KR101727938B1 - Method and apparatus for regenerating liquid desiccants of gas dehydration - Google Patents

Abstract

The present invention relates to a regeneration method and regeneration apparatus for liquid desiccant used for gas dehydration in a gas, wherein an additive is injected into a liquid desiccant containing moisture to azeotropically distill the liquid desiccant and the additive it is possible to increase the regeneration purity of the liquid desiccant to 99.99 wt% or more by utilizing entrainer-assisted azeotropic stripping, which removes moisture through azeotropic distillation, and has a low solubility in water as the additive The use of Decane makes it easy to recover and reuse additive, which reduces the cost of the process and eliminates environmental pollution due to the release of additives.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method and apparatus for regenerating a liquid desiccant used for removing moisture in a gas,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regeneration method and regeneration apparatus for a liquid desiccant used for gas dehydration in a gas and more particularly to a regeneration method and regeneration apparatus for regeneration of a liquid desiccant by injecting an additive into a liquid desiccant containing moisture, A high efficiency regeneration method or apparatus capable of raising the regeneration purity of the liquid desiccant to 99.999 wt% or more by utilizing entrainer-assisted azeotropic stripping of moisture through azeotropic distillation of the additive .

Natural gas transported by boat is converted to liquefied natural gas (LNG) at -162 ° C by removing impurities in natural gas and cooling it to facilitate transport and storage. In this process, the moisture remaining in the natural gas may change into ice, which may lead to clogging of the pipe or valve, so the natural gas must be removed before cooling. In addition, even when natural gas is transported through piping in a gaseous state without liquefaction, moisture in the natural gas forms a gas hydrate through the bonding with carbon dioxide or various hydrocarbon compounds, thereby blocking the pipe.

In order to solve this problem, the concentration of water in the natural gas must be lower than the allowable concentration, and the pipeline gas quality for the pipeline transportation of the natural gas is about 2 to 7 lb H ₂ O / _{MMSCF (42 ~ 147 ppmw H 2} O) , and the biogas (bio gas) or landfill gas (land fill gas) is able to increase the heating value of the gas by removing the moisture contained in the gas, the gas within the water removal step for the importance of the gas dehydration process is increasing.

Generally, a method of removing water contained in a gas includes a method of adsorbing water vapor using a liquid material having hygroscopicity or a solid material having dewaterability, and a method of adsorbing water vapor using compression or cooling There is a method of condensing water vapor. The most widely used method for removing water from the gas is a method of absorbing water contained in the gas by using a glycol-based liquid desiccant having a hygroscopic property.

In order to increase the process cost and efficiency in the process of removing moisture in the gas using such a liquid desiccant, the liquid desiccant should be regenerated and used again in such a manner as to remove water contained in the used liquid desiccant.

U.S. Patent No. 3,105,748 discloses a technique for regenerating a liquid desiccant containing water at normal pressure and high temperature using a reboiler 350 and a stripping apparatus 370 (see FIG. 1) Since the vapor pressure and the thermal decomposition temperature are different depending on the kind of the glycol used as the liquid desiccant, the temperature of the reboiler 350 depends on the specific type of glycol used. For example, in the case of triethylene glycol (TEG), regeneration is carried out at a temperature of 204 DEG C or less of the reboiler 350 (pyrolysis temperature of triethylene glycol is 204 DEG C), and triethylene glycol The purity is about 98.6 wt% at maximum. In the method of regenerating the liquid desiccant using reboiler only, when the regeneration temperature of the liquid desiccant is equal to or higher than the pyrolysis temperature in the re-boiling, an organic acid as a pyrolysis product is formed to cause corrosion of the apparatus, It is hard to get. The triethylene glycol, which is primarily regenerated in the re-boiler 350, can undergo a second regeneration step through a dry gas in a stripping apparatus, The purity of triethylene glycol that can be obtained is about 99.96 wt%. However, the stripping gas used in the stripping process for increasing the purity of the liquid desiccant is burned in the flare stack, and a large amount of greenhouse gas is discharged.

