KR20130140658A - Ammonia purification system and method for purifying ammonia - Google Patents

Abstract

The present invention provides an ammonia purification system that can purify ammonia by a simplified method, and can efficiently purify ammonia by suppressing energy consumption.
The ammonia purification system 100 includes an oil adsorption tower 2, a high boiling point impurity adsorption unit 3, and a vaporizer 5. The oil adsorption tower 2 adsorbs and removes the oil contained in the liquid crude ammonia with activated carbon. The high boiling point impurity adsorption part 3 adsorbs and removes the high boiling point impurity contained in liquid ammonia with synthetic zeolite. The vaporizer 5 vaporizes liquid ammonia derived from the high boiling point impurity adsorption unit 3 at a predetermined vaporization rate, and separates and removes the low boiling point impurity as a gaseous component.

Description

Ammonia Purification System and Purification Method of Ammonia {AMMONIA PURIFICATION SYSTEM AND METHOD FOR PURIFYING AMMONIA}

The present invention relates to an ammonia purification system for purifying crude ammonia and a method for purifying ammonia.

In the semiconductor manufacturing process and the liquid crystal manufacturing process, ammonia of high purity is used as a treatment agent used for production of a nitride film and the like. Such high purity ammonia is obtained by purifying crude ammonia to remove impurities.

Crude ammonia includes low-order hydrocarbons such as methane, ethane and propane, higher-order hydrocarbons having more carbon atoms, water, and low-boiling gases such as hydrogen, nitrogen, oxygen, argon and carbon monoxide as impurities. Generally, the purity of available ammonia is about 99.5% by weight.

The way in which the impurities in ammonia affects depends on the kind of process in which ammonia is used in the semiconductor manufacturing process and the liquid crystal manufacturing process. The purity of ammonia is required to be 99.9999% by weight or more, and more preferably 99.99999% by weight or more.

As a method for removing impurities contained in crude ammonia, a method of adsorbing and removing impurities using an adsorbent such as silica gel, synthetic zeolite, activated carbon, and the like is known.

For example, Patent Document 1 includes a first distillation column for removing high-boiling impurities from liquid crude ammonia, an adsorption column for adsorption and removal of impurities (mainly moisture) contained in gaseous ammonia derived from the first distillation column with an adsorbent; Ammonia refining system is disclosed that includes a second distillation column for removing low boiling point impurities from gaseous ammonia derived from an adsorption column. In addition, Patent Document 2 discloses a method of purifying ammonia by distilling after adsorbing and removing water contained in gaseous crude ammonia with an adsorbent made of barium oxide.

Japanese Patent Application Laid-Open No. 2006-206410 Japanese Patent Publication No. 2003-183021

In the technique of purifying ammonia disclosed in Patent Documents 1 and 2, the impurities contained in the crude ammonia are adsorbed and removed in the adsorption column and further distilled in the distillation column to purify the ammonia, but the gaseous ammonia after purification derived from the distillation column It is condensed and recovered as liquid ammonia. That is, in the technique for purifying ammonia disclosed in Patent Documents 1 and 2, the impurities contained in crude ammonia are adsorbed and distilled off, and condensed to obtain a purified liquid ammonia. It cannot be said that much energy is required to purify ammonia.

Accordingly, it is an object of the present invention to provide an ammonia purification system and a method for purifying ammonia that can purify ammonia by a simplified method and can efficiently purify ammonia by suppressing energy consumption.

The present invention is an ammonia purification system for purifying crude ammonia containing impurities,

A storage part for storing liquid ammonia,

A first adsorption unit for adsorbing and removing the oil contained in the liquid crude ammonia stored in the reservoir with activated carbon to derive liquid ammonia;

A second adsorption unit which adsorbs and removes the high boiling point impurity higher than ammonia contained in the liquid ammonia derived from the first adsorption unit by using a synthetic zeolite to derive the liquid ammonia;

The liquid ammonia derived from the second adsorption unit is vaporized at a predetermined vaporization rate and separated into a gas phase component and a liquid component to separate and remove low boiling point impurities having a lower boiling point than ammonia as a gas phase component to obtain purified liquid ammonia as a liquid component. Ammonia purification system comprising a vaporization unit.

In addition, the ammonia purification system of the present invention further includes an analysis unit for analyzing the concentration of impurities contained in the liquid ammonia derived from the second adsorption unit,

It is preferable to set the said predetermined vaporization rate when the said vaporization part vaporizes the liquid ammonia derived from the said 2nd adsorption part based on the analysis result by the said analysis part.

In the ammonia purification system of the present invention, the predetermined vaporization rate when the vaporization unit vaporizes liquid ammonia derived from the second adsorption unit is preferably set to 5 to 20% by volume.

Moreover, in the ammonia purification system of this invention, it is preferable that the said vaporization part vaporizes liquid ammonia derived from the said 2nd adsorption part at the temperature of -50-30 degreeC, and isolate | separates into a gaseous-phase component and a liquid phase component.

In addition, the ammonia purification system of the present invention preferably has the second adsorption portion having a first adsorption region filled with MS-3A as a synthetic zeolite and a second adsorption region filled with MS-13X as a synthetic zeolite.

In addition, the ammonia purification system of the present invention is a plurality of adsorption units for adsorbing and removing high-boiling impurities contained in the liquid ammonia derived from the first adsorption unit, and the plurality of adsorption units connected in series or in parallel. It is preferable to have a part.

In addition, the present invention is a method for purifying crude ammonia containing impurities,

A storage process for storing liquid crude ammonia,

A first adsorption step of adsorbing and removing the oil contained in the liquid crude ammonia stored in the storage step with activated carbon;

A second adsorption step of adsorbing and removing a high boiling point impurity having a higher boiling point than that of ammonia by the synthetic zeolite, which is contained in the liquid ammonia in which the oil is adsorbed and removed in the first adsorption step;

In the second adsorption process, the liquid ammonia from which the high boiling point impurities have been adsorbed and removed is vaporized at a predetermined vaporization rate and separated into a gaseous phase component and a liquid phase component. And a vaporization step of obtaining the purified liquid ammonia.

(Effects of the Invention)

According to the present invention, the ammonia purification system is a system for purifying crude ammonia containing impurities, and includes a storage portion, a first adsorption portion, a second adsorption portion, and a vaporization portion. The 1st adsorption | suction part adsorbs and removes the oil content contained in the liquid crude ammonia stored by the storage part with activated carbon. The second adsorption unit adsorbs and removes the high-boiling impurities contained in the liquid ammonia derived from the first adsorption unit by synthetic zeolite. The vaporization unit vaporizes the liquid ammonia derived from the second adsorption unit at a predetermined vaporization rate into a gaseous component and a liquid phase component to separate and remove low boiling impurities as a gaseous component to obtain purified liquid ammonia as a liquid component.

