Method for synchronously increasing marine alkalinity and diatom quantity

Abstract

The invention relates to the technical field of marine acidification modification, and discloses a method for synchronously increasing marine alkalinity and diatom quantity. The method comprises the following steps: mixing a dispersion carrier and brucite according to a mass ratio of (0.02-0.4): 1, and adding the mixture into seawater; wherein the dispersion carrier comprises at least one of diatom opal and clay mineral. The dispersing carrier and the brucite are mixed according to a specific proportion, the brucite can be dispersed, loaded and adsorbed to a certain degree, the reaction speed of the brucite and carbon dioxide in a water body is inhibited, the intensity is reduced, meanwhile, the dispersing carrier also has a heat absorption effect, the pH increasing speed can be reduced to 1 / 6-1 / 40 through the heat absorption effect, and the pH value of the water body is increased. The stability of a water body environment is effectively ensured, so that the activity inhibition on organisms such as diatom is reduced, even the activity is improved, and the effect of synchronously improving the marine alkalinity and the number of diatom is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of ocean acidification modification, and in particular to a method for synchronously increasing ocean alkalinity and the number of diatoms. Background Art

[0002] Ocean acidification refers to the phenomenon that the ocean absorbs excessive carbon dioxide, causing the pH of seawater to decrease. Ocean acidification will change the chemical balance of seawater, posing a huge threat to marine life and even the entire marine ecosystem. Take diatoms, an important carbon-fixing organism in the world, as an example. Diatoms are one of the most efficient photosynthetic organisms, contributing about 20% of the world's primary productivity and about 20% of carbon fixation, and have a significant impact on the level of atmospheric carbon dioxide concentration. When the ocean acidifies, the size of diatom cells becomes smaller, and the growth and photosynthetic rates decrease significantly.

[0003] Brucite is an alkaline mineral and the mineral with the highest magnesium content in nature. Its main component is hydrated magnesium hydroxide, so it is easy to react with carbon dioxide and can effectively reduce water acidification. However, when using brucite for ocean acidification control, although direct use, such as scattering into seawater, can increase the pH of the ocean in a short period of time, there are also some problems that make it difficult to promote in ocean acidification control.

[0004] The main problem is that after brucite is added, it will quickly react with carbon dioxide in the water, thus having a bad impact on aquatic microorganisms. This is mainly reflected in two aspects: brucite reacts violently with carbon dioxide in water, releasing a certain amount of heat, causing the local seawater temperature to rise, resulting in a decrease in the activity of photosynthetic organisms such as diatoms. In addition, after brucite reacts with carbon dioxide in the water, the pH of the water body rises rapidly, causing the local environmental pH to be too high, which also affects the activity of aquatic organisms such as diatoms.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The object of the present invention is to provide a method for synchronously increasing the alkalinity of the ocean and the number of diatoms.

[0007] The present invention is achieved in that:

[0008] In a first aspect, the present invention provides a method for simultaneously increasing the alkalinity of the ocean and the number of diatoms, comprising mixing a dispersion carrier with brucite in a mass ratio of 0.02-0.4:1, and then adding the mixture to seawater; wherein the dispersion carrier comprises at least one of diatom opal and clay minerals.

[0009] In an optional embodiment, the mass ratio of the dispersed carrier to the brucite is 0.1-0.4:1.

[0010] In an optional embodiment, the dispersed carrier and the brucite are mixed by ball milling for 30-60 min, and the ball milling speed is 400-800 rpm;

[0011] Preferably, the mixture has a particle size of 5-23 μm.

[0012] In an optional embodiment, before the dispersion carrier is mixed with the brucite, the dispersion carrier is further crushed to a particle size of ≤100 μm.

[0013] In an optional embodiment, the mass volume ratio of the brucite to the seawater is (40-60) g:1L.

[0014] In an optional embodiment, the clay mineral is a clay mineral with a 2:1 type crystal structure.

[0015] In an alternative embodiment, the clay mineral includes at least one of montmorillonite and illite.

[0016] In an optional embodiment, after the mixture is added to the seawater, the pH growth rate is reduced to 1 / 6-1 / 40 of that without the mixture.

[0017] In an optional embodiment, after the mixture is added to the seawater, the amount of soluble inorganic carbon increases by 59.5%-127.4%.

[0018] In an optional embodiment, after the mixture is added to the seawater, the increase in the number of diatoms is increased by 2%-19%.

[0019] The present invention has the following beneficial effects:

[0020] The method for synchronously improving the alkalinity of the ocean and the number of diatoms provided by the present invention utilizes a dispersion carrier (at least one of diatom opal and clay mineral) and brucite to mix in a specific ratio, so that brucite can be dispersed, loaded and adsorbed to a certain extent, thereby inhibiting the reaction rate of brucite with carbon dioxide in the water body and reducing the severity. At the same time, the dispersion carrier also has an endothermic effect. Combining this effect, the pH increase rate after the reaction of brucite with carbon dioxide can be reduced to 1 / 6-1 / 40 of that before the mixture is added, effectively ensuring the stability of the water environment, thereby reducing the activity inhibition of organisms such as diatoms, and even improving their activity. After the mixture is added to the seawater, the amount of soluble inorganic carbon is increased by 59.5%-127.4%, and the increase in the number of diatoms is increased by 2%-19%, which has the effect of synchronously improving the alkalinity of the ocean and the number of diatoms. The method for synchronously improving the alkalinity of the ocean and the number of diatoms provided by the present invention is efficient, easy to implement, low-cost, and easy to promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 This is a scanning electron microscope image of the complex of diatom opal and brucite provided in Example 1 of the present invention, wherein the cylindrical shape is a single diatom opal particle, and the pore-filling and surface-attached lamellar small particles are brucite. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0024] The present invention provides a method for synchronously increasing the alkalinity of the ocean and the number of diatoms, which comprises mixing a dispersion carrier with brucite in a mass ratio of 0.02-0.4:1, and then adding the mixture into seawater; wherein the dispersion carrier comprises at least one of diatom opal and clay mineral.

[0025] Diatom opal is the main mineral component of diatomite. The specific source of diatom opal is not limited in the present invention. Diatom opal purchased from the market or independently prepared by conventional methods can be used as the raw material of the present invention.

[0026] Clay minerals refer to hydrated aluminum silicate minerals with a layered structure. Clay minerals are divided into clay minerals with a 1:1 crystal structure and clay minerals with a 2:1 crystal structure. In the present invention, clay minerals with a 2:1 crystal structure are selected as raw materials, which have better dispersion and loading effects. Clay minerals with a 2:1 crystal structure may include, for example, montmorillonite and illite.

[0027] In the present invention, by mixing the dispersion carrier with brucite, the dispersion carrier has a porous structure, which can achieve the dispersion and loading of brucite, thereby inhibiting the reaction rate of brucite with carbon dioxide in the water body and reducing the intensity. At the same time, the diatom opal and clay minerals in the dispersion carrier also have an endothermic effect. Combined with this effect, the heat release and pH increase rate after the reaction of brucite with carbon dioxide can be reduced, thereby reducing the inhibition of the activity of organisms such as diatoms, and even improving their activity.

[0028] Specifically, the dispersion carrier is firstly crushed to a particle size of ≤100 μm, and then the dispersion carrier and brucite are ball-milled for 30-60 min and the ball-milling speed is 400-800 rpm. By mixing under the above conditions, the particle sizes of the dispersion carrier and brucite can be reduced during the ball milling process, and the brucite is loaded into the dispersion carrier by mechanical force. The finally obtained mixture is passed through a 600-800 mesh sieve, and a sample with a particle size of 5-23 μm is screened out as the mixture of the present invention.

[0029] In the present invention, the mass ratio of the dispersion carrier to brucite is 0.02-0.4:1, preferably, the mass ratio of the dispersion carrier to brucite is 0.1-0.4:1. It can be seen that in the present application, a small amount of dispersion carrier can be used to achieve the dispersion and loading of brucite.

[0030] When the mixture is added to seawater, the mass volume ratio of brucite to seawater is (40-60) g:1L. After the mixture is added to seawater, the amount of soluble inorganic carbon increases by 59.5%-127.4%, the pH growth rate is reduced to 1 / 6-1 / 40 of that without the addition of the mixture, and the increase in the number of diatoms increases by 2%-19%.

[0031] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0032] It should be noted that the examples and comparative examples provided in the present application were all prepared in a laboratory, wherein seawater was placed in a container and sealed with a sealing device to ensure the accuracy of the detection of carbon dioxide therein.