On the other hand, U.S. Patent No. 3,349,544 discloses a process for regenerating a glycol-based liquid desiccant with high purity through azeotropic distillation of water and BTEX additives (benzene, toluene, ethylbenzene, xylene). Also, U.S. Patent No. 5,643,421 discloses a method of removing water from a stripping agent used for water removal of a liquid desiccant using a solid dessiccant to provide a glycol purity of about 95-98 wt% (Naphtha), natural gasoline, a boiling point of 40 to 160 ° C, and a boiling point of 40 to 160 ° C. C, aliphatic hydrocarbons, aromatic hydrocarbons, and the like.

However, in such a case, environmental pollution and disposal cost problems such as the problem of BTEX treatment dissolved in the produced water, the discharge of the additive such as BTEX, and the disposal cost are incurred, and thus there is a problem in efficiency and economical efficiency of the process.

U.S. Patent No. 3,105,748 (Oct. 19, 1963) United States Patent No. 3,349,544 (October 31, 1967) U. S. Patent No. 5,643, 421 (1997. 07. 01.)

The present invention provides a regeneration method and regeneration apparatus for a liquid desiccant that removes moisture of a liquid desiccant through azeotropic distillation of a liquid desiccant containing moisture and an additive in a gas dehydration process in a gas Increase the regeneration purity of the liquid desiccant to 99.99 wt% or more and make it easy to recover and reuse by using a small amount of additive with very low solubility in water than BTEX without the use of BTEX additive. And the like.

In order to achieve the above object, the present invention relates to a method for regenerating a liquid desiccant used for gas dehydration in a gas, wherein a liquid desiccant containing moisture is reboiler 16, Lt; / RTI > And a first separating step of removing water from the liquid desiccant containing moisture through distillation at the re-boiling point (16). The present invention also provides a method for regenerating a liquid desiccant used for gas dehydration in a gas.

On the other hand, in the primary separation step, the additive is introduced into the re-boiling portion 16, and the moisture is separated from the liquid desiccant containing moisture through azeotropic distillation at the re-boiling portion 16. The present invention also relates to a process for the production of a water-borne liquor comprising the steps of introducing a water-containing liquid desiccant into a still column 15; And the distillation tower (15), and separating moisture from the liquid desiccant through azeotropic distillation in the distillation tower (15), wherein the step of injecting comprises the step of separating the liquid desiccant containing moisture from the distillation tower Is introduced into the re-boiling (16).

The present invention also relates to a process for the production of a liquid detergent composition comprising the steps of introducing a liquid desiccant subjected to primary separation into a stripping column 17 from a re-boiler 16; And a second separation step in which the additive is introduced into the deasphalting tower 17 and water remaining in the liquid desiccant is further removed through azeotropic distillation in the deascalter tower 17. [

In the present invention, the liquid desiccant containing water is introduced into the reflux column 12 through the mixture vapor discharged from the upper portion of the re-boiler 16 before the introduction of the liquid desiccant, so that heat exchange occurs. Separating the mixture vapor discharged from the reflux tower (12) into a separator (19) to recover the additive; Heating the recovered additive with a heater (20); And the additive heated by the heater 20 is injected into the re-boiler 16. At this time, the mixture steam includes moisture and an additive.

On the other hand, the liquid desiccant used for removing moisture in the gas includes ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol ), Or a mixture thereof. It is preferable that the additive used in the present invention includes a decane or a decane derivative.

It is also preferred that the additive is in the range of 5 to 20 wt% of the total mixture comprising moisture, liquid desiccant and additives in the stripping column.

The present invention provides, in another embodiment, a regenerator for a liquid desiccant used for gas dehydration in a gas, comprising a reboiler 16 into which a liquid desiccant containing moisture is introduced At this time, the moisture is firstly separated from the liquid desiccant containing moisture through azeotropic distillation at the re-boiling (16).

On the other hand, in the primary separation, the additive is introduced into the reboiler 16, and moisture is separated from the liquid desiccant containing moisture through azeotropic distillation at the reboiler 16. The present invention further includes a still column 15 into which a liquid desiccant containing moisture is introduced so that the additive is introduced into the distillation column 15 and moisture is removed from the liquid desiccant by azeotropic distillation in the distillation column 15. [ And the liquid desiccant containing water which is separated and introduced into the re-rinse (16) is introduced from the distillation tower (15).

The present invention may further include a stripping column 17 into which a liquid desiccant having been primarily separated from the re-boiler 16 is introduced. The additive is introduced into the de-loading tower 17, (17) is subjected to secondary separation in which moisture remaining in the liquid desiccant is further removed through azeotropic distillation.

