Method for preparing eco-friendly fertilizer by using by-product produced during starfish extraction, and eco-friendly fertilizer prepared thereby

Abstract

The present invention relates to a method for preparing an eco-friendly fertilizer by using a by-product produced during starfish extraction, and an eco-friendly fertilizer prepared thereby. According to the present invention, the eco-friendly liquid fertilizer can be prepared through a simple process by using waste liquid remaining after solids are collected from starfish protein hydrolysates. The fertilizer according to the present invention has an excellent composition of organic matter and nitrogen-phosphate-potassium (NPK) and exhibits growth-promoting activity due to starfish-derived organic matter, and thus, if the fertilizer of the present invention is used during crop cultivation, the quality and yield of crops can be effectively improved.

Description

Method for manufacturing an eco-friendly fertilizer using by-products generated in the starfish extraction process and eco-friendly fertilizer manufactured thereby

[0001] The present invention relates to a method for manufacturing an eco-friendly fertilizer using a by-product generated in a starfish extraction process and to an eco-friendly fertilizer manufactured thereby, and more particularly, to a method for manufacturing an eco-friendly liquid fertilizer with excellent crop growth performance through a simple process using a by-product generated in a starfish extraction process and to an eco-friendly fertilizer manufactured thereby.

[0002] Fertilizers are nutrients that enhance soil productivity and promote plant growth. With the rapid development of industry and population growth, food demand has increased, leading to a rapid expansion in the use of pesticides and chemical fertilizers to enhance productivity.

[0003] However, chemical fertilizers and pesticides have raised concerns about soil acidification, reduced fertility, and toxicity. They also have the disadvantage of causing resistance and soil microbial degradation. Due to these issues, farming methods that utilize high-quality organic fertilizers instead of chemical fertilizers and pesticides are being developed.

[0004] For example, Korean Patent Publication No. 10-2630801 relates to an environmentally friendly crop fertilizer composition containing fermented perilla seeds as an active ingredient and a method for cultivating crops using the same, and states that the use of fermented perilla seeds exhibits excellent sterilization, insecticidal, and crop nutritional effects.

[0005] In addition, Korean Patent Publication No. 10-2479161 relates to a method for manufacturing an eco-friendly fertilizer using spent mushroom substrate, and describes a method for manufacturing fertilizer by fermenting hay, straw, livestock manure, etc. with microorganisms and recovering and fermenting the spent mushroom substrate.

[0006] However, in the case of the above technologies, the use of food or long-term fermentation is required for the production of fertilizers. If a fertilizer that can be simply manufactured without a fermentation process using eco-friendly waste is developed, it is expected that the productivity and eco-friendliness of fertilizers can be further increased.

[0007] In this situation, the inventors of the present invention discovered that an environmentally friendly fertilizer with excellent performance can be obtained through a simple process by using a by-product (waste liquid) generated in the process of manufacturing an environmentally friendly deicing agent, a porous structure of sea squirt, from sea squirt, and completed the present invention.

[0008] The purpose of the present invention is to provide a method for producing an eco-friendly liquid fertilizer through a simple process using by-products generated in the process of extracting starfish.

[0009] Another object of the present invention is to provide an environmentally friendly liquid fertilizer having excellent crop growth performance manufactured by the above method.

[0010] In order to achieve the above object, the present invention provides a method for producing an eco-friendly fertilizer, comprising the steps of: immersing starfish in an alkaline solution to decompose proteins; collecting solids from the decomposed product and obtaining the remaining waste liquid; and neutralizing the waste liquid by adding acid to produce fertilizer.

[0011] In the present invention, the concentration of the alkaline solution may be 5 to 30 wt%.

[0012] In the present invention, the alkaline solution may include potassium hydroxide (KOH) or sodium hydroxide (NaOH).

[0013] In the present invention, after the protein decomposition step using the alkaline solution, a step of decomposing the protein by adding protease can be further performed.

[0014] In the present invention, the acid may include at least one selected from the group consisting of phosphoric acid, nitric acid, and acetic acid.

[0015] In the present invention, the amount of the acid may be 5 to 30 parts by volume per 100 parts by volume of the alkaline solution.

[0016] In the present invention, after the neutralization step, a step of adding a nitrogen-phosphate-potassium (NPK) source can be further performed.

[0017] In the present invention, the NPK source may include at least one selected from the group consisting of urea, potassium triphosphate, potassium nitrate, and ammonium nitrate.

[0018]

[0019] The present invention also provides an eco-friendly fertilizer manufactured using the above method.

[0020] According to the present invention, an eco-friendly liquid fertilizer can be manufactured through a simple process by collecting solids from protein decomposition products of starfish and using the remaining waste liquid. The fertilizer according to the present invention has excellent organic matter and nitrogen-phosphate-potassium (NPK) composition and exhibits growth-promoting activity of starfish-derived organic matter. Therefore, when the fertilizer of the present invention is used in crop cultivation, the quality and yield of the crop can be effectively improved.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In general, the nomenclature used herein is well known and commonly used in the art.

[0022]

[0023] The present invention relates to a method for manufacturing an eco-friendly fertilizer using by-products generated in a starfish extraction process, and to an eco-friendly fertilizer manufactured thereby and containing organic matter derived from starfish.

[0024] According to the present invention, an eco-friendly liquid fertilizer can be manufactured through a simple process by collecting solids from protein decomposition products of starfish and using the remaining waste liquid. The fertilizer according to the present invention has excellent organic matter and nitrogen-phosphate-potassium (NPK) composition and exhibits growth-promoting activity of starfish-derived organic matter. Therefore, when the fertilizer of the present invention is used in crop cultivation, the quality and yield of the crop can be effectively improved.

[0025] In the present invention, the eco-friendly fertilizer containing the organic matter derived from starfish can be manufactured through the steps of: immersing starfish in an alkaline solution to decompose proteins; collecting solids from the decomposed product and obtaining the remaining waste liquid (byproduct); and neutralizing the waste liquid by adding acid.

[0026] According to the present invention, when a starfish is immersed in an alkaline solution, a porous structure of the starfish can be obtained and effective organic substances derived from the starfish can be extracted at the same time.

[0027] In the present invention, the alkaline solution may be a potassium hydroxide (KOH) solution or a sodium hydroxide (NaOH) solution. The alkaline solution may have a concentration of 5 to 30 wt%, preferably 15 to 30 wt%, for example 15 to 25 wt%. More preferably, the alkaline solution may have a concentration of 20 to 30 wt%.

[0028] Depending on the concentration of the alkaline solution added in the above step, the concentration of organic matter in the extracted fertilizer can be controlled. If the concentration of the alkaline solution is lower than the above range, the process time may increase and the organic matter content may decrease. If the concentration of the alkaline solution is higher than the above range, the phase stability of the fertilizer may decrease.

[0029] In relation to this, in the embodiment of the present invention, when the concentration of the alkaline solution is 1 or 3 wt%, the protein decomposition process of starfish does not proceed smoothly, the content of organic matter is also low, and when the concentration is high at 35 wt%, phase separation occurs even when a large amount of dispersant is added, whereas when the concentration is 5 to 30 wt%, protein decomposition occurs smoothly, and phase separation does not occur even when the organic matter content is high, and when the concentration is 15 wt% or higher (20 or 30 wt%), the process time is greatly shortened, and it is confirmed that the NPK and organic matter content are high.

[0030] In the present invention, the alkaline solution immersion step can be performed for 2 to 18 hours, preferably 6 to 12 hours.

[0031] In one embodiment of the present invention, after the protein decomposition step (first protein decomposition step) using the alkaline solution, a step (second protein decomposition step) of decomposing the protein using a protease (protein decomposition enzyme) may be further performed. This allows for the extraction of organic matter adhered within the bone fragments that are not treated with the alkaline solution.

