JPS643441Y2 - - Google Patents

Description

[Detailed explanation of the invention] (a) Technical field of the invention This invention effectively utilizes the heat obtained from equipment such as chemical processes to collect the overhead vapor obtained from the rectification tower used in the equipment. The present invention relates to an absorption heat pump device that takes out heated fluid at a high temperature level.

(b) Prior art and its problems Conventionally, in equipment used in petroleum refining and other scientific processes, the top vapor of a rectification tower is condensed in a condenser, further cooled in a cooler, and then led to a reflux tank.
A portion of the reflux tank is returned to the rectification column, and a portion is taken out as a distillate.

However, in the above conventional equipment, cooling water (e.g. seawater) supplied to the condenser and cooler
Because the heat obtained from the equipment was disposed of outside the equipment (for example, into the sea), it was customary to waste the heat obtained from the equipment without making any use of it. Therefore,
In recent years, as shown in FIG. 1, it has been proposed to utilize the top steam from a rectification column 1 used in the above-mentioned equipment as a heat source for an absorption heat pump 2. In Figure 1, 3, 4, 5, 6 and 7 are
Respectively, the generator, condenser, evaporator, absorber and solution heat exchanger of the absorption heat pump 2, these devices include a refrigerant liquid pipe 9 with a first refrigerant pump 8;
a refrigerant liquid return pipe 11 having a second refrigerant pump 10;
Concentrated liquid tube 13 and diluted liquid tube 1 with solution pump 12
The generator 3 and evaporator 5 house heat source tubes 15 and 16, respectively, and the condenser 4 and absorber 6 house a cooling tube 17 and a fluid to be heated, respectively. A take-out tube 18 is housed therein. 19 is a reflux tank used in the above equipment;
20 is a tower top steam conduit connecting the top of the rectification column 1 and the heat source tubes 15 and 16; 21 is a tower top steam conduit that connects the top of the rectification column 1 and the heat source tubes 15 and 16; The reflux tank and the heat source tubes 15 and 1 are used as a heat source to separate the refrigerant from the absorption liquid and to vaporize the liquid refrigerant in the evaporator 5, so that the condensed drain is guided to the reflux tank 19.
6 is connected to the drain pipe, 22 is a drain heat recovery device in which the pipe and the concentrated liquid pipe 13 are arranged in a heat exchange relationship, and 23 is a drain heat recovery device for rectifying a part of the drain led to the reflux tank 19. A liquid return pipe 25 with a liquid pump 24 connecting the upper part of the rectification column and the reflux tank 19 so as to return it to the column 1 takes out a part of the drain led to the reflux tank 19 as a distillate. As shown, liquid return pipe 2
A distillate pipe connected to the discharge side of the liquid pump 24 of No. 3, 2
Reference numeral 6 denotes a filtrate pipe connected to the bottom of the rectification column 1, and 27 a stock solution supply pipe that leads the stock solution to the middle part of the rectification column 1. Therefore, the absorption heat pump 2
In the absorber 6, the heat generated when the vaporized refrigerant from the evaporator 5 is absorbed into the absorption liquid (hereinafter referred to as absorption heat) raises the temperature of the fluid in the heated fluid extraction pipe 18 to a temperature higher than the top vapor temperature. The fluid to be heated is taken out.

However, in the absorption heat pump device shown in FIG. 1, the flow of steam and condensate from the rectifying column 1 to the reflux tank 19 is performed by the pressure difference and head difference between the reflux tank and the rectifying column 1. If the condensate flow resistance in the condensate heat recovery device 22 is too large, the condensate will not flow and the rectification column 1 and the absorption heat pump 2 may not work properly. There is a restriction that the heat transfer area cannot be made sufficiently large, and there is also a disadvantage that the heat transfer performance of the drain heat recovery device is not good.

Therefore, in the drain heat recovery device 22, the temperature of the absorbing liquid, that is, the concentrated liquid sent from the generator 3 to the absorber 6 cannot be sufficiently raised, and the absorbed heat is not heated until the temperature corresponds to the saturated vapor pressure of the concentrated liquid. As a result of being consumed in raising the temperature of the liquid, there is a disadvantage that the heat output from the absorber 6 decreases, that is, the amount of heat of the heated fluid taken out from the heated fluid extraction pipe 18 decreases by the sensible heat consumption of the concentrated liquid.

(c) Means to solve the problem In view of the above problems, the present invention is a system in which the top vapor from the rectifier is used as a heating source in the generator and evaporator of an absorption heat pump and becomes a drain. directly into the reflux tank, and
A configuration is adopted in which a part of the drain led to the reflux tank, that is, a distillate discharged from the reflux tank by a liquid pump, is used to raise the temperature of the absorption liquid, that is, the concentrated liquid, sent from the generator of the absorption heat pump to the absorber. This provides an absorption heat pump device that effectively utilizes heat obtained from equipment such as chemical processes and efficiently extracts a fluid to be heated that has a temperature equal to or higher than the top steam temperature.

(d) Embodiment Figure 2 is a diagram showing an embodiment of the present invention.
Components similar to those shown in the figures are given the same reference numbers. In FIG. 2, 22' is a heat recovery device in which the distillate pipe 25 and concentrated liquid pipe 13 are arranged in a heat exchange relationship.

In an absorption heat pump device with such a configuration,
Since the heat recovery device 22' is disposed so that the absorption liquid, that is, the concentrated liquid sent from the generator 3 to the absorber 6 is heated by the distillate discharged by the liquid pump 24, the heat recovery device Since the heat transfer area can be made larger than that of the drain heat recovery device 22 shown in FIG. 1, and the flow state of the distillate becomes turbulent, the heat transfer performance is also good. As a result, the heat of the distillate, that is, the heat obtained from the chemical process, is effectively recovered to the absorption heat pump 2.

Further, the temperature of the distillate discharged from the reflux tank 19 by the liquid pump 24 is the drain temperature, that is, the temperature of the evaporator 5.
By appropriately selecting the heat transfer area of the heat recovery device 22', the temperature of the concentrated liquid sent to the absorber 6 can be adjusted to the same level as the top vapor condensation temperature in the heat source tube 16. In other words, the temperature can be raised close to the saturated temperature corresponding to the saturated vapor pressure of the concentrated liquid in the absorber 6, so most of the absorbed heat spent on heating the concentrated liquid is transferred to the heat recovery device. As a result of being recovered by 22', the amount of heat of the heated fluid obtained from the absorber 6 is increased, and the heat output of the absorption heat pump 2 is improved, that is, the efficiency is improved.

Although not shown, the temperature of the concentrated liquid may be increased by arranging the heat recovery device 22' in a heat exchange relationship with the concentrated liquid pipe 13 and the canned liquid pipe 26. The temperature of the concentrated liquid may be raised by a condensation drain of heat source steam of a reboiler used to boil and evaporate the raw liquid or the liquid at the bottom of the rectification column 1. In addition, when using a hot fluid with a higher temperature than the distillate, such as canned liquid or reboiler drain, the amount of hot fluid flowing through the heat recovery 22' is adjusted with a control valve, etc. to keep the temperature rise of the concentrated liquid to the saturation temperature. It is desirable to do the following.

(e) Effects of the invention As described above, the absorption heat pump device of the invention allows the overhead vapor from the rectification column used in chemical process equipment to flow in parallel to the generator and evaporator of the absorption heat pump. A heat recovery device is installed to raise the temperature of the concentrated liquid of the absorption heat pump using the distillate while discharging a part of the liquid condensed from the tower top vapor, that is, the distillate, with a liquid pump. Because it is,
While making effective use of the heat obtained from the above equipment, it is possible to efficiently take out the heated fluid with a temperature higher than the tower top steam temperature.In addition, since the tower top steam is condensed by the absorption heat pump, it is possible to efficiently extract the heated fluid from the reflux tank. This has practical effects such as eliminating the need for a condenser or cooler for obtaining the liquid and distillate to be returned to the rectification column.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of a circuit system of a conventional absorption heat pump device, and FIG. 2 is a schematic explanatory diagram of a circuit system of an absorption heat pump device showing an embodiment of the present invention. 1... Rectification column, 2... Absorption heat pump, 3...
... Generator, 4... Condenser, 5... Evaporator, 6...
Absorber, 13... concentrated liquid pipe, 15, 16... heat source tube, 19... reflux tank, 20... tower top steam conduit, 2
1... Drain pipe, 24... Liquid pump, 25... Distillate pipe, 22'... Heat recovery device.

Claims (1)

[Scope of utility model registration request] The top vapor from a rectification column used in equipment such as chemical processes is passed through the generator and evaporator of an absorption heat pump in parallel to serve as a heating source for separating the refrigerant from the absorption liquid and vaporizing the liquid refrigerant. After use, an absorption liquid is provided with piping leading to a reflux tank used in the equipment, and the distillate discharged from the reflux tank by a liquid pump is sent from the generator of the absorption heat pump to the absorber. A heat recovery device is installed to raise the temperature of the absorption heat pump, and the heat generated when the vaporized refrigerant from the evaporator is absorbed into the absorption liquid in the absorber of the absorption heat pump is used to extract the fluid to be heated whose temperature is higher than the top vapor temperature. An absorption heat pump device characterized by: