KR101106129B1 - A desalter of organicity waste including salt - Google Patents

Abstract

The present invention relates to a device for desalting salt (NaCl) of organic waste containing salts such as food waste, livestock manure or food waste, and more specifically, salt such as food waste, livestock manure or food waste. The present invention relates to an apparatus for desalting a salt contained in an organic waste by electrophoresis in order to compost or feed the organic waste containing the same.

To this end, the present invention, the present invention is a diaphragm on both sides up to a concentration where there is no problem of salts caused by salt (NaCl) when composting or feeding organic waste containing salt such as food waste, livestock manure or food waste. Organic waste containing salt is injected into the desalination chamber (2) where the attached multi-screw mixer (3) is attached, and direct current is applied from the rectifier to the anode (6) and the cathode (7) installed outside the diaphragm. When salt is extracted from the organic waste of the desalting chamber 2 into the salt extraction chamber 1 while forming an electric field in the desalting chamber 2 and extracting and removing the salt by electrophoresis, the air from the blower 8 is removed. By aeration through the acid pipe (9) to suppress the side reactions and the generation of odor generating substances such as Cl ₂ and ClO ₂ to remove the salt from the organic waste containing salt.

At present, there have been attempts to separate and collect food wastes and to recycle them in various ways, such as composting, feed, and energyization. However, since food wastes have a high salt concentration, they cannot be processed smoothly. Likewise, it is expected to be widely used for the treatment of organic waste containing salt.

Desalination unit, organic waste, direct current, salt, diaphragm, anode, cathode, electric field, electrophoresis

Description

A desalter of organicity waste including salt}

1 is a front view of a desalination apparatus of a small amount organic waste

Figure 2 is a top view of the desalination apparatus of a small amount of organic waste

3 is a cross-sectional view of the desalination unit of the organic waste (small capacity and the same large capacity)

Figure 4 is a front view of the desalination device of a large amount of organic waste

Figure 5 is a top view of the desalination apparatus of a large amount of organic waste

<Explanation of symbols for main parts of drawing>

1: salt extraction chamber 2: desalination chamber

3: screw mixer 4: diaphragm

5: diaphragm supporter 6: anode

7: Cathode 8: Air blower

9: diffuser

The present invention is a multi-layered screw mixer with a diaphragm attached to both sides to a concentration where there is no salt problem caused by salt (NaCl) when composting or feeding organic waste containing salt such as food waste, livestock manure or food waste. Organic waste containing salt is injected into the desalination chamber where a screw mixer is installed, and direct current is applied from the rectifier to the anode and cathode installed outside the diaphragm to form an electric field in the desalination chamber. It relates to a desalination apparatus (脫鹽 裝置) for extracting and removing the salt into the extraction chamber.

Methane gas generated by composting, feed, and anaerobic fermentation is made by recycling organic wastes containing salt such as food waste, livestock manure or food waste. Because of high concentration of salt (NaCl), plant growth disorder due to osmotic phenomenon and Na are replaced with Ca and Mg in soil, and the grain structure of soil is destroyed, resulting in a monolithic structure. It is impossible to compost organic wastes containing salt such as food waste, livestock manure or food waste without removing salt because oxygen supply becomes difficult due to poor breathability and drainage, which impedes the growth of crops.

In addition, in the case of feeding organic wastes with high salt concentrations such as food waste into livