Method for treating soluble organic matter in kelp blanching water

Abstract

The application discloses a kind of kelp blanching water soluble organic matter processing method, belong to kelp processing technical field, steps are as follows: kelp blanching water, kelp residue is mixed with water, filtration zymolysis;Add composite enzyme and carry out zymolysis, and enzyme is killed after zymolysis is completed;Add sodium hydroxide in zymolysis liquid and adjust processing after filtration;Filtering liquid is filtered and adsorbed using diatomite and activated carbon, and pressure microfiltration is carried out;After adding ferric chloride, ultrafiltration is carried out, and ultrafiltration liquid is treated using ion exchange resin after ultrafiltration, and the processing of kelp blanching water is completed.The scheme of the application carries out processing to kelp blanching water, realizes the efficient recovery of soluble organic matter in blanching water, and improves resource recovery rate.The method of the application can reduce the emission of organic matter, and reduce the risk of environmental pollution;Water after processing reaches direct discharge standard.The scheme of the application can recover iodine contained in kelp blanching water, and also can realize the recycling of effective substances such as fucoidan and mannitol.

Description

Technical Field

[0001] This invention relates to the field of kelp processing technology, and more specifically to a method for treating soluble organic matter in kelp blanching water. Background Technology

[0002] The water used to blanch kelp typically refers to the water used to briefly heat kelp in boiling water before cooking (i.e., blanching). This process aims to soften the kelp, remove impurities, salt, and some of the fishy smell from its surface, while preserving as many nutrients as possible.

[0003] The soluble components in kelp blanching mainly include mannitol, fucoidan, iodine, salt, and small amounts of protein. The blanching water contains high levels of salt and impurities, and direct discharge would pollute the environment. Wastewater treatment is necessary, but the process is complex and costly. Although the blanching water contains some useful substances such as iodine, its resource utilization is difficult due to water quality issues. Traditional iodine production processes are not effective in kelp blanching water, which also hinders the development of kelp-related industries.

[0004] Therefore, providing a method for treating soluble organic matter in kelp blanching water to achieve harmless treatment of kelp blanching water is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the present invention provides a method for treating soluble organic matter in the blanching water of kelp.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for treating soluble organic matter in kelp blanching water includes the following steps:

[0008] (1) Take the kelp blanching water and kelp residue, add water to dilute and stir evenly, heat and keep warm, and then process with a wall-breaking machine to obtain a mixed liquid;

[0009] (2) Filter the mixture, add a compound enzyme for enzymatic hydrolysis, and inactivate the enzyme after the enzymatic hydrolysis is completed;

[0010] (3) Add sodium hydroxide to the enzymatic hydrolysate to adjust the pH to 10-12, stir for 20-40 min and let stand for 20-40 min, then filter again to obtain the filtrate;

[0011] (4) The filtrate was sequentially filtered and adsorbed using diatomaceous earth and activated carbon, and the treated solution was subjected to microfiltration under pressure.

[0012] (5) Adjust the pH of the microfiltrate to neutral, add ferric chloride, centrifuge and separate the supernatant and precipitated solid, perform ultrafiltration again, treat the ultrafiltrate with ion exchange resin after ultrafiltration to complete the treatment of kelp blanching water, and discharge the treated water directly or blanch the kelp again.

[0013] Furthermore, the mass ratio of the kelp blanching water, kelp residue and water in step (1) is 1:0.2-0.3:1-3.

[0014] Furthermore, the heating temperature in step (1) is 60-80℃ and the heating time is 2-5h.

[0015] The beneficial effects of adopting the above-mentioned further solution are as follows: the present invention mixes kelp blanching water, kelp residue and water, and after the mixture is treated, more effective ingredients can be incorporated into the water. In subsequent filtration, ultrafiltration and other operations, more organic matter can be retained, which facilitates the subsequent utilization and treatment of the retained organic matter.

[0016] Furthermore, the complex enzyme mentioned in step (2) is a mixture of cellulase and papain;

[0017] The mass ratio of cellulase to papain was 1:1.

[0018] The amount of the compound enzyme added is 0.05%-0.15% of the mass of the mixture.

[0019] Furthermore, in step (2), the enzymatic hydrolysis temperature is 30-45℃ and the enzymatic hydrolysis time is 20-50 min; the enzyme inactivation temperature is 80-90℃ and the enzyme inactivation time is 2-5 min.

[0020] The beneficial effects of adopting the above-mentioned further scheme are as follows: the above scheme can treat the added kelp residue, decompose cellulose and protein, increase the organic matter content of kelp in the enzymatic hydrolysate, and retain more organic matter in subsequent treatment.

[0021] Furthermore, the thickness of the diatomaceous earth in step (4) is 3-8 cm, and the thickness of the activated carbon is 4-6 cm.

[0022] Furthermore, in step (4), the pore size of the microfiltration membrane is 22-45 μm.

[0023] The beneficial effects of adopting the above-mentioned further scheme are that the above scheme can initially retain some organic matter, thereby reducing the time required for subsequent processing and increasing the utilization rate of organic matter in kelp blanching solution.

