CN112007371A

CN112007371A - Carbon dioxide purification device and feeding method thereof

Info

Publication number: CN112007371A
Application number: CN202010805825.6A
Authority: CN
Inventors: 石唯; 徐琨璘; 陈培滋; 刘峰
Original assignee: Huizhou Huadatong Gas Manufacturing Co Ltd
Current assignee: Huizhou Huadatong Gas Manufacturing Co Ltd
Priority date: 2020-08-12
Filing date: 2020-08-12
Publication date: 2020-12-01
Anticipated expiration: 2040-08-12
Also published as: CN112007371B

Abstract

The application provides a carbon dioxide purification device and a purification device feeding method, wherein the carbon dioxide purification device comprises a rectifying tower, a first feeding and discharging assembly and a condenser; the inner cavity of the rectifying tower comprises a rectifying section and a stripping section which are distributed up and down along the axis; the first feeding and discharging assembly comprises a first feeding pipe, a first discharging pipe and a return pipe, and the first discharging pipe is connected with the top of the rectifying tower; taking the position of the connection part of the first feeding pipe and the rectifying tower as A, the central line of the rectifying tower along the axial direction as B, the position of the bottom of the rectifying tower as C, wherein A is positioned between the rectifying section and the stripping section, and the distance between A and B is less than the distance between A and C; one end of the condenser is connected with one end, far away from the rectifying tower, of the first discharging pipe, the other end of the condenser is connected with the rectifying tower through a return pipe, and the joint of the return pipe and the rectifying tower is located between the rectifying section and the joint of the first discharging pipe and the rectifying tower. The application provides a carbon dioxide purification device can effectively improve product purification efficiency.

Description

Carbon dioxide purification device and feeding method thereof

Technical Field

The application belongs to the technical field of chemical equipment, and particularly relates to a carbon dioxide purification device and a feeding method of the purification device.

Background

In today's carbon dioxide purification processes, a rectification column is typically used to purify a carbon dioxide feed containing impurities. The rectification tower is a tower-type gas-liquid contact device for rectification, and the principle of the rectification tower is that light component substances, namely low-boiling-point substances, in a liquid phase are transferred into a gas phase, and heavy components (high-boiling-point substances) in the gas phase are transferred into the liquid phase by utilizing the property that each component in a mixture has different volatility, namely the vapor pressure of each component is different at the same temperature, so that the aim of separating each substance component is fulfilled. However, in actual production, the raw material fed into the rectifying column through one feed pipe may have different thermal states, thereby causing the rectifying column to have different feeding conditions. Under different feeding conditions, the reflux quantity of a stripping section in the rectifying tower and the gas-liquid balance in the rectifying tower are obviously influenced, so that the purification efficiency of the rectifying tower is adversely affected.

Disclosure of Invention

An object of the embodiment of this application is to provide a carbon dioxide purification device to solve the technical problem that exists among the prior art because of the lower purification efficiency that the single feed mode leads to of carbon dioxide purification technology.

In order to achieve the purpose, the technical scheme adopted by the application is as follows: provided is a carbon dioxide purification apparatus including:

the inner cavity of the rectifying tower comprises a rectifying section and a stripping section which are distributed along the axial direction, and the rectifying section is positioned above the stripping section;

the first feeding and discharging assembly comprises a first feeding pipe, a first discharging pipe and a return pipe, and the first discharging pipe is connected with the top of the rectifying tower; taking the position of the connection part of the first feeding pipe and the rectifying tower as A, the central line of the rectifying tower along the axial direction as B, the position of the bottom of the rectifying tower as C, wherein A is positioned between the rectifying section and the stripping section, and the distance between A and B is less than the distance between A and C; and the number of the first and second groups,

the condenser, the one end of condenser with first discharging pipe is kept away from the one end of rectifying column is connected, the other end of condenser passes through the back flow with the rectifying column is connected, just the back flow with the junction of rectifying column is located the rectifying section with first discharging pipe with between the junction of rectifying column.

Optionally, the carbon dioxide purification device further comprises a reboiler and a second feed and discharge assembly;

place in the reboiler in the inner chamber of rectifying column, and be located the below of stripping section, second business turn over material subassembly is including the second inlet pipe, second heating pipe and the second discharging pipe that connect gradually, place in the second heating pipe in the reboiler, the one end of second inlet pipe stretch into back in the rectifying column with the second heating pipe is connected, the one end of second discharging pipe with the second heating pipe is kept away from the one end of second inlet pipe is connected, the other end of second discharging pipe stretch out behind the rectifying column with first inlet pipe is connected.

