CN219424048U - Activated carbon adsorption device and energy utilization system for polysilicon tail gas treatment thereof - Google Patents

Abstract

The application relates to an active carbon adsorption device, the inner chamber has been seted up to the casing, the air inlet pipeline stretches into in the inner chamber at least partially, a plurality of active carbon adsorption posts set up in the inner chamber, a plurality of active carbon adsorption posts set up with the central axis equipartition of absorption air inlet pipeline, the one end of arbitrary one of a plurality of active carbon adsorption posts is provided with first pipeline, a plurality of first pipelines all communicate with the one end of absorption air inlet pipeline, desorption air inlet pipeline stretches into in the inner chamber at least partially, the other end of arbitrary one of a plurality of active carbon adsorption posts is provided with the second pipeline, a plurality of second pipelines all communicate with the one end of desorption air inlet pipeline. Above-mentioned scheme can solve multiunit series connection active carbon adsorption column and exist and be close to the absorptive impurity of production tail gas active carbon adsorption column many, sweeps multiunit series connection active carbon adsorption column step by step through the hydrogen is reverse, and the dynamics that is sweeping to being close to production tail gas active carbon adsorption column diminishes and leads to regeneration effect not good to lead to the cyclic utilization effect of active carbon adsorption column not good.

Description

Activated carbon adsorption device and energy utilization system for polysilicon tail gas treatment thereof

Technical Field

The application relates to the technical field of polysilicon tail gas recovery, in particular to an activated carbon adsorption device and an energy utilization system for polysilicon tail gas treatment of the activated carbon adsorption device.

Background

The process of producing polysilicon by reducing trichlorosilane by adopting the Siemens method is improved, the reaction conversion rate is about 10 percent, unreacted hydrogen, trichlorosilane and reaction byproducts silicon tetrachloride and hydrogen chloride form production tail gas together, and the tail gas is separated and recovered by a dry recovery system. The traditional dry recovery system consists of three parts of condensing and separating chlorosilane, absorbing and desorbing and separating hydrogen chloride, absorbing and purifying and recovering hydrogen. The method comprises the steps of pressurizing and condensing production tail gas to recover liquid chlorosilane, separating and recovering most of hydrogen chloride in noncondensable gas in a low-temperature chlorosilane absorption-high-temperature desorption mode, adsorbing a very small amount of chlorosilane, hydrogen chloride and other impurities by activated carbon, returning most of the recovered hydrogen after adsorption to a silicon tetrachloride hydrogenation system, desorbing the chlorosilane and the hydrogen chloride adsorbed by the activated carbon by using a small amount of recovered hydrogen as reverse blowing gas, returning the desorbed mixed gas to a condensation process of a dry recovery system, and delivering the separated hydrogen chloride to the silicon tetrachloride hydrogenation system to participate in reaction.

In the process of the polysilicon dry recovery technology, the purification and purification of the hydrogen in the production tail gas by adopting an active carbon adsorption column is the main stream treatment method for recycling the hydrogen in the improved Siemens at present. The active carbon adsorption column is key equipment of the process method, and the equipment performance and the processing capacity directly determine the cost of hydrogen recovery. When the activated carbon adsorption column works, three processes are divided: the active carbon is used for carrying out adsorption purification on hydrogen, heating the active carbon to desorb impurity gas, and reversely purging and cooling the active carbon by the hydrogen to enable the active carbon to work continuously. The latter two processes are combined into the regeneration process of the activated carbon.

In the related art, in order to promote the purity to hydrogen in the tail gas, the activated carbon adsorption column is through setting up the hydrogen that the multiunit established ties set up to production tail gas and adsorb the purification to promote the adsorption rate of activated carbon adsorption chlorosilane, hydrogen chloride and other impurity, thereby lead to being close to production tail gas activated carbon adsorption column absorptive impurity more, and purge, the cooling makes activated carbon continue work to multiunit established ties activated carbon adsorption column through hydrogen is reverse, along with the dynamics of reverse purge diminish, be close to production tail gas activated carbon adsorption column can't obtain effectual regeneration, thereby lead to the cyclic utilization effect of activated carbon adsorption column not good.

Disclosure of Invention

Based on this, there are many adjacent production tail gas active carbon adsorption column absorbing impurity to the multiunit active carbon adsorption column in the prior art to necessary, and purge multiunit active carbon adsorption column through hydrogen reverse, and the cooling makes the active carbon continue to work, along with the dynamics of reverse purge diminish, adjacent production tail gas active carbon adsorption column can't obtain effectual regeneration to lead to the adsorption effect of active carbon adsorption column not good. The energy utilization system for the active carbon adsorption device and the polysilicon tail gas treatment thereof is provided, so that the maximum utilization of multiple groups of active carbon adsorption columns is ensured, and the better regeneration effect of the hydrogen to the reverse purging of the multiple groups of active carbon adsorption columns is ensured, so that the cyclic utilization effect of the active carbon adsorption columns is ensured.