[0033] Example 1

[0034] This embodiment provides a method for simultaneously increasing the alkalinity of the ocean and the number of diatoms, which comprises: initially crushing diatom opal to a particle size of ≤100 μm, then ball-milling 1 g of diatom opal and 50 g of brucite, the mixing time is 40 min, and the ball-milling speed is 400 rpm; the obtained mixture has a particle size of 23 μm, see Figure 1 It can be seen that brucite is loaded in the pores and on the surface of diatom opal. The mixture was added to 1 liter of seawater with a pH of 8.0. After the reaction was complete, the amount of soluble inorganic carbon in the seawater, the increase rate of seawater pH value and the number of diatoms were detected.

[0035] Example 2

[0036] The present embodiment provides a method for synchronously increasing the alkalinity of the ocean and the number of diatoms, which comprises: preliminarily crushing diatom opal to a particle size of ≤100 μm, then ball-milling 5 g of diatom opal and 50 g of brucite, the mixing time is 40 min, and the ball milling speed is 600 rpm; the obtained mixture has a particle size of 20 μm, and the mixture is added to 1 liter of seawater with a pH of 8.0. After the reaction is complete, the amount of soluble inorganic carbon in the seawater, the increase rate of the pH value of the seawater, and the number of diatoms are detected.

[0037] Example 3

[0038] The present embodiment provides a method for synchronously increasing the alkalinity of the ocean and the number of diatoms, which comprises: preliminarily crushing diatom opal to a particle size of ≤100 μm, then ball-milling 10 g of diatom opal and 50 g of brucite, the mixing time is 40 min, and the ball milling speed is 800 rpm; the obtained mixture has a particle size of 8 μm, and the mixture is added to 1 liter of seawater with a pH of 8.0. After the reaction is complete, the amount of soluble inorganic carbon in the seawater, the increase rate of the pH value of the seawater, and the number of diatoms are detected.

[0039] Example 4

[0040] The present embodiment provides a method for synchronously increasing the alkalinity of the ocean and the number of diatoms, which comprises: preliminarily crushing montmorillonite to a particle size of ≤100 μm, then ball-milling 10 g of montmorillonite and 50 g of brucite, the mixing time is 40 min, and the ball milling speed is 400 rpm; the obtained mixture has a particle size of 20 μm, and the mixture is added to 1 liter of seawater with a pH of 8.0. After the reaction is complete, the amount of soluble inorganic carbon in the seawater, the increase rate of the pH value of the seawater, and the number of diatoms are detected.

[0041] Example 5

[0042] The present embodiment provides a method for synchronously increasing the alkalinity of the ocean and the number of diatoms, which comprises: preliminarily crushing montmorillonite to a particle size of ≤100 μm, then ball-milling 10 g of montmorillonite and 50 g of brucite, the mixing time is 40 min, and the ball milling speed is 800 rpm; the obtained mixture has a particle size of 19 μm, and the mixture is added to 1 liter of seawater with a pH of 8.0. After the reaction is complete, the amount of soluble inorganic carbon in the seawater, the increase rate of the pH value of the seawater, and the number of diatoms are detected.

[0043] Example 6

[0044] The present embodiment provides a method for synchronously increasing the alkalinity of the ocean and the number of diatoms, which comprises: preliminarily crushing montmorillonite to a particle size of ≤100 μm, then ball-milling 10 g of montmorillonite, 50 g of brucite and 10 g of diatom opal, the mixing time is 60 min, and the ball milling speed is 800 rpm; the obtained mixture has a particle size of 5 μm, and the mixture is added to 1 liter of seawater with a pH of 8.0. After the reaction is complete, the amount of soluble inorganic carbon in the seawater, the increase rate of the pH value of the seawater and the number of diatoms are detected.

[0045] Example 7

[0046] This embodiment is substantially the same as Embodiment 1, except that the amount of diatom opal used in this embodiment is replaced from 1 g to 20 g.

[0047] Example 8

[0048] This embodiment is substantially the same as embodiment 3, except that the amount of brucite used in this embodiment is replaced by 40 g from 50 g.

[0049] Example 9

[0050] This embodiment is substantially the same as embodiment 3, except that the amount of brucite used in this embodiment is replaced by 60 g from 50 g.

[0051] Comparative Example 1

[0052] The present comparative example provides a method for improving the alkalinity of the ocean, which comprises: ball-milling brucite for 40 minutes at a ball-milling speed of 800 rpm; obtaining particles with a particle size of 12 μm, directly adding 50 g of brucite into 1 liter of seawater with a pH of 8.0, and after the reaction is complete, detecting the amount of soluble inorganic carbon in the seawater, the increase rate of the pH value of the seawater, and the number of diatoms.

