KR102281445B1 - Organic waste recycling method and organic matter produced thereof - Google Patents

Abstract

The organic waste resource conversion method of the present invention and the organic material produced through the method protect the environment by preventing the inflow of leachate generated during the treatment of various water-containing organic wastes such as livestock waste, food waste, and sewage sludge into the environment, and At the same time, it has the effect of effectively removing the peculiar odor of organic waste.
In addition, the organic waste recycling method of the present invention and the organic material produced through the method perform a multi-step neutralization reaction and exothermic reaction using the water-containing organic waste, thereby providing an organic material that can be used as a raw material for a weakly basic to neutral fertilizer or feed. At the same time, there is an effect that can be effectively used as a raw material for sterilized fertilizer or feed due to high reaction heat.

Description

Organic waste recycling method and organic matter manufactured through the method {ORGANIC WASTE RECYCLING METHOD AND ORGANIC MATTER PRODUCED THEREOF}

The present invention relates to a method for recycling organic waste and organic matter produced through the method, and more particularly, by converting various water-containing organic wastes such as livestock waste, food waste, sewage sludge, etc. into resources to produce organic raw materials, which can be used as feed or fertilizer. And, it relates to a method for recycling organic waste that can protect the environment by preventing the inflow of leachate, etc. generated during the processing of organic waste, and to an organic material manufactured through the method.

Organic matter, which accounts for the largest portion of human resources, is generated by being transformed into organic waste through consumption activities. Organic waste is one of the serious environmental pollution problems. Organic waste includes organic components among household waste, human excreta and livestock manure, sewage sludge, agro-industrial waste, agricultural and forestry waste, and the like. Since these wastes have a huge impact on the environment due to their high load on organic matter, interest in the treatment of organic wastes is increasing. In the past, the disposal of organic wastes has depended on landfilling and incineration, but landfilling is prohibited by the Waste Management Act, so there is an urgent need to develop and secure technologies for efficient treatment.

In addition, in recent years, we are facing the problem of depletion of fossil fuels and environmental problems caused by their use, and it is urgent to secure technology such as securing an alternative energy source called new and renewable energy as a countermeasure against this. Therefore, there is a high interest in research and development of technology for anaerobic digestion process that treats organic waste and generates renewable energy as a by-product.

Among the biological treatment processes of organic wastes, the anaerobic treatment method consumes less energy, converts it to useful gas, has the ability to decompose high-concentration organic compounds, and reduces surplus sludge to prevent environmental pollution compared to other biological or physical and chemical treatment processes. Considering the aspect and the recycling of energy from waste, it can be a very desirable waste treatment process.

However, in the anaerobic digestion process of organic waste, leachate is generated, which causes environmental pollution that damages soil and water quality, and it is difficult to recycle due to the odor from the gas.

In this regard, Korean Patent No. 10-1447073 discloses an anaerobic treatment method of organic sludge. However, even in this case, the heat of reaction is still not sufficiently generated to dry all of the leachate, the odor from the gas is not completely removed, and after the neutralization reaction, fertilizer, animal feed, etc. There was a limitation in that it was difficult to use as an organic raw material.

Korean Patent Registration 10-1447073

The present invention has been devised to solve the above-mentioned problems, and the first object to be solved by the present invention is to protect the environment by preventing the inflow of leachate generated during the processing of organic waste into the environment, and to prevent odor peculiar to organic waste. It is to provide a method for recycling organic waste that can effectively remove

The second problem to be solved by the present invention is to provide an organic waste resource recycling method that can effectively utilize various organic wastes without environmental pollution by manufacturing a raw material for a weak base to neutral fertilizer or feed using organic waste, and an organic material manufactured through this method will do

The present invention in order to solve the above problems, the present invention comprises the steps of (1) adding a mixed desiccant to organic waste to produce an intermediate product through a lime stabilization reaction; and (2) _{adding carbon dioxide (CO 2} ) to the intermediate product to obtain a final product of pH 7 to 9 through a neutralization reaction; provides an organic waste recycling method comprising.

According to a preferred embodiment of the present invention, the mixed desiccant may include quicklime and an oxidizing agent.

According to a preferred embodiment of the present invention, the oxidizing agent is sodium percarbonate (2Na ₂ CO ₃ ·3H ₂ O ₂ ), potassium permanganate (KMnO ₄ ), chlorine dioxide (ClO ₂ ), ozone (O ₃ ), hydrogen peroxide (H) ₂ 0 ₂ ) and hypochlorous acid (HClO) may include any one or more selected from the group consisting of.