The utility model provides an active carbon adsorption device, includes casing, absorption admission line, a plurality of active carbon adsorption column and desorption admission line, the inner chamber has been seted up to the casing, the admission line is at least partly stretched into in the inner chamber, a plurality of active carbon adsorption column set up in the inner chamber, a plurality of active carbon adsorption column with the central axis equipartition of absorption admission line sets up, the one end of arbitrary one of a plurality of active carbon adsorption column is provided with first pipeline, a plurality of first pipelines all with the one end intercommunication of absorption admission line, desorption admission line at least part stretches into in the inner chamber, absorption admission line with the desorption admission line is relative, just the absorption admission line with the central axis of desorption admission line is unanimous, the other end of arbitrary one of a plurality of active carbon adsorption columns is provided with the second pipeline, a plurality of second pipelines all with the one end intercommunication of desorption admission line.

Based on the active carbon adsorption device, the application still provides an energy utilization system of polycrystalline silicon tail gas treatment, including above active carbon adsorption device, absorption tower, analytic tower, first heat exchanger, second heat exchanger and third heat exchanger, active carbon adsorption device's absorption gas outlet line is connected with the hydrogen storage tank, the hydrogen storage tank with the tube side import of first heat exchanger links to each other, the tube side export of first heat exchanger is linked together with desorption admission line, active carbon adsorption device's desorption gas outlet line with the shell side import of first heat exchanger links to each other, the shell side export of first heat exchanger with the shell side import of second heat exchanger links to each other, the shell side export of second heat exchanger with the shell side import of third heat exchanger, the gas phase export of third heat exchanger with the waste gas import of absorption tower links to each other, the rich liquor export of absorption tower with the tube side import of third heat exchanger links to each other, the export of third heat exchanger with the second heat exchanger's the export of liquid phase is linked to each other with the second heat exchanger's shell side import, the rich liquor import of third heat exchanger all links to each other with the inlet of third heat exchanger.

Preferably, in the energy utilization system for treating polycrystalline silicon tail gas, the energy utilization system further comprises a fourth heat exchanger, wherein the tube side outlets of the second heat exchanger and the third heat exchanger are both communicated with the tube side inlet of the fourth heat exchanger, the tube side outlet of the fourth heat exchanger is connected with the rich liquid inlet of the analysis tower, the lean liquid outlet of the analysis tower is connected with the shell side inlet of the fourth heat exchanger, and the shell side outlet of the fourth heat exchanger is communicated with the lean liquid inlet of the absorption tower.

Preferably, in the energy utilization system for polysilicon tail gas treatment, the energy utilization system further comprises a fifth heat exchanger, wherein a tube side outlet of the third heat exchanger is connected with a tube side inlet of the fifth heat exchanger, a tube side outlet of the fifth heat exchanger is connected with a tube side inlet of the fourth heat exchanger, a shell side outlet of the fourth heat exchanger is connected with a shell side inlet of the fifth heat exchanger, and a shell side outlet of the fifth heat exchanger is connected with a lean solution inlet of the absorption tower.

Preferably, in the energy utilization system for treating polycrystalline silicon tail gas, a chlorosilane recovery pipeline is connected to a tube side outlet of the fifth heat exchanger, or a chlorosilane recovery pipeline is connected to a tube side inlet of the fifth heat exchanger.

Preferably, in the energy utilization system for treating polycrystalline silicon tail gas, the energy utilization system further comprises a first heater, wherein a tube side outlet of the first heat exchanger is connected with a heating inlet of the first heater, and a heating outlet of the first heater is connected with a desorption inlet of the activated carbon adsorption column.

Preferably, in the energy utilization system for treating polycrystalline silicon tail gas, the energy utilization system further comprises a polycrystalline silicon reduction furnace and a cooling heat exchange system, wherein a tail gas outlet of the polycrystalline silicon reduction furnace is connected with a tail gas inlet of the cooling heat exchange system, a gas phase outlet of the cooling heat exchange system is connected with an exhaust gas inlet of the absorption tower, a liquid phase outlet of the cooling heat exchange system is connected with a tube side inlet of the second heat exchanger, a cold hydrogen outlet of the absorption tower is connected with a refrigerant inlet of the cooling heat exchange system, and a refrigerant outlet of the cooling heat exchange system is connected with an adsorption inlet of the activated carbon adsorption column.

Preferably, in the energy utilization system for treating the polysilicon tail gas, the energy utilization system further comprises a silicon powder dust removing device, wherein a tail gas outlet of the polysilicon reduction furnace is connected with an inlet of the silicon powder dust removing device, and an outlet of the silicon powder dust removing device is connected with a tail gas inlet of the cooling heat exchange system.

The technical scheme that this application adopted can reach following beneficial effect:

in the activated carbon adsorption device disclosed by the embodiment of the application, the shell is provided with the inner cavity, the adsorption air inlet pipeline at least partially stretches into the inner cavity, the plurality of activated carbon adsorption columns are arranged in the inner cavity, the plurality of activated carbon adsorption columns are uniformly distributed and arranged on the central axis of the air inlet pipeline, one end of any one of the plurality of activated carbon adsorption columns is provided with the first pipeline, and the plurality of first pipelines are communicated with one end of the adsorption air inlet pipeline, so that the flow of tail gas can be evenly distributed to the plurality of first pipelines in the adsorption process of the activated carbon adsorption device, and the plurality of activated carbon adsorption columns can achieve better adsorption effect; the desorption air inlet pipeline stretches into the inner chamber at least partially, and the absorption air inlet pipeline is relative with the desorption air inlet pipeline, and adsorb the air inlet pipeline with the central axis of desorption air inlet pipeline is unanimous, and the other end of arbitrary one of a plurality of active carbon adsorption posts is provided with the second pipeline, and a plurality of second pipelines all communicate with the one end of desorption air inlet pipeline to the flow of the hydrogen after making preheating can evenly distribute a plurality of second pipelines, thereby make a plurality of active carbon adsorption posts homoenergetic realize better regeneration effect, and then guarantee active carbon adsorption device's cyclic utilization effect.