In the ammonia purification system of the present invention, the vaporization unit vaporizes liquid ammonia after adsorption and removal of high boiling point impurities such as oil, water, and higher hydrocarbons at a predetermined vaporization rate to separate gaseous and liquid components into methane, ethane, propane, and the like. Low-boiling impurities such as and low-boiling impurities such as low-boiling gases such as hydrogen, nitrogen, oxygen, argon and carbon monoxide can be separated and removed as gaseous components to obtain purified liquid ammonia as a liquid component. Therefore, in the ammonia purification system of the present invention, ammonia can be purified by a simplified method without distillation with reflux as in the prior art, and ammonia can be efficiently purified by suppressing energy consumption. .

In addition, according to the present invention, the ammonia purification system further includes an analysis unit. This analysis section analyzes the concentration of impurities contained in the liquid ammonia derived from the second adsorption section. And the vaporization part sets the vaporization rate at the time of vaporizing the liquid ammonia derived from the 2nd adsorption part based on the analysis result by an analysis part. Thus, since the vaporization part sets the vaporization rate at the time of vaporizing liquid ammonia according to the analysis result by an analysis part, it can suppress the consumption of energy and can refine | purify ammonia efficiently.

According to the present invention, the vaporization unit vaporizes the liquid ammonia derived from the second adsorption unit at a vaporization rate of 5 to 20% by volume to separate the gas phase component and the liquid phase component. Thereby, the low boiling point impurity contained in the liquid ammonia after the oil component and the high boiling point impurity are removed by adsorption can be separated and removed as a gaseous component to obtain a good yield of the liquid ammonia purified as the liquid component.

According to the present invention, the vaporization unit vaporizes the liquid ammonia derived from the second adsorption unit at a temperature of -50 to 30 ° C to separate the gaseous phase component and the liquid phase component. As a result, liquid ammonia after the adsorption and removal of oil and high-boiling impurities can be efficiently vaporized to obtain liquid ammonia from which the low-boiling impurities are separated and removed, and the purity of the liquid ammonia can be increased.

In addition, according to the present invention, the second adsorption portion has a first adsorption region filled with MS-3A as a synthetic zeolite and a second adsorption region filled with MS-13X. MS-3A of synthetic zeolites is an adsorbent with excellent adsorption capacity for water, and MS-13X is an adsorbent with excellent adsorption capacity for water and hydrocarbons. The second adsorption section having the adsorption region filled with MS-3A and MS-13X having such adsorption capacity efficiently adsorbs high-boiling impurities such as moisture and higher-order hydrocarbons contained in the liquid ammonia derived from the first adsorption section. Can be removed

Moreover, according to this invention, a 2nd adsorption part has several adsorption parts connected in series or in parallel. When the second adsorption section has a plurality of adsorption sections connected in series, it is possible to improve the adsorption and removal ability to the high boiling point impurities contained in the liquid ammonia derived from the first adsorption section. In addition, in the case where the second adsorption unit has a plurality of adsorption units connected in parallel, the liquid ammonia derived from the first adsorption unit can be introduced in a state of distinguishing each of the plurality of adsorption units connected in parallel. While the adsorption unit is being removed by adsorption, the other adsorption unit which has been used can be regenerated to enable the adsorption removal operation again at the other adsorption unit which has been used.

Moreover, according to this invention, the refinement | purification method of ammonia is a method of refine | purifying crude ammonia containing an impurity, and includes a storage process, a 1st adsorption process, a 2nd adsorption process, and a vaporization process. In the first adsorption step, the oil contained in the liquid crude ammonia stored in the storage step is adsorbed and removed by activated carbon. In the second adsorption step, high boiling point impurities contained in the liquid ammonia in which the oil is adsorbed and removed in the first adsorption step are adsorbed and removed by the synthetic zeolite. In the vaporization step, the liquid ammonia from which the high boiling point impurities are adsorbed and removed in the second adsorption step is vaporized at a predetermined vaporization rate and separated into a gaseous phase component and a liquid phase component to separate and remove the low boiling point impurities as a gaseous phase component to be purified as a liquid component. Obtain liquid ammonia.

In the method for purifying ammonia of the present invention, liquid ammonia after adsorption and removal of high boiling point impurities such as oil, water, and higher hydrocarbons in the vaporization step is vaporized at a predetermined vaporization rate and separated into a gaseous phase component and a liquid phase component. Lower hydrocarbons such as propane and low boiling impurities such as hydrogen, nitrogen, oxygen, argon, carbon monoxide, and the like, can be separated and removed as gaseous components to obtain liquid ammonia purified as a liquid component. Therefore, in the purification method of ammonia of the present invention, ammonia can be purified by a simplified method without distillation with reflux as in the prior art, and ammonia can be efficiently purified by suppressing energy consumption. have.

Fig. 1 is a view showing a configuration of an ammonia purification system 100 according to a first embodiment of the present invention.
2 is a diagram showing the configuration of the ammonia purification system 200 according to the second embodiment of the present invention.

Fig. 1 is a view showing a configuration of an ammonia purification system 100 according to a first embodiment of the present invention. The ammonia purification system 100 of this embodiment is a system which refine | purifies liquid crude ammonia containing an impurity. The liquid crude ammonia contains oil and lower hydrocarbons such as methane, ethane and propane, higher hydrocarbons having more carbon atoms, water, and low boiling gases such as hydrogen, nitrogen, oxygen, argon and carbon monoxide as impurities. That is, the liquid crude ammonia contains oil, low boiling impurities such as lower hydrocarbons and lower boiling gases having a lower boiling point than ammonia (boiling point -33.44 ° C), and high boiling impurities such as higher hydrocarbons and moisture having higher boiling points than ammonia. .

The ammonia purification system 100 includes a storage tank 1 as a reservoir, an oil adsorption tower 2 as a first adsorption unit, a high boiling point impurity adsorption unit 3 as a second adsorption unit, an analysis unit 4 and a vaporizer 5 as a vaporization unit. , And a recovery tank 6. Moreover, the ammonia purification system 100 implements the purification method of ammonia by this invention, performs a storage process in the storage tank 1, performs a 1st adsorption process in the oil adsorption tower 2, and high boiling point impurity. The adsorption part 3 performs a 2nd adsorption process, and the vaporizer | carburetor 5 performs a vaporization process.

The storage tank 1 stores the ammonia. In this embodiment, the crude ammonia stored in the storage tank 1 is about 99.5 weight% of purity.

The storage tank 1 is not particularly limited as long as it is a heat storage container having pressure resistance and corrosion resistance. This storage tank 1 stores crude ammonia as liquid ammonia, and is controlled so that temperature and pressure become constant conditions. In the state where the storage tank 1 stored liquid crude ammonia, the gaseous phase is formed in the upper part of the storage tank 1, and the liquid phase is formed in the lower part. In this embodiment, when ammonia is led out from the storage tank 1 to the oil adsorption | suction adsorption tower 2, coammonia is derived from the said liquid phase as liquid coarse ammonia. A first pipe 81 is connected between the storage tank 1 and the oil adsorption tower 2, and the liquid crude ammonia derived from the storage tank 1 flows through the first pipe 81 and passes through the oil adsorption tower ( 2) is supplied.

The 1st piping 81 is provided with the 1st valve 811 which opens or closes the flow path in the 1st piping 81. At the time of supplying the liquid crude ammonia to the oil absorption tower 2, the first valve 811 is opened so that the liquid crude ammonia enters the first pipe 81 from the storage tank 1 toward the oil absorption tower 2. Flows through.

