JPS5849883A - Method and device for cooling adsorption tower - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cooling method and apparatus for an adsorption tower constituting a feed air pretreatment system of a nitrogen generator that collects no liquid nitrogen or only a relatively small amount of liquid nitrogen, and particularly relates to an adsorption This invention relates to an adsorption tower cooling method and apparatus suitable for shortening the tower cooling time (JIL switching time).

A conventionally known adsorption tower cooling method and apparatus will be explained with reference to FIG.

- Moisture and carbon dioxide contained in the feed air pressurized to about 8 Kf/dG are adsorbed and removed by adsorbents (not shown) in at least two adsorption towers I, which are installed and used alternately. The raw air from which the moisture content and carbon dioxide have been removed is supplied to the nitrogen generator 2 and separated into product nitrogen and liquid nitrogen.

The separated liquid waste nitrogen is temporarily stored in the condenser (not shown) of the nitrogen generator 2 and then directly extracted as waste nitrogen gas. A part or the entire amount is heated to about 300°C by electric heat or steam in the regenerative heater 1!4 installed in the middle of the pipe 53, and then supplied to the adsorption tower 1 via the pipe 3, and is heated inside the adsorption tower! The moisture and carbon dioxide adsorbed by the adsorbent are removed by the adsorbent and released into the atmosphere.Next, after the regeneration of the adsorbent is completed, the adsorption tower 1 is heated by a regeneration heater 4.
It is cooled from about 300° C. to room temperature by the waste nitrogen gas which is directly extracted from the condenser of the nitrogen generator f2 without being heated and supplied through the pipe 3. Thereafter, the adsorption tower 1 cooled to room temperature is used again to adsorb and remove moisture and carbon dioxide contained in the raw air.

Nine, with the nitrogen generator R2, approximately 10% of the nitrogen gas can be collected in liquid form, but if no or only a relatively small amount of liquid nitrogen is collected, there will be no surplus, and this surplus liquid nitrogen must be cooled. is consumed only to increase the temperature difference between the raw material air and the product nitrogen gas and waste nitrogen gas in the nitrogen generator 2, thereby increasing the enthalpy difference.

When cooling the adsorption tower with such waste nitrogen gas, the temperature of the waste nitrogen gas is relatively high at 10 to 15°C, so the cooling time of the adsorption tower is long, and the switching time is also long. Therefore, since the amount of adsorbent in the adsorption tower increases, the amount of power consumed or the amount of steam in the regeneration heater that heats the waste nitrogen gas used for regenerating the adsorbent increases, and as a result, nitrogen gas is generated. The disadvantage was that the basic unit was large.

The present invention is aimed at eliminating the above-mentioned drawbacks, and is aimed at reducing the temperature of waste nitrogen gas directly extracted from the surplus liquid nitrogen liquefied in the nitrogen generator or liquid high nitrogen through the condenser of the nitrogen generator. An adsorption tower cooling method in which the adsorption tower is cooled with nitrogen gas or waste nitrogen gas that is maintained at a low temperature and gasified, and the waste nitrogen gas is extracted directly from the upper part of the high pressure tower of the nitrogen generator or the condenser and the condenser of the nitrogen generator. The present invention provides a cooling system for an adsorption tower, which is connected to a pipe in which a regeneration heater is installed along the way, and a pipe in which a nitrogen generator, a tank, an evaporator, and a switching valve are installed. .

An embodiment of the present invention will be explained with reference to FIG. Nana, 1st
Devices and the like that are the same as those in the figures are denoted by the same reference numerals and explanations will be omitted.

In Fig. 2, tank 5I evaporation 116. The pipe 8 where the switching valve 7a is installed is connected to the upper part of the high pressure column (not shown) of the nitrogen generator 2 or to the condenser (
(not shown), while the other end of the pipe 8 is connected to the pipe 3. In addition, the regeneration heater 4 of the pipe 3 and the pipe 8
A switching valve 7b is installed in the middle of the connection point. In this case, the waste nitrogen gas is directly extracted from the condenser of the nitrogen generator 2, heated to approximately 300°C in the regeneration heater 4, and adsorbed after heating and regeneration of the adsorbent (not shown) in the adsorption tower 1 by the hazardous nitrogen gas. Cooling of the column I from about 300° C. to room temperature is carried out as follows.

First, the switching valve 7b installed in the pipe 3 is closed, and the liquid nitrogen or liquid high nitrogen extracted from the upper part of the high pressure column or the condenser of the nitrogen generator W12 and stored in the tank 5 is supplied to the evaporator 6. Then, in evaporation step 16, the temperature of the waste nitrogen gas is maintained at a temperature lower than that of the waste nitrogen gas directly extracted from the condenser of the nitrogen generator 12, and the gas is gasified.

Thereafter, the nitrogen gas gasified in the evaporator 6 or the waste nitrogen gas is supplied to the adsorption tower 1 through the pipe 8J and the pipe 3 through the open switching valve 7J1 and the adsorption tower 1 whose temperature is about 300°C.
Cool to room temperature. The adsorption tower l cooled in the room-temperature trench is used again to adsorb and remove the moisture and carbon dioxide contained in the feed air, and then the moisture and carbon dioxide are removed from the adsorbent, i.e., the adsorbent is regenerated as described above. It will be held on.

In this example, the adsorption tower was cooled using excess liquid nitrogen, nitrogen gas gasified from liquid high nitrogen, or waste nitrogen gas. It is also possible to switch and use the discharged - fi - waste nitrogen gas.

In this way, the adsorption tower can be cooled by generating nitrogen f! from excess liquid nitrogen or high liquid nitrogen liquefied by the nitrogen generator. When using nitrogen gas or waste nitrogen gas that has been gasified in an evaporator and maintained at a lower temperature than the temperature of the waste nitrogen gas directly extracted from the condenser in the evaporator, the cooling time of the adsorption tower can be shortened, and the adsorption time can be reduced. The switching time of the column can be shortened and therefore the amount of adsorbent in the adsorption column can be reduced.

As explained above, the present invention maintains a low temperature and gasifies surplus liquid nitrogen liquefied in a nitrogen generator or waste nitrogen gas directly extracted from a condenser of a nitrogen generator from liquid waste nitrogen. By cooling the adsorption tower with nitrogen gas or waste nitrogen gas, the cooling and switching time of the adsorption tower is shortened, and the amount of adsorbent in the adsorption tower is reduced, so the power consumption or steam amount in the regeneration heater is reduced. It has the effect of reducing the nitrogen gas generation unit.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of a conventionally known feed air pretreatment device, and Fig. 2 is a diagram illustrating an embodiment of the present invention. It is a system diagram of an air pretreatment device. 1...Adsorption tower, 2...Nitrogen generator,
3, 8... Piping, 4... Regeneration heater, 5...
... Tank, 6 ... Evaporator, 7a, 71)
・・・・・・Switching benshi 1 illustration T product refusal

Claims (1)

[Claims] 1. Raw material for a nitrogen generator that sprinkles no or only a relatively small amount of liquid nitrogen! In a cooling method for an adsorption tower that constitutes an air pretreatment device and is heated and regenerated by waste nitrogen gas extracted directly from the condenser of the nitrogen generator, the excess liquefied in the nitrogen generator is A method for cooling an adsorption tower, characterized in that the adsorption tower is cooled with nitrogen gas or waste nitrogen gas that is gasified from liquid nitrogen or liquid waste nitrogen and maintained at a temperature lower than that of the waste nitrogen gas. 2. Consists of a raw material all-air pretreatment device for a nitrogen generator that collects no or only a relatively small amount of liquid nitrogen, and waste nitrogen gas extracted directly from the condenser of the nitrogen generator is distributed and In a cooling system for an adsorption tower connected to a pipe in which a regeneration heater is installed, the pipe is connected to the upper part of the high-pressure tower or conduit of the nitrogen generator and the pipe is connected to the tank, evaporator, and switch between the nitrogen generator and the tank. A cooling device for adsorption towers, characterized in that they are connected by pipes equipped with valves.