Drawings

FIG. 1 is a front view showing a part of the structure of an activated carbon adsorption apparatus disclosed in an embodiment of the present application;

FIG. 2 is a cross-sectional view of an activated carbon adsorption apparatus disclosed in an embodiment of the present application;

fig. 3 is a schematic diagram of an energy utilization system for polysilicon tail gas treatment according to an embodiment of the present application.

Wherein: the device comprises a hydrogen storage tank 110, a hydrogen recovery pipeline 120, a shell 130, an air inlet pipeline 140, an activated carbon adsorption column 150, a desorption air inlet pipeline 160, an absorption tower 200, a desorption tower 300, a first heat exchanger 410, a second heat exchanger 420, a third heat exchanger 430, a fourth heat exchanger 440, a fifth heat exchanger 450, a first heater 460, a chlorosilane recovery pipeline 500, a reduction furnace 600, a cooling heat exchange system 700 and a silicon powder dust removal device 800.

Description of the embodiments

In order to facilitate an understanding of the present application, a more complete description of the present application will now be provided with reference to the relevant figures. Preferred embodiments of the present application are shown in the accompanying drawings. This application may, however, be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," "top," "bottom," "top," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

Referring to fig. 1 and 2, an activated carbon adsorption apparatus is disclosed in an embodiment of the present application, and the disclosed activated carbon adsorption apparatus includes a housing 130, an adsorption inlet pipe 140, a plurality of activated carbon adsorption columns 150, and a desorption inlet pipe 160.

The casing 130 can provide the installation basis for adsorbing inlet gas pipeline 140, a plurality of active carbon adsorption column 150 and desorption inlet gas pipeline 160, specifically, the inner chamber has been seted up to casing 130, adsorb inlet gas pipeline 140 at least part and stretch into in the inner chamber, a plurality of active carbon adsorption column 150 set up with the central axis equipartition of inlet gas pipeline 140, the one end of any one of a plurality of active carbon adsorption column 150 is provided with first pipeline, a plurality of first pipelines all communicate with the one end of adsorbing inlet gas pipeline 140, desorption inlet gas pipeline 160 at least part stretches into in the inner chamber, adsorption inlet gas pipeline 140 is relative with desorption inlet gas pipeline 160, the other end of any one of a plurality of active carbon adsorption column 150 is provided with the second pipeline, a plurality of second pipelines all communicate with the one end of desorption inlet gas pipeline 160.

In the adsorption process of the activated carbon adsorption device, the tail gas flows to the corresponding activated carbon adsorption columns 150 along the first pipelines through the adsorption air inlet pipeline 140, and as the first pipeline is arranged at one end of any one of the activated carbon adsorption columns 150, the inner diameters and the lengths of the first pipelines are identical, and the flow of the tail gas can be evenly distributed to the first pipelines, so that the activated carbon adsorption columns 150 can achieve better adsorption effect; in the regeneration process of the activated carbon adsorption device, the preheated hydrogen flows to the corresponding activated carbon adsorption columns 150 along the second pipelines through the desorption air inlet pipeline 160 respectively to be reversely purged, and as the second pipeline is arranged at the other end of any one of the activated carbon adsorption columns 150, the inner diameters and the lengths of the second pipelines are equal, the flow of the preheated hydrogen can be evenly distributed to the second pipelines, so that the activated carbon adsorption columns 150 can achieve better regeneration effect.

In the activated carbon adsorption apparatus disclosed in the embodiment of the present application, the housing 130 is provided with an inner cavity, the adsorption air inlet pipeline 140 at least partially extends into the inner cavity, the plurality of activated carbon adsorption columns 150 are disposed in the inner cavity, the plurality of activated carbon adsorption columns 150 are uniformly disposed with central axes of the air inlet pipeline 140, one end of any one of the plurality of activated carbon adsorption columns 150 is provided with a first pipeline, and the plurality of first pipelines are all communicated with one end of the adsorption air inlet pipeline 140, so that in an adsorption process of the activated carbon adsorption apparatus, the flow of tail gas can be evenly distributed to the plurality of first pipelines, thereby enabling the plurality of activated carbon adsorption columns 150 to achieve better adsorption effects; the desorption air inlet pipeline 160 stretches into the inner cavity at least partially, the adsorption air inlet pipeline 140 is opposite to the desorption air inlet pipeline 160, the adsorption air inlet pipeline 140 is consistent with the central axis of the desorption air inlet pipeline 160, the other end of any one of the plurality of activated carbon adsorption columns 150 is provided with a second pipeline, and the plurality of second pipelines are communicated with one end of the desorption air inlet pipeline 160, so that the flow of preheated hydrogen can be evenly distributed to the plurality of second pipelines, the plurality of activated carbon adsorption columns 150 can achieve better regeneration effect, and the recycling effect of the activated carbon adsorption device is guaranteed.

Referring to fig. 3, based on the above-mentioned activated carbon adsorption device, the present application further discloses an energy utilization system for treating polysilicon tail gas, where the disclosed energy utilization system for treating polysilicon tail gas includes the above-mentioned activated carbon adsorption device, absorption tower 200, desorption tower 300, first heat exchanger 410, second heat exchanger 420 and third heat exchanger 430, and the above-mentioned activated carbon adsorption device, absorption tower 200, desorption tower 300, first heat exchanger 410, second heat exchanger 420 and third heat exchanger 430 are described in the following:

the adsorption gas outlet pipeline of the active carbon adsorption device is connected with a hydrogen storage tank 110 so as to store the high-purity hydrogen adsorbed and purified by the active carbon adsorption device into the hydrogen storage tank 110, the temperature of the purified high-purity hydrogen is lower, about-10 ℃, the purified high-purity hydrogen is required to be heated to 182 ℃ and then is introduced into the active carbon adsorption device for reverse purging, and after the active carbon adsorption device is reversely purged by the hydrogen at 182 ℃, the temperature of the hydrogen is reduced to 164 ℃, and the temperature of the part of the hydrogen is higher. The desorption outlet pipeline of the activated carbon adsorption device is connected with the shell side inlet of the first heat exchanger 410 so as to introduce the purged hydrogen with the temperature of 164 ℃ into the shell side of the first heat exchanger 410, the hydrogen storage tank 110 is connected with the tube side inlet of the first heat exchanger 410 so as to introduce the hydrogen with the temperature of-10 ℃ into the tube side of the first heat exchanger 410 first and exchange heat with the hydrogen with the temperature of 164 ℃ in the shell side, thereby recycling the heat in the hydrogen with the temperature of 164 ℃ to preheat the hydrogen with the temperature of-10 ℃ and avoiding the heat waste in the hydrogen with the temperature of 164 ℃, and the tube side outlet of the first heat exchanger 410 is communicated with the desorption inlet pipeline 160 of the activated carbon adsorption device so as to reversely purge the preheated hydrogen into the activated carbon adsorption device and realize the desorption regeneration of the activated carbon adsorption device.

In the first heat exchanger 410, the hydrogen at 164 ℃ exchanges heat and preheats the hydrogen at-10 ℃, the temperature of the hydrogen at 164 ℃ is reduced to about 92 ℃ after heat exchange, and as the hydrogen is the hydrogen after the active carbon adsorption device is purged, impurities such as hydrogen chloride are carried in the hydrogen after the purging, chlorine needs to be recycled, and as the temperature of the hydrogen after the purging is higher, heat is carried, and cooling is required before recycling. The shell side outlet of the first heat exchanger 410 is connected with the shell side inlet of the second heat exchanger 420, so that 92 ℃ hydrogen is introduced into the shell side of the second heat exchanger 420 for heat exchange pre-cooling, heat in 92 ℃ hydrogen is recovered through the second heat exchanger 420, and the cooling effect is achieved.

The shell side outlet of the second heat exchanger 420 is connected with the shell side inlet of the third heat exchanger 430, so that pre-cooled hydrogen (the hydrogen carries impurities such as hydrogen chloride) is introduced into the shell side of the third heat exchanger 430 for cooling, the rich liquid outlet of the absorption tower 200 is connected with the tube side inlet of the third heat exchanger 430, and in the absorption tower 200, the tower top temperature is about-65 ℃, the tower bottom temperature is about-58 ℃, namely, the temperature of recovered hydrogen is about-65 ℃, the temperature of chlorosilane lean liquid required to be introduced into the absorption tower 200 is about-58 ℃, the temperature of chlorosilane rich liquid after hydrogen chloride in the waste gas is required to be absorbed is about-58 ℃, so that the chlorosilane rich liquid at-58 ℃ is introduced into the shell side of the third heat exchanger 430, the pre-cooled hydrogen is cooled, and the pre-cooled hydrogen is separated into the chlorosilane rich liquid (a small amount of hydrogen chloride in the liquid) and gaseous waste gas (mainly hydrogen chloride and hydrogen). The pre-cooled hydrogen is directly cooled by utilizing the cold energy in the low-temperature chlorosilane rich liquid discharged by the absorption tower 200, so that the additional cold energy is avoided to cool the hydrogen, the consumption of the cold energy is reduced, and the cold energy in the low-temperature chlorosilane rich liquid discharged by the absorption tower 200 is fully recycled.

The liquid phase outlet of the third heat exchanger 430 is connected with the tube side inlet of the second heat exchanger 420, so that the chlorosilane rich liquid obtained by gas-liquid separation in the third heat exchanger 430 is introduced into the tube side of the second heat exchanger 420, heat exchange is performed with 92 ℃ hydrogen in the shell side of the second heat exchanger 420, the chlorosilane rich liquid is preheated by the 92 ℃ hydrogen, heat in the 92 ℃ hydrogen is recycled, heat waste in the 92 ℃ hydrogen is avoided, and the second heat exchanger 420 plays a role in preheating the chlorosilane rich liquid and also plays a role in recycling heat in the 92 ℃ hydrogen. The tube side outlet of the second heat exchanger 420 is communicated with the rich liquid inlet of the analysis tower 300, so that the preheated chlorosilane rich liquid is introduced into the analysis tower 300 for analysis, hydrogen chloride in the chlorosilane rich liquid is analyzed, and the hydrogen chloride is recovered through the top of the analysis tower 300. Meanwhile, the outlet of the tube side of the third heat exchanger 430 is communicated with the rich solution inlet of the resolving tower 300, so that the chlorosilane rich solution which is introduced into the tube side of the third heat exchanger 430 from the rich solution outlet of the absorption tower 200 is introduced into the resolving tower 300 for resolving, the temperature of the tower bottom is about 110 ℃, the temperature of the tower top is about 60 ℃, namely the temperature of the recovered hydrogen chloride gas is about 60 ℃, the temperature of the chlorosilane rich solution which is required to be introduced into the resolving tower 300 is about 110 ℃, and the temperature of the resolved chlorosilane lean solution is about 110 ℃. Since the chlorosilane rich liquid exchanges heat in the third heat exchanger 430 and can also have a preheating effect on the chlorosilane rich liquid, the chlorosilane rich liquid is preheated through the pipe side outlet of the second heat exchanger 420 or the pipe side outlet of the third heat exchanger 430, so that the chlorosilane rich liquid can be heated to the operating temperature of the analysis tower 300 with little additional heat, and the heat consumption is reduced.