Optionally, the carbon dioxide purification device further comprises a third inlet and outlet assembly; the third feeding and discharging assembly comprises a third feeding pipe, a third heating pipe and a third discharging pipe which are connected in sequence, the third heating pipe is arranged in the reboiler, one end of the third feeding pipe extends into the rectifying tower and then is connected with the third heating pipe, one end of the third discharging pipe is connected with one end, far away from the third feeding pipe, of the third heating pipe, and the other end of the third discharging pipe extends out of the rectifying tower and then is connected with the condenser;

the second heating pipe and the third heating pipe are arranged independently of each other in the reboiler.

Optionally, the condenser has a first cooling conduit and a second cooling conduit independent of each other; one end of the first cooling pipeline is connected with the first discharge pipe, and the other end of the first cooling pipeline is connected with the return pipe; the inlet end of the second cooling pipeline is connected with the third discharge pipe.

Optionally, a backflow regulating valve group is arranged on the backflow pipe.

Optionally, the backflow regulating valve group comprises a first regulating valve, a second regulating valve and a third regulating valve, and the first regulating valve, the second regulating valve and the third regulating valve are sequentially arranged along the direction from the condenser to the pipeline direction of the rectifying tower through the backflow pipe.

Optionally, the first feeding and discharging assembly further comprises a return branch pipe, and the joints of the two ends of the return branch pipe and the return pipe are respectively located between the first regulating valve and the condenser, and between the third regulating valve and the rectifying tower; the backflow regulating valve group further comprises a fourth regulating valve, and the fourth regulating valve is arranged on the backflow branch pipe.

The present application also proposes a purification plant feeding method, which is carried out using a carbon dioxide purification plant as described previously, comprising a first feeding pipe for a gaseous feed and a second feeding pipe for a liquid feed, said purification plant feeding method comprising the following steps:

s1, acquiring a feeding hot state parameter q of the raw material entering the rectifying tower, and dividing the raw material entering the rectifying tower into a cold liquid feeding state with q being greater than 1, a saturated liquid feeding state with q being 1, a gas-liquid mixture feeding state with q being greater than 0 and less than 1, a saturated steam feeding state with q being 0 and a superheated steam feeding state with q being less than 0 according to a q value;

s2, when the cold liquid feeding state, the saturated liquid feeding state and the gas-liquid mixture feeding state are adopted, the raw material enters a reboiler at the bottom of the rectifying tower from the second feeding pipe, is heated and converted into a gas state, and then enters the first feeding pipe; the raw material enters the rectifying tower from the first feeding pipe in the saturated steam feeding state and the superheated steam feeding state;

s3, adjusting the reflux ratio R on the reflux pipe according to the q value.

Alternatively, in the step S2, the feeding needs to satisfy the following feeding conditions:

y＝﹛q/(q-1)﹜x-﹛1/(q-1)﹜xF

wherein q ═ L' -L)/F; x is the mole fraction of the raw material; f is the flow rate of the raw material; l is the mass flow rate of the descending vapor substance of each tower plate in the rectifying section of the rectifying tower; l' is the mass flow rate of vapor species descending per tray in the stripping section in the rectification column.

Optionally, the feedstock enters the rectification column in the saturated steam feed state.

The application provides a carbon dioxide purification device's beneficial effect lies in: compared with the prior art, in the carbon dioxide purification device, after the raw material enters the rectifying tower from the first feeding pipe, the gaseous component containing impurities in the raw material rises upwards and passes through the rectifying section, then comes out from the top of the rectifying tower and enters the condenser through the first discharging pipe; then, in the condenser, the top distillate of the tower, of which the temperature of the gaseous components is reduced and converted into the liquid state, flows out from one end of the condenser, which is far away from the first discharge pipe, and meanwhile, according to different heat states of the raw materials, part of the liquid components flow back to the top of the rectifying tower from the return pipe and flow downwards from the top of the rectifying tower through the rectifying section. In this application, because the junction A of first inlet pipe and rectifying column is located between rectifying section and the stripping section, and this junction A and rectifying column central line B's distance little and A and the rectifying column bottom of the tower C's distance, the junction of first inlet pipe and rectifying column promptly should be the well lower part that is located the rectifying column, thus, just can ensure that the height of rectifying section is greater than the height of stripping section far away, thereby increased from the back flow in the liquid of backward flow at rectifying section department with the contact path length of gaseous phase, and then can make the raw materials when the hot state of difference, the homoenergetic enough obtains effectual separation purification, and then improved the purification efficiency of this carbon dioxide purification device.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic structural diagram of a carbon dioxide purification apparatus provided in an embodiment of the present application;

fig. 2 is a flow chart of a feeding method of a purification device provided in an embodiment of the present application.

