Method for neutralizing brominated brine through biochemical combination

Abstract

The invention provides a biochemical combination method for neutralizing bromine-containing brine, which comprises the following steps: adding alkaline chemical substances into bromine-extracted brine, and adjusting the pH value to 5 or more; culturing algae and / or microorganisms by using a nutrient solution with the same salinity as the brominated brine; inoculating the algae or microorganisms cultured in the step S2 into the brine with the pH adjusted in the step S1, and adding nutrient elements required by the growth of the cultured algae or microorganisms; and culturing until the pH value of the brine reaches 7 or above. According to the biochemical combination method for neutralizing bromine brine, the pH of bromine extraction waste liquid reaches 5 or above by adding alkaline substances in a chemical and biological combination mode, then algae and microorganisms are inoculated and cultured, the pH of the brine is 7 or above by means of metabolite of the microorganisms and photosynthesis of the algae, the use amount of the alkaline substances is effectively reduced, and the utilization rate of the alkaline substances is increased. Meanwhile, the brine ecology is recovered, and subsequent comprehensive utilization of the brine is facilitated.

Description

Technical Field

[0001] The present invention belongs to the technical field of post-treatment of bromine-extracted brine, and particularly relates to a method for biochemical combined neutralization of bromine-containing brine. Background Art

[0002] Bromine is an important basic chemical raw material and a major pillar of the marine chemical industry. Bromine resources mainly exist in seawater, concentrated brine, sedimentary rock salt ore of ancient oceans, and salt lake water. At present, most domestic enterprises in China adopt the acid method for air-blowing bromine. The first process of bromine extraction from brine is acidification. After bromine extraction, the brine changes from slightly alkaline to strongly acidic, and the chemical composition of the brine has changed greatly. Both chloride ions and sulfate ions increase, and it contains trace amounts of free bromine and ionic bromine. Due to the significant change in the chemical properties of the bromine-extracted brine, the brine ecosystem is relatively thoroughly damaged. Therefore, it is necessary to perform post-treatment on the bromine-extracted brine. At present, domestic enterprises use the method of acid-base neutralization for the treatment of waste liquid after bromine extraction, and add alkaline substances (such as sodium hydroxide, calcium hydroxide, calcium oxide, magnesium oxide, limestone, etc.) for neutralization to adjust the pH to neutral. This leads to the consumption of a large amount of alkaline substances, resulting in an increase in cost. At the same time, the bromine-containing brine treated with alkaline substances also lacks in the comprehensive reuse of brine. Summary of the Invention

[0003] In view of this, to solve the above technical problems, the present invention provides a method for biochemical combined neutralization of bromine-containing brine. By combining chemistry and biology, first, an alkaline substance is added to make the pH of the bromine-extracted waste liquid reach above 5, and then algae and microorganisms are inoculated and cultured. Utilizing the principle that the metabolic products of microorganisms and the photosynthesis of algae consume carbon dioxide and affect the carbon dioxide-carbonate system, the pH of the brine can ultimately be increased to above 7. At the same time, the cultivation of algae and microorganisms is realized. The brine after biological treatment restores the brine ecosystem and can be used for the cultivation of artemia and artemia eggs, achieving the comprehensive reuse of bromine-containing brine.

[0004] To achieve the above object, the technical solution of the present invention is realized as follows:

[0005] A method for biochemical combined neutralization of bromine-containing brine, characterized by comprising the following steps:

[0006] S1. Add an alkaline chemical substance to the bromine-extracted brine and adjust the pH to 5 or above;

[0007] S2. Cultivate algae and / or microorganisms with a nutrient solution having the same salinity as the bromine-containing brine;

[0008] S3. Inoculate the algae or microorganisms cultured in S2 into the brine with the pH adjusted in S1, and add the nutrient elements required for the growth of the cultured algae or microorganisms;

[0009] S4. Cultivate until the pH of the brine reaches 7 or above.

[0010] Furthermore, in the step S1, the alkaline chemical substance is one or more of sodium hydroxide, calcium hydroxide, calcium oxide, magnesium oxide, and limestone.

[0011] Furthermore, in the step S2, the algae are Dunaliella salina, Dunaliella viridis, and / or acclimated Chlorella sp; the microorganisms are Rhodotorula spp and / or Halophilic archaea.

[0012] Furthermore, in the step S3, the inoculation density of the algae is greater than 0.01×10⁴ / ml; the inoculation density of the microorganisms is greater than 2×10 5 cfu / ml.

[0013] Furthermore, in the step S3, the nutrient elements are carbon, nitrogen, phosphorus, and potassium.

[0014] Furthermore, in the step S4, after the pH of the brine reaches 7 or above, it is used for the cultivation of Artemia and Artemia eggs.