The liquid coarse ammonia derived from the storage tank 1 contains about 2 to 15 ppm of oil such as lubricating oil for equipment such as a compressor. The content of the oil contained in the liquid coarse ammonia can be determined by measuring the remaining component after vaporizing the coarse ammonia with an oil concentration meter (OCMA-355, manufactured by Horiba Seisakujo Co., Ltd.).

The oil adsorption tower 2 adsorbs and removes the oil contained in the liquid crude ammonia derived from the storage tank 1 with an adsorbent made of activated carbon. Examples of the activated carbon filled in the oil absorption tower 2 include palm shell activated carbon (Kuraray GG, Kuraray Chemical Co., Ltd.) and the like.

The liquid ammonia derived from the oil adsorption tower 2 flows through the second pipe 82 and is supplied to the third pipe 83 connected to the high boiling point impurity adsorption unit 3.

The second pipe 82 is provided with a filter 7 for removing heavy metals contained in the liquid ammonia flowing from the oil adsorption tower 2 toward the third pipe 83. In the present embodiment, the filter 7 has a two-layer structure in which a 5 μm filter made of polypropylene (PP) and a 0.01 μm filter made of polytetrafluoroethylene (PTFE) / PP are connected in series. In addition, the filter 7 is not limited to being directly connected to the downstream side of the flow passage direction of the ammonia flow than the oil adsorption tower 2, and is disposed on the downstream side of the ammonia flow passage direction than the high boiling point impurity adsorption section 3 described later. You may arrange | position to. In addition, although the structure which installs one filter 7 in the 2nd piping 82 was shown in FIG. 1, it is not limited to this structure, The several filter 7 is connected in parallel to the 2nd piping 82, In addition, in FIG. You may do so. For example, when the two filters 7 are connected to the 2nd piping 82 in parallel, the heavy metal contained in the liquid ammonia derived from the oil adsorption | suction tower 2 is carried out by the one filter 7, During the filtration separation removal, the replacement operation of the other used filter 7 can be performed.

Moreover, the 2nd valve 821 which opens or closes the flow path in the 2nd piping 82 is provided in the 2nd piping 82 more upstream than the filter 7 in the flow passage direction of ammonia. At the time of supplying the liquid ammonia oil absorption tower 2 from the oil adsorption tower 2 toward the third pipe 83, the second valve 821 is opened to pass through the filter 7 to flow the liquid ammonia through the second pipe 82. To pass.

The liquid ammonia supplied through the second pipe 82 and supplied to the third pipe 83 is introduced into the high boiling point impurity adsorption unit 3. The high boiling point impurity adsorption part 3 adsorbs and removes the high boiling point impurity higher than ammonia by the adsorbent which consists of liquid ammonia derived from the oil adsorption tower 2 and passed through the filter 7 with a high boiling point than ammonia. . In this embodiment, the high boiling point impurity adsorption part 3 is comprised including the 1st adsorption tower 31, the 2nd adsorption tower 32, the 3rd adsorption tower 33, and the 4th adsorption tower 34 which are some adsorption | suction parts.

The 1st adsorption tower 31 and the 3rd adsorption tower 33 are connected to the 3rd piping 83 in parallel. The third pipe 83 is provided with a third valve 831 and a fourth valve 832 for opening or closing the flow path in the third pipe 83. In the 3rd piping 83, the 3rd valve 831 is arrange | positioned upstream of the 1st adsorption tower 31 (namely, the top part side of the 1st adsorption tower 31), and the 4th valve 832. ) Is disposed upstream of the third adsorption tower 33 (that is, at the top of the top of the third adsorption tower 33). At the time of supplying the liquid ammonia derived from the oil adsorption tower 2 and passing through the filter 7 to the first adsorption tower 31, the third valve 831 is opened and the fourth valve 832 is closed so that the filter ( 7, the liquid ammonia flows through the inside of the third pipe 83 toward the first adsorption tower 31. In addition, the fourth valve 832 is opened and the third valve 831 is closed at the time of supplying the liquid ammonia, which is drawn out from the oil adsorption tower 2 and passed through the filter 7, to the third adsorption tower 33. Liquid ammonia flows through the third pipe 83 from the filter 7 toward the third adsorption tower 33.

Thus, by having the 1st adsorption tower 31 and the 3rd adsorption tower 33 which the high boiling point impurity adsorption part 3 is connected in parallel, the liquid ammonia derived from the oil adsorption tower 2 and passing through the filter 7 was carried out. Can be introduced in a distinct state with respect to the first adsorption tower 31 and the third adsorption tower 33 respectively connected in parallel, so that, for example, the third adsorption tower which has been used while being adsorbed and removed from the first adsorption tower 31 is completed. At 33, the used third adsorption tower 33 can be regenerated so that the adsorption removal operation can be performed again.

The second adsorption tower 32 is connected in series with the first adsorption tower 31 via a fourth pipe 84. That is, in the 4th piping 84, one end is connected to the tower bottom of the 1st adsorption tower 31, and the other end is connected to the tower top of the 2nd adsorption tower 32. As shown in FIG. As a result, the liquid ammonia derived from the oil adsorption tower 2 and passing through the filter 7 and introduced into the first adsorption tower 31 flows through the fourth pipe 84 and is introduced into the second adsorption tower 32. do. Thus, by having the 1st adsorption tower 31 and the 2nd adsorption tower 32 which the high boiling point impurity adsorption | suction part 3 is connected in series, the liquid ammonia derived from the oil adsorption tower 2 and having passed through the filter 7 was carried out. Since the high boiling point impurities included in the first adsorption tower 31 and the second adsorption tower 32 can be removed by adsorption, the adsorption removal ability for the high boiling point impurities can be improved.

The liquid ammonia derived from the second adsorption tower 32 flows through the fifth pipe 85 and is supplied to the tenth pipe 90 connected to the vaporizer 5.

The fifth pipe 85 is provided with a fifth valve 851 and a sixth valve 852 which open or close the flow path in the fifth pipe 85. In the fifth piping 85, the fifth valve 851 is disposed upstream of the ammonia flow passage direction (ie, the second adsorption tower 32 side), and the sixth valve 852 is downstream of the ammonia flow passage direction. It is arrange | positioned at the side (that is, the 10th piping 90 side). When the liquid ammonia derived from the second adsorption tower 32 is supplied to the tenth pipe 90, the fifth valve 851 and the sixth valve 852 are opened to open the tenth pipe from the second adsorption tower 32. Liquid ammonia flows through the fifth pipe 85 toward 90.

In addition, in the ammonia purification system 100 of this embodiment, the 8th piping branched from the 5th piping 85 between the 5th valve 851 and the 6th valve 852, and connected to the analysis part 4; 88 is installed. The eighth pipe 88 is provided with a ninth valve 881 for opening or closing the flow path in the eighth pipe 88. The ninth valve 881 is always opened when liquid ammonia, which is derived from the oil adsorption tower 2 and passed through the filter 7, is introduced into the first adsorption tower 31 and the second adsorption tower 32, and is required for analysis. A very small amount of ammonia flows through the eighth pipe 88 toward the analyzer 4.

The fourth adsorption tower 34 is connected in series with the third adsorption tower 33 through the sixth pipe 86. That is, in the 6th piping 86, one end is connected to the tower bottom part of the 3rd adsorption tower 33, and the other end is connected to the tower top of the 4th adsorption tower 34. As shown in FIG. As a result, the liquid ammonia derived from the oil adsorption tower 2 and passing through the filter 7 and introduced into the third adsorption tower 33 flows through the sixth pipe 86 and is introduced into the fourth adsorption tower 34. do. Thus, by having the 3rd adsorption tower 33 and the 4th adsorption tower 34 which the high boiling-point impurity adsorption part 3 is connected in series, it is derived from the oil adsorption tower 2, and the liquid ammonia which passed through the filter 7 was carried out. Since the high boiling point impurities included in the third adsorption tower 33 and the fourth adsorption tower 34 may be adsorbed and removed, the adsorption and removal ability for the high boiling point impurities may be improved.

The liquid ammonia derived from the fourth adsorption tower 34 flows through the seventh pipe 87 and is supplied to the tenth pipe 90 connected to the vaporizer 5.

The seventh pipe 87 is provided with a seventh valve 871 and an eighth valve 872 for opening or closing the flow path in the seventh pipe 87. In the seventh pipe 87, the seventh valve 871 is disposed upstream of the ammonia flow passage direction (that is, the fourth adsorption tower 34 side), and the eighth valve 872 is downstream of the ammonia flow passage direction. It is arrange | positioned at the side (that is, the 10th piping 90 side). When the liquid ammonia derived from the fourth adsorption tower 34 is supplied to the tenth pipe 90, the seventh valve 871 and the eighth valve 872 are opened to open the tenth pipe from the fourth adsorption tower 34. Liquid ammonia flows through the seventh pipe 87 toward the 90.

In the ammonia purification system 100 of the present embodiment, the ninth pipe is branched from the seventh pipe 87 between the seventh valve 871 and the eighth valve 872 and connected to the analysis unit 4. 89 is provided. The ninth pipe 89 is provided with a tenth valve 891 for opening or closing the flow path in the ninth pipe 89. The tenth valve 891 is always opened when the liquid ammonia derived from the oil adsorption tower 2 and passed through the filter 7 is introduced into the third adsorption tower 33 and the fourth adsorption tower 34 and is required for analysis. A very small amount of ammonia flows through the ninth pipe 89 toward the analyzer 4.

In addition, in this embodiment, the 1st adsorption tower 31 is the 1st adsorption | suction area | region 311 filled with MS-3A (porous synthetic zeolite with a pore diameter of 3 kPa) as synthetic zeolite, and MS-13X (pore diameter 9 kPa as synthetic zeolite). Porous synthetic zeolite) has a second adsorption region 312 filled therein. In the 1st adsorption | suction tower 31, the 1st adsorption | suction area | region 311 and the 2nd adsorption | suction area | region 312 are connected in series, the 1st adsorption | suction area | region 311 is arrange | positioned at the tower top side, and the 2nd adsorption | suction area | region 312 is ) Is arranged at the bottom of the tower.

In addition, the 2nd adsorption tower 32, the 3rd adsorption tower 33, and the 4th adsorption tower 34 are comprised similarly to the 1st adsorption tower 31, respectively. Specifically, in the second adsorption tower 32, the first adsorption region 321 filled with MS-3A is disposed on the top of the tower, and the second adsorption region 322 filled with MS-13X is disposed on the bottom of the tower. It is. In the 3rd adsorption tower 33, the 1st adsorption | suction area | region 331 filled with MS-3A is arrange | positioned at the tower top side, and the 2nd adsorption | suction area | region 332 filled with MS-13X is arrange | positioned at the tower bottom side. In the fourth adsorption tower 34, the first adsorption region 341 filled with MS-3A is disposed at the top of the tower, and the second adsorption region 342 filled with MS-13X is disposed at the bottom of the tower.

MS-3A of synthetic zeolites is an adsorbent with excellent adsorption capacity for water, and MS-13X is an adsorbent with excellent adsorption capacity for water and hydrocarbons. The first adsorption tower 31, the second adsorption tower 32, the third adsorption tower 33 and the first adsorption zone having the first adsorption region filled with MS-3A and the second adsorption region filled with MS-13X having such adsorption capacity. By using the four adsorption tower 34, high boiling point impurities such as water, higher hydrocarbons, etc. contained in the liquid ammonia derived from the oil adsorption tower 2 and passing through the filter 7 can be efficiently removed.

The adsorbent composed of synthetic zeolites such as MS-3A and MS-13X used in the present embodiment can be regenerated by removing impurities (water and hydrocarbons) adsorbed by any one of heating, reduced pressure, heating and reduced pressure. For example, when removing impurities adsorbed to the adsorbent by heat treatment, the heating may be performed at a temperature of 200 to 350 ° C.

In the ammonia purification system 100 of this embodiment, the temperature of the 1st adsorption tower 31, the 2nd adsorption tower 32, the 3rd adsorption tower 33, and the 4th adsorption tower 34 is controlled to 0-60 degreeC, The pressure is controlled to 0.1 to 1.0 MPa. When the temperature of the first adsorption tower 31, the second adsorption tower 32, the third adsorption tower 33 and the fourth adsorption tower 34 is less than 0 ° C., cooling to remove the heat of adsorption generated during the adsorption removal of impurities is performed. It becomes necessary and there exists a possibility that energy efficiency may fall. If the temperatures of the first adsorption tower 31, the second adsorption tower 32, the third adsorption tower 33 and the fourth adsorption tower 34 exceed 60 ° C., the adsorption capacity of impurities by the adsorbent may decrease. In addition, when the pressure of the first adsorption tower 31, the second adsorption tower 32, the third adsorption tower 33, and the fourth adsorption tower 34 is less than 0.1 MPa, the adsorption capacity of impurities by the adsorbent may decrease. . When the pressure of the first adsorption tower 31, the second adsorption tower 32, the third adsorption tower 33 and the fourth adsorption tower 34 exceeds 1.0 MPa, a large amount of energy is required to maintain the constant pressure. There exists a possibility that efficiency may fall.

Moreover, the linear velocity (linear velocity) in the 1st adsorption tower 31, the 2nd adsorption tower 32, the 3rd adsorption tower 33, and the 4th adsorption tower 34 is a liquid ammonia per unit time. , 32, 33, 34 is preferably in the range of 0.01 to 0.5 m / sec, which is obtained by converting the amount supplied to NTP into a gas volume and dividing the air column cross-sectional area of each adsorption tower (31, 32, 33, 34). Do. If the linear velocity is less than 0.01 m / sec, it is not preferable because the adsorption removal of impurities takes a long time. If the linear velocity exceeds 0.5 m / sec, the adsorption heat generated during the adsorption removal of impurities is sufficiently removed. There is a fear that the adsorption capacity of impurities by the adsorbent may be lowered.