The reference numbers illustrate:

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It should be noted that the terms of orientation such as left, right, up and down in the embodiments of the present application are only relative to each other or are referred to the normal use state of the product, and should not be considered as limiting.

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application and should not be construed as limiting the present application.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, as used herein, refer to an orientation or positional relationship indicated in the drawings that is solely for the purpose of facilitating the description and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be considered as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

The embodiment of the application provides a carbon dioxide purification device.

Referring to fig. 1, in an embodiment, the carbon dioxide purifying apparatus includes a rectifying tower 100, a first feeding and discharging assembly, and a condenser 200. The inner cavity of the rectifying tower 100 comprises a rectifying section 110 and a stripping section 120 which are distributed along the axial direction, and the rectifying section 110 is positioned above the stripping section 120; the first feeding and discharging assembly comprises a first feeding pipe 310, a first discharging pipe 320 and a return pipe 330, wherein the first discharging pipe 320 is connected with the top of the rectifying tower 100; taking the position of the connection part of the first feeding pipe 310 and the rectifying tower 100 as A, the central line of the rectifying tower 100 along the axial direction as B, the bottom position of the rectifying tower 100 as C, wherein A is positioned between the rectifying section 110 and the stripping section 120, and the distance between A and B is smaller than the distance between A and C; one end of the condenser 200 is connected to one end of the first discharging pipe 320 far away from the rectifying tower 100, the other end of the condenser 200 is connected to the rectifying tower 100 through the return pipe 330, and the connection between the return pipe 330 and the rectifying tower 100 is located between the rectifying section 110 and the connection between the first discharging pipe 320 and the rectifying tower 100.

Based on the structural design, in the embodiment, after the raw material enters the rectifying tower 100 from the first feeding pipe 310, the gaseous component containing impurities in the raw material rises upwards and passes through the rectifying section 110, and then comes out from the top of the rectifying tower 100 and enters the condenser 200 through the first discharging pipe 320; then, in the condenser 200, the top distillate of the tower, in which the temperature of the gaseous component is reduced and converted into a liquid state, flows out from the end of the condenser 200 away from the first discharge pipe 320, and meanwhile, according to the difference of the thermal state of the raw material, a part of the liquid component flows back to the top of the rectifying tower 100 from the return pipe 330, and flows down through the rectifying section 110 from the top of the tower, in the process, the liquid component and the gas phase component rising up in the rectifying section 110 are contacted to complete the process of material separation, that is, impurities in the liquid can go up along with the gas, and useful components, that is, the substances to be purified, can go down along with the liquid, so that the purpose of purifying the carbon dioxide raw material can be achieved. In this application, because the junction a of first inlet pipe 310 and rectifying column 100 is located between rectifying section 110 and stripping section 120, and the distance between this junction a and rectifying column 100 central line B is little and the distance between a and rectifying column 100 bottom C, namely the junction of first inlet pipe 310 and rectifying column 100 should be located the well lower part of rectifying column 100, like this, just so, the height that just can guarantee rectifying section 110 is greater than the height of stripping section 120 far away, thereby increased from the contact path length of liquid that flows back in return pipe 330 in rectifying section 110 department and gaseous phase, and then can make the raw materials when different thermal states, all can obtain more effective separation and purification, and then improved this carbon dioxide purification device's purification efficiency.

Further, referring to fig. 1, in the present embodiment, the carbon dioxide purifying apparatus further includes a reboiler 400 and a second feeding and discharging component; the reboiler 400 is arranged in the inner cavity of the rectifying tower 100, and is located below the stripping section 120, the second feeding and discharging component comprises a second feeding pipe 510, a second heating pipe and a second discharging pipe 530 which are connected in sequence, the second heating pipe is arranged in the reboiler 400, one end of the second feeding pipe 510 extends into the rectifying tower 100 and then is connected with the second heating pipe, one end of the second discharging pipe 530 is connected with one end of the second heating pipe far away from the second feeding pipe 510, and the other end of the second discharging pipe 530 extends out of the rectifying tower 100 and then is connected with the first feeding pipe 310. Specifically, the reboiler 400 is located below the stripping section 120, the junction of the second feed pipe 510 and the shell of the rectifying column 100 is located between the stripping section 120 and the reboiler 400, the junction of the second feed pipe 530 and the shell of the rectifying column 100 is located between the reboiler 400 and the bottom of the rectifying column 100, of course, in other embodiments, the positions of the second feeding pipe 510 and the second discharging pipe 530 entering and exiting from the shell of the rectifying tower 100 can be set according to actual requirements, but in this embodiment, the pipeline design can make the pipeline structure design simpler, also, the second discharge pipe 530 is located below the first feed pipe 310, so that the liquid feedstock can be selectively introduced into the reboiler 400 from the second feed pipe 510, and then the gas raw material is heated by the reboiler 400 and then converted into a gaseous raw material, and the gaseous raw material passes through the second discharging pipe 530 and conveniently ascends to be conveyed into the first feeding pipe 310, so that the purification process for separating impurities is continuously completed. It can be understood that, because the first feeding and discharging component and the second feeding and discharging component are simultaneously arranged in this embodiment, when the raw material is in different thermal states, the raw material can enter the corresponding feeding and discharging component according to the specific thermal state, for example, when the raw material is in a gas state, the first feeding pipe 310 can be selected for feeding, and when the raw material is in a liquid state or a gas-liquid mixed state, the second feeding pipe 510 can be selected for feeding, and the raw material is heated by the reboiler 400 to be converted into the gas state and then enters the rectifying tower 100 through the first feeding pipe 310, and after being subdivided, the feeding position is changed, so that the feeding condition in the actual production can be adapted more, and higher purification efficiency can be obtained.

Further, as shown in fig. 1, in the present embodiment, the carbon dioxide purification apparatus further includes a third inlet and outlet assembly; the third feeding and discharging assembly comprises a third feeding pipe 610, a third heating pipe and a third discharging pipe 630 which are connected in sequence, the third heating pipe is arranged in the reboiler 400, one end of the third feeding pipe 610 extends into the rectifying tower 100 and then is connected with the third heating pipe, one end of the third discharging pipe 630 is connected with one end, far away from the third feeding pipe 610, of the third heating pipe, and the other end of the third discharging pipe 630 extends out of the rectifying tower 100 and then is connected with the condenser 200; the second heating pipe and the third heating pipe are independently provided from each other in the reboiler 400. Thus, the heating of two materials can be realized by using one rectifying tower 100, and the utilization rate of the carbon dioxide purifying device can be improved. However, the design is not limited to this, in other embodiments, a fourth feeding and discharging component or even more feeding and discharging components may be further provided, and each of the feeding and discharging components includes a corresponding feeding pipe, a corresponding heating pipe, a corresponding discharging pipe, and the like, so that heating and purification of various materials are realized.

Specifically, in the present embodiment, the condenser 200 has a first cooling pipe (not shown) and a second cooling pipe 710 that are independent of each other; one end of the first cooling pipe is connected to the first discharge pipe 320, and the other end of the first cooling pipe is connected to the return pipe 330; the inlet end of the second cooling line 710 is connected to a third tapping pipe 630. Thus, the second material is heated and evaporated by the reboiler 400 to remove impurities, and then is transported to the condenser 200 through the third discharging pipe 630 to be cooled and converted into a purified liquid, and finally is output through the outlet end of the second cooling pipe 710 of the condenser 200.

In this embodiment, for better realization to the liquid control in the return pipe 330, as shown in fig. 1, the return pipe 330 is provided with a return regulating valve set, and the return ratio can be better adjusted in time through the return regulating valve set, thereby being beneficial to further improving the purification efficiency of the carbon dioxide purification device. Specifically, in the present embodiment, the backflow regulating valve group includes a first regulating valve 810, a second regulating valve 820, and a third regulating valve 830, and the first regulating valve 810, the second regulating valve 820, and the third regulating valve 830 are sequentially arranged in a pipeline direction from the condenser 200 to the rectifying tower 100 along the backflow pipe 330. So, through the combination of a plurality of governing valves, just can realize the quick accurate regulation and control to the reflux ratio.

Further, referring to fig. 1, in the present embodiment, the first feeding and discharging assembly further includes a return branch pipe 331, and the connection positions of the two ends of the return branch pipe 331 and the return pipe 330 are respectively located between the first regulating valve 810 and the condenser 200, and between the third regulating valve 830 and the rectifying tower 100; the backflow regulating valve group further comprises a fourth regulating valve 840, and the fourth regulating valve 840 is arranged on the backflow branch pipe 331. In this case, the return manifold 331 mainly serves as a backup, i.e., when the set of return regulating valves on the return pipe 330 fails, the return manifold 331 is opened to allow flow through by opening the fourth regulating valve 840.

It should be noted that, in the present application, the carbon dioxide purification apparatus has other components, such as a column bottom thermometer 910, a column bottom level gauge 920, a gas pressure valve 930, a column bottom residual liquid outlet 940, and the like, in addition to the aforementioned component structures. In the inner cavity of the rectifying tower 100, a plurality of layers of trays are filled at the rectifying section 110 and the stripping section 120, and the trays are usually provided with a plurality of through holes, so that two fluids can be in close contact with each other to perform mass exchange between two phases, thereby achieving the purpose of separating components of a liquid mixture or a gas mixture. In addition, a column bottom thermometer 910 is communicated with the bottom of the rectifying column 100 to test the liquid temperature at the bottom of the rectifying column 100; a tower bottom residual liquid outlet pipe 940 is connected to the bottom end of the tower bottom of the rectifying tower 100 so as to conveniently discharge residual liquid at the bottom of the tower bottom; the tower bottom liquid level meter 920 is externally arranged on the shell of the rectifying tower 100, but is positioned below the stripping section 120 and is mainly used for monitoring the liquid level condition of liquid in a cavity below the stripping section 120; the gas pressure valve 930 is disposed at the top of the rectifying column 100 and is used for monitoring and adjusting the gas pressure state at the top of the column.

Referring to fig. 1 and fig. 2, the present application further provides a feeding method of a purification apparatus, the feeding method of the purification apparatus is completed by using the carbon dioxide purification apparatus as described above, the specific structure of the carbon dioxide purification apparatus refers to the above embodiments, and the feeding method of the purification apparatus adopts all technical solutions of all the above embodiments, so that all the beneficial effects brought by the technical solutions of the above embodiments are also achieved, and are not repeated herein. The carbon dioxide purification apparatus comprises a first feed pipe 310 for gaseous feed and a second feed pipe 510 for liquid feed, the purification apparatus feed method comprising the steps of:

s1, obtaining a feeding thermal state parameter q of the raw material entering the rectifying tower 100, and dividing the raw material entering the rectifying tower 100 into a cold liquid feeding state where q is greater than 1, a saturated liquid feeding state where q is 1, a gas-liquid mixture feeding state where q is greater than 0 and less than 1, a saturated steam feeding state where q is 0, and a superheated steam feeding state where q is less than 0 according to a q value;

specifically, in the cold liquid feed state where q > 1, the actual temperature of the feedstock is greater than its bubble point temperature; at the saturated liquid feed state where q is 1, the actual temperature of the feedstock is equal to its bubble point temperature; in the gas-liquid mixture feeding state with q being more than 0 and less than 1, the actual temperature of the raw material is more than the bubble point temperature but less than the dew point temperature; at a saturated steam feed condition where q is 0, the actual temperature of the feedstock is equal to its dew point temperature; at the superheated steam feed condition with q < 0, the actual temperature of the feedstock is greater than its dew point temperature.

S2, when the liquid is in a cold liquid feeding state, a saturated liquid feeding state and a gas-liquid mixture feeding state, the raw material enters the reboiler 400 at the bottom of the rectifying tower 100 from the second feeding pipe 510, is converted into a gas state after being heated and then enters the first feeding pipe 310; in the saturated steam feeding state and the superheated steam feeding state, the raw material enters the rectifying tower 100 from the first feeding pipe 310;

s3, adjusting the reflux ratio R of the reflux pipe 330 according to the q value.

In the application, because a plurality of feeding positions such as the first feeding pipe 310 and the second feeding pipe 510 are arranged on the carbon dioxide purification device, and before feeding, the feeding state of the raw material can be specifically determined according to the feeding thermal state parameter q of the raw material, so that a proper feeding position is selected, and meanwhile, the reflux ratio R on the reflux pipe 330 can be adjusted according to the q value, so that the actual feeding condition is adapted more, and higher purification efficiency is obtained.

Further, in the present embodiment, in step S1, the feeding needs to satisfy the following feeding conditions:

y＝﹛q/(q-1)﹜x-﹛1/(q-1)﹜xF

wherein q ═ L' -L)/F; x is the mole fraction of the raw material; f is the flow rate of the raw material; l is the mass flow rate of the vapor substance descending from each tray in the rectifying section 110 in the rectifying tower 100, and the unit is kmol/h; l' is the mass flow rate of vapor species descending per tray in stripping section 120 in rectification column 100 in kmol/h.