[0032] In the present invention, one or more types of proteases such as pepsin, trypsin, and peptidase can be used.

[0033] In the present invention, the protein decomposition process generates solids and byproducts. The solids, which are porous structures derived from starfish, can be collected and used for purposes such as deicing agents. During this process, a liquid byproduct (waste liquid) remains.

[0034] The present invention utilizes the by-product generated in the above-mentioned starfish extraction process, and organic matter derived from starfish is extracted through alkaline treatment, which can be used as a fertilizer that can effectively promote crop growth.

[0035] Specifically, proteins are decomposed from starfish through immersion in an alkaline solution, the solids are collected, and the remaining waste liquid is obtained. Then, an acid is added to the waste liquid to neutralize it.

[0036] By adding acid in the neutralization step, the nitrogen (N)-phosphate (P)-potassium (K) content, which is an important indicator of compound fertilizer, can be improved, and the pH can be adjusted to 7.0 to 9.0, preferably 7.5 to 8.5.

[0037] In the present invention, the acid used for neutralization may be at least one of phosphoric acid, nitric acid, and acetic acid. The amount of acid added for neutralization may be 5 to 30 parts by volume per 100 parts by volume of the alkaline solution, and the amount of acid may be adjusted in proportion to the concentration of the alkaline solution.

[0038] In one embodiment of the present invention, a step of adding a nitrogen-phosphate-potassium source (NPK source) after neutralization can be further performed, thereby further improving the organic matter and NPK content. The NPK source may be one or more of urea, tripotassium phosphate, potassium nitrate, sodium nitrate, or ammonium nitrate.

[0039] In the present invention, after the neutralization step and before the NPK source addition step, an additive addition step may be further performed to improve the characteristics of the fertilizer. For example, one or more additives such as a defoaming agent to prevent foaming, a deodorizing agent to suppress odor generation, and a dispersing agent to prevent sedimentation may be added. Each additive may be added independently or together.

[0040] By collecting the solid content from the protein decomposition product of starfish and neutralizing the remaining waste liquid according to the process of the present invention described above, an eco-friendly liquid fertilizer containing starfish-derived organic matter and having an excellent NPK composition can be manufactured.

[0041] NPK composition refers to the composition of nitrogen (N), phosphorus (P), and potassium (K). Nitrogen produces chlorophyll, which is involved in photosynthesis, and plays a role in the growth of stems, leaves, and size of crops. Phosphorus promotes the growth of branches and leaves and plays an important role in carbohydrate metabolism. In addition, potassium suppresses rapid changes in pH and plays a role in carbohydrate metabolism, respiration, photosynthesis, protein synthesis, chlorophyll production, and strengthens roots and stems.

[0042] The eco-friendly liquid fertilizer manufactured according to the present invention has an excellent NPK composition and organic matter content. For example, the liquid fertilizer of the present invention may have a total nitrogen (N) content of 0.3 to 2.0%, a water-soluble phosphate (P) content of 2.0 to 8.0%, and a water-soluble potassium (K) content of 1.0 to 10.0%. Additionally, the organic matter content may be 5.0 to 15.0%.

[0043] When applied during crop cultivation, the liquid fertilizer according to the present invention provides favorable conditions for root and leaf growth and photosynthesis, promoting not only crop growth but also the smooth movement of nutrients, thereby improving crop quality and yield. Furthermore, the fertilizer's NPK composition, as well as the unique properties of the organic matter derived from starfish, can further promote crop growth.

[0044]

[0045] Example

[0046]

[0047] The present invention is described in more detail through the following examples. However, these examples are provided to illustrate some experimental methods and compositions for the purpose of illustratively explaining the present invention, and the scope of the present invention is not limited to these examples.

[0048]

[0049] Manufacturing example: Manufacturing of eco-friendly liquid fertilizer containing organic matter derived from starfish

[0050]

[0051] Liquid fertilizer was manufactured using the waste liquid remaining after alkaline treatment of starfish.

