JPS60175588A - Carbon dioxide recovery apparatus - Google Patents

Abstract

PURPOSE:To perform the self-feeding of carbon dioxide used in preparing potable water, by providing a gas extraction apparatus and a dissolving and absorbing apparatus to the confluent pipe communicated with the gas extraction pipe connected to each condenser in the high temp. stage side of an evaporation type seawater desalting apparatus so as to successively arrange both apparatuses on the downstream side. CONSTITUTION:Evaporators 4 each equipped with a flash box 1, a demister 2 and a condenser 3 are connected in a multi-stage fashion and seawater is introduced into the condenser 3 of each evaporator 4 from one end side thereof and withdrawn from the other end side thereof and, after heated by a main heater, evaporated while sent to the flash box 1 of each evaporator 4 in the other end side thereof. Gas extraction pipings 5 are respectively arranged to the steam sides of the condensers 3 of plural evaporators 4 in the high temp. stage side H being the other end side thereof and met to form a confluent pipe 6 while the ejector 8 connected to a water supply pipe 7 is provided to said confluent pipe 6 and a pipeline 9 is connected to a dissolving tank 10 where carbon dioxide is dissolved and absorbed from non-condensible gas containing carbon dioxide.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a carbon dioxide recovery device for recovering carbon dioxide gas generated from a seawater desalination device.

``Prior Art'' There are various methods for producing fresh water from seawater, such as evaporation methods and decontamination methods.The evaporation method uses a seawater desalination apparatus as shown in FIG. Zunawara, Fludge L Box A
1 evaporator d equipped with a demister b and a condenser C is connected in multiple stages, and seawater is pumped by a pump 9 driven by a steam turbine or the like.
It is sent to the condenser C of the evaporator d on the rear stage side, and then passed to the condenser C of the evaporator d on the front stage side, and then transferred to the main heater e.
The heated seawater is then sent to the flash box a of the evaporator d on the previous stage and exposed to negative pressure to evaporate.The evaporated water vapor passes through the demister b, water droplets are removed, and it condenses. In the vessel C, the water vapor is cooled by the seawater passing through the condenser C and condensed, and distilled water accumulates in the receiving part f.

The heated seawater that has passed through the first stage evaporator d is transferred to the next stage evaporator d.
Distilled water is generated in the same process as described above and collected in the receiving part ``3'', and is sequentially transferred to each of the subsequent evaporators d to generate distilled water in the same way.

Furthermore, a bleed pipe 11 is connected to the condenser C of each stage for discharging non-condensable gas such as nitrogen, oxygen, carbon dioxide, etc., which are components of air dissolved in seawater, into the atmosphere. d
The degree of negative pressure inside the condenser is increased to improve the thermal luminosity and the water vapor is guided to the condenser C to increase the condensation efficiency.

The distilled water thus produced is extracted by a pump or the like through the distilled water pipe i, and is used as drinking water, industrial water, irrigation water, or the like.

However, in order to make the distilled water produced by the seawater desalination equipment potable, it is necessary to increase the hardness of the water, and one way to do this is to dissolve carbon dioxide gas in distilled water and then add calcium carbonate or calcium hydroxide. A method has been used in which a carbon dioxide gas generator is reacted, but this requires the provision of a carbon dioxide gas generating device, and the installation costs and costs are high.

[Purpose of the Invention] The present invention provides self-sufficient carbon dioxide gas used in producing drinking water from distilled water obtained from an evaporative seawater desalination device.
The purpose is to ensure that

[Structure of the Invention] The present invention provides an oil and gas device connected to each condenser on the high-temperature stage side of an evaporative seawater desalination device, and an oil and gas device and a dissolving/absorbing device connected to a confluence pipe that communicates with the oil and gas pipe. By installing the devices in sequence, the carbon dioxide in the carbon dioxide-rich non-condensable gas generated on the high-temperature stage side of the evaporative seawater desalination device is recovered in a solution state, and the carbon dioxide contained in the non-condensable gas is heated. The present invention relates to a carbon dioxide recovery device that can be used to process hot water into drinking water and eliminates the need for carbon dioxide generation equipment.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows a first embodiment of the apparatus of the present invention, in which evaporators 4 equipped with a flash box 1, a demister 2, and a condenser 3 are arranged in series, and each evaporator 4 has a condenser 3. Seawater is introduced from one end side, extracted from the other end side, heated by the main heater, and then transferred to the flash box 1 of the evaporator 4 on the other end side.
The liquid is then sent to the flash box 1 of the evaporator 4 at one end, where it is evaporated.

A bleed pipe 5 is disposed on the steam side of each condenser 3 of the plurality of evaporators 4 on the other end side, that is, on the high temperature stage side H, and the bleed pipes 5 are merged to form a merging pipe 6, A pipe 6 is provided with an ejector 8 connected to a water supply pipe 7, and the ejector 8
A conduit 9 connected to the outlet of the molten FIv pipe 10 is connected to the melt FIv cypress 10 so that carbon dioxide gas can be dissolved and dissolved from the non-condensable gas containing carbon dioxide gas.

In the figure, 11 is a carbon dioxide gas solution supply pipe, 12 is a non-absorbent gas discharge pipe 1j], and although not shown, each evaporator on the low-temperature stage side is connected to each other by a bleed pipe, and the final stage condensation The popular ejector 13 releases 1q of sea urchins.

With the above configuration, the seawater that has been gradually heated inside each evaporator 4 from the low temperature stage side to the high temperature stage side H is further heated by the main heater, and then heated to the first part of the high temperature stage side 1. Sent to flash box 1.

Air components such as nitrogen, oxygen, and carbon dioxide that were dissolved in the heated seawater are easily released by heating.
and a confluence pipe 6 and each bleed pipe 5 by an ejector 8,
Since the inside of the condenser 3 and the evaporator 4 are under negative pressure, the evaporation of water in the heated seawater is promoted, and the release of the dissolved air component is also promoted.

The water vapor and other gas components evaporated in the first evaporator 4 pass through the demister 2, where water droplets are separated, and then reach the condenser 3, where they are cooled by seawater flowing through the condenser 3. The water vapor condenses and accumulates in the receiver, but other gas components such as nitrogen, oxygen, carbon dioxide, etc. are non-condensable and are therefore extracted as gases through the extraction pipe 5.

Next, the seawater from which some of the water has evaporated and a considerable part of the dissolved air components has been removed enters the flash box 1 of the next-stage evaporator 4, where it evaporates in the same manner as described above and releases other gas components. , condensation of water vapor and extraction of non-condensable gases are carried out.

Thereafter, water vapor is condensed and non-condensable gas is extracted until the final stage in the same manner as described above, and distilled water, non-condensable gas and condensed seawater are obtained.

In the above process, the temperature of the seawater in each crush box 1 is highest in the first stage, decreases sequentially, and becomes the lowest in the final stage, and the carbon dioxide gas is extracted at high concentration and with good yield in the high temperature stages 1 to 1. It will be collected.

The non-condensable gas containing a large amount of carbon dioxide gas is sucked by the water passing through the diode 8 and passes through the pipe line 9 and enters the dissolving tank 1o. At this time, most of the carbon dioxide gas, which is relatively easily soluble in water, is dissolved and absorbed, and other non-absorbable gas components are released into the atmosphere from the exhaust gas pipe 12 provided at the top of the melt 1ff10. The solvent for absorbing carbon dioxide gas is not limited to water, and an alkaline solution adjusted to easily absorb carbon dioxide gas (for example, a solution containing calcium hydroxide or the like) may be used.

If the carbonic acid solution thus recovered in a solution state is added to the distilled water pipes from which the distilled water accumulated in the receivers of the respective condensers 3 is extracted, and calcium hydroxide etc. are added in a subsequent step,
Water can be easily softened and can be used as drinking water.

FIG. 3 shows a second embodiment of the device of the present invention, in which the downstream end of the merging pipe 6 is introduced into the barometric condenser 14, and each condenser 3 has a configuration substantially similar to that of the first embodiment. The downstream end of a distilled water branch pipe 17, which is branched from the outlet side of the pump 16 of the distilled water pipe 15 which extracts the distilled water accumulated in the receiver, is introduced into the barometric condenser 14. exhaust pipe 18
A dioctor 19 is provided in the exhaust pipe 18 so that the inside of the barometric condenser 14 can be made negative H, and a drain pipe 2o is connected to the bottom of the barometric condenser 14. This allows the solution in which carbon dioxide gas has been dissolved and absorbed to be discharged into the tank 21.

In the case of this embodiment, the carbon dioxide rich non-condensable gas recovered from the evaporator 4 on the high temperature stage side H and a portion of the distilled water condensed in the evaporator 4 are transferred to the barometric condenser 14.
The carbon dioxide gas is dissolved and absorbed in distilled water, and the solution that has absorbed carbon dioxide gas is transferred from the liquid drain pipe 2o to the tank 2.
At the same time, the non-absorbable gas is exhausted by the ejector 19 to create a negative pressure in the barometric condenser 14, and the non-condensable gas of the carbon dioxide ridge from each condenser 3 is extracted. Do the following.

FIG. 4 shows a third embodiment of the present invention, in which a condenser 22 and a vacuum pump 23 for water vapor condensation are sequentially provided in the downstream side of the confluence pipe 6, and the condenser 22 and vacuum pump 23 are sequentially provided on the downstream side of the confluence pipe 6. The downstream side of the vacuum pump 23 of the pipe 6 is connected to the lower part of the absorption tower 24, and the water supply pipe 25 is connected to the upper part of the absorption tower 24. In the figure, 26 indicates a liquid drain pipe, and 27 indicates a non-absorbable gas diffusion pipe.

In the case of this embodiment, when the carbon dioxide-rich non-condensable gas extracted from the condenser 3 of each evaporator 4 by the vacuum pump 23 passes through the condenser 22, the water vapor that is accompanied to some extent is almost completely removed. After that, the water is fed into the absorption tower 24, and while rising inside the absorption tower 24 from the bottom to the top, the water supply pipe 2
5 is introduced from the upper part of the absorption tower 24 and comes into contact with water flowing downward from above in a countercurrent manner, carbon dioxide gas is dissolved and absorbed by the water, and flows out from the drain pipe 26. - Gases that are difficult to be absorbed by the power water are discharged into the atmosphere from the diffusion pipe 27.

It should be noted that the carbon dioxide absorption device of the present invention is not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

[Effects of the Invention] As described above, according to the carbon dioxide recovery device of the present invention,
The carbon dioxide-rich non-condensable gas generated from the evaporator on the high-temperature stage side is collected, and the carbon dioxide gas is dissolved and absorbed in water or a solution, so that the carbon dioxide gas can be separated from gas components other than carbon dioxide gas. If the recovered carbon dioxide gas dissolving and absorbing solution is used to convert distilled water into drinking water, self-sufficiency of carbon dioxide becomes possible, eliminating the need for carbon dioxide generation equipment that was previously required. In addition, since it can be recovered as a solution, it can be stored, and it exhibits various excellent effects, such as being able to supply carbon dioxide gas even when the seawater desalination equipment is stopped, and making it possible to stably supply carbon dioxide gas.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an example of a general evaporative seawater desalination device, FIG. 2 is an explanatory diagram of a first embodiment of the device of the present invention, and FIG. 3 is a diagram of a second embodiment of the device of the present invention. FIG. 4 is an explanatory diagram of a third embodiment of the apparatus of the present invention. Flow tube, 8.19 is 1 dioctor, 10 is melting tower, 11 is carbonic acid gas solution supply pipe, 14 is barometric condenser.
15 is a distilled water pipe, 22 is a condenser, 23 is a vacuum pump, and 24 is an absorption tower. Patent application Hitoshi Kawajima Harima Heavy Industries Co., Ltd.

Claims (1)

[Claims] 1) A bleed pipe is connected to each condenser on the high-temperature stage side of the evaporative water desalination equipment, and a bleed device and a dissolution/absorption device are sequentially installed downstream in a confluence pipe that communicates with each bleed pipe. Characteristic carbon dioxide recovery equipment.