The gas phase outlet of the third heat exchanger 430 is connected with the exhaust gas inlet of the absorption tower 200, the temperature of the exhaust gas after two-stage cooling by the second heat exchanger 420 and the third heat exchanger 430 is about-58 ℃, the requirement of the high-pressure low-temperature working condition of the absorption tower 200 is met, the exhaust gas is directly connected into the absorption tower 200, hydrogen chloride in the exhaust gas is absorbed by spraying the chlorosilane lean solution, the hydrogen chloride in the exhaust gas is dissolved into the liquid-phase chlorosilane lean solution to obtain the chlorosilane rich solution, and hydrogen in the exhaust gas is recovered through the top of the absorption tower 200. Therefore, no external cold is introduced in the hydrogen cooling link at 164 ℃ after purging, and the consumption of cold in the recovery process can be greatly reduced.

In the energy utilization system of active carbon adsorption device and polycrystalline silicon tail gas treatment thereof disclosed by the embodiment of the application, firstly, heat in 164 ℃ hydrogen is used for preheating hydrogen at minus 10 ℃, heat in 164 ℃ hydrogen is recycled through the first heat exchanger 410, heat in 164 ℃ hydrogen is avoided being wasted, secondly, heat in 92 ℃ hydrogen is recycled through the second heat exchanger 420, chlorosilane rich liquor is preheated by 92 ℃ hydrogen, heat in 92 ℃ hydrogen is recycled, heat in 92 ℃ hydrogen is avoided being wasted, heat in 164 ℃ hydrogen is recycled through two stages, heat in 164 ℃ hydrogen is fully recycled, heat is avoided being wasted, heat consumption in the recycling process can be reduced, and recycling cost can be reduced. Meanwhile, the pre-cooled hydrogen is directly cooled by utilizing the cold energy in the low-temperature chlorosilane rich liquid discharged by the absorption tower 200, so that the additional cold energy is avoided to cool the hydrogen, the waste of the cold energy is avoided, the cold energy in the low-temperature chlorosilane rich liquid discharged by the absorption tower 200 is fully recycled, and the consumption of the cold energy is reduced, thereby reducing the recycling cost.

As described above, the temperature of the chlorosilane rich solution required to be introduced into the resolving tower 300 is about 110 ℃, even though the temperature of the chlorosilane rich solution cannot reach 110 ℃ after being preheated by the second heat exchanger 420 and the third heat exchanger 430, a small amount of additional heat is required to heat the preheated chlorosilane rich solution, and therefore, in an alternative embodiment, the energy cascade utilization system disclosed in the application may further include the fourth heat exchanger 440, the tube side outlets of the second heat exchanger 420 and the third heat exchanger 430 are all communicated with the tube side inlet of the fourth heat exchanger 440, the lean solution outlet of the resolving tower 300 is connected with the shell side inlet of the fourth heat exchanger 440, the temperature of the chlorosilane lean solution introduced into the shell side of the fourth heat exchanger 440 from the lean solution outlet of the resolving tower 300 is higher, the chlorosilane rich solution in the tube side of the fourth heat exchanger 440 can be further heated, the heat in the chlorosilane lean solution is recycled, the heat is avoided, and the recycling cost is reduced.

The tube side outlet of the fourth heat exchanger 440 is connected with the rich liquid inlet of the resolving tower 300 to introduce the heated chlorosilane rich liquid into the resolving tower 300 for resolving work, the shell side outlet of the fourth heat exchanger 440 is communicated with the lean liquid inlet of the absorbing tower 200 to exchange heat with the chlorosilane lean liquid discharged from the lean liquid outlet of the resolving tower 300 and then introduce the chlorosilane lean liquid into the absorbing tower 200, hydrogen chloride in the waste gas is sprayed and absorbed, and the hydrogen chloride in the waste gas is dissolved into the chlorosilane lean liquid to obtain the chlorosilane rich liquid.

In this application, after the chlorosilane rich solution discharged from the absorber 200 has a temperature of about-58 ℃ and a temperature of-58 ℃ and the chlorosilane rich solution is cooled in the third heat exchanger 430, more cold energy is still present in the chlorosilane rich solution, if the chlorosilane rich solution is directly introduced into the analyzing tower 300 to perform analysis, more heat is required to be consumed, meanwhile, after the chlorosilane lean solution discharged from the analyzing tower 300 has a temperature of about 110 ℃ and a temperature of 110 ℃ and the chlorosilane rich solution is heated in the fourth heat exchanger 440, more heat is still present in the chlorosilane lean solution, if the chlorosilane rich solution is directly introduced into the absorber 200 to perform analysis, more cold energy is required to be consumed, based on this, in an alternative embodiment, the energy cascade utilization system disclosed in this application may further comprise a fifth heat exchanger 450, a tube side outlet of the third heat exchanger 430 is connected with a tube side inlet of the fifth heat exchanger 450, the chlorosilane rich liquid after cooling the hydrogen in the third heat exchanger 430 is led into the tube side of the fifth heat exchanger 450, the shell side outlet of the fourth heat exchanger 440 is connected with the shell side inlet of the fifth heat exchanger 450, the chlorosilane lean liquid after heating the chlorosilane rich liquid in the fourth heat exchanger 440 is led into the shell side of the fifth heat exchanger 450, so that the chlorosilane lean liquid with higher temperature exchanges heat with the chlorosilane rich liquid with lower temperature in the fifth heat exchanger 450, the chlorosilane lean liquid and the chlorosilane rich liquid exchange heat sufficiently to heat the chlorosilane rich liquid, meanwhile, the chlorosilane lean liquid is cooled, the heat and the cold quantity carried by the chlorosilane rich liquid are fully recycled, the chlorosilane rich liquid with lower temperature can be heated to 110 ℃ after heat exchange, the operating temperature requirement of the analytical tower 300 can be met by only adding a small amount of heat, the consumption of heat in the tail gas recovery process is reduced, the heat in the high-temperature chlorosilane lean solution discharged from the analyzing tower 300 is fully recycled.

Meanwhile, the temperature of the chlorosilane lean solution with higher temperature is reduced after heat exchange, and the chlorosilane lean solution can be cooled to meet the working temperature requirement of the absorption tower 200 only by additionally adding a small amount of cooling capacity, so that the consumption of cooling capacity in the tail gas recovery process can be reduced, and the cooling capacity in the low-temperature chlorosilane rich solution discharged by the absorption tower 200 is fully recycled. Thereby avoiding heat waste in the liquid-phase chlorosilane lean solution with higher temperature and avoiding cold waste in the liquid-phase chlorosilane rich solution with lower temperature.

The tube side outlet of the fifth heat exchanger 450 is connected with the tube side inlet of the fourth heat exchanger 440, so that the chlorosilane rich liquid after heat exchange is introduced into the fourth heat exchanger 440 for further heating and then introduced into the analysis tower 300 for analysis. The shell side outlet of the fifth heat exchanger 450 is connected with the lean solution inlet of the absorption tower 200, so that the chlorosilane lean solution discharged from the lean solution outlet of the resolving tower 300 is introduced into the absorption tower 200 after two-stage heat exchange, hydrogen chloride in the waste gas is sprayed and absorbed, and the hydrogen chloride in the waste gas is dissolved into the chlorosilane lean solution to obtain the chlorosilane rich solution.

Preferably, the outlet of the tube side of the fifth heat exchanger 450 may be connected with a chlorosilane recovery pipeline 500, so that all the chlorosilane lean solution with higher temperature exchanges heat in the fifth heat exchanger 450, so that all the chlorosilane lean solution can heat the chlorosilane rich solution to higher temperature in the fifth heat exchanger 450, the additional heat required to be added is further reduced, the chlorosilane rich solution can be heated to the working temperature of the analytical tower 300 only by adding a smaller amount of additional heat, the additional heat required to be added is further reduced, the heat consumption in the tail gas recovery process is reduced, the environmental protection of the system is further improved, and the energy consumption and cost of tail gas recovery are reduced.

Of course, the pipe side inlet of the fifth heat exchanger 450 may be connected with a chlorosilane recovery pipe 500, so as to reduce the chlorosilane lean solution with higher temperature introduced into the fifth heat exchanger 450 for heat exchange by recovering a part of the chlorosilane lean solution with higher temperature, so that in the fifth heat exchanger 450, the chlorosilane rich solution with lower temperature can cool a smaller amount of chlorosilane lean solution to a lower temperature, and the chlorosilane lean solution can be cooled to the working temperature of the absorption tower 200 by adding a smaller amount of cooling capacity, thereby further reducing the cooling capacity required to be added additionally, reducing the consumption of cooling capacity in the tail gas recovery process, further improving the environmental protection of the system, and reducing the energy consumption and cost of tail gas recovery.

Because the temperature of the purge hydrogen required for desorption and regeneration of the activated carbon adsorption device is 182 ℃, in the first heat exchanger 410, 164 ℃ hydrogen cannot heat-10 ℃ hydrogen to 182 ℃, and additional heating hydrogen is required to be added to enable the temperature of the hydrogen to reach 182 ℃, and then the hydrogen is introduced into the activated carbon adsorption device for reverse purge. In an alternative embodiment, the energy cascade utilization system disclosed herein may further comprise a first heater 460, the tube side outlet of the first heat exchanger 410 being connected to the heating inlet of the first heater 460, the heating outlet of the first heater 460 being connected to the desorption inlet of the activated carbon adsorption unit. The first heat exchanger 410 can heat the hydrogen preheated in the first heat exchanger 410 to 182 ℃, then the hydrogen is introduced into the activated carbon adsorption device for reverse purging, and impurities such as hydrogen chloride adsorbed on the activated carbon adsorption device are blown away by the hydrogen in the process of reversely purging the activated carbon adsorption device, so that the activated carbon adsorption device is desorbed and regenerated, and the activated carbon adsorption device can be recycled.