According to a preferred embodiment of the present invention, the mixed desiccant may include 10 to 200 parts by weight of an oxidizing agent based on 100 parts by weight of quicklime.

According to a preferred embodiment of the present invention, the mixed desiccant may further include 10 to 400 parts by weight of a coagulant based on 100 parts by weight of quicklime.

According to a preferred embodiment of the present invention, the coagulant is aluminum sulfate (Al ₂ (SO ₄ ) ₃ ·14H ₂ O), iron sulfate (Fe ₂ (SO ₄ ) ₃ ·7H ₂ O), aluminum ammonium sulfate (AlH) ₄ NO ₈ S ₂ ·12H ₂ O), iron chloride (FeCl ₃ ), potassium aluminum sulfate (AlKO ₈ S2·12H ₂ O), sodium aluminate (Na ₂ O·Al ₂ O ₃ ), sodium silicate (Na ₂ O) ·SiO ₂ ) and may be any one or more selected from the group consisting of bentonite.

According to a preferred embodiment of the present invention, both of the following conditions (a) and (b) may be satisfied.

(a)

(b)

(Wx: moisture content of organic waste, Wy: moisture content of the first intermediate product, Wz: moisture content of final product)

In addition, the present invention provides an organic material prepared by any one of the above methods.

Furthermore, the present invention provides a feed containing the organic material as a raw material.

The organic waste resource conversion method of the present invention and the organic material produced through the method protect the environment by preventing the inflow of leachate generated during the treatment of various water-containing organic wastes such as livestock waste, food waste, and sewage sludge into the environment, and At the same time, it has the effect of effectively removing the peculiar odor of organic waste.

In addition, the organic waste recycling method of the present invention and the organic material produced through the method perform a multi-step neutralization reaction and exothermic reaction using the water-containing organic waste, thereby providing an organic material that can be used as a raw material for a weakly basic to neutral fertilizer or feed. At the same time, there is an effect that can be effectively used as a raw material for sterilized fertilizer or feed due to high reaction heat.

1 is a process step diagram for a method for recycling organic waste according to a preferred embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily carry out the present invention.

As described above, the conventional organic waste treatment method does not generate enough heat of reaction to dry all of the large amount of leachate, making it difficult to completely block the inflow into the environment. was difficult to recycle as organic raw materials such as fertilizer and feed. In addition, when the neutralization reaction is performed, there is a difficulty in that it cannot be used as a raw material for fertilizer or animal feed due to high basicity.

Accordingly, the present invention comprises the steps of (1) adding a mixed desiccant to organic waste to produce an intermediate product through a lime stabilization reaction; and (2) _{adding carbon dioxide (CO 2} ) to the intermediate product to obtain a final product having a pH of 7 to 9 through a neutralization reaction. .

Accordingly, it is possible to protect the environment by preventing the inflow of leachate generated during the treatment of various aqueous organic wastes, such as livestock waste, food waste, and sewage sludge, into the environment, and at the same time effectively remove the peculiar odor of organic waste. It works. In addition, by performing a multi-step neutralization reaction and exothermic reaction, an organic material that can be used as a raw material for a weak basic to neutral fertilizer or feed can be provided, and at the same time, a sterilized organic material can be provided by effectively removing bacteria, etc. due to the high reaction heat. there is an effect

1 is a process step diagram of a feed manufacturing method using organic waste according to a preferred embodiment of the present invention. Referring to FIG. 1 , an intermediate product is generated through a lime stabilization reaction by adding a mixed desiccant to various organic wastes (S1). When carbon dioxide (CO ₂ ) is added to the intermediate product, a neutralization reaction occurs, thereby obtaining a final product (S2). The final product is a neutral to weakly basic organic material having a pH of 7 to 9, which can be used as an organic raw material such as fertilizer or feed.

As such, the present invention performs the lime stabilization reaction and the neutralization reaction step by step. Through this, the present invention can dry the water-containing organic waste with high reaction heat, and there is an effect that can completely sterilize bacteria and the like contained therein. In addition, by performing the neutralization reaction in stages, the pH of the final product can be adjusted to pH 7 to 9, which has the advantage of being usefully used as an organic raw material such as fertilizer or animal feed.

First, the step (S1) of generating a first intermediate product through a lime stabilization reaction by adding a mixed desiccant to (1) organic waste will be described.

Organic waste refers to water-containing organic waste materials such as livestock waste, food waste, and sewage sludge. Since it contains a large amount of moisture, it can broadly mean organic waste materials that require moisture removal in order to be recycled into useful organic substances. At this time, the moisture content of the organic waste may be 80 to 90%.