[0052] First, frozen starfish raw material was thawed and placed in a stirred tank. The starfish was immersed in an alkaline solution (KOH solution) and decomposed for 12 hours. The solid matter was collected to obtain waste liquid (byproduct).

[0053] Phosphoric acid was added to the above waste liquid to neutralize it to a pH of 7.5 to 8.5, then transferred to a reaction tank and a defoaming agent was added to prevent foaming. After adding an odor removing agent to the reaction tank, a dispersing agent was added to ensure phase stability of the organic components, thereby producing an eco-friendly liquid fertilizer containing organic substances derived from starfish.

[0054] By applying the conditions of Table 1 below to the method of the above manufacturing example, liquid fertilizers of Examples 1-1 to 1-5 and Comparative Examples 1-1 to 1-3 were manufactured, and the characteristics of the process and products were analyzed.

[0055]

[0056] Classification KOH solution concentration (wt%)Input amount Starfish (kg)KOH Solution (L) Phosphoric acid (L) Antifoaming agent (ppm) Dispersing agent (ppm) Example 1-15 2000 1000 50 200 500 Example 1-2 10 2000 1000 100 200 1000 Example 1-3 12.5 2000 1000 125 200 1250 Example 1-4 2000 1000 200 200 2000 Example 1-5 30 2000 1000 300 200 3000 Comparative Example 1-1 1 2000 1000 10200 100 Comparative Example 1-2 3 2000 1000 30200 300 Comparative Example 1-3 3 5 2000 1000 350 200 3500

[0057]

[0058] Experimental Example 1: Analysis of the time required for the first decomposition process

[0059]

[0060] In the first decomposition process of the manufacturing example, the time required for decomposition to a level that can be transferred from the stirring tank to the reaction tank was measured in 1-hour units and is shown in Table 2 below.

[0061]

[0062] Time required for classification process (h) Example 1-172 Example 1-240 Example 1-321 Example 1-413 Example 1-511 Comparative Example 1-1 Decomposition X Comparative Example 1-2 Decomposition X Comparative Example 1-312

[0063]

[0064] Experimental results showed that when the concentration of the alkaline solution was 1 or 3 wt%, the primary decomposition process of starfish did not proceed smoothly, whereas when the concentration was 5 wt% or higher, the primary decomposition process proceeded smoothly. Accordingly, it was confirmed that it is preferable to adjust the concentration of the alkaline solution to 5 wt% or higher when applying the present invention.

[0065]

[0066] Experimental Example 2: Analysis of NPK and organic matter content in liquid fertilizer

[0067]

[0068] For the liquid fertilizer of the manufacturing example, the NPK content (%) and organic matter content (%) were measured and the results are shown in Table 3 below.

[0069]

[0070] Classification N (total nitrogen) P (soluble phosphate) K (soluble potassium) Organic Example 1-11.122.691.749.77 Example 1-20.943.43.47.16 Example 1-30.514.113.268.82 Example 1-40.765.045.4413.48 Example 1-51.436.987.8110.3 Comparative Example 1-10.181.090.590.47 Comparative Example 1-20.781.831.132.19 Comparative Example 1-30.896.818.3612.53

[0071]

[0072] Experimental results showed that when the alkali concentration was less than 5 wt%, starfish did not decompose well, resulting in a low organic matter content within the fertilizer solution. Conversely, when the alkali concentration was 5 wt% or higher, the fertilizer's NPK content and organic matter content were high.

[0073]

[0074] Experimental Example 3: Phase Stability Analysis of Liquid Fertilizers

[0075]

[0076] When manufacturing a liquid fertilizer according to the manufacturing example, whether phase separation occurred in the solution after 12 hours of stirring was observed, and the results are shown in Table 4 below.