[0024] Furthermore, the amount of ferric chloride added in step (5) is 0.05%-0.1% of the mass of the microfiltrate.

[0025] Furthermore, the molecular weight cutoff for ultrafiltration in step (5) is 3000-20000 Dalton.

[0026] The beneficial effect of adopting the above-mentioned further solution is that the above operation can remove iodine and most of the organic matter in the solution, so that the purified solution can meet the discharge standards.

[0027] The beneficial effects of this invention are as follows:

[0028] This invention treats kelp blanching water, achieving efficient recovery of soluble organic matter and improving resource recovery rate. The method reduces organic matter emissions, lowering the risk of environmental pollution; the treated water meets direct discharge standards, further protecting the environment. The invention utilizes a combination of diatomaceous earth and activated carbon for filtration and adsorption to recover iodine from the kelp blanching water, followed by ultrafiltration to retain effective substances such as fucoidan and mannitol, thus enabling the treated water to meet direct discharge standards. Detailed Implementation

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] In the embodiments of the present invention, the complex enzymes were all obtained by mixing cellulase and papain in a 1:1 ratio.

[0031] Example 1

[0032] A method for treating soluble organic matter in kelp blanching water:

[0033] (1) Mix the kelp blanching water, kelp residue and water in a mass ratio of 1:0.25:2, heat at 70℃ for 3 hours, and then process with a high-speed blender to obtain a mixed liquid;

[0034] (2) Filter the mixture, add 0.10% compound enzyme and enzymatically hydrolyze at 40℃ for 35 min, and inactivate the enzyme at 90℃ for 3 min after the enzymatic hydrolysis is completed;

[0035] (3) Add sodium hydroxide to the enzymatic hydrolysate to adjust the pH to 11, stir for 30 min and let stand for 30 min, then filter again to obtain the filtrate;

[0036] (4) The filtrate was sequentially filtered and adsorbed using 5cm diatomaceous earth and 5cm activated carbon. The treated solution was then microfiltered using a 22μm microfiltration membrane.

[0037] (5) Adjust the pH of the microfiltrate to neutral, add 0.08% ferric chloride, centrifuge and separate the supernatant and precipitated solid, and perform ultrafiltration again. The molecular weight cutoff of ultrafiltration is 5000-8000 Dalton. After ultrafiltration, treat the ultrafiltrate with ion exchange resin to complete the treatment of kelp blanching water. The treated water is discharged directly.

[0038] Example 2

[0039] A method for treating soluble organic matter in kelp blanching water:

[0040] (1) Mix the kelp blanching water, kelp residue and water in a mass ratio of 1:0.2:1, heat at 80℃ for 2 hours, and then process with a high-speed blender to obtain a mixed liquid;

[0041] (2) Filter the mixture, add 0.05% compound enzyme and enzymatically hydrolyze at 30℃ for 30 min, and inactivate the enzyme at 80℃ for 5 min after the enzymatic hydrolysis is completed;

[0042] (3) Add sodium hydroxide to the enzymatic hydrolysate to adjust the pH to 10, stir for 40 min and let stand for 40 min, then filter again to obtain the filtrate;

[0043] (4) The filtrate was filtered and adsorbed sequentially using 3cm diatomaceous earth and 6cm activated carbon. The treated solution was then microfiltered using a 45μm microfiltration membrane.

[0044] (5) Adjust the pH of the microfiltrate to neutral, add 0.1% ferric chloride, centrifuge and separate the supernatant and precipitated solid, and perform ultrafiltration again. The molecular weight cutoff of ultrafiltration is 15,000-20,000 Dalton. After ultrafiltration, treat the ultrafiltrate with ion exchange resin to complete the treatment of kelp blanching water. The treated water is discharged directly.

[0045] Example 3

[0046] A method for treating soluble organic matter in kelp blanching water:

[0047] (1) Mix the kelp blanching water, kelp residue and water in a mass ratio of 1:0.3:3, heat at 60℃ for 5 hours, and then process with a high-speed blender to obtain a mixed liquid;

[0048] (2) Filter the mixture, add 0.15% compound enzyme and enzymatically hydrolyze at 45℃ for 20 min, and inactivate the enzyme at 90℃ for 2 min after the enzymatic hydrolysis is completed;

[0049] (3) Add sodium hydroxide to the enzymatic hydrolysate to adjust the pH to 12, stir for 20 min and let stand for 30 min, then filter again to obtain the filtrate;

[0050] (4) The filtrate was filtered and adsorbed sequentially using 8cm diatomaceous earth and 4cm activated carbon. The treated solution was then microfiltered using a 22μm microfiltration membrane.

[0051] (5) Adjust the pH of the microfiltrate to neutral, add 0.05% ferric chloride, centrifuge and separate the supernatant and precipitated solid, and perform ultrafiltration again. The molecular weight cutoff of ultrafiltration is 3000-5000 Dalton. After ultrafiltration, treat the ultrafiltrate with ion exchange resin to complete the treatment of kelp blanching water. The treated water is discharged directly.