Specifically, q is 1kmol of heat required for the feed to become saturated steam per kmole of latent heat of vaporization of the feedstock. The above-mentioned feeding conditions are the q-line equation of the feeding. The operating line equation of the rectifying section 110 is (L/V) x + (D/V) xD; the operating line equation of the stripping section 120 is (L '/V ') x- (W/V ') xW; wherein D is the amount of overhead distillate and the unit is kmol/h; w is the residual liquid amount of the tower kettle, and the unit is kmol/h; v is the mass flow rate of the vapor substance ascending from each tray in the rectifying section 110, and the unit is kmol/h; v' is the mass flow rate of the vapor material ascending from each tray in the stripping section 120, and the unit is kmol/h; xF is the mole fraction of volatile components in the raw materials; xW: the mole fraction of volatile components in the residue at the bottom of the kettle; xD: mole fraction of volatile components in the overhead distillate. For the feed equation, the trajectory must satisfy both the operating line equation of the rectifying section 110 and the operating line equation of the stripping section 120, so that the q-line equation can be obtained by substituting the two operating line equations into q ═ L' -L/F.

It will be appreciated that, according to the above formula, the q-line equation should be a straight line equation with the feed thermal state parameter q and feed composition xF determined. When the feed conditions such as xF and q are changed, the composition of the distillate and the bottoms is inevitably changed, and in this case, in order to obtain a better purification efficiency, the feed position is appropriately changed and the reflux ratio R is adjusted in time, and these changes can be achieved by the carbon dioxide purification apparatus and the feed method of the purification apparatus described above. In particular, in this embodiment, the raw material is preferably fed into the rectifying tower 100 in a saturated steam feeding state, so that the feeding manner is more economical and common.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A carbon dioxide purification apparatus, comprising:

2. The carbon dioxide purification apparatus of claim 1, further comprising a reboiler and a second feed and discharge assembly;

3. The carbon dioxide purification apparatus of claim 2, further comprising a third feed assembly; the third feeding and discharging assembly comprises a third feeding pipe, a third heating pipe and a third discharging pipe which are connected in sequence, the third heating pipe is arranged in the reboiler, one end of the third feeding pipe extends into the rectifying tower and then is connected with the third heating pipe, one end of the third discharging pipe is connected with one end, far away from the third feeding pipe, of the third heating pipe, and the other end of the third discharging pipe extends out of the rectifying tower and then is connected with the condenser;

4. The carbon dioxide purification apparatus according to claim 3, wherein the condenser has a first cooling pipe and a second cooling pipe which are independent from each other; one end of the first cooling pipeline is connected with the first discharge pipe, and the other end of the first cooling pipeline is connected with the return pipe; the inlet end of the second cooling pipeline is connected with the third discharge pipe.

5. The carbon dioxide purifying apparatus as claimed in any one of claims 1 to 4, wherein a return flow regulating valve set is provided on the return pipe.

6. The carbon dioxide purification apparatus of claim 5, wherein the set of reflux modulation valves includes a first modulation valve, a second modulation valve, and a third modulation valve, and the first modulation valve, the second modulation valve, and the third modulation valve are arranged in sequence in a direction of a pipe from the condenser to the rectifying tower along the reflux pipe.

7. The carbon dioxide purification device of claim 6, wherein the first feeding and discharging assembly further comprises a return branch pipe, and the connection between the two ends of the return branch pipe and the return pipe is respectively located between the first regulating valve and the condenser, and between the third regulating valve and the rectifying tower; the backflow regulating valve group further comprises a fourth regulating valve, and the fourth regulating valve is arranged on the backflow branch pipe.

8. A purification plant feeding method, characterized in that it is carried out using a carbon dioxide purification plant according to any one of claims 1 to 7, comprising a first feeding pipe for gaseous feeding and a second feeding pipe for liquid feeding, comprising the steps of:

s3, adjusting the reflux ratio R on the reflux pipe according to the q value.

9. The method of feeding purification apparatus as claimed in claim 8, wherein in step S2, the feeding material satisfies the following feeding conditions:

y＝﹛q/(q-1)﹜x-﹛1/(q-1)﹜xF

10. The purification apparatus feed method of claim 9, wherein the feedstock enters the rectification column in the saturated vapor feed state.