[0077]

[0078] Whether or not separation occurs in the classificationExample 1-1XExample 1-2XExample 1-3XExample 1-4XExample 1-5XComparative Example 1-1XComparative Example 1-2XComparative Example 1-3O

[0079]

[0080] Experimental results showed that phase stability was excellent when the alkali concentration was 1 to 30 wt%. However, when the concentration exceeded 30 wt%, phase separation was observed even when a large amount of dispersant was added. Accordingly, it was found that it was desirable to control the concentration of the alkali solution to 30 wt% or less to prevent phase separation.

[0081]

[0082] Experimental Example 4: Crop Cultivation Test Using Fertilizer

[0083]

[0084] Common chemical fertilizers and commercially available products manufactured to have the same NPK and organic matter content as the liquid fertilizer manufactured using the present invention were used in crop cultivation, and the results were compared. The NPK and organic matter contents of the liquid fertilizers used in the experiment are shown in Table 5 below.

[0085]

[0086] Classification N (total nitrogen) (%) P (soluble phosphate) (%) K (soluble potassium) (%) Organic matter (%) Example 1-40.765.045.4413.48 Comparative Example 2-10.815.345.290 Comparative Example 2-2 Commercial organic fertilizer: Syngenta's plant-based amino acid fertilizer "Isbang"

[0087]

[0088] 4-1. Potato cultivation test

[0089]

[0090] The above liquid fertilizer was applied to potato cultivation and the growth characteristics of the cultivated potatoes were confirmed.

[0091] Potatoes were planted at 30 cm intervals on April 10, 2022, and fertilizer was applied three times per week, including foliar and irrigation treatments. All potatoes were harvested on July 20, 2022, and growth characteristics such as weight, yield, diameter, chlorophyll, and chlorophyll content were measured. The results are shown in Table 6 below.

[0092]

[0093] ClassificationWeight (g / unit)Yield (No. / plant)Diameter (mm)Chlorophyll (SPAD)Comparative (0-5)Example 1-4185.58.777.0936.150Comparative Example 2-1184.98.597.0336.020Untreated group181.48.26.7535.850

[0094]

[0095] As a result of the experiment, when the liquid fertilizer according to the present invention was applied to potato cultivation, the weight, yield, diameter, and chlorophyll content increased compared to the untreated group. In the case of yield per plant (plant), the standard amount treatment group showed a maximum increase of 6.95% compared to the untreated group. In addition, when the presence or absence of a difference in potato crops due to fertilization with starfish compound fertilizer was investigated, no difference was observed in the standard amount and double amount treatment groups at 7, 14, and 21 days after treatment.

[0096] Accordingly, it was confirmed that when the liquid fertilizer of the present invention is used during potato cultivation, the quality and yield of potatoes are improved.

[0097]

[0098] 4-2. Cabbage cultivation test

[0099]

[0100] Each liquid fertilizer was applied to cabbage cultivation and the growth characteristics of the cultivated cabbage were confirmed.

[0101] On April 22, 2022, the cabbages were transplanted at 30 cm intervals every week, and fertilizer was applied three times per week through foliar and irrigation treatments. All cabbages were harvested on June 13, 2022, and growth characteristics such as weight, yield, diameter, chlorophyll, and chlorophyll content were measured. The results are shown in Table 7 below.

[0102]

[0103] Classification Fresh weight (kg / plant) Circumference (cm) Leaf length (cm) Leaf width (cm) Chlorophyll (SPAD) Comparative (0-5) Example 1-4 3.06 7 1.73 3.32 23.52 37.50 Comparative Example 2-12.92 69.13 3.22 3.43 37.60 Untreated group 2.76 7.32 28.95 21.95 35.30

[0104]

[0105] As a result of the experiment, fresh weight, which is an indicator of cabbage yield, was the highest in the liquid fertilizer treatment group of the present invention, and the circumference, leaf length, and leaf width were also measured to be the largest. When chlorophyll was measured in the middle part of the longest leaf of the cabbage in triplicate, the fertilizer treatment group showed a higher chlorophyll content than the untreated group, and no difference due to fertilizer was observed.