[0053] Comparative Example 2

[0054] This comparative example provides a method for increasing the alkalinity of the ocean, which comprises: preliminarily crushing diatom opal to a particle size of ≤100 μm, then ball-milling 10 g of the diatom opal for 40 min at a ball-milling speed of 800 rpm; until the particle size is 10 μm, adding 10 g of the diatom opal to 1 liter of seawater at a pH of 8.0, and after the reaction is complete, detecting the amount of soluble inorganic carbon in the seawater, the increase rate of the pH value of the seawater, and the number of diatoms.

[0055] Comparative Example 3

[0056] This comparative example provides a method for increasing the alkalinity of the ocean, which comprises: mixing 50 g of brucite with 100 mL of 0.01 mol / L phosphate buffer (1:1 NaH2PO4 and Na2HPO4), then adding the mixture to 1 liter of seawater with a pH of 8.0, and after the reaction is complete, detecting the amount of soluble inorganic carbon in the seawater, the increase rate of the pH value of the seawater, and the number of diatoms.

[0057] Comparative Example 4

[0058] This comparative example provides a method for increasing the alkalinity of the ocean, which comprises: mixing 50 g of brucite with 100 mL of 0.2 mol / L glycine buffer, then adding the mixture to 1 liter of seawater with a pH of 8.0, and after the reaction is complete, detecting the amount of soluble inorganic carbon in the seawater, the increase rate of the pH value of the seawater, and the number of diatoms.

[0059] Comparative Example 5

[0060] This comparative example provides a method for increasing the alkalinity of the ocean, comprising: mixing 50 g of brucite with 100 mL of Cis buffer solution with a pH of 8.0, wherein the Cis buffer solution is prepared by using 1 L of 12.14 g of tris(hydroxymethyl)aminomethane) buffer solution and adjusting with 6 M hydrochloric acid, and then adding the mixture to 1 liter of seawater with a pH of 8.0, and after the reaction is complete, detecting the amount of soluble inorganic carbon in the seawater, the growth rate of the seawater pH value, and the number of diatoms.

[0061] Comparative Example 6

[0062] This comparative example is basically the same as Example 1, except that in this comparative example, the diatom opal and brucite are not ball-milled, but directly mechanically stirred and mixed. At this time, the particle size of the mixture is 5-10 cm.

[0063] Experimental example

[0064] The seawater after the reaction of the above-mentioned Examples 1-9 and Comparative Examples 1-6 was tested, wherein the method for testing the dissolved inorganic carbon content in the seawater includes a non-dispersive infrared absorption method, and the specific operation steps are: adding an excess of 10% phosphoric acid to a certain volume of seawater sample so that the HCO3 in the seawater - and CO3 2- All of them are converted into CO2. After nitrogen purge, the generated CO2 is first dried in a drying tube, then detected by a Li-7000 non-dispersive infrared detector, and quantified by peak area. The pH value of seawater is detected by using a pH meter; the number of diatoms is detected by using a diatom counter (CountStar IA1000, Shanghai Ruiyu Biotechnology Co., Ltd.).

[0065] Please refer to Table 1 for the test results.

[0066] Table 1. Statistics of detection results for different examples

[0067]

[0068] At the same time, the reaction process of the above-mentioned Examples 1-9 and Comparative Examples 1-6 is observed. At the same time, combined with the above table, it can be seen that in Example 1, due to the small amount of diatom opal added, the pH rises faster, and at the same time, the amount of dissolved inorganic carbon and diatoms is low. In Example 2-3, the amount of diatom opal is increased, and it can be seen that the pH rise rate is gradually reduced, and at the same time, the amount of dissolved inorganic carbon and diatoms is also significantly increased. In Example 4-6, montmorillonite is selected as a dispersion carrier to prepare a mixture of different particle sizes, which still has a good effect, and the smaller the particle size of the mixture, the lower the pH rise rate, and at the same time, the amount of dissolved inorganic carbon and diatoms is also significantly increased. In Example 7, the amount of diatom protein in Example 1 is increased, which will significantly reduce the amount of pH rise, and at the same time, significantly increase the amount of dissolved inorganic carbon and diatoms. As can be seen from Example 8-9, the increase or decrease in the amount of brucite has a certain effect on the amount of pH rise, the amount of dissolved inorganic carbon and diatoms, but the amount adjustment within the scope of this application can achieve better results. In comparative example 1, only brucite is added, and the reaction occurs rapidly at this time, and the amount of dissolved inorganic carbon is significantly higher than that in Example 1. At the same time, accompanied by the rapid increase of pH, the growth of diatoms is significantly inhibited, and the phenomenon of partial diatom death occurs, and the number of diatoms is reduced by 35%. In comparative example 2, only diatom opal is added, and the solubility of carbon dioxide does not increase at this time. In comparative example 3, phosphate buffer is selected, and at this time, phosphate buffer is easily associated with calcium, magnesium ions and metal ions to form precipitation, which will inhibit certain biochemical processes and inhibit the activity of most enzymes. In comparative example 4, amino acid buffer is selected, and amino acid buffer will interfere with certain biochemical reaction processes; in comparative example 5, Cis buffer is selected, and there is also interference, which leads to less reduction in carbon dioxide content, faster increase in pH and less increase in the number of diatoms, and comparative example 5 uses an organic buffer, which has a greater harm to the environment. In Comparative Example 6, the diatom opal and brucite were not ball-milled, but only mechanically stirred and mixed. At this time, the particle size of the mixture was relatively large, and the brucite was not completely loaded in the porous structure of the diatom opal, which would cause the pH to rise faster, but it was difficult to completely dissolve and play the role of absorbing carbon dioxide.