The mixed desiccant may mean a material that can be added to organic waste to dry moisture through a lime stabilization reaction, and according to a preferred embodiment of the present invention, the mixed desiccant may include quicklime (CaO).

When the mixed desiccant is added to the organic waste as described above, the lime stabilization reaction according to the following Reaction Formula 1 occurs.

[Scheme 1]

CaO + H ₂ O → Ca(OH) ₂ , ΔH < 0

Referring to Scheme 1, water (H ₂ O) is moisture contained in organic waste. That is, when the moisture contained in the organic waste reacts with quicklime (CaO), an exothermic reaction of lime stabilization occurs and dihydrate is generated, and a dried intermediate product can be obtained by removing moisture from the organic waste.

As such, quicklime (CaO) absorbs moisture contained in organic waste, and can dry leachate generated during the organic waste treatment process. Accordingly, it is possible to block the inflow of moisture from the leachate into the surrounding environment, thereby preventing water and soil contamination. In addition, organic wastes can be dried by absorbing moisture from the leachate, and organic substances containing nutrients such as N, P, and Ca can be produced as they are.

In addition, according to a preferred embodiment of the present invention, the mixed drying agent may further include an oxidizing agent. In this case, a basic intermediate product may be produced by neutralization by the oxidizing agent.

As the oxidizing agent, a wide range of compounds capable of neutralizing organic wastes can be used. According to a preferred embodiment of the present invention, the oxidizing agent is sodium percarbonate (2Na ₂ CO ₃ ·3H ₂ O ₂ ), potassium permanganate (KMnO ₄ ), chlorine dioxide (ClO ₂ ), ozone (O ₃ ), hydrogen peroxide (H) ₂ 0 ₂ ) and hypochlorous acid (HClO) may include any one or more selected from the group consisting of. In this case, when the mixed desiccant is added to the organic waste, a neutralization reaction can be performed to efficiently obtain a basic intermediate product.

In this case, the pH of the intermediate product may be at least pH 11. In this case, the pH of the intermediate product can be adjusted to pH 11 or higher regardless of the acidity of the organic waste performing the initial reaction, so it is easy to obtain a final product maintaining pH 7 to 9 using the intermediate product. there is.

On the other hand, the lime stabilization reaction and the neutralization reaction by the above-mentioned mixed desiccant can be carried out simultaneously by picking, and these chemical reactions are carried out in a chain to remove moisture from the leachate generated during the organic waste treatment process and dry it to the environment. ingress can be prevented. At the same time, since the reaction of Scheme 1 is an exothermic reaction, there is an effect of sterilizing bacteria and the like by the generated heat (steam).

Accordingly, the present invention can provide a composition for treating leachate that prevents environmental pollution while leaving beneficial organic components and provides a sterilizing effect. In addition, as described below, beneficial organic ingredients can be recycled as raw materials for fertilizer or animal feed.

The content of the oxidizing agent in the mixed desiccant may be determined according to the acidity of the organic waste, and may be contained to an extent capable of producing a basic intermediate product through a neutralization reaction with the organic waste.

Preferably, the mixed desiccant may include 10 to 200 parts by weight of an oxidizing agent based on 100 parts by weight of quicklime. More preferably, the oxidizing agent may be included in an amount of 10 to 100 parts by weight based on 100 parts by weight of quicklime. When the oxidizing agent is included within the above range, when the mixed drying agent is added to the organic waste, a neutralization reaction occurs effectively to obtain a basic intermediate product.

In addition, according to a preferred embodiment of the present invention, the mixed desiccant may further include a coagulant.

The coagulant can be a wide range of compounds that can aggregate into large substances by combining suspended and dispersed fine particles or colloidal particles in water, but preferably aluminum sulfate (Al ₂ (SO _{4 ) 3} ·14H). ₂ O), iron sulfate (Fe ₂ (SO ₄ ) ₃ 7H ₂ O), ammonium aluminum sulfate (AlH ₄ NO ₈ S ₂ 12H ₂ O), iron chloride (FeCl ₃ ), potassium aluminum sulfate (AlKO ₈ S _{2 )} ·12H ₂ O), sodium aluminate (Na ₂ O·Al ₂ O ₃ ), sodium silicate (Na ₂ O·SiO ₂ ), and any one or more selected from the group consisting of bentonite may be used.

In this case, the coagulant can react with water contained in the organic waste and quicklime contained in the mixed desiccant with remarkably high reactivity, and has the effect of generating excessive heat of reaction. The reaction scheme performed when aluminum sulfate is used as the coagulant is shown in Scheme 2 below.

[Scheme 2]

3CaO + H ₂ O + Al ₂ (SO ₄ ) ₃ → 3CaSO ₄ ↓ + 2Al(OH) ₃ , ΔH < 0

Referring to Scheme 2, aluminum sulfate as a coagulant remarkably improves the reactivity between quicklime and water, thereby generating excess heat. That is, the mixed desiccant may cause chemical reactions to occur in a chain and amplification manner, and may induce drying through the formation of hydrates by using a hydration reaction and an acid-alkali reaction together. Accordingly, the moisture contained in the organic waste can be effectively removed and dried, and since excess heat is generated, the effect of sterilizing bacteria is remarkably excellent.

The content of the coagulant in the mixed desiccant may vary depending on the acidity of the organic waste, and may be contained to an extent capable of effectively drying and sterilizing the organic waste by performing an exothermic reaction with the organic waste.

Preferably, the mixed desiccant may include 10 to 400 parts by weight of a coagulant based on 100 parts by weight of quicklime. More preferably, it may be included in an amount of 20 to 100 parts by weight. When the coagulant is included within the above range, when the mixed desiccant is added to the organic waste, chemical reactions occur in a chain and amplified manner, thereby increasing the moisture removal effect and the sterilization effect by the heat of reaction.

When the intermediate product is produced by adding the mixed desiccant as described above, the moisture content of the intermediate product may have a lower value than that of the organic waste. For example, when the moisture content of the organic waste is 80 to 95%, the moisture content of the intermediate product may be 35 to 70%, more preferably 35 to 55%.

In addition, when an intermediate product is produced by adding a mixed desiccant as described above, the intermediate product may have strong alkalinity. For example, when the pH of the organic waste is 3.5 to 8.5, the pH of the heavy acid product may be at least pH 11.

Next, (2) _{adding carbon dioxide (CO 2} ) to the intermediate product through a neutralization reaction to obtain a final product of pH 7-9 (S2) will be described.

_{As described above, by adding carbon dioxide (CO 2} ) to the intermediate product obtained through step S1, a neutral or weakly basic organic material having a pH of 7 to 9 can be obtained as a final product. At this time, the organic material obtained as a final product is in a dry state by removing moisture, in a state in which bacteria and the like are removed by sterilization, and has neutral or weak basic properties, so that it can be used as a raw material such as fertilizer or feed. .

When carbon dioxide (CO ₂ ) is added to the intermediate product, a neutralization reaction according to Scheme 3 below occurs.

[Scheme 3]

Ca(OH) ₂ + CO ₂ → CaCO ₃ + H ₂ O, ΔH < 0

Calcium hydroxide (Ca(OH) ₂ ) of Scheme 3 is produced by the lime stabilization reaction of Scheme 1. The calcium hydroxide may perform a neutralization reaction capable of lowering the pH by reacting with _{carbon dioxide (CO 2 ) to obtain a final product of pH 7 to 9.} As described above, the present invention has the advantage of being able to obtain a neutral or weakly basic organic material as a final product by performing a chain and multi-step chemical reaction.

In addition, since the reaction of Scheme 3 is an exothermic reaction, the process of sterilizing bacteria by the generated heat (steam) is additionally performed, and there is no concern about toxicity, so it can be usefully used as an organic raw material such as feed or fertilizer. There are advantages that can be In addition, moisture can be additionally removed by the generated heat, so there is an advantage in that it is possible to efficiently obtain a dried final product.

As such, when carbon dioxide (CO ₂ ) is added to generate a final product from an intermediate product, the moisture content of the final product may have a lower value than that of organic waste and the intermediate product. For example, when the moisture content of the organic waste is 80 to 95%, the moisture content of the intermediate product may be 35 to 70%, and the moisture content of the final product may be 35 to 60%. More preferably, the moisture content of the intermediate product and the final product may be 35 to 55%.

In addition, as described above, when carbon dioxide (CO ₂ ) is added to produce a final product from an intermediate product, the final product may have neutral or slightly alkaline properties. For example, when the pH of the organic waste is 3.5 to 8.5, the pH of the heavy acid product may be at least pH 11, and the pH of the final product may be at pH 7 to 9.

In addition, according to a preferred embodiment of the present invention, the present invention may satisfy both of the following conditions (a) and (b).

(a)

(b)

(Wx: moisture content of organic waste, Wy: moisture content of intermediate product, Wz: moisture content of final product)

In this case, it is possible to effectively remove the moisture contained in the organic waste to obtain dried organic matter, which can be usefully used as a raw material for fertilizer or feed, and at the same time to prevent the leachate generated during the organic waste treatment process from entering the environment It also has the effect of preventing environmental pollution.