[0052] Example 4

[0053] A method for treating soluble organic matter in kelp blanching water:

[0054] (1) Mix the kelp blanching water, kelp residue and water in a mass ratio of 1:0.3:2, heat at 75℃ for 4 hours, and then process with a high-speed blender to obtain a mixed liquid;

[0055] (2) Filter the mixture, add 0.12% compound enzyme and enzymatically hydrolyze at 35℃ for 50 min, and inactivate the enzyme at 90℃ for 4 min after the enzymatic hydrolysis is completed;

[0056] (3) Add sodium hydroxide to the enzymatic hydrolysate to adjust the pH to 11, stir for 35 min and let stand for 40 min, then filter again to obtain the filtrate;

[0057] (4) The filtrate was sequentially filtered and adsorbed using 6cm diatomaceous earth and 6cm activated carbon. The treated solution was then microfiltered using a 22μm microfiltration membrane.

[0058] (5) Adjust the pH of the microfiltrate to neutral, add 0.06% ferric chloride, centrifuge and separate the supernatant and precipitated solid, perform ultrafiltration again, the molecular weight cutoff of ultrafiltration is 8000-10000 Dalton, treat the ultrafiltrate with ion exchange resin after ultrafiltration to complete the treatment of kelp blanching water, and discharge the treated water directly.

[0059] Comparative Example 1

[0060] The scheme is the same as that in Example 1, except that no enzymatic hydrolysis was performed.

[0061] Comparative Example 2

[0062] The scheme is the same as that in Example 1, except that only diatomaceous earth is used for treatment.

[0063] Comparative Example 3

[0064] The scheme is the same as that in Example 1, except that only activated carbon is used for treatment.

[0065] Test case

[0066] The same batch of kelp blanching water was treated using the methods of Examples 1-4 and Comparative Examples 1-3, and the treatment results are shown in Table 1.

[0067] Table 1

[0068] project COD (mg / L) pH value Suspended solids (mg / L) initial value 513 6.2 105 Example 1 55 6.4 <1 Example 2 62 6.3 <1 Example 3 57 6.2 <1 Example 4 60 6.5 <1 Comparative Example 1 125 7.1 12 Comparative Example 2 136 7.2 22 Comparative Example 3 143 6.8 18

[0069] Experimental results show that the solution of the present invention can effectively treat kelp blanching water, reduce its COD and suspended solids content, thereby achieving the separation and treatment of soluble organic matter in kelp blanching water.

[0070] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for treating soluble organic matter in kelp blanching water, characterized in that, Includes the following steps: (1) Take the kelp blanching water and kelp residue, add water to dilute and stir evenly, heat and keep warm, and then process with a wall-breaking machine to obtain a mixed liquid; (2) Filter the mixture, add a compound enzyme for enzymatic hydrolysis, and inactivate the enzyme after the enzymatic hydrolysis is completed; (3) Add sodium hydroxide to the enzymatic hydrolysate to adjust the pH to 10-12, stir for 20-40 min and let stand for 20-40 min, then filter again to obtain the filtrate; (4) The filtrate was sequentially filtered and adsorbed using diatomaceous earth and activated carbon, and the treated solution was subjected to microfiltration under pressure. (5) Adjust the pH of the microfiltrate to neutral, add ferric chloride, centrifuge and separate the supernatant and precipitated solid, perform ultrafiltration again, treat the ultrafiltrate with ion exchange resin after ultrafiltration to complete the treatment of kelp blanching water, and discharge the treated water directly or blanch the kelp again.

2. The method for treating soluble organic matter in kelp blanching water according to claim 1, characterized in that, The mass ratio of the kelp blanching water, kelp residue and water in step (1) is 1:0.2-0.3:1-3.

3. The method for treating soluble organic matter in kelp blanching water according to claim 1, characterized in that, The heating and heat preservation temperature in step (1) is 60-80℃, and the heating time is 2-5h.

4. The method for treating soluble organic matter in kelp blanching water according to claim 1, characterized in that, The complex enzyme mentioned in step (2) is a mixture of cellulase and papain; The amount of the compound enzyme added is 0.05%-0.15% of the mass of the mixture.

5. A method for treating soluble organic matter in kelp blanching water according to claim 1 or 4, characterized in that, The enzymatic hydrolysis temperature in step (2) is 30-45℃ and the enzymatic hydrolysis time is 20-50 min; the enzyme inactivation temperature is 80-90℃ and the enzyme inactivation time is 2-5 min.

6. The method for treating soluble organic matter in kelp blanching water according to claim 1, characterized in that, The thickness of the diatomaceous earth in step (4) is 3-8 cm, and the thickness of the activated carbon is 4-6 cm.

7. The method for treating soluble organic matter in kelp blanching water according to claim 1, characterized in that, The pore size of the microfiltration membrane in step (4) is 22-45 μm.

8. The method for treating soluble organic matter in kelp blanching water according to claim 1, characterized in that, The amount of ferric chloride added in step (5) is 0.05%-0.1% of the mass of the microfiltrate.

9. The method for treating soluble organic matter in kelp blanching water according to claim 1, characterized in that, The ultrafiltration in step (5) is performed using an ultrafiltration membrane with a molecular weight cutoff of 3000-20000 Dalton.