Liquid ammonia derived from the second adsorption tower 32 and flowing through the eighth pipe 88, or liquid ammonia derived from the fourth adsorption tower 34 and flowing through the ninth pipe 89 is analyzed. 4) is introduced.

The analyzing unit 4 analyzes the concentration of impurities contained in the liquid ammonia derived from the second adsorption tower 32 or the fourth adsorption tower 34. In this embodiment, the analyzer 4 is a gas chromatography analyzer (GC-PDD: pulse discharge detector). As a gas chromatographic analyzer, GC-4000 (made by GE Science Co., Ltd.) is mentioned, for example. In the present embodiment, the methane concentration and the oxygen concentration are analyzed by the analyzer 4 with respect to the liquid ammonia derived from the second adsorption tower 32 or the fourth adsorption tower 34. Based on the analysis result by this analysis part 4, the vaporizer | carburetor 5 mentioned later sets the vaporization rate at the time of vaporizing the liquid ammonia derived from the 2nd adsorption tower 32 or the 4th adsorption tower 34. As shown in FIG.

The liquid ammonia derived from the second adsorption tower 32 and supplied to the tenth pipe 90 or the liquid ammonia derived from the fourth adsorption tower 34 and supplied to the tenth pipe 90 is the tenth pipe 90. ) Is passed through and introduced into the vaporizer (5).

The vaporizer 5 vaporizes the liquid ammonia derived from the second adsorption tower 32 or the fourth adsorption tower 34 at a predetermined vaporization rate into a gaseous component and a liquid phase component to separate low boiling point impurities having a lower boiling point than ammonia. Separation is carried out to obtain purified ammonia as a liquid component.

In this embodiment, the vaporizer | carburetor 5 has the vaporization rate of 5-20 volume% of liquid ammonia derived from the 2nd adsorption tower 32 or the 4th adsorption tower 34 based on the analysis result by the analysis part 4. Vaporize and separate into gaseous and liquid components. In this case, 5-20 volume% of the liquid ammonia derived from the 2nd adsorption tower 32 or the 4th adsorption tower 34 becomes a gaseous component, and 80-95 volume% becomes a liquid component.

Specifically, the vaporizer 5 sets the vaporization rate to 5% by volume when the analysis result of the analyzer 4 indicates that the concentration of at least one of methane and oxygen is less than 30 ppb, and at least one of methane and oxygen. If the concentration of is 30ppb or more and less than 50ppb, the vaporization rate is set to 10% by volume, and if the concentration of at least one of methane and oxygen is 50ppb or more and less than 100ppb, the vaporization rate is set to 15% by volume and at least of methane and oxygen If either concentration is 100 ppb or more, the vaporization rate is set to 20% by volume.

In the ammonia purification system 100 of this embodiment, the oil vapor is adsorbed and removed by the oil adsorption tower 2, and high boiling point impurities, such as moisture and a higher-order hydrocarbon, are adsorbed by the high boiling point impurity adsorption | suction part 3. The liquid ammonia after removal is vaporized at a predetermined vaporization rate and separated into a gaseous phase component and a liquid phase component, so that low boiling points such as low-boiling gases such as hydrogen, nitrogen, oxygen, argon and carbon monoxide, and lower hydrocarbons such as methane, ethane and propane Impurities can be separated and removed as a gas phase component to obtain purified liquid ammonia as a liquid component. Therefore, in the ammonia purification system 100 of the present embodiment, ammonia can be purified by a simplified method without distillation with reflux as in the prior art, and ammonia can be efficiently reduced by suppressing energy consumption. It can be purified.

The vaporization conditions in the vaporizer 5 are not limited as long as the liquid ammonia derived from the second adsorption tower 32 or the fourth adsorption tower 34 is vaporized at a predetermined vaporization rate. Set the time appropriately. In this embodiment, the vaporizer | carburetor 5 is comprised so that vaporization of the liquid ammonia derived from the 2nd adsorption tower 32 or the 4th adsorption tower 34 may be carried out at -50-30 degreeC, and it isolate | separates into a gaseous-phase component and a liquid phase component. desirable. As a result, liquid ammonia after the adsorption and removal of oil and high-boiling impurities can be efficiently vaporized to obtain liquid ammonia from which the low-boiling impurities are separated and removed, and the purity of the liquid ammonia can be increased. If the temperature at the time of vaporization with respect to the liquid ammonia in the vaporizer | carburetor 5 is less than -50 degreeC, since much energy is required for cooling, it is unpreferable. It is not preferable because the impurity concentration contained is high.

Further, the vaporizer 5 is preferably configured to vaporize the liquid ammonia derived from the second adsorption tower 32 or the fourth adsorption tower 34 under a pressure of 0.1 to 1.0 MPa to separate the gas phase component and the liquid phase component. When the pressure at the time of vaporization with respect to the liquid ammonia in the vaporizer | carburetor 5 is less than 0.1 Mpa, since the temperature which vaporizes ammonia becomes low, it is unpreferable because much energy is required for cooling, and when it exceeds 1.0 Mpa, Since the temperature which vaporizes ammonia becomes high, the impurity concentration contained in the liquid ammonia obtained as a liquid component becomes high, and it is unpreferable.

The vaporizer 5 is connected to an eleventh pipe 91 provided with an eleventh valve 911 and a twelfth pipe 92 provided with a twelfth valve 921. In addition, a twelfth pipe 92 is connected between the vaporizer 5 and the recovery tank 6.

In the vaporizer 5, the low boiling point impurity separated and removed from the ammonia as the gaseous component flows through the eleventh pipe 91 while the eleventh valve 911 is opened, and is discharged out of the system. In addition, the liquid ammonia obtained as a liquid component in the vaporizer | carburetor 5 flows through the 12th piping 92, and is supplied to the collection tank 6 in the state which the 12th valve 921 opened.

The recovery tank 6 stores the liquid ammonia obtained as the liquid component in the vaporizer 5. It is preferable that the temperature and the pressure be controlled under constant conditions so that the recovery tank 6 can be stored as liquid ammonia.

2 is a diagram illustrating a configuration of the ammonia purification system 200 according to the second embodiment of the present invention. The ammonia purification system 200 of this embodiment is similar to the ammonia purification system 100 mentioned above, and attaches | subjects the same code | symbol about the corresponding part, and abbreviate | omits description. The ammonia purification system 200 is similar to the ammonia purification system 100 except that the structure of the high boiling point impurity adsorption part 201 differs from the structure of the high boiling point impurity adsorption part 3 mentioned above.

The high boiling point impurity adsorption part 201 provided in the ammonia purification system 200 synthesize | combines the high boiling point impurity higher than ammonia contained in the liquid ammonia derived from the oil absorption tower 2 and passing through the filter 7. It adsorbs and removes with the adsorbent which consists of a zeolite. In this embodiment, the high boiling point impurity adsorption part 201 is comprised including the 1st adsorption tower 2011, the 2nd adsorption tower 2012, and the 3rd adsorption tower 2013 which are some adsorption | suction parts.