The present invention as described above includes a reflux column 12 for heat exchange with the vapor mixture discharged from the upper portion of the reboiler 16 before the liquid desiccant containing moisture is introduced into the reboiler 16; A separator 19 for separating the mixture vapor discharged from the reflux tower 12 and recovering the additive; And a heater 20 to which the recovered additive is heated. At this time, the additive heated by the heater 20 is injected into the re-boiler 16, and the mixture boiler is characterized by containing moisture and an additive.

On the other hand, the liquid desiccant used for removing moisture in the gas includes ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol ), Or a mixture thereof. It is preferable that the additive used in the present invention includes a decane or a decane derivative.

It is also preferable that the additive is 5 to 20 wt% of the entire mixture including the re-boiling and the water, the liquid desiccant and the additive in the distillation column.

As described above, the present invention relates to a process for regenerating a liquid desiccant which removes moisture of a liquid desiccant through azeotropic distillation of a liquid desiccant containing water and an additive in a gas dehydration process in a gas, And the regeneration purity of the liquid desiccant is increased to 99.999 wt% or more.

In addition, the present invention has an advantage that the use of Decane having a low solubility in water as an additive facilitates the recovery and reuse of the additive, thereby reducing the process cost and environmental pollution due to the discharge of the additive.

FIG. 1 schematically shows a method and apparatus for removing moisture of a liquid desiccant using a reboiler and a stripper, which are conventional techniques.
FIG. 2 is a diagram showing the primary separation step of distilling the liquid desiccant in the re-boiling of the present invention; And a second separation step of injecting an additive into a stripping column and further removing moisture of the liquid desiccant by azeotropic distillation.
3 schematically shows a regeneration method and apparatus of a liquid desiccant comprising a step of removing the moisture of the liquid desiccant by azeotropic distillation by injecting an additive into the reboiler and still column of the present invention.
FIG. 4 shows experimental results showing the regeneration purity of TEG (triethylene glycol) according to the type of additive.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Prior to the description, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical concept of the present invention.

Throughout this specification, when an element is referred to as "including" an element, it is understood that it may include other elements as well, without departing from the other elements unless specifically stated otherwise.

Throughout this specification, when a member is " on " another member, this includes not only when the member is in contact with another member, but also when there is another member between the two members.

FIG. 2 is a diagram showing the primary separation step of distilling the liquid desiccant in the re-boiling of the present invention; And a second separation step of injecting an additive into a stripping column and further removing moisture of the liquid desiccant by azeotropic distillation.

2, a wet gas containing water is supplied to an absorber 11 in order to regenerate a liquid desiccant used for gas dehydration in the gas, And the moisture removed by the liquid desiccant injected into the absorption tower 11 is discharged through the discharge pipe 32 as a dry gas and the liquid desiccant Is introduced into the reflux column 12 through another supply pipe 33.

The gas may be, but is not limited to, natural gas, bio gas, land fill gas, refinery gas, carbon dioxide, or synthesis gas .

The liquid desiccant may be selected from the group consisting of ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG) and tetraethylene glycol (TTEG) One or more glycol based compounds, or mixtures thereof.

The liquid desiccant used is heat exchanged in a reflux column 12 with a mixture of steam containing water absorbed from the gas and moisture and additives removed in the first and second separation steps to be described later. As described above, the liquid desiccant having a low temperature and the high-temperature mixed steam are heat-exchanged, so that the liquid desiccant remaining in the mixed steam can be condensed to reduce the loss of the liquid desiccant.

The liquid desiccant containing the moisture discharged from the reflux tower 12 is introduced into the flash tank 13 through the supply pipe 34 so as to be separated from the gas partially contained in the liquid desiccant during the dehydration of the gas, and the gas is supplied to the other use place through the supply pipe 35.

The liquid desiccant containing the moisture separated from the gas is introduced into the heat exchanger 14 along the supply pipe 36 to be supplied to the supply pipe 41 connected to the stripping column 17 of the present invention, Exchanged with the dry liquid desiccant discharged through the feed line 37, and then introduced into the still column 15 through the supply line 37.

The liquid desiccant containing water introduced into the distillation column 15 is introduced into a reboiler 16 connected to the distillation column 15 and is heated and distilled to undergo a primary separation step in which moisture is removed.

The distillation column may include a solid or hollow chain packing having a surface on which two phases of gas-liquid can efficiently transfer heat or substance to each other. Accordingly, the loss of the liquid desiccant can be reduced by effectively removing moisture through mass transfer between the water vapor (gas) and the liquid desiccant (liquid) containing water in the distillation column. The packing may use random packing or structured packing.

The liquid desiccant having undergone the primary separation step is introduced into the stripping tower 17 through the supply pipe 39. The additive is injected into the stripping tower 17 to remove moisture remaining in the liquid additive through azeotropic distillation or stripping The second separation step is performed.

At this time, the additive may be injected in a state where the liquid phase and the vapor phase coexist, wherein the liquid portion of the additive and moisture form an azeotropic mixture having an azeotropic point of less than about 100 캜, and are separated from the liquid desiccant by azeotropically distilling together. The gas phase portion of the additive is a stripping gas, which acts to remove moisture contained in the liquid desiccant.

The additive may comprise a Decane or Decane derivative and is preferably 5 to 20 wt% of the total mixture comprising water, a liquid desiccant and additives in the stripper, no.

The liquid desiccant which has undergone the second separation step in the stripping tower 17 is introduced into the heat exchanger 14 through the supply pipe 41 and exchanged with the liquid desiccant discharged from the evaporation tank 13, And can be reused by being injected again into the absorption tower 11 through the supply pipe 43 connected to the surge drum 18 through the surge drum 18 through the pipe 18.

On the other hand, in the second separation stage, the vapor mixture of the distillated water and the additive is fed to the reflux tower 12 together with the steam of the mixture of water and the additive distilled in the first separation stage via the feed pipe 40 connected to the re- Through a feed pipe 38 connected to the feed pipe 38.

The mixed vapor discharged from the reflux tower 12 is introduced into a separator 19 through a supply pipe 44 and is separated and recovered from gases and water, The recovered additive can be reused by being injected again into the demolition tower 17 through the supply pipe 47.

At this time, when an additive including decane or decane derivative is used as the additive to be used, its solubility in water is low and it can be easily separated from water and is easy to be reused. Accordingly, problems such as environmental pollution .

As the separator 19, it is preferable to use a three-phase separator capable of separating the mixture into gas, water and additives.

A heater 20 and a valve 21 may be further disposed on the supply pipe 47 connecting the separator 19 and the stripping tower 17. The recovered additive is heated through the heater 20, And two phases of the gas phase.

Since the stripping tower 17 has no heating portion, it is more effective that the additive is added at a high temperature for the stability of the process and formation of the azeotropic mixture, more preferably at least 100 deg. C higher than the temperature of the azeotropic point, Is heated to a temperature lower than < RTI ID = 0.0 > 204 C < / RTI >

The gaseous portion of the recovered additive acts as a degassing gas to remove moisture from the liquid desiccant, and the liquid portion forms an azeotropic mixture with water to azeotropically distill water from the liquid desiccant.

The additive heated in the heater 20 is injected (48) into the stripping tower (17) through the valve (21). At this time, the flow rate sensor 22 may be installed on the supply pipe 39 through which the liquid desiccant is supplied from the re-boiler 16 to the stripping tower 17. Based on the detected flow rate, the controller 24 By controlling the valve regulator 23, it can be configured to regulate the flow rate of the additive injected into the stripping tower 17.

Fig. 3 schematically shows a regeneration method and apparatus for regenerating a liquid desiccant including a step of re-charging and adding an additive to a distillation column to remove moisture of the liquid desiccant by azeotropic distillation.

3, wet gas containing water is introduced into the absorption tower 11 along the feed pipe 31, and the absorption tower (not shown) is used to regenerate the liquid desiccant used for removing moisture in the gas, And the liquid desiccant used is discharged to the reflux tower 12 through another supply pipe 33. The liquid desiccant is discharged through the discharge pipe 32 as dry gas through the discharge pipe 32, .

The gas may be, but is not limited to, natural gas, bio gas, land fill gas, refinery gas, carbon dioxide, or synthesis gas .

The liquid desiccant may be selected from the group consisting of ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG) and tetraethylene glycol (TTEG) One or more glycol based compounds, or mixtures thereof.