[0106] Accordingly, it was confirmed that when the liquid fertilizer of the present invention is used in cabbage cultivation, the quality and yield of cabbage are improved.

[0107]

[0108] 4-3. Cabbage cultivation test

[0109]

[0110] Each liquid fertilizer was applied to cabbage cultivation and the growth characteristics were confirmed.

[0111] The experiment was conducted by transplanting cabbage seedlings, and a total of four treatment processes were performed. Specifically, conventional fertilizer and clean water were used as Control Group 1, and conventional fertilizer and Isebang (125 mL / seedling) were used as Control Group 2. The results were compared with the results obtained by treating conventional fertilizer and a 1,000-fold dilution of the liquid fertilizer according to the present invention (Example 1-4).

[0112] Sowing on August 1, 2022, the plants were grown in 72-hole trays in a peat:vermiculite substrate with a volume ratio of 3:1. When the seedlings had grown to 4 to 6 leaves, they were transplanted to the experimental area, and fertilization was applied three times in total: 15 days (September 23), 30 days (October 11), and 46 days (October 27) after transplanting. Other cultivation management measures were the same, and after harvesting the cabbage on November 21, production was measured and growth indices such as plant height (cm) and spread (cm) were checked. The results are shown in Table 8 below.

[0113]

[0114] Plant height (cm) Spread (cm) Single leaf chlorophyll (SPAD) Root length (cm) Plant weight (kg) Example 1-4 34.426 1.5 16.55 4.8 19.05 2.15 Comparative Example 2-2 30.75 60 15.67 47.08 19.86 2.2 Untreated group 33.3 358 165 1.88 16.14 1.95

[0115]

[0116] According to the present invention, the liquid fertilizer containing organic matter derived from starfish not only showed superior growth results compared to the test group (untreated group) that was not treated with fertilizer, but also showed superior growth results compared to the chemical fertilizer having the same NPK composition.

[0117] According to the above experimental results, it was found that the organic matter derived from starfish exhibited superior functions due to its material specificity beyond the characteristics of NPK composition.

[0118]

[0119] From the above description, those skilled in the art will understand that the present invention can be implemented in other specific forms without altering its technical concept or essential characteristics. In this regard, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of the present invention should be interpreted as encompassing all changes or modifications derived from the meaning and scope of the following claims and their equivalent concepts, rather than the detailed description above.

Claims

1. Step of immersing starfish in an alkaline solution to break down proteins; A step of collecting the solid content from the above decomposition product and obtaining the remaining waste liquid; and A step of manufacturing fertilizer by neutralizing the waste liquid by adding acid to it. A method for manufacturing an eco-friendly fertilizer, comprising: A method for producing an eco-friendly fertilizer, wherein the concentration of the alkaline solution is 5 to 30 wt%.

2. In paragraph 1, A method for producing an environmentally friendly fertilizer, wherein the alkaline solution contains potassium hydroxide (KOH) or sodium hydroxide (NaOH).

3. In paragraph 1, After the protein decomposition step using the above alkaline solution, A method for manufacturing an environmentally friendly fertilizer, further comprising a step of decomposing protein by adding protease.

4. In paragraph 1, A method for producing an environmentally friendly fertilizer, wherein the acid comprises at least one selected from the group consisting of phosphoric acid, nitric acid, and acetic acid.

5. In paragraph 1, A method for producing an environmentally friendly fertilizer, wherein the amount of the acid is 5 to 30 parts by volume per 100 parts by volume of the alkaline solution.

6. In paragraph 1, After the above neutralization step, A method for producing an environmentally friendly fertilizer, further comprising a step of adding a nitrogen-phosphate-potassium (NPK) source.

7. In paragraph 6, A method for producing an environmentally friendly fertilizer, wherein the NPK source comprises at least one selected from the group consisting of urea, potassium triphosphate, potassium nitrate, and ammonium nitrate.

8. An environmentally friendly fertilizer manufactured using any one of the methods of paragraphs 1 to 7.