Further, the number of the activated carbon adsorption devices may be at least three, and the at least three activated carbon adsorption devices are arranged in parallel, one or more of the at least three activated carbon adsorption devices is/are used for adsorbing purified hydrogen, one of the at least three activated carbon adsorption devices is used for desorption regeneration, one of the at least three activated carbon adsorption devices is used for standby, and the whole tail gas recovery process can be continuously and uninterruptedly performed. The hydrogen storage tank 110 is also connected with a hydrogen recovery pipeline 120, hydrogen is introduced into the reduction furnace 600 through the hydrogen recovery pipeline 120, and is used as a production raw material of the reduction furnace 600, so that hydrogen in tail gas is prevented from being wasted, and the environmental protection and energy conservation and resource recovery and conservation of the polysilicon production process are improved.

Preferably, the energy cascade utilization system disclosed in the present application may further include a polysilicon reduction furnace 600 and a cooling heat exchange system 700, wherein the temperature of the tail gas produced by the polysilicon reduction furnace 600 is about 220 ℃, and the main components thereof are as follows: the tail gas outlet of the polysilicon reduction furnace 600 is connected with the tail gas inlet of the cooling heat exchange system 700 to introduce the tail gas of the polysilicon reduction furnace 600 into the cooling heat exchange system 700 to cool the tail gas, and the tail gas is cooled to obtain a liquid-phase chlorosilane rich solution (a small amount of hydrogen chloride exists in the liquid) and gaseous waste gas (mainly hydrogen chloride and hydrogen). The gas phase outlet of the cooling heat exchange system 700 is connected with the exhaust gas inlet of the absorption tower 200, so that the exhaust gas is introduced into the absorption tower 200, the hydrogen chloride in the exhaust gas is sprayed and absorbed by the liquid-phase chlorosilane lean solution, the hydrogen chloride in the exhaust gas is dissolved into the chlorosilane lean solution, the hydrogen in the exhaust gas is recovered through the top of the absorption tower 200, the temperature of the top of the absorption tower 200 is about-65 ℃, the temperature of the bottom of the tower is about-58 ℃, namely the temperature of the recovered hydrogen is about-65 ℃, the temperature of the liquid-phase chlorosilane lean solution required to be introduced into the absorption tower 200 is about-65 ℃, and the temperature of the liquid-phase chlorosilane rich solution after the hydrogen chloride in the exhaust gas is absorbed is about-58 ℃. Because the temperature of the recovered hydrogen is about-65 ℃, the recovered low-temperature hydrogen can be used as the refrigerant of the cooling heat exchange system 700 to cool the tail gas, the cold hydrogen outlet of the absorption tower 200 is connected with the refrigerant inlet of the cooling heat exchange system 700, so that the recovered hydrogen is introduced into the cooling heat exchange system 700 to cool the tail gas, the temperature of the cooled waste gas is about-58 ℃, the recovered low-temperature hydrogen is directly used as the refrigerant of the cooling heat exchange system 700, the additional need of a cold source to cool the tail gas is avoided, and the cold quantity in the hydrogen is fully recycled.

The liquid phase outlet of the cooling heat exchange system 700 is connected with the tube side inlet of the second heat exchanger 420, so that the liquid phase chlorosilane rich liquid is introduced into the tube side of the second heat exchanger 420, heat exchange is performed with 92 ℃ hydrogen in the shell side of the second heat exchanger 420, the 92 ℃ hydrogen pre-heats the chlorosilane rich liquid, heat in the 92 ℃ hydrogen is recycled, heat waste in the 92 ℃ hydrogen is avoided, and the second heat exchanger 420 plays a role in preheating the chlorosilane rich liquid and also plays a role in recycling heat in the 92 ℃ hydrogen.

As described above, the cold hydrogen outlet of the absorption tower 200 is connected to the refrigerant inlet of the cooling heat exchange system 700, the temperature of the hydrogen after cooling the tail gas in the cooling heat exchange system 700 is about-15 ℃, and then the hydrogen is recovered and recycled, however, the impurities (hydrogen chloride) in the hydrogen recovered here are more, the purity of the hydrogen is lower, the hydrogen needs to be further purified, the refrigerant outlet of the cooling heat exchange system 700 is connected to the adsorption inlet of the activated carbon adsorption device, so that the hydrogen after heat exchange of the cooling heat exchange system 700 is introduced into the activated carbon adsorption device for adsorption purification, the high-purity hydrogen is recovered, and the working environment of the activated carbon adsorption device for adsorption purification is high pressure and low temperature, so that the hydrogen temperature after heat exchange of the cooling heat exchange system 700 is about-15 ℃ and just meets the working temperature of the adsorption purification of the activated carbon adsorption device, and the hydrogen after adsorption purification in the activated carbon adsorption device is recovered and stored by the hydrogen storage tank 110.