[0069] In summary, the method for synchronously improving the alkalinity of the ocean and the number of diatoms provided by the present invention utilizes a dispersion carrier (at least one of diatom opal and clay mineral) and brucite to mix in a specific ratio, so that brucite can be dispersed, loaded and adsorbed to a certain extent, thereby inhibiting the reaction rate of brucite with carbon dioxide in the water body and reducing the severity. At the same time, the dispersion carrier also has an endothermic effect. Combining this effect, the pH increase rate after the reaction of brucite with carbon dioxide can be reduced to 1 / 6-1 / 40 of that without adding the mixture, effectively ensuring the stability of the water environment, thereby reducing the inhibition of the activity of organisms such as diatoms, and even improving their activity. After the mixture is added to the seawater, the increase in the amount of soluble inorganic carbon is 59.5%-127.4%, and the increase in the number of diatoms is increased by 2%-19%, which has the effect of synchronously improving the alkalinity of the ocean and the number of diatoms. The method for synchronously improving the alkalinity of the ocean and the number of diatoms provided by the present invention is efficient, easy to implement, low-cost, and easy to promote.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for simultaneously increasing the alkalinity of the ocean and the number of diatoms, characterized in that: The method comprises mixing a dispersion carrier and brucite in a mass ratio of 0.02-0.4:1, and then adding the mixture into seawater; wherein the dispersion carrier comprises at least one of diatom opal and clay mineral.

2. The method for synchronously increasing ocean alkalinity and diatom quantity according to claim 1, characterized in that: The mass ratio of the dispersed carrier to the brucite is 0.1-0.4:

1.

3. The method for synchronously increasing ocean alkalinity and diatom quantity according to claim 1, characterized in that: The dispersed carrier and the brucite are mixed by ball milling for 30-60 minutes at a ball milling speed of 400-800 rpm; Preferably, the mixture has a particle size of 5-23 μm.

4. The method for synchronously increasing ocean alkalinity and diatom quantity according to claim 1, characterized in that: Before the dispersion carrier is mixed with the brucite, the dispersion carrier is crushed to a particle size of ≤100 μm.

5. The method for synchronously increasing ocean alkalinity and diatom quantity according to claim 1, characterized in that: The mass volume ratio of the brucite to the seawater is (40-60) g:1L.

6. The method for synchronously increasing ocean alkalinity and diatom quantity according to claim 1, characterized in that: The clay mineral is a clay mineral with a 2:1 type crystal structure.

7. The method for synchronously increasing ocean alkalinity and diatom quantity according to claim 6, characterized in that: The clay mineral includes at least one of montmorillonite and illite.

8. The method for synchronously increasing ocean alkalinity and diatom quantity according to claim 1, characterized in that: After the mixture is added to the seawater, the pH growth rate is reduced to 1 / 6-1 / 40 of that without the mixture.

9. The method for synchronously increasing ocean alkalinity and diatom quantity according to claim 1, characterized in that: After the mixture is added to the seawater, the amount of soluble inorganic carbon increases by 59.5%-127.4%.

10. The method for synchronously increasing ocean alkalinity and diatom quantity according to claim 1, characterized in that: After the mixture is added to the seawater, the increase in the number of diatoms is increased by 2%-19%.

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