WO2013051750A1

WO2013051750A1 - Dissolved carbon dioxide concentration control method for carbon dioxide-fixing device using carbonated water

Info

Publication number: WO2013051750A1
Application number: PCT/KR2011/007958
Authority: WO
Inventors: 박종익; 박정우; 박종락
Original assignee: 주식회사 삼에스코리아
Priority date: 2011-10-04
Filing date: 2011-10-25
Publication date: 2013-04-11
Also published as: KR101250856B1

Abstract

The present invention relates to a dissolved carbon dioxide concentration control method for a carbon dioxide-fixing device using carbonated water, and more specifically, the method enables the carbon dioxide concentration of a culture water to be more effectively controlled, so as to meet the optimum culture conditions for microalgae, by means of indirect carbon dioxide concentration measuring methods measuring the pH of the culture water in a collected-water tank or the amount of oxygen (O₂) discharged from the collected-water tank, and thus also enables a reduction in the initial equipment costs of a carbon dioxide-fixing device by using a pH measuring device or an oxygen (O₂) measuring device instead of an expensive carbon dioxide concentration measuring device.

Description

Method for Controlling Dissolved Carbon Dioxide in Carbon Dioxide Fixture Using Carbonated Water

The present invention relates to a method for controlling the dissolved carbon dioxide concentration of a carbon dioxide fixing device using carbonated water, and more particularly, to control the dissolved carbon dioxide concentration to maintain the optimum culture conditions of microalgae grown for carbon dioxide capture in the collection tank. It relates to a method for controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device using.

As is well known, carbon dioxide is a gas produced by the complete combustion of carbon or its compounds, or by the respiration or fermentation of living organisms, accounting for about 0.03% of the atmosphere.

Carbon dioxide is a kind of greenhouse gas that causes global warming. As the industrialization of modern society accelerates, the amount of carbon dioxide in the atmosphere increases every year as the amount of fossil fuel increases.

Recently, in order to reduce greenhouse gases, studies are being actively conducted to reduce and store approximately carbon dioxide in various countries around the world.

Among them, carbon dioxide fixation technology using vegetation such as plants or microalgae, unlike other physical and chemical recovery methods, uses solar energy as a light source, so the investment and operation cost are low, and the secondary treatment cost due to the generation of environmentally harmful substances This does not take, and has the advantage that can greatly contribute to the landscape creation.

In addition, it has the advantage that it can be used to extract useful substances, such as medicine, dried food, colorants, enzymes from the microalgae obtained after carbon dioxide treatment.

However, in the case of a carbon dioxide fixing device using a conventional microalgae, by supplying the exhaust gas containing carbon dioxide in a bubble state in which the microalgae is cultured in a bubble state, the amount of carbon dioxide dissolved in the tank is limited by the carbon assimilation of the microalgae cultured. The amount of carbon dioxide that can be collected is reduced and a large amount of carbon dioxide which is not dissolved in water is released into the air.

Therefore, in the Republic of Korea Patent Application No. 2011-0071935, previously filed by the same applicant to solve the above problems using a microalgae that is cultured by supplying carbonated water prepared by dissolving carbon dioxide in water using a carbonated water maker into the collection tank Disclosed is a "carbon dioxide reduction device and a carbon dioxide reduction method using the same" for capturing carbon dioxide.

In the case of the carbon dioxide fixing device using the microalgae, carbonated water dissolved in carbon dioxide is used as the culture water, so if the carbon dioxide concentration of the carbonated water is not suitable for algae growth, the microalgae growth is not performed normally, and thus the carbon dioxide collection efficiency is reduced. do.

Therefore, in order to maintain a constant carbon dioxide concentration of the culture water according to the growth of the microalgae in the conventional carbon dioxide fixing device was used a carbon dioxide concentration meter for monitoring the carbon dioxide concentration of the culture water.

However, since most carbon dioxide concentration meters are limited to within 30% of the measurement range, the method of directly measuring carbon dioxide is difficult to apply, and it is expensive to use a high-precision carbon dioxide concentration meter for more accurate measurement. The disadvantage is that the equipment cost of the apparatus is excessively increased.

An object of the present invention for solving the above problems, the concentration of the optimum dissolved carbon dioxide in the culture water for the growth of microalgae more easily and conveniently through the bypass method without directly measuring the dissolved carbon dioxide concentration of the culture water using a carbon dioxide concentration meter. It is to provide a method for controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device using carbonated water to maintain.

In the method for controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device using the carbonated water of the present invention for achieving the above object, the carbon dioxide is dissolved in water using a carbonated water maker to produce carbonated water, and the carbonated water supplied from the carbonated water maker in the collection tank In the method of controlling the carbon dioxide concentration of the carbonated water supplied into the collection tank in the carbon dioxide reduction device for culturing the microalgae using the culture water as a culture water, and collects carbon dioxide by the carbon assimilation of the microalgae, Set the optimum pH value of the culture water for the growth of the microalgae, and measure the pH value of the culture water in the collection tank, the carbonated water according to the change amount of the pH measurement value based on the optimum pH set value Dissolved carbon dioxide by varying the amount of carbon dioxide dissolved Characterized by controlling the concentration.

Here, as the measured pH value is lowered based on the optimum pH set value, it is preferable to control to increase the amount of carbon dioxide dissolved in the carbonated water.

In another method of controlling carbon dioxide concentration of a carbon dioxide fixing device using carbonated water of the present invention, carbon dioxide is dissolved in water using a carbonated water maker to produce carbonated water, and microalgae using carbonated water supplied from the carbonated water maker in a collection tank is cultured. In the method of controlling the carbon dioxide concentration of the carbonated water supplied into the collection tank in the carbon dioxide reduction device for capturing carbon dioxide by the carbon assimilation of the microalgae, for the growth of the microalgae in the collection tank Set the optimum dissolved carbon dioxide concentration of the culture water, measure the amount of oxygen (O2) discharged from the collection tank, and control the carbon dioxide concentration by varying the amount of carbon dioxide dissolved in the carbonated water according to the measured oxygen discharge Characterized by do.

Here, the carbon dioxide supply amount is preferably made of the weight ratio of 44: 32 and the oxygen emissions.

According to the method for controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device using the carbonated water of the present invention, by measuring the pH value of the culture water in the collection tank or by-pass to measure the oxygen (O ₂ ) discharged from the collection tank Phosphorus-dissolved carbon dioxide (CO ₂ ) concentration measurement methods have the effect of more effectively controlling the carbon dioxide concentration value in the culture water to have an optimum culture conditions of microalgae.

In addition, according to the method for controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device using the carbonated water of the present invention, by using a pH meter or an oxygen meter in place of the expensive carbon dioxide concentration meter has the effect of reducing the equipment cost of the carbon dioxide fixing device. .

1 is a schematic diagram showing a carbon dioxide fixing device according to a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating a process for controlling dissolved carbon dioxide concentration of carbonated water in the carbon dioxide fixing device of FIG. 1.

3 is a schematic view showing a carbon dioxide fixing device according to a second embodiment of the present invention.

4 is a flowchart illustrating a process for controlling dissolved carbon dioxide concentration of carbonated water in the carbon dioxide fixing device of FIG. 3.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and like reference numerals designate like elements throughout the specification.

Referring to FIG. 1, the carbon dioxide fixing device 1 of the present embodiment includes a carbonated water producer 20, a collection tank 10, a pH meter 35, and a controller 30.

The carbonated water maker 20 is configured to dissolve carbon dioxide in a gaseous state contained in air or exhaust gas in water to produce carbonated water as shown in Chemical Formula 1 below.

Formula 1

On the other hand, the carbonated water maker 20 is preferably configured to enable the control of the carbon dioxide concentration in the carbonated water supplied into the collection tank 10 according to the control signal of the controller 30 to be described later.

In the present embodiment, the carbonated water producer 20 used in the carbon dioxide fixing device 1 exemplifies that the carbonated water producer 20 is formed of an explosive carbonated water maker which aerations and dissolves gaseous carbon dioxide in a pressure vessel containing water.

However, the present invention is not necessarily limited thereto, and it is obvious that the present invention may be modified and applied in various forms as long as carbon dioxide is dissolved in water to prepare carbonated water to control carbon dioxide concentration.

The collection tank 10 is configured to incubate the microalgae 11 using the carbonated water supplied from the carbonated water maker 20 as the cultured water 12 to capture carbon dioxide dissolved in the carbonated water by their carbon assimilation. .

Here, the process of capturing carbon dioxide through carbon assimilation using the photosynthesis of the microalgae 11 of the carbonated water supplied to the collection tank 10 is performed through the processes of Formulas 2 and 3 below.

Formula 2

Formula 3

Here, H ₂ A may include both microalgae using hydrogen, fatty acids, and alcohols in addition to water and hydrogen sulfide.

Therefore, the carbon dioxide abatement apparatus 1 using the microalgae of the present embodiment may dissolve carbon dioxide in water to produce carbonated water and increase the fixed efficiency of carbon dioxide by carbon assimilation of microalgae cultured in the produced carbonated water. do.

On the other hand, the pH meter 35 is fixed to the collection tank 10 to measure the pH value of the culture water 12 in the collection tank (10).

Then, the controller 30 is supplied into the collection tank 10 manufactured from the carbonated water maker 20 according to the pH value of the collection water tank 10 of the culture water 12 measured by the pH meter 35. It is to adjust the dissolved carbon dioxide concentration of the carbonated water 12.

FIG. 2 is a flowchart illustrating a carbon dioxide concentration control process of the carbon dioxide fixing device of FIG. 1.

As shown in Figure 2, the carbon dioxide concentration control method of the carbon dioxide fixing device of the present embodiment is the collection tank through the optimal pH value setting (ST11), culture water pH value measurement (ST12) and carbon dioxide concentration control of the carbonated water (ST13) step It is possible to maintain the optimum carbon dioxide concentration value in the culture water 12 for culturing the microalgae (11) in (10).

First, in the step of setting the optimum pH value (ST11), by using the pH meter 35 installed in the collection tank 10, by measuring the pH value when the carbon dioxide concentration value that satisfies the optimum culture conditions of the microalgae 11, Set to pH setpoint.

At this time, the optimum pH value is set such as the capacity of the culture water 12 accommodated in the collection tank, the temperature of the culture water 12, the intensity of light energy irradiated into the culture water 12 and the growth rate according to the type of microalgae Considering the conditions, the optimum range for each variable is set.

In the cultured water pH value measurement (ST12) step, the pH value of the cultured water 12 is continuously monitored and monitored using a pH meter 35 installed in the collection tank 10 continuously during the operation of the carbon dioxide fixing device. Do it.

On the other hand, the optimal pH set value is stored in the controller 30 in a database state according to each setting condition, the continuously measured pH measurement value is input to the controller 30 to maintain the optimum carbon dioxide concentration Stored and compared with the optimum pH setpoint described above.

In the step of controlling carbon dioxide concentration of carbonated water (ST13), the controller 30 calculates a change amount of the pH measurement value based on the optimum pH set value, and through the carbonated water maker 20 according to the change amount of the pH measurement value. Variable control of the carbon dioxide concentration value in the carbonated water supplied into the collection tank.

Here, as the pH value of the culture water decreases, it means that the amount of carbon dioxide dissolved in the culture water decreases.

Therefore, as the pH measured value is lowered based on the optimal pH set value, the carbon dioxide concentration of the carbonated water supplied to the collection tank 10 is increased by increasing the input amount of carbon dioxide, that is, the detonation amount, and setting the optimum pH. As the pH measurement value is lowered based on the value, the amount of carbon dioxide is reduced to control the carbon dioxide concentration value of the carbonated water supplied to the collection tank 10 so that the culture water in the collection tank is optimally dissolved in microalgae culture. It is possible to maintain the carbon dioxide concentration.

As such, through the method of controlling the carbon dioxide concentration of the carbon dioxide fixing device using the carbonated water of the present embodiment, the right turn to measure the pH value of the culture water in the collection tank 10 using the pH meter 35 is easier, simpler and lower cost. This has the effect of controlling the dissolved carbon dioxide concentration in the culture water for the optimum culture conditions of the microalgae (11).

Hereinafter, a method of controlling carbon dioxide concentration of a carbon dioxide fixing device using carbonated water according to a second embodiment of the present invention will be described with reference to the accompanying drawings, and the same reference numerals are used for the same and similar components as those of the first embodiment. The repeated description thereof will be omitted.

3 is a schematic diagram illustrating a carbon dioxide fixing device according to a second embodiment of the present invention, and FIG. 4 is a flowchart illustrating a process for controlling dissolved carbon dioxide concentration of carbonated water in the carbon dioxide fixing device of FIG. 3.

Referring to FIG. 3 and FIG. 4, the carbon dioxide fixing device 100 of the present embodiment replaces the pH meter 35 installed in the collection tank 10 as compared to the carbon dioxide fixing device 1 of the first embodiment. The difference between the configuration of the oxygen measuring pipe 40 for measuring the amount of oxygen (O ₂ ) discharged through the oxygen exhaust pipe 45 and the oxygen exhaust pipe 45 is installed to cover the upper side of the collection tank (10) Has

Therefore, the method for controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device of the present embodiment is performed by setting the optimal dissolved carbon dioxide concentration (ST101), measuring the oxygen emission amount (ST102), and controlling the dissolved carbon dioxide concentration of the carbonated water (ST103).

In the step of setting the optimal dissolved carbon dioxide concentration (ST101), the range of the optimal dissolved carbon dioxide concentration for the growth of the microalgae in the collection tank 10 is set according to the above-described conditions using the carbon dioxide concentration measuring device 36. do.

