Energy-saving production device for refining and deoxidizing liquid chlorine

Abstract

The utility model discloses an energy-saving production device for refining and deoxidizing liquid chlorine, which belongs to the technical field of liquid chlorine refining and comprises a chlorine heating device, a chlorine and liquid chlorine hedging and impurity removing device, a chlorine liquefying device and a liquid chlorine circulating device. The chlorine heating device is used for conveying high-temperature chlorine into the chlorine liquid chlorine hedging and impurity removing device through a pipeline; the liquid chlorine circulating device is used for continuously conveying liquid chlorine into the chlorine and liquid chlorine hedging and impurity removing device through a pipeline; in the chlorine and liquid chlorine hedging and impurity removing device, liquid chlorine absorbs high-temperature chlorine to be vaporized and then completes countercurrent hedging with continuously conveyed liquid chlorine, impurities in the liquid chlorine are taken away, and the liquid chlorine subjected to impurity removal is conveyed to a user side through a pipeline. The liquid chlorine refining and deoxidizing energy-saving production device can effectively solve the problems that in the prior art, heat of high-temperature chlorine at an outlet of a chlorine compressor is not effectively utilized in the liquid chlorine refining process, and sensible heat of the high-temperature chlorine is wasted; in the refining process, steam needs to be additionally introduced as a heat source, and the steam consumption is large.

Description

TECHNICAL FIELD

[0001] The utility model belongs to liquid chlorine refining technical field, specifically relates to a kind of liquid chlorine refining deoxygenation energy-saving production device. BACKGROUND

[0002] Liquid chlorine is one of main products of ion-exchange membrane caustic soda device, and its use is very extensive, and it is raw material for producing methane chlorides, TDI, MDI and other products.In the process of electrolysis, OH - Will return to anode from cathode, and side reaction occurs to generate oxygen, which causes the purity of chlorine gas at the outlet of anode in electrolysis to decrease.In the process of chlorine liquefaction, part of oxygen and other non-condensable gases are discharged with tail gas, which will increase the purity of liquid chlorine to some extent, but part of oxygen still exists in liquid chlorine, which finally leads to the purity of liquid chlorine failing to meet the requirements of some production devices with high quality requirements for liquid chlorine, and further deoxygenation is needed.

[0003] At present, the process of liquid chlorine deoxygenation commonly used in chlor-alkali industry is as follows: chlorine gas is compressed to a certain pressure by chlorine compressor to obtain high-temperature chlorine gas at about 90 DEG C;the high-temperature chlorine gas is cooled to about 45 DEG C by circulating water and then sent to liquefier, in which the chlorine gas is further heat-exchanged with refrigerant to condense and liquefy the chlorine gas to obtain crude liquid chlorine;the oxygen content in crude liquid chlorine is about 400-600 ppmwt (different with different liquefaction pressure), and the crude liquid chlorine is sent to liquid chlorine refining tower for deoxygenation by liquid chlorine pump;usually, the liquid chlorine refining tower is equipped with bottom reboiler, and uses live steam as heat source;the crude liquid chlorine enters from the top of the tower, and is countercurrently contacted with vaporized chlorine from the bottom reboiler of the tower to carry out mass transfer and heat exchange;in this process, the oxygen-rich liquid chlorine is refined by using the difference in boiling points of chlorine and oxygen, and finally the deoxygenated refined liquid chlorine is obtained at the bottom of the tower.This process can improve the purity of liquid chlorine, but has certain limitations:the heat of high-temperature chlorine gas at the outlet of compressor is not effectively utilized, and the sensible heat of high-temperature chlorine gas is wasted by using circulating water for cooling, which increases the consumption of circulating water;additional steam needs to be introduced for stripping in the refining process, and the steam consumption is large for large-scale liquid chlorine refining device. UTILITY MODEL CONTENT

[0004] The utility model aims at the above-mentioned insufficient place and provides a kind of liquid chlorine refining deoxygenation energy-saving production device to solve the problem that the heat of high-temperature chlorine gas at the outlet of chlorine compressor is not effectively utilized in the liquid chlorine refining process in prior art, and the sensible heat of high-temperature chlorine gas is wasted by using circulating water for cooling, which increases the consumption of circulating water;additional steam needs to be introduced for stripping in the refining process as heat source.For large-scale liquid chlorine refining device, the steam consumption is large and other problems are solved.To achieve the above-mentioned purpose, the utility model provides the following technical scheme:

[0005] The application discloses a kind of liquid chlorine refining deoxidation energy-saving production device, including chlorine gas heating device, chlorine gas liquid chlorine opposite impurity removal device, chlorine gas liquefaction device and liquid chlorine circulation device;The high-temperature chlorine gas is transported to chlorine gas liquid chlorine opposite impurity removal device by pipeline by the chlorine gas heating device;The liquid chlorine is continuously transported to chlorine gas liquid chlorine opposite impurity removal device by pipeline by the liquid chlorine circulation device;In chlorine gas liquid chlorine opposite impurity removal device, the liquid chlorine absorbs the temperature vaporization of high-temperature chlorine gas and completes countercurrent opposite with the liquid chlorine of continuous transport, removes the impurity in liquid chlorine, and the liquid chlorine after impurity removal is transported to user end by pipeline;The low-temperature chlorine gas is transported to chlorine gas liquefaction device by pipeline after the high-temperature chlorine gas heat exchange, and the liquid chlorine vaporization is transported to chlorine gas liquefaction device by pipeline;The liquid chlorine in the chlorine gas liquefaction device is transported to liquid chlorine circulation device by pipeline.

[0006] Further, the chlorine gas heating device includes a chlorine gas compressor; the gas inlet end of the chlorine gas compressor is connected to the raw material chlorine gas, and the output end outputs high-temperature chlorine gas.

[0007] Further, the chlorine gas liquid chlorine opposite impurity removal device includes a liquid chlorine reboiler and a liquid chlorine refining tower; the liquid chlorine reboiler is arranged at the bottom end of the liquid chlorine refining tower and includes a shell side and a tube side; the high-temperature chlorine gas is transported to the inlet of the shell side by pipeline, and the low-temperature chlorine gas is output from the outlet of the shell side.

[0008] Further, the chlorine gas liquefaction device includes a chlorine gas liquefier; the low-temperature chlorine gas is liquefied in the chlorine gas liquefier by pipeline.

[0009] Further, the liquid chlorine circulation device includes a liquid chlorine storage tank and a liquid chlorine pump; the output end of the chlorine gas liquefier is connected to the liquid chlorine storage tank by pipeline; and the liquid chlorine storage tank is connected to the upper part of the liquid chlorine refining tower by the liquid chlorine pump.

[0010] Further, the liquid chlorine transported by the liquid chlorine storage tank flows into the tube side of the liquid chlorine reboiler through the upper part of the liquid chlorine refining tower and is heat-exchanged with the high-temperature chlorine gas in the shell side.

[0011] Further, the liquid chlorine in the tube side is vaporized after absorbing heat and forms chlorine gas which moves to the top of the liquid chlorine refining tower and is in countercurrent contact with the liquid chlorine flowing into the upper part of the liquid chlorine refining tower; the chlorine gas and the impurity gas in the liquid chlorine are transported to the chlorine gas liquefier through the top of the liquid chlorine refining tower.

[0012] Further, the bottom of the liquid chlorine refining tower is provided with a liquid chlorine outlet.

[0013] Further, the liquid chlorine separator is further included; the feed inlet of the liquid chlorine separator is connected to the discharge outlet of the chlorine gas liquefier by pipeline, and the discharge outlet of the liquid chlorine separator is connected to the liquid chlorine storage tank by pipeline.

[0014] Further, the liquid chlorine separator is provided with a liquefied tail gas outlet and a blowdown outlet.

[0015] The utility model discloses the beneficial effect is:

[0016] The utility model discloses a kind of liquid chlorine refining deoxidation energy-saving production devices, high temperature chlorine gas is cooled by the mode of heat exchange with liquid chlorine. Make full use of sensible heat of high temperature chlorine gas, sensible heat of high temperature chlorine gas is used as heat source to vaporize liquid chlorine, it is not needed to consume cooling water to cool chlorine gas additionally, also not need steam to vaporize liquid chlorine, can reduce operating cost and energy consumption;Cooling of raw material chlorine gas and vaporization of liquid chlorine are realized by a liquid chlorine reboiler, process is simple, and equipment is less. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is the utility model structure schematic diagram;

[0018] In the drawing, 1-chlorine compressor;2-liquid chlorine reboiler;3-liquid chlorine refining tower;4-chlorine liquefier;5-liquid chlorine separator;6-liquid chlorine storage tank;7-liquid chlorine pump;a1-raw material chlorine;a2-high temperature chlorine;a3-low temperature chlorine;a4-refined tail gas;b1-liquid chlorine;b2-refined liquid chlorine;c-liquefied tail gas;d-discharge. DETAILED DESCRIPTION

[0019] The utility model is further detailed below in connection with the drawing and specific embodiment. To make the purpose, technical scheme and advantage of the utility model embodiment more clear, the technical scheme in the utility model embodiment will be clearly and completely described below in connection with the drawing in the utility model embodiment. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiment. The components of the utility model embodiment described and shown in the drawing here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the utility model provided in the drawing is not intended to limit the scope of the claimed utility model, but only represents selected embodiment of the utility model. Based on the embodiment in the utility model, all other embodiments obtained by ordinary skilled person in the art without making creative effort belong to the scope of the utility model protection.

[0020] It should be noted that similar reference numerals and letters refer to similar items in the following drawings, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings. In the description of the present application, it should be explained that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed during use, and are merely for the convenience of describing the present application and simplifying the description, and therefore, cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore, cannot be understood as limiting the present application. In addition, the terms "first", "second", "third", and the like are only used for differentiation in description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", and the like do not mean that the components must be absolutely horizontal or vertical, but can be slightly inclined. For example, "horizontal" only means that its direction is relatively more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined. In the description of the present application, it should be explained that, unless otherwise explicitly specified and limited, the terms "provided", "mounted", "connected", "linked" should be understood in a broad sense, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, can be electrically connected; can be directly connected, can be indirectly connected through an intermediate medium, or can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0021] Embodiment:

[0022] See the attached Figure 1The application discloses a liquid chlorine refining deoxidization energy-saving production device, which is based on the improvement of a liquid chlorine refining deoxidization process in the prior art, and heat of high-temperature chlorine gas after compression by a chlorine compressor 1 is fully utilized by canceling live steam as a heat source. The device comprises a chlorine gas heating device, a chlorine-liquid chlorine counterflow impurity removal device, a chlorine liquefaction device and a liquid chlorine circulating device. The chlorine gas heating device is used for heating raw material chlorine gas into high-temperature chlorine gas at about 90 DEG C, and is preferably the chlorine compressor 1. The temperature of the raw material chlorine gas is about 15-20 DEG C. After compression by the chlorine compressor 1 to a certain pressure, high-temperature chlorine gas at about 90 DEG C is obtained. The high-temperature chlorine gas enters the chlorine-liquid chlorine counterflow impurity removal device through a pipeline. The liquid chlorine circulating device continuously delivers liquid chlorine to the chlorine-liquid chlorine counterflow impurity removal device. In the chlorine-liquid chlorine counterflow impurity removal device, the compressed high-temperature chlorine gas exchanges heat with the liquid chlorine. After heat release, the high-temperature chlorine gas forms low-temperature chlorine gas which is delivered to the chlorine liquefaction device. After heat exchange with the high-temperature chlorine gas, the liquid chlorine is partially vaporized to form chlorine gas, and counterflows with the liquid chlorine continuously input into the chlorine-liquid chlorine counterflow impurity removal device to perform mass transfer and heat exchange. In this process, the oxygen-rich liquid chlorine is refined by utilizing the boiling point difference between chlorine gas and oxygen gas. The vaporized chlorine gas carries away oxygen, nitrogen and carbon dioxide and other gas impurities in the liquid chlorine and is delivered to the chlorine liquefaction device. At this time, the impurity gas in the liquid chlorine is removed to form refined liquid chlorine which is discharged from the bottom of the chlorine-liquid chlorine counterflow impurity removal device to a user end for use. The low-temperature chlorine gas after heat exchange with the high-temperature chlorine gas and the chlorine gas carrying impurities after vaporization of the liquid chlorine are delivered to the chlorine liquefaction device together to further recover chlorine gas, and form liquid chlorine by liquefaction and store in the chlorine circulating device.

[0023] The chlorine-liquid chlorine counterflow impurity removal device specifically comprises a liquid chlorine reboiler 2 and a liquid chlorine refining tower 3. The liquid chlorine reboiler 2 is directly connected to the bottom of the liquid chlorine refining tower 3. The high-temperature chlorine gas flows in the shell side of the liquid chlorine reboiler 2, and the liquid chlorine delivered by the liquid chlorine circulating device is in the tube side. In the shell side, the raw material high-temperature chlorine gas is cooled to 30-40 DEG C, and then is delivered to the chlorine liquefaction device to exchange heat with a refrigerant and be cooled to about -20-17 DEG C (changes according to the liquefaction pressure), and is liquefied into liquid chlorine. In the tube side, the liquid chlorine is partially vaporized to form chlorine gas by heat absorption and boiling, and the chlorine gas rises to the top of the liquid chlorine refining tower 3 to contact and mass transfer with the liquid chlorine continuously input from one side of the top, and carries away most of the impurity gas in the liquid chlorine, such as oxygen, nitrogen and carbon dioxide, from the top of the liquid chlorine refining tower 3 to the chlorine liquefaction device to recover chlorine gas. The unvaporized liquid chlorine flows to the bottom of the liquid chlorine reboiler 2 to be discharged as refined liquid chlorine and output to a user end for use.

[0024] The chlorine gas liquefaction device recovers the chlorine gas carrying impurities and the low-temperature chlorine gas after heat exchange and performs liquefaction, and is preferably a chlorine gas liquefier 4. A liquid chlorine separator 5 is arranged at the output end of the chlorine gas liquefier 4 to separate liquid chlorine and liquefied tail gas, and oxygen and other gases are discharged with the liquefied tail gas. With the discharge of the liquefied tail gas, the impurities in the liquid chlorine are reduced, the purity is improved, and periodic blowdown is performed at the bottom of the liquid chlorine separator 5, thereby avoiding the accumulation of nitrogen trichloride.

[0025] The liquid chlorine circulating device comprises a liquid chlorine storage tank 6 and a liquid chlorine pump 7. The liquid chlorine separated by the liquid chlorine separator 5 is delivered to the liquid chlorine storage tank 6 through a pipeline for buffering. The output end of the liquid chlorine storage tank 6 is connected to one side of the top of the liquid chlorine refining tower 3 through a pipeline. The liquid chlorine pump 7 is connected in the pipeline between the liquid chlorine storage tank 6 and the liquid chlorine refining tower 3. The liquid chlorine in the liquid chlorine storage tank 6 is pumped into the liquid chlorine refining tower 3 by the liquid chlorine pump 7. The liquid chlorine in the liquid chlorine refining tower 3 is countercurrently contacted with the vaporized chlorine gas at the upper part of the liquid chlorine refining tower 3 for mass transfer to remove part of the impurities and then enters the liquid chlorine reboiler 2. Part of the liquid chlorine that is not vaporized is discharged as refined liquid chlorine.

[0026] The working process of the utility model is as follows: the raw material chlorine gas is compressed to 0.2-0.7MPaG by the chlorine gas compressor 1. During the compression process, the temperature of the raw material chlorine gas is increased to about 90 DEG C. The high-temperature chlorine gas at the outlet of the chlorine gas compressor 1 is then sent to the shell side of the liquid chlorine reboiler 2 to exchange heat with the liquid chlorine at the tube side, and the chlorine gas is cooled to about 30-40 DEG C. The low-temperature chlorine gas after cooling is then sent to the liquefier to exchange heat with the refrigerant and is cooled to about-20-17 DEG C (corresponding to the change of the liquefaction pressure), and the chlorine gas is liquefied into liquid chlorine and then flows into the liquid chlorine separator 5 by itself. The liquid chlorine and the liquefied tail gas are separated, and oxygen and other gases are discharged with the liquefied tail gas. The liquid chlorine flows into the liquid chlorine storage tank 6. In the liquid chlorine separator 5, periodic blowdown can also be performed at the bottom of the liquid chlorine separator 5, thereby avoiding the accumulation of nitrogen trichloride. The liquid chlorine is buffered in the liquid chlorine storage tank 6 and is delivered to the upper part of the liquid chlorine refining tower 3 by the liquid chlorine pump 7. After the liquid chlorine enters the liquid chlorine refining tower 3, the liquid chlorine is countercurrently contacted with the vaporized chlorine from the liquid chlorine reboiler 2 for mass transfer. The vaporized chlorine gas rises to the top of the tower as refined tail gas and is then delivered to the chlorine gas liquefier 4 for further liquefaction to recover the chlorine in the tail gas. The liquid chlorine at the bottom of the liquid chlorine refining tower 3 enters the liquid chlorine reboiler 2, is partially vaporized after absorbing the heat released by the raw material chlorine gas, rises to the top of the liquid chlorine refining tower 3 to refine the liquid chlorine, and the liquid chlorine that is not vaporized flows to the bottom of the reboiler and is discharged as refined liquid chlorine.

[0027] The above description is only the preferred embodiment of the utility model, and does not limit the patent range of the utility model. Any equivalent structure or equivalent process conversion or direct or indirect application in other related technical fields based on the content of the utility model specification and drawings is also included in the patent protection range of the utility model.

Claims

1. A liquid chlorine refining and deoxygenation energy-saving production device, characterized in that: The application relates to a chlorine gas heating device, a chlorine gas and liquid chlorine collision impurity removal device, a chlorine gas liquefaction device and a liquid chlorine circulation device.

2. The energy-saving device for producing liquid chlorine by deoxidizing and purifying according to claim 1, characterized in that: The chlorine gas heating device comprises a chlorine gas compressor (1); the gas inlet end of the chlorine gas compressor (1) is connected with raw chlorine gas, and the output end outputs high-temperature chlorine gas.

3. The energy-saving device for producing liquid chlorine by deoxidizing and purifying according to claim 2, characterized in that: The chlorine gas and liquid chlorine collision impurity removal device comprises a liquid chlorine reboiler (2) and a liquid chlorine refining tower (3); the liquid chlorine reboiler (2) is arranged at the bottom end of the liquid chlorine refining tower (3) and comprises a shell side and a tube side; the high-temperature chlorine gas is transported to the inlet of the shell side through a pipeline, and the outlet of the shell side outputs low-temperature chlorine gas.

4. The energy-saving device for producing liquid chlorine by deoxidizing and purifying according to claim 3, characterized in that: The chlorine gas liquefaction device comprises a chlorine gas liquefier (4); the low-temperature chlorine gas is transported to the chlorine gas liquefier (4) through a pipeline.

5. The energy-saving device for producing liquid chlorine by deoxidizing and purifying according to claim 4, characterized in that: The liquid chlorine circulation device comprises a liquid chlorine storage tank (6) and a liquid chlorine pump (7); the output end of the chlorine gas liquefier (4) is connected with the liquid chlorine storage tank (6) through a pipeline; and the liquid chlorine storage tank (6) is connected with the upper portion of the liquid chlorine refining tower (3) through the liquid chlorine pump (7).

6. The energy-saving device for producing liquid chlorine by deoxidizing and purifying according to claim 5, characterized in that: The liquid chlorine transported by the liquid chlorine storage tank (6) flows into the tube side of the liquid chlorine reboiler (2) through the upper portion of the liquid chlorine refining tower (3) and is heat-exchanged with the high-temperature chlorine gas in the shell side.

7. The energy-saving device for producing liquid chlorine by deoxidizing and purifying according to claim 6, characterized in that: The liquid chlorine in the tube side is heat-absorbed and vaporized to form chlorine gas which moves to the top of the liquid chlorine refining tower (3) and is in countercurrent contact with the liquid chlorine flowing into the upper portion of the liquid chlorine refining tower (3), so that the chlorine gas and the impurity gas in the liquid chlorine are transported to the chlorine gas liquefier (4) through the top of the liquid chlorine refining tower (3).

8. The energy-saving production device for refining and deoxidizing liquid chlorine according to claim 7, characterized in that: The bottom of the liquid chlorine refining tower (3) is provided with a liquid chlorine outlet.

9. The energy-saving device for producing liquid chlorine by deoxidizing and purifying according to claim 8, characterized in that: The liquid chlorine separator (5) is further provided with a liquefied tail gas outlet and a blowdown outlet.

10. The energy-saving device for producing liquid chlorine by deoxidizing and refining according to claim 9, characterized in that: ​

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