The 1st adsorption tower 2011, the 2nd adsorption tower 2012, and the 3rd adsorption tower 2013 are comprised similarly to the 1st adsorption tower 31 mentioned above. Specifically, in the first adsorption tower 2011, the first adsorption region 20111 filled with MS-3A is disposed on the top side, and the second adsorption region 20112 filled with MS-13X is disposed on the bottom side of the tower. It is. In the 2nd adsorption tower 2012, the 1st adsorption | suction area 20121 filled with MS-3A is arrange | positioned at the tower top side, and the 2nd adsorption | suction area 20122 filled with MS-13X is arrange | positioned at the tower bottom side. In the 3rd adsorption tower 2013, the 1st adsorption area 20131 filled with MS-3A is arrange | positioned at the tower top side, and the 2nd adsorption area 20132 filled with MS-13X is arrange | positioned at the tower bottom side.

In addition, in the ammonia purification system 200 of this embodiment, the 1st adsorption tower 2011, the 2nd adsorption tower 2012, and the 3rd adsorption tower 2013 are controlled to 0-60 degreeC, and the pressure is 0.1-1.0. It is controlled by MPa. If the temperature of the first adsorption tower 2011, the second adsorption tower 2012, and the third adsorption tower 2013 is less than 0 ° C, cooling to remove the heat of adsorption generated at the time of the adsorption removal of impurities is required, resulting in lower energy efficiency. There is a concern. When the temperature of the first adsorption tower 2011, the second adsorption tower 2012, and the third adsorption tower 2013 exceeds 60 ° C., there is a concern that the adsorption capacity of impurities by the adsorbent may decrease. Moreover, when the pressure of the 1st adsorption tower 2011, the 2nd adsorption tower 2012, and the 3rd adsorption tower 2013 is less than 0.1 Mpa, there exists a possibility that the adsorption capacity of the impurity by an adsorbent may fall. When the pressure of the first adsorption tower 2011, the second adsorption tower 2012, and the third adsorption tower 2013 exceeds 1.0 MPa, a large amount of energy is required to maintain the constant pressure, which may lower energy efficiency. .

In addition, the linear velocity (linear velocity) in the first adsorption tower 2011, the second adsorption tower 2012, and the third adsorption tower 2013 supplies liquid ammonia to each adsorption tower 2011, 2012, 2013 per unit time. It is preferable that the range of the value calculated | required by converting the quantity to convert into the gas volume in NTP, and dividing | segmenting by the air column cross-sectional area of each adsorption tower (2011, 2012, 2013) is 0.01-0.5 m / sec. If the linear velocity is less than 0.01 m / sec, it is not preferable because the adsorption removal of impurities takes a long time. If the linear velocity exceeds 0.5 m / sec, the adsorption heat generated during the adsorption removal of impurities is sufficiently removed. There is a fear that the adsorption capacity of impurities by the adsorbent may be lowered.

In the present embodiment, the thirteenth pipe 202 branched from the third pipe 83 to the third pipe 83 through which the liquid ammonia passed from the oil adsorption tower 2 and passed through the filter 7 flows. And the fourteenth pipe 203 and the fifteenth pipe 204 are connected.

The thirteenth pipe 202 branches from the third pipe 83 and is connected to the tower top of the first adsorption tower 2011. A thirteenth valve 2021 is provided in the thirteenth pipe 202 to open or close the flow path in the thirteenth pipe 202. The 14th piping 203 branches off from the 3rd piping 83, and is connected to the tower top of the 2nd adsorption tower 2012. As shown in FIG. The fourteenth valve 2031 is provided in the fourteenth pipe 203 to open or close the flow path in the fourteenth pipe 203. The fifteenth pipe 204 is branched from the third pipe 83 and connected to the tower top of the third adsorption tower 2013. The fifteenth valve 204 is provided in the fifteenth pipe 204 to open or close the flow path in the fifteenth pipe 204.

Further, a sixteenth pipe 205 through which liquid ammonia derived from the first adsorption tower 2011 flows is connected to the bottom of the tower of the first adsorption tower 2011. The sixteenth pipe 205 is provided with a sixteenth valve 2051 for opening or closing the flow path in the sixteenth pipe 205. The seventeenth pipe 206 through which the liquid ammonia derived from the second adsorption tower 2012 flows is connected to the bottom of the column of the second adsorption tower 2012. The seventeenth pipe 206 is provided with a seventeenth valve 2061 for opening or closing the flow path in the seventeenth pipe 206. An eighteenth pipe 207 through which liquid ammonia derived from the third adsorption tower 2013 flows is connected to the bottom of the column of the third adsorption tower 2013. An eighteenth valve 2071 is provided in the eighteenth pipe 207 to open or close the flow path in the eighteenth pipe 207.

In addition, a nineteenth pipe 208 branched from the sixteenth pipe 205 is connected to the sixteenth pipe 205. The nineteenth pipe 208 is branched from the sixteenth pipe 205 and connected to the fourteenth pipe 203 to introduce the liquid ammonia derived from the first adsorption tower 2011 into the second adsorption tower 2012. It is a flow path. The nineteenth pipe 208 is provided with a nineteenth valve 2021 for opening or closing the flow path in the nineteenth pipe 208. The twentieth pipe 209 branched from the nineteenth pipe 208 is connected to the nineteenth pipe 208. The twentieth pipe 209 branches from the nineteenth pipe 208 and is connected to the fifteenth pipe 204 to introduce the liquid ammonia derived from the first adsorption tower 2011 into the third adsorption tower 2013. It is a flow path. The twentieth pipe 209 is provided with a twentieth valve 2091 for opening or closing the flow path in the twentieth pipe 209.

The twenty-first pipe 210 and the twenty-second pipe 211 branched from the seventeenth pipe 206 are connected to the seventeenth pipe 206. The twenty-first pipe 210 is branched from the seventeenth pipe 206 and connected to the thirteenth pipe 202, and a flow path for introducing liquid ammonia derived from the second adsorption tower 2012 into the first adsorption tower 2011. Becomes The twenty-first pipe 210 is provided with a twenty-first valve 2101 for opening or closing a flow path in the twenty-first pipe 210. The twenty-second pipe 211 is branched from the seventeenth pipe 206 and connected to the fifteenth pipe 204, and a flow path for introducing liquid ammonia derived from the second adsorption tower 2012 into the third adsorption tower 2013. Becomes The twenty-second pipe 211 is provided with a twenty-second valve 2111 for opening or closing a flow path in the twenty-second pipe 211.

In addition, a twenty-third pipe 212 branched from the eighteenth pipe 207 is connected to the eighteenth pipe 207. The twenty-third pipe 212 is branched from the eighteenth pipe 207 and connected to the thirteenth pipe 202 to introduce the liquid ammonia derived from the third adsorption tower 2013 into the first adsorption tower 2011. It is a flow path. The twenty-third pipe 212 is provided with a twenty-third valve 2121 for opening or closing a flow path in the twenty-third pipe 212. The twenty-fourth pipe 213 branched from the twenty-third pipe 212 is connected to the twenty-third pipe 212. The twenty-fourth pipe 213 is branched from the twenty-third pipe 212 and connected to the fourteenth pipe 203 to introduce the liquid ammonia derived from the third adsorption tower 2013 into the second adsorption tower 2012. It is a flow path. The twenty-fourth pipe 213 is provided with a twenty-fourth valve 2131 for opening or closing the flow path in the twenty-fourth pipe 213.

In addition, in the sixteenth pipe 205, the seventeenth pipe 206, and the eighteenth pipe 207, a twenty-fifth pipe 214 is connected to an end portion downstream of the liquid ammonia flow direction. The 25th pipe 214 is supplied with liquid ammonia derived from any one of the first adsorption tower 2011, the second adsorption tower 2012, and the third adsorption tower 2013. The twenty-fifth pipe 214 is branched from the twenty-fifth pipe 214 to the eighth pipe 88 connected to the analyzer 4, and branched from the twenty-fifth pipe 214 to the vaporizer 5. The tenth pipe 90 is installed.

In the ammonia purification system 200 comprised as mentioned above, there exist the following six connection patterns with respect to the connection of the 1st adsorption tower 2011, the 2nd adsorption tower 2012, and the 3rd adsorption tower 2013. As shown in FIG.

The first connection pattern is a connection pattern through which the liquid ammonia, which is derived from the oil absorption tower 2 and passed through the filter 7, is passed in the order of the first adsorption tower 2011 and the second adsorption tower 2012. In the first connection pattern, the thirteenth valve 2021, the seventeenth valve 2061, and the nineteenth valve 2081 are opened, and the fourteenth valve 2031, the fifteenth valve 2041, the sixteenth valve 2051, The eighteenth valve 2071, the twentieth valve 2091, the twenty-first valve 2101, the twenty-second valve 2111, the twenty-third valve 2121, and the twenty-fourth valve 2131 are closed. As a result, the liquid ammonia derived from the oil adsorption tower 2 and passing through the filter 7 flows through the thirteenth pipe 202 and is introduced into the first adsorption tower 2011, and from the first adsorption tower 2011. The derived liquid ammonia flows through the sixteenth pipe 205 and the nineteenth pipe 208, and is introduced into the second adsorption tower 2012. The liquid ammonia derived from the second adsorption tower 2012 is the seventeenth pipe ( It flows through 206 and is supplied to the 25th piping 214, and liquid ammonia is introduce | transduced into the analysis part 4 and the vaporizer | carburetor 5 from this 25th piping 214. In such a first connection pattern, the high boiling point impurities contained in the liquid ammonia can be adsorbed and removed by the first adsorption tower 2011 and the second adsorption tower 2012, thereby improving the adsorption removal ability for the high boiling point impurities. In addition, since the adsorption removal operation | movement in the 3rd adsorption tower 2013 is not performed in a 1st connection pattern, this 3rd adsorption tower 2013 can be regenerated.

The second connection pattern is a connection pattern through which the liquid ammonia derived from the oil adsorption tower 2 and passed through the filter 7 is passed in the order of the first adsorption tower 2011 and the third adsorption tower 2013. In the second connection pattern, the thirteenth valve 2021, the eighteenth valve 2071, and the twentieth valve 2091 are opened, and the fourteenth valve 2031, the fifteenth valve 2041, the sixteenth valve 2051, The seventeenth valve 2061, the nineteenth valve 2021, the twenty-first valve 2101, the twenty-second valve 2111, the twenty-third valve 2121, and the twenty-fourth valve 2131 are closed. As a result, the liquid ammonia derived from the oil adsorption tower 2 and passing through the filter 7 flows through the thirteenth pipe 202 and is introduced into the first adsorption tower 2011, and from the first adsorption tower 2011. The derived liquid ammonia flows through the sixteenth pipe 205, the nineteenth pipe 208, and the twentieth pipe 209 to be introduced into the third adsorption tower 2013, and the liquid phase derived from the third adsorption tower 2013. Of the ammonia flows through the eighteenth pipe 207 and is supplied to the twenty-fifth pipe 214, and the liquid ammonia is introduced into the analyzer 4 and the vaporizer 5 from the twenty-fifth pipe 214. In the second connection pattern, since the high boiling point impurities included in the liquid ammonia can be removed by the first adsorption tower 2011 and the third adsorption tower 2013, the adsorption removal ability for the high boiling point impurities can be improved. In addition, since the adsorption removal operation | movement in the 2nd adsorption tower 2012 is not performed in a 2nd connection pattern, this 2nd adsorption tower 2012 can be regenerated.

The third connection pattern is a connection pattern for passing the liquid ammonia, which is derived from the oil absorption tower 2 and passed through the filter 7, in the order of the second adsorption tower 2012 and the first adsorption tower 2011. In the third connection pattern, the fourteenth valve 2031, the sixteenth valve 2051, and the twenty-first valve 2101 are opened, and the thirteenth valve 2021, the fifteenth valve 2041, the seventeenth valve 2061, The eighteenth valve 2071, the nineteenth valve 2021, the twentieth valve 2091, the twenty-second valve 2111, the twenty-third valve 2121, and the twenty-fourth valve 2131 are closed. As a result, the liquid ammonia derived from the oil adsorption tower 2 and having passed through the filter 7 flows through the fourteenth pipe 203 and is introduced into the second adsorption tower 2012, and from the second adsorption tower 2012. The derived liquid ammonia flows through the seventeenth pipe 206 and the twenty-first pipe 210 to be introduced into the first adsorption tower 2011, and the liquid ammonia derived from the first adsorption tower 2011 is connected to the sixteenth pipe ( It flows through 205 and is supplied to the 25th piping 214, and liquid ammonia is introduce | transduced into the analysis part 4 and the vaporizer | carburetor 5 from this 25th piping 214. In the third connection pattern, since the high boiling point impurities contained in the liquid ammonia can be removed by the first adsorption tower 2011 and the second adsorption tower 2012, the adsorption removal ability to the high boiling point impurities can be improved. In addition, since the adsorption removal operation | movement in the 3rd adsorption tower 2013 is not performed in a 3rd connection pattern, this 3rd adsorption tower 2013 can be regenerated.

The fourth connection pattern is a connection pattern for passing the liquid ammonia, which is derived from the oil absorption tower 2 and passed through the filter 7, in the order of the second adsorption tower 2012 and the third adsorption tower 2013. In the fourth connection pattern, the fourteenth valve 2031, the eighteenth valve 2071, and the twenty-second valve 2111 are opened, and the thirteenth valve 2021, the fifteenth valve 2041, the sixteenth valve 2051, The seventeenth valve 2061, the nineteenth valve 2021, the twentieth valve 2091, the twenty-first valve 2101, the twenty-third valve 2121, and the twenty-fourth valve 2131 are closed. As a result, the liquid ammonia derived from the oil adsorption tower 2 and having passed through the filter 7 flows through the fourteenth pipe 203 and is introduced into the second adsorption tower 2012, and from the second adsorption tower 2012. The derived liquid ammonia flows through the seventeenth pipe 206 and the twenty-second pipe 211 to be introduced into the third adsorption tower 2013, and the liquid ammonia derived from the third adsorption tower 2013 is transferred to the eighteenth pipe ( 207 flows through and is supplied to the 25th piping 214, and liquid ammonia is introduce | transduced into the analysis part 4 and the vaporizer | carburetor 5 from this 25th piping 214. In the fourth connection pattern, since the high boiling point impurities contained in the liquid ammonia can be removed by the second adsorption tower 2012 and the third adsorption tower 2013, the adsorption removal ability to the high boiling point impurities can be improved. In addition, since the adsorption removal operation | movement in the 1st adsorption tower 2011 is not performed in a 4th connection pattern, this 1st adsorption tower 2011 can be regenerated.