At this time, the carbon dioxide concentration measuring device 36 is for setting the range of the carbon dioxide concentration value of the optimum range of the culture water is not necessarily fixed to be installed in the collection tank 10, the initial stage of the carbon dioxide fixing device 100 The cost of equipment can be reduced.

In the step of measuring oxygen emission (ST102), the oxygen measuring unit 40 measures the amount of oxygen (O ₂ ) produced by the carbonization of the microalgae in the collection tank 10 and discharged through the oxygen discharge pipe 45. do.

In the step of controlling dissolved carbon dioxide concentration of carbonated water (ST103), the amount of carbon dioxide dissolved in the carbonated water is varied through the controller 30 to control the carbon dioxide concentration.

That is, after the initial conditions are set so that the dissolved carbon dioxide concentration of the culture water in the collection tank 10 is optimal for microalgal growth, the amount of oxygen discharged from the collection tank 10 is measured, and the same according to the measured oxygen discharge amount. By varying the carbon dioxide input at a ratio, the optimum carbon dioxide concentration value is continuously maintained.

At this time, the carbon dioxide supply amount is preferably made to the oxygen emissions and 44: 32% by weight ratio.

The entire process of photosynthesis by the microalgae 11 in the collection tank 10 is oxygen (O ₂ ) is generated through the photosynthetic light reaction, as shown in the following formula (4), glucose through the cancer reaction (C ₃ H ₁₂ O ₆ ) Is synthesized and generates water (H ₂ O).

Formula 4

That is, 6 mol (mol) of carbon dioxide (CO ₂ ) is consumed to produce 1 mol (mol) of glucose (C ₃ H ₁₂ O ₆ ) and 6 mol (mol) of oxygen (O ₂ ).

Therefore, in order to generate 1 mol (32 g) of oxygen (O ₂ ), since 1 mol (mol; 44 g) of carbon dioxide (CO ₂ ) is required at the same ratio, the carbon dioxide supply amount is 44: 32 By weight percent to maintain a constant dissolved carbon dioxide concentration value in the culture.

As such, in the method of controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device using the carbonated water of the present embodiment, the optimal cultivation of microalgae at a simpler and lower cost through the right rotation method of measuring the oxygen (O 2) emission discharged from the collection tank 10. It has the effect of controlling the dissolved carbon dioxide concentration value in the culture water for the conditions.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications or changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. In addition, it is natural that it belongs to the scope of the present invention.

1, 100: carbon dioxide fixing device 10: collection tank

11: microalgae 12: cultured water (carbonated water)

20: carbonated water maker 30: controller

35: pH meter 36: carbon dioxide concentration meter

40: oxygen measuring instrument 45: oxygen discharge pipe

Claims

Carbonated water is prepared by dissolving carbon dioxide in water using a carbonated water maker,

Incubating the microalgae in the collection tank using the carbonated water supplied from the carbonated water maker as culture water,

In the method of controlling the dissolved carbon dioxide concentration of the carbonated water supplied into the collection tank in the carbon dioxide reduction device for collecting carbon dioxide by the carbon assimilation of the microalgae,

Setting an optimum pH value of the culture water for the growth of the microalgae in the collection tank;

By measuring the pH value of the culture water in the collection tank,

The method of controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device using carbonated water to control the dissolved carbon dioxide concentration by varying the amount of carbon dioxide dissolved in the carbonated water according to the change amount of the pH measurement value based on the optimum pH set value.
In claim 1,

The method of controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device using carbonated water to control to increase the amount of carbon dioxide dissolved in the carbonated water, the lower the measured pH value based on the optimum pH set value.
Carbonated water is prepared by dissolving carbon dioxide in water using a carbonated water maker,

Incubating the microalgae in the collection tank using the carbonated water supplied from the carbonated water maker as culture water,

In the method of controlling the dissolved carbon dioxide concentration of the carbonated water supplied into the collection tank in the carbon dioxide reduction device for collecting carbon dioxide by the carbon assimilation of the microalgae,

Setting an optimal dissolved carbon dioxide concentration of the culture water for the growth of the microalgae in the collection tank,

By measuring the oxygen (O2) emissions discharged from the collection tank,

The method of controlling the dissolved carbon dioxide concentration of the carbon dioxide fixing device using the carbonated water to control the dissolved carbon dioxide concentration by varying the amount of carbon dioxide dissolved in the carbonated water according to the measured oxygen emissions.
In claim 3,

The carbon dioxide supply amount is the dissolved carbon dioxide concentration control method of the carbon dioxide fixing device using carbonated water in the ratio of 44: 32% by weight of the oxygen discharge.