The used liquid desiccant contains moisture absorbed from the gas and is heat-exchanged in the reflux tower 12 with the mixture steam containing the moisture and additives removed in the water separation step to be described later. As described above, the liquid desiccant having a low temperature and the high-temperature mixed steam are heat-exchanged, so that the liquid desiccant remaining in the mixture steam is condensed, thereby reducing the loss of the liquid desiccant.

The liquid desiccant containing water discharged from the reflux tower 12 is introduced into the evaporation tank 13 through the supply pipe 34 to be separated from the gas partially contained in the liquid desiccant during the dehydration of the gas, (35). ≪ / RTI >

The liquid desiccant containing the moisture separated from the gas is introduced into the heat exchanger 14 along the supply pipe 36 and discharged through the supply pipe 41 connected to the stripping tower 17 of the present invention. Exchanged, and then introduced into the distillation column 15 through the feed pipe 37.

At this time, the additive is introduced into the distillation column 15, so that moisture can be separated from the liquid desiccant through the azeotropic distillation in the distillation column 15.

The distillation column may include a solid or hollow chain packing having a surface on which two phases of gas-liquid can efficiently transfer heat or substance to each other. Accordingly, the loss of the liquid desiccant can be reduced by effectively removing moisture through mass transfer between the water vapor and gaseous phase additive (gas) and the liquid desiccant containing liquid (liquid) in the distillation column. The packing may use random packing or structured packing.

The liquid desiccant, from which the first moisture has been removed, is introduced into the re-boiler 16 at the distillation tower 15. The additive is introduced into the re-boiler 16, whereby the moisture is separated from the liquid desiccant containing moisture through heating and azeotropic distillation at the re-boiler 16.

The additive and water form an azeotrope with an azeotrope of less than about 100 ° C and are separated from the liquid desiccant by azeotropic distillation together.

The additive may comprise a decane or decane derivative and is preferably 5-20 wt% of the total mixture comprising moisture, liquid desiccant and additives in the distillation tower 15 and reboiler 16, It is not.

The liquid desiccant which has undergone the water separation step is introduced into the stripping tower 17 through the supply pipe 39, so that the removal of moisture may be performed.

The liquid desiccant discharged from the stripping tower 17 is introduced into the heat exchanger 14 through the supply pipe 41 to be heat-exchanged with the liquid desiccant discharged from the evaporation tank 13, It can be reused by being injected again into the absorption tower 11 through the supply pipe 43 connected to the surge drum 18 through the pipe 18.

On the other hand, in the water separation step, the steam of the mixture of the distilled water and the additive can be introduced into the reflux tower 12 through the feed pipe 38.

The mixture vapor that has passed through the reflux tower 12 is introduced into the separator 19 through the feed pipe 44 and is separated and recovered from the gas and water to recover the recovered additive Can be re-used by being injected back into refill 16 or distillation tower 15 via feed lines 49, 50.

At this time, when an additive containing decane or decane derivative is used as the additive, the solubility of the additive in water is low, so that it can be easily separated from moisture and is easily reused. As a result, problems such as environmental pollution Do not.

As the separator 19, it is preferable to use a three-phase separator capable of separating the mixture into gas, water and additives.

The heater 20 and the valve 25 may be further disposed on the supply pipe 47 connecting the separator 19 and the distillation tower 15 and the reboiler 16 and the recovered additive may be heated Thereby becoming a hot additive.

It is more effective that the additive is added at a high temperature for the stability of the reflux operation 16 and the distillation column 15 operation and more preferably at least 100 ° C above the temperature of the azeotrope and below 204 ° C below the pyrolysis temperature of the liquid desiccant Lt; / RTI >

The additive heated in the heater 20 is injected (49, 50) through the valve 25 into the distillation tower 15 or the reboiler 16. At this time, the flow rate sensor 26 can be installed on the supply pipe 37 through which the liquid desiccant is supplied from the heat exchanger 14 to the distillation tower 15. Based on the sensed flow rate, By controlling the regulator 27, it can be configured to regulate the flow rate of the additive injected into the distillation column 15 or the reboiler 16.

<Additives used in azeotropic distillation Removal ability  Evaluation>

The regeneration purity of the liquid desiccant was measured by short distillation using various additives in order to evaluate the deodorizing ability of the additives used for the azeotropic distillation of the liquid desiccant containing water. Table 1 lists the additives used in the evaluation and their chemical properties, and TEG (triethylene glycol) was used as a liquid desiccant. The condition as an additive for use in the present invention is that it forms an azeotropic compound with water, has a boiling point of less than 210 占 폚, is low in solubility in water and capable of removing a large amount of water in a small amount.