In addition, the present invention provides an organic material prepared by the method of any one of the above. Through this, it is possible to obtain organic matter from which moisture and toxicity (bacteria, etc.) are removed while still containing nutrients contained in various water-containing organic wastes such as livestock waste, food waste, and sewage sludge. Such organic matter can be used as a raw material for various substances including organic matter as a raw material, such as fertilizer or feed.

In particular, as described above, since the organic material of the present invention is neutral or weakly basic, it is not harmful to animals even when used as a raw material for animal feed, so it is possible to provide an organic material that can be used as a raw material for animal feed only by a simple chemical reaction. .

Furthermore, the present invention provides a feed or fertilizer comprising the above-mentioned organic matter as a raw material. In this case, there is an effect that it can be recycled as an organic material containing useful nutrients contained in the organic waste to be disposed of as it is by a simple process.

Hereinafter, the present invention will be described in more detail through specific examples.

Example One

A mixed desiccant containing 15 to 50% by weight of quicklime, 5 to 30% by weight of sodium percarbonate, and 10 to 60% by weight of aluminum sulfate was added to organic waste with a water content of 90% and pH 3.9 to 1 through a lime stabilization reaction and a neutralization reaction. A tea dried intermediate product was obtained. A neutralization reaction was performed by injecting carbon dioxide into the intermediate product to obtain a dried organic material as a final product.

Example 2

A mixed desiccant containing 30 to 50% by weight of quicklime, 5 to 10% by weight of sodium percarbonate, and 5 to 10% by weight of aluminum sulfate is added to organic waste with a water content of 95% and pH 7.53 to 1 through lime stabilization and neutralization. It was carried out in the same manner as in Example 1, except that a tea-dried intermediate product was obtained.

Experimental example 1. Moisture content measurement

The moisture content of each of the intermediate products and final products of Examples 1 and 2 was measured and shown in Table 1 below.

Experimental example 2. pH measurement

The pH of each of the intermediate products and final products of Examples 1 and 2 was measured and shown in Table 1 below.

Moisture content (%) pH Example 1 organic waste 90 3.9 intermediate 54 12.2 final product 38 8.4 Example 2 organic waste 95 7.53 intermediate 52 12.2 final product 43 8.5

Referring to Table 1, it can be seen that the moisture content of the intermediate product and the final product is significantly lower than that of the organic waste. Through this, it can be confirmed that the present invention can remove moisture from organic waste to produce dried organic matter.

In addition, referring to Table 1, it can be seen that the pH of the final product has a value between pH 7 and 9. Through this, it can be seen that the organic material, which is the final product produced through the organic waste recycling method of the present invention, is neutral or weakly basic, and thus can be directly utilized as an organic raw material for feed or fertilizer.

Claims (9)

(1) adding a mixed desiccant to organic waste to produce an intermediate product of pH 11 or higher through a lime stabilization reaction; and
(2) adding carbon dioxide (CO ₂ ) to the intermediate product to obtain a final product of pH 7 to 9 through a neutralization reaction; including,
The mixed drying agent contains 10 to 100 parts by weight of an oxidizing agent and 20 to 100 parts by weight of a coagulant based on 100 parts by weight of quicklime,
An organic waste recycling method that satisfies all of the following conditions (a) and (b).
(a)

(b)

(Wx: moisture content of organic waste, Wy: moisture content of the first intermediate product, Wz: moisture content of final product)
delete According to claim 1,
The oxidizing agent is sodium percarbonate (2Na ₂ CO ₃ ·3H ₂ O ₂ ), potassium permanganate (KMnO ₄ ), chlorine dioxide (ClO ₂ ), ozone (O ₃ ), hydrogen peroxide (H ₂ 0 ₂ ) and hypochlorous acid (HClO) Organic waste recycling method comprising any one or more selected from the group consisting of.
delete delete According to claim 1,
The coagulant is aluminum sulfate (Al2(SO4)3·14H2O), ferric sulfate (Fe ₂ (SO ₄ ) ₃ ·7H ₂ O), ammonium aluminum sulfate (AlH ₄ NO ₈ S ₂ ·12H ₂ O), ferric chloride ( FeCl ₃ ), potassium aluminum sulfate (AlKO ₈ S2·12H ₂ O), sodium aluminate (Na ₂ O·Al ₂ O ₃ ), sodium silicate (Na ₂ O·SiO ₂ ) and any one selected from the group consisting of bentonite Organic waste recycling method, characterized in that at least one.
delete An organic material prepared by the method of any one of claims 1, 3 and 6.
Feed containing the organic matter of claim 8 as a raw material.

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