJP-1 model through the pipeline intercommunication, first air pressure sensor 18 one end is through pipeline and first vacuum pump 4 intercommunication, decompression rectifying column 1 one end intercommunication has nitrogen pipe 5, decompression rectifying column 1 one end has nitrogen gas generating device through nitrogen pipe 5 intercommunication, the pipeline intercommunication between first air pressure sensor 18 and the first vacuum pump 4 has balanced pneumatic tube 6, balanced pneumatic tube 6 one end intercommunication has the atmospheric pressure balancing unit.

Wherein, nitrogen gas generating device includes eight nitrogen gas bottles 7, and 7 top fixedly connected with connectors 8 of nitrogen gas bottle, 8 top fixedly connected with barometer of connector, 8 one side intercommunications of connector have gas-supply pipe 9, and eight gas-supply pipe 9 one ends all communicate there is atmospheric control device 10, and atmospheric control device 10 one end communicates with nitrogen gas pipe 5.

Wherein, air pressure control device 10 top fixedly connected with driving motor 11, 11 output shaft one end of driving motor runs through air pressure control device 10 and extend to inside air pressure control device 10, driving motor 11 is located the inside output shaft fixedly connected with driving-disc 17 of air pressure control device 10, driving-disc 17 place plane and horizontal plane contained angle are thirty degrees, PLC controller 20 output passes through electric wire and 11 input electric connection of driving motor.

Wherein, eight air inlet cavities 14 and exhaust cavities 16 have been seted up respectively to atmospheric pressure controlling means 10 inside, 16 one ends of exhaust cavities communicate with nitrogen gas pipe 5, 14 inner walls of air inlet cavities have run through the single valve 12 of admitting air, 12 one ends of the single valve 12 of admitting air communicate with the gas-supply pipe 9, 14 inner walls of air inlet cavities have run through the exhaust check valve 13, 14 one ends of air inlet cavities communicate with 16 of exhaust cavities through the exhaust check valve 13, 14 inner walls of air inlet cavities sliding connection has piston 15.

Wherein, atmospheric pressure balancing unit includes negative pressure chamber 19, and negative pressure chamber 19 one end has solenoid valve 23 through the pipeline intercommunication, and solenoid valve 23 one end and balanced pneumatic tube 6 intercommunication, 19 top fixedly connected with MSFLYER3 model PLC controller 20 of negative pressure chamber, 19 top penetrations of negative pressure chamber have TJP-1 model second baroceptor 21, and first baroceptor 18 and second baroceptor 21 output pass through electric wire and PLC controller 20 input electric connection.

The negative pressure chamber 19 is communicated with a second vacuum pump 22 of KCB83-001 model through a pipeline, the output end of the PLC controller 20 is electrically connected with the input end of the second vacuum pump 22 through an electric wire, and the output end of the PLC controller 20 is electrically connected with the input end of the electromagnetic valve 23 through an electric wire.

The use method of the device for reducing the content of dichloromethane in paraffin oil is characterized by comprising the following steps:

s1, the connector 8 at the tops of the eight nitrogen cylinders 7 is opened, a power supply of the PLC 20 is connected, the PLC 20 controls the driving motor 11 to start, an output shaft of the driving motor 11 rotates to drive the driving disc 17 to rotate, the driving disc 17 drives the eight pistons 15 to sequentially lift in the rotating process, nitrogen in the nitrogen cylinders 7 sequentially enters the air inlet cavity 14 through the connector 8, the air conveying pipe 9 and the air inlet one-way valve 12, the nitrogen rushes into the air inlet cavity 14 to jack up the pistons 15, the driving disc 17 drives the pistons 15 to descend and compress, so that the nitrogen enters the air outlet cavity 16 through the exhaust one-way valve 13, and the nitrogen enters the inside of the reduced-pressure rectifying tower 1 through the nitrogen pipe 5;

s2, after nitrogen enters the bottom of the decompression rectifying tower 1, mixed gas of the nitrogen and dichloromethane is cooled by the heat exchanger 3 at the top of the decompression rectifying tower 1, the formed liquid dichloromethane is recovered, and non-condensable gas enters the first vacuum pump 4 to continuously take away dichloromethane in paraffin oil;

s3 the first air pressure sensor 18 collects air pressure information of the inside of the corresponding pipe in real time and transmits the information to the PLC controller 20, the PLC controller 20 controls the second vacuum pump 22 to start, the second vacuum pump 22 pumps out air in the negative pressure chamber 19, the second air pressure sensor 21 collects air pressure information in the negative pressure chamber 19 in real time, the negative pressure chamber 19 transmits the air pressure information to the PLC controller 20, when the air pressure value inside the negative pressure chamber 19 reaches a preset value, the PLC controller 20 controls the second vacuum pump 22 to stop, when the air pressure information transmitted back by the first air pressure sensor 18 is reduced, the PLC controller 20 immediately controls the electromagnetic valve 23 to be opened, so that the pipeline is communicated with the negative pressure chamber 19, the negative pressure chamber 19 can rapidly adjust the negative pressure in the pipeline to keep the negative pressure in the pipeline in a stable range, when the negative pressure in the pipeline reaches a preset value, the PLC 20 controls the electromagnetic valve 23 to be closed.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.