The 5th connection pattern is the connection pattern which passes the liquid ammonia which passed out from the oil absorption tower 2 and passed the filter 7 in order of the 3rd adsorption tower 2013 and the 1st adsorption tower 2011. FIG. In the fifth connection pattern, the fifteenth valve 2041, the sixteenth valve 2051, and the twenty-third valve 2121 are opened, and the thirteenth valve 2021, the fourteenth valve 2031, the seventeenth valve 2061, The eighteenth valve 2071, the nineteenth valve 2021, the twentieth valve 2091, the twenty-first valve 2101, the twenty-second valve 2111, and the twenty-fourth valve 2131 are closed. As a result, the liquid ammonia derived from the oil adsorption tower 2 and passing through the filter 7 flows through the fifteenth pipe 204 to be introduced into the third adsorption tower 2013, and from the third adsorption tower 2013. The extracted liquid ammonia flows through the eighteenth pipe 207 and the twenty-third pipe 212 and is introduced into the first adsorption tower 2011. The liquid ammonia derived from the first adsorption tower 2011 is the sixteenth pipe ( It flows through 205 and is supplied to the 25th piping 214, and liquid ammonia is introduce | transduced into the analysis part 4 and the vaporizer | carburetor 5 from this 25th piping 214. In the fifth connection pattern, since the high boiling point impurities included in the liquid ammonia can be removed by the first adsorption tower 2011 and the third adsorption tower 2013, the adsorption removal ability for the high boiling point impurities can be improved. In addition, since the adsorption removal operation | movement in the 2nd adsorption tower 2012 is not performed in a 5th connection pattern, this 2nd adsorption tower 2012 can be regenerated.

The 6th connection pattern is the connection pattern which passes the liquid ammonia which passed out from the oil absorption tower 2 and passed the filter 7 in order of the 3rd adsorption tower 2013 and the 2nd adsorption tower 2012. As shown in FIG. In the sixth connection pattern, the fifteenth valve 2041, the seventeenth valve 2061, and the twenty-fourth valve 2131 are opened, and the thirteenth valve 2021, the fourteenth valve 2031, the sixteenth valve 2051, The eighteenth valve 2071, the nineteenth valve 2021, the twentieth valve 2091, the twenty-first valve 2101, the twenty-second valve 2111, and the twenty-third valve 2121 are closed. As a result, the liquid ammonia derived from the oil adsorption tower 2 and passing through the filter 7 flows through the fifteenth pipe 204 to be introduced into the third adsorption tower 2013, and from the third adsorption tower 2013. The extracted liquid ammonia flows through the eighteenth pipe 207, the twenty-third pipe 212, and the twenty-fourth pipe 213, and is introduced into the second adsorption tower 2012, and the liquid phase derived from the second adsorption tower 2012. Of the ammonia flows through the seventeenth pipe 206 and is supplied to the twenty-fifth pipe 214, and the liquid ammonia is introduced into the analyzer 4 and the vaporizer 5 from the twenty-fifth pipe 214. In the sixth connection pattern, since the high boiling point impurities contained in the liquid ammonia can be removed by the second adsorption tower 2012 and the third adsorption tower 2013, the adsorption removal ability for the high boiling point impurities can be improved. In addition, in the 6th connection pattern, since the adsorption removal operation | movement in the 1st adsorption tower 2011 is not performed, this 1st adsorption tower 2011 can be regenerated.

The present invention may be embodied in other forms without departing from the spirit or essential characteristics thereof. Accordingly, the above-described embodiments are merely examples in all respects, and the scope of the present invention is shown in the claims, and is not limited in any way to the specification text. In addition, all the variations and changes which belong to a claim are within the scope of the present invention.

1: storage tank 2: oil absorption tower
3: high boiling point impurity adsorption part 4: analysis part
5: carburetor 6: recovery tank
31, 2011: First adsorption tower 32, 2012: Second adsorption tower
33, 2013: third adsorption tower 34: fourth adsorption tower
100, 200: ammonia purification system
311, 321, 331, 341, 20111, 20121, 20131: first adsorption zone
312, 322, 332, 342, 20112, 20122, 20132: second adsorption zone

Claims (7)

As an ammonia purification system for purifying crude ammonia containing impurities:
A storage part for storing liquid ammonia,
A first adsorption unit for adsorbing and removing the oil contained in the liquid crude ammonia stored in the storage unit with activated carbon to derive the liquid ammonia;
A second adsorption unit which adsorbs and removes the high boiling point impurity higher than ammonia contained in the liquid ammonia derived from the first adsorption unit by using a synthetic zeolite to derive the liquid ammonia;
The liquid ammonia derived from the second adsorption unit is vaporized at a predetermined vaporization rate and separated into a gas phase component and a liquid component to separate and remove low boiling point impurities having a lower boiling point than ammonia as a gas phase component to obtain purified liquid ammonia as a liquid component. Ammonia purification system comprising a vaporization unit. The method of claim 1,
Further comprising an analysis unit for analyzing the concentration of impurities contained in the liquid ammonia derived from the second adsorption unit,
And said vaporization section sets said predetermined vaporization rate when vaporizing liquid ammonia derived from said second adsorption section based on an analysis result by said analysis section. 3. The method of claim 2,
And said vaporization section sets said predetermined vaporization rate at the time of vaporizing liquid ammonia derived from said second adsorption section to 5 to 20% by volume. The method according to any one of claims 1 to 3,
And said vaporization unit vaporizes liquid ammonia derived from said second adsorption unit at a temperature of -50 to 30 ° C to separate gaseous and liquid components. The method according to any one of claims 1 to 4,
The second adsorption unit has a first adsorption region filled with MS-3A as a synthetic zeolite and a second adsorption region filled with MS-13X as a synthetic zeolite. 6. The method according to any one of claims 1 to 5,
The second adsorption section is a plurality of adsorption sections for adsorbing and removing high boiling point impurities contained in liquid ammonia derived from the first adsorption section, and having a plurality of adsorption sections connected in series or in parallel. . As a method of purifying crude ammonia containing impurities:
A storage process for storing liquid crude ammonia,
A first adsorption step of adsorbing and removing the oil contained in the liquid crude ammonia stored in the storage step with activated carbon;
A second adsorption step of adsorbing and removing a high boiling point impurity having a higher boiling point than that of ammonia by the synthetic zeolite, which is contained in the liquid ammonia in which the oil is adsorbed and removed in the first adsorption step;
In the second adsorption process, the liquid ammonia from which the high boiling point impurities have been adsorbed and removed is vaporized at a predetermined vaporization rate and separated into a gaseous phase component and a liquid phase component. And a vaporization step of obtaining the purified liquid ammonia.

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