Using a distillation apparatus, a mixture of TEG and water in 97: 3 wt% was heated to 200 ° C., and 5 wt% of the additive was injected into a mixture of TEG and water. Respectively. As a result, as shown in FIG. 4, the distillation of a mixture of TEG and water using Decane showed that the purity of TEG could be increased to 99.97 wt% or more, and the amount of benzene, toluene toluene), which is a water-soluble resin. In general, higher TEG purity can be achieved with the same amount of additive if applied to the actual process of multi-stage distillation.

In addition, decane has the lowest solubility in water among the additives shown in Table 1, which is easy to recover and reuse, and the post-treatment cost of the additive is lower than that of BTEX.

Additives
(unit) Boiling point
( ^o C) Azeotropic
온도
( ^o C) Azeotropic
composition
(mol fraction additive) Solubility
(g / L H2O) decane 173.8 98.3 0.083 0.000052 cumene 152.6 95.5 0.166 0.061 benzene 80.2 69.3 0.699 1.84 toluene 110.9 102.7 0.436 0.52 ethoxybezene 170.3 98.2 0.088 0.57 acetophenone 201.9 98.0 0.033 5.5 benzyl alcohol (phenylethanol) 205.3 98.6 0.010 35 dichloro benzene 180.5 98.2 0.070 0.16 1-hexanol 157.3 98.5 0.077 5.9 octanol 194.6 100.4 0.019 0.46 1-nonanol 213.9 99.9 0.015 One butyl acetate 126.0 91.4 0.279 6.8

< Decane ( decane ) Depending on the weight ratio of additives Removal ability  Evaluation>

Table 2 shows the purity of TEG regeneration when the azeotropic distillation was carried out by distillation according to the weight ratio of decane additive to the total mixture containing water and liquid desiccant. As in the above experiment, : 3 wt% of the mixture was heated to 200 ° C, and 5 wt% of the additive was injected into a mixture of TEG and water, and the change in moisture in the TEG was measured for 20 minutes.

As shown in Table 2, when the azeotropic distillation was carried out using 5 to 20 wt% of decane additive, distillation with a short distillation showed a remarkable effect of obtaining a TEG having a purity of 99.97 wt% or more, unlike the case of using a different weight ratio. Particularly, in case of 20 wt%, 99.999 wt% or more TEG could be obtained.

However, when the weight ratio of the additive exceeds 20 wt%, the purity does not increase any more but converges to a certain value. On the contrary, in this case, there is a problem of economic cost due to overuse of the additive and a problem of deterioration of separation efficiency when recovering the used additive to the separator.

Therefore, it can be seen from this experiment that the optimum effect can be obtained when the weight ratio of the additive is 5 to 20 wt%.

In general, higher TEG purity can be achieved with the same amount of additive if applied to the actual process of multi-stage distillation.

decane additive (wt%) TEG purity (wt%) One 99.3245 3 99.6236 5 99.9712 10 99.9813 15 99.9921 17 99.9975 20 99.9995 23 99.9996 25 99.9996

31 to 50: supply pipe 20: heater
11: absorber 21: valve,
12: reflux column 22: flow rate sensor
13: flash tank 23: valve regulator
14: heat exchanger 24:
15: still column 25: valve
16: Reboiler 26: Flow sensor
17: stripping column 27: valve regulator
18: Surge drum 28:
19: separator

Claims (18)