The tail gas of the polysilicon reduction furnace 600 contains silicon powder, the silicon powder is easier to block pipelines in subsequent systems, based on the silicon powder, in an alternative embodiment, the energy cascade utilization system disclosed in the application can further comprise a silicon powder dust removing device 800, a tail gas outlet of the polysilicon reduction furnace 600 is connected with an inlet of the silicon powder dust removing device 800, an outlet of the silicon powder dust removing device 800 is connected with a tail gas inlet of a cooling heat exchange system 700, so that high-temperature tail gas of the polysilicon reduction furnace 600 firstly passes through the silicon powder dust removing device 800 to recover silicon powder therein, and then the tail gas after the silicon powder is removed is introduced into the subsequent systems, thereby avoiding the silicon powder from blocking the pipelines in the subsequent systems, and improving the reliability and stability of the system. Specifically, the silicon dust collector 800 may be a bag-type dust collector.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples only represent a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the claims. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application is to be determined by the claims appended hereto.

Claims (8)

1. The utility model provides an active carbon adsorption device, its characterized in that, including casing, absorption admission line, a plurality of active carbon adsorption post and desorption admission line, the inner chamber has been seted up to the casing, the admission line at least partially stretches into in the inner chamber, a plurality of active carbon adsorption posts set up in the inner chamber, a plurality of active carbon adsorption posts with the central axis equipartition of absorption admission line sets up, the one end of any one of a plurality of active carbon adsorption posts is provided with first pipeline, a plurality of first pipelines all with the one end intercommunication of absorption admission line, desorption admission line at least part stretches into in the inner chamber, absorption admission line with desorption admission line is relative, just absorption admission line with the central axis of desorption admission line is unanimous, the other end of any one of a plurality of active carbon adsorption posts is provided with the second pipeline, a plurality of second pipelines all with the one end intercommunication of desorption admission line.

2. The energy utilization system for treating the polycrystalline silicon tail gas is characterized by comprising the active carbon adsorption device, an absorption tower, a desorption tower, a first heat exchanger, a second heat exchanger and a third heat exchanger according to claim 1, wherein an adsorption outlet pipeline of the active carbon adsorption device is connected with a hydrogen storage tank, the hydrogen storage tank is connected with a tube side inlet of the first heat exchanger, a tube side outlet of the first heat exchanger is communicated with a desorption inlet pipeline, a desorption outlet pipeline of the active carbon adsorption device is connected with a shell side inlet of the first heat exchanger, a shell side outlet of the first heat exchanger is connected with a shell side inlet of the second heat exchanger, a shell side outlet of the second heat exchanger is connected with a shell side inlet of the third heat exchanger, a gas phase outlet of the third heat exchanger is connected with an exhaust gas inlet of the absorption tower, a rich liquid outlet of the absorption tower is connected with a tube side inlet of the third heat exchanger, a liquid phase outlet of the third heat exchanger is connected with a tube side inlet of the second heat exchanger, and a rich liquid outlet of the third heat exchanger is communicated with a rich liquid inlet of the third heat exchanger.

3. The energy utilization system for polysilicon tail gas treatment according to claim 2, further comprising a fourth heat exchanger, wherein the tube side outlets of the second heat exchanger and the third heat exchanger are both communicated with the tube side inlet of the fourth heat exchanger, the tube side outlet of the fourth heat exchanger is connected with the rich liquid inlet of the resolution tower, the lean liquid outlet of the resolution tower is connected with the shell side inlet of the fourth heat exchanger, and the shell side outlet of the fourth heat exchanger is communicated with the lean liquid inlet of the absorption tower.

4. The energy utilization system for polysilicon tail gas treatment according to claim 3, further comprising a fifth heat exchanger, wherein a tube side outlet of the third heat exchanger is connected to a tube side inlet of the fifth heat exchanger, a tube side outlet of the fifth heat exchanger is connected to a tube side inlet of the fourth heat exchanger, a shell side outlet of the fourth heat exchanger is connected to a shell side inlet of the fifth heat exchanger, and a shell side outlet of the fifth heat exchanger is connected to a lean liquid inlet of the absorber.

5. The energy utilization system for polysilicon tail gas treatment according to claim 4, wherein a chlorosilane recovery pipeline is connected to a tube side outlet of the fifth heat exchanger, or a chlorosilane recovery pipeline is connected to a tube side inlet of the fifth heat exchanger.

6. The energy utilization system for polysilicon tail gas treatment according to claim 2, further comprising a first heater, wherein a tube side outlet of the first heat exchanger is connected to a heating inlet of the first heater, and wherein a heating outlet of the first heater is connected to a desorption inlet of the activated carbon adsorption device.

7. The energy utilization system for treating polysilicon tail gas according to claim 2, further comprising a polysilicon reduction furnace and a cooling heat exchange system, wherein the tail gas outlet of the polysilicon reduction furnace is connected with the tail gas inlet of the cooling heat exchange system, the gas phase outlet of the cooling heat exchange system is connected with the waste gas inlet of the absorption tower, the liquid phase outlet of the cooling heat exchange system is connected with the tube side inlet of the second heat exchanger, the cold hydrogen outlet of the absorption tower is connected with the refrigerant inlet of the cooling heat exchange system, and the refrigerant outlet of the cooling heat exchange system is connected with the adsorption inlet of the activated carbon adsorption device.

8. The energy utilization system for polysilicon tail gas treatment according to claim 7, further comprising a silicon dust removal device (800), wherein a tail gas outlet of the polysilicon reduction furnace is connected to an inlet of the silicon dust removal device, and an outlet of the silicon dust removal device is connected to a tail gas inlet of the cooling heat exchange system.