[0015] Compared with the prior art, the method for neutralizing brominated brine with the biochemical combination of the present invention has the following advantages:

[0016] (1) The method for neutralizing brominated brine with the biochemical combination of the present invention adopts a treatment method combining chemistry and biology. First, the pH of the brominated brine is adjusted to above 5 by an alkaline substance, and then algae and microorganisms cultured under the same salinity are inoculated. By using the metabolic products of the microorganisms and the photosynthesis of the algae to consume carbon dioxide and affecting the principle of the carbon dioxide - carbonate system, the pH of the brine is increased to above 7, the usage amount of the alkaline substance is limitedly reduced, the post-treatment cost is reduced, and at the same time, the cultivation of algae and microorganisms is realized;

[0017] (2) The method for neutralizing brominated brine with the biochemical combination of the present invention saves the usage amount of the alkaline substance, and moreover, the ecology of the brominated brine is restored by the method of bioremediation during the treatment process. The treated brine can be used for the cultivation of Artemia and Artemia eggs, realizing the comprehensive reuse of the brominated brine. Description of the Drawings

[0018] Figure 1 It is the curve of the relationship between the culture days and pH in Example 1;

[0019] Figure 2 It is the curve of the relationship between the culture days and pH in Example 2;

[0020] Figure 3 It is the relationship curve between the culture days and pH in Example 3. Detailed implementation manners

[0021] Unless otherwise defined, the technical terms used in the following examples have the same meanings as commonly understood by those skilled in the art to which the present invention belongs. The test reagents used in the following examples are all conventional biochemical reagents unless otherwise specified; the experimental methods are all conventional methods unless otherwise specified.

[0022] The present invention will be described in detail below with reference to examples and the accompanying drawings.

[0023] Example 1

[0024] S1. Add magnesium oxide to the bromine-extracted brine with a salinity of 8% and a pH of 2.85, and adjust the pH to 5.08.

[0025] S2. Culture Dunaliella salina with brine having a salinity of 8%.

[0026] S3. Inoculate the cultured Dunaliella salina algal solution into the treated brine, and add nutrient elements such as nitrogen, phosphorus, and potassium required for the growth of salt algae. The density of the inoculated Dunaliella salina is 0.1×10⁴ / ml.

[0027] S4. Detect the pH every 1 day (the results are as Figure 1 shown), and after 14 days, the pH can reach above 7.

[0028] Example 2

[0029] S1. Add magnesium oxide and calcium oxide to the bromine-extracted brine with a salinity of 8% and a pH of 2.85, and adjust the pH to 5.08.

[0030] S2. Culture Dunaliella salina and Rhodotorula rubra with brine having a salinity of 8%.

[0031] S3. Inoculate the cultured Dunaliella salina algal solution and Rhodotorula rubra into the treated brine, and add nutrient elements such as carbon, nitrogen, phosphorus, and potassium sufficient for the growth of microalgae and Rhodotorula rubra. The density of the inoculated Dunaliella salina is 0.1×10⁴ / ml, and the density of Rhodotorula rubra is 1.2×10 6 cfu / ml;

[0032] S4. Detect the pH every 1 day (the results are as Figure 2 shown), and after 12 days, the pH can reach above 7.

[0033] Example 3

[0034] S1. Add magnesium oxide, calcium oxide, and calcium carbonate to the bromine-extracted brine with a salinity of 8% and a pH of 2.85, and adjust the pH to 5.08.

[0035] S2. Cultivate Dunaliella viridis, Chlorella vulgaris and Halophilic archaea with brine of 8% salinity;

[0036] S3. Inoculate the cultivated Dunaliella viridis, Chlorella vulgaris and Halophilic archaea into the treated brine, and add nutrients such as carbon, nitrogen, phosphorus, potassium, etc. sufficient for the growth of Dunaliella viridis, Chlorella vulgaris and Halophilic archaea; the density of inoculated Dunaliella viridis is 0.1×10⁴ / ml, the density of Chlorella vulgaris is 10×10⁴ / ml, and the density of Halophilic archaea is 2.2×10 5 cfu / ml;

[0037] S4. Detect the pH every 1 day (the results are as Figure 3 shown), and the pH can reach above 7 after 16 days.

[0038] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for neutralizing brine with biochemical combination, characterized in that: The steps include: S1. Add alkaline chemicals to the brine after bromine extraction to adjust the pH to 5 or above; S2. Cultivating algae and / or microorganisms using a nutrient solution having the same salinity as the brominated brine; S3, inoculating the algae or microorganisms cultured in S2 into the brine after the pH is adjusted in S1, and adding the nutrient elements required for the growth of the cultured algae or microorganisms; S4. Cultivate until the pH of the brine reaches 7 or above.

2. The method for neutralizing brine with biochemical combination according to claim 1, characterized in that: In S1, the alkaline chemical substance is one or more of sodium hydroxide, calcium hydroxide, calcium oxide, magnesium oxide, and limestone.

3. The method for neutralizing brine with biochemical combination according to claim 1, characterized in that: In S2, the algae are Dunaliella salina, Dunaliella viridis and / or cultured Chlorella vulgaris; and the microorganisms are red yeast and / or halophilic archaea.

4. The method for neutralizing brine with biochemical combination according to claim 1, characterized in that: In S3, the inoculation density of algae is greater than 0.01 ten thousand / ml; the inoculation density of microorganisms is greater than 2×10 5 cfu / ml.

5. The method for neutralizing brine with biochemical combination according to claim 1, characterized in that: In the S3, the nutrient elements are carbon, nitrogen, phosphorus and potassium.

6. The method for neutralizing brine with biochemical combination according to claim 1, characterized in that: In S4, the brine is used for Artemia and Artemia egg culture after the pH value reaches 7 or above.

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