In a method for regenerating a liquid desiccant,
Introducing the liquid desiccant containing moisture into the still column (15);
An additive is introduced into the distillation column 15 to separate water from the liquid desiccant first through azeotropic distillation in the distillation column 15;
An injection step in which the liquid desiccant subjected to the primary separation is introduced into the reboiler 16 from the distillation column 15;
A second separation step in which water is removed from the liquid desiccant containing the moisture through distillation at the re-boiler (16);
The liquid desiccant having undergone the secondary separation is introduced into the stripping column 17 from the re-boiler 16; And
And a tertiary separation step in which the additive is introduced into the deodorization tower 17 and moisture remaining in the liquid desiccant is further removed through azeotropic distillation in the deodorization tower 17,
Characterized in that the distillation column comprises a solid or hollow packing having a surface inside which two phases of gas-liquid can efficiently transfer heat or substance to each other. A method for regenerating a liquid desiccant for use in gas dehydration. The method according to claim 1,
Wherein the secondary separation step comprises:
Characterized in that the additive is introduced into the re-boiler (16), and water is separated from the liquid desiccant containing the moisture through the azeotropic distillation in the re-boiler (16) A method for regenerating a desiccant. delete delete 3. The method according to any one of claims 1 to 3,
A liquid desiccant containing moisture is introduced into the reflux column 12 and the mixture vapor discharged from the top of the reboiler 16 before the reboiler 16 is introduced into the reboiler 16 A step of heat exchange;
Separating the mixed vapor discharged from the reflux tower (12) into a separator (19) to recover the additive;
Heating the recovered additive with a heater (20); And
Further comprising injecting the additive heated by the heater (20) into the re-boiler (16)
Characterized in that the mixture steam contains moisture and an additive. The method according to claim 1,
The liquid desiccant may be at least one selected from the group consisting of ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol Or a mixture thereof. &Lt; Desc / Clms Page number 24 &gt; The method according to claim 1,
Characterized in that the additive is 5 to 20 wt% of the total mixture in the stripping tower (17), and the mixture comprises water, a liquid desiccant and an additive. . The method according to claim 1,
Characterized in that the additive is 5 to 20 wt% of the total mixture in the re-boiler (16) and the distillation tower (15), and the mixture comprises water, a liquid desiccant and additives. A method for regenerating a liquid desiccant. 3. The method according to any one of claims 1 to 3,
Characterized in that the additive comprises Decane. &Lt; Desc / Clms Page number 13 &gt; 1. A regenerator for a liquid desiccant,
A still column 15 into which a liquid desiccant containing moisture is introduced,
The additive is introduced into the distillation column (15), and water is firstly separated from the liquid desiccant through azeotropic distillation in the distillation column (15)
And a reboiler 16 into which the liquid desiccant having undergone the primary separation from the distillation tower 15 is introduced,
The moisture is secondarily separated from the liquid desiccant containing the moisture through the azeotropic distillation at the re-boiler (16)
And a stripping column (17) into which the liquid desiccant having undergone the secondary separation from the re-boiler (16) is introduced,
The additive is introduced into the deodorizing tower 17 to perform tertiary separation in which water remaining in the liquid desiccant is further removed through azeotropic distillation in the deodorization tower 17,
Characterized in that the distillation column includes a solid or hollow packing having two surfaces in which gas-liquid phases can efficiently transfer heat or substances to each other. , A regeneration device for the liquid desiccant used for gas dehydration. 11. The method of claim 10,
In the secondary separation,
Characterized in that the additive is introduced into the re-boiler (16) and water is separated from the liquid desiccant containing the water through azeotropic distillation in the re-boiler (16) Playback apparatus. delete delete 12. The method according to any one of claims 10 to 11,
A reflux column 12 for heat exchange with the vapor mixture discharged from the upper portion of the reboiler 16 before the liquid desiccant containing the moisture is introduced into the reboiler 16;
A separator 19 for separating the mixture vapor discharged from the reflux tower 12 and recovering the additive; And
And a heater (20) heating the recovered additive,
Characterized in that an additive heated by the heater (20) is injected into the re-boiler (16), and the mixture steam contains moisture and an additive. 11. The method of claim 10,
The liquid desiccant may be at least one selected from the group consisting of ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol Or a mixture thereof. The apparatus for regenerating a liquid desiccant used for removing moisture in a gas. 11. The method of claim 10,
Characterized in that the additive is in the range of 5 to 20 wt% of the total mixture in the stripping tower (17), and the mixture comprises moisture, a liquid desiccant and an additive. . 11. The method of claim 10,
Characterized in that the additive is 5 to 20 wt% of the total mixture in the reboiler (16) and the distillation tower (15), and the mixture comprises water, a liquid desiccant and an additive. Wherein the liquid desiccant is recycled. 12. The method according to any one of claims 10 to 11,
Characterized in that the additive comprises Decane. &Lt; RTI ID = 0.0 &gt; 8. &lt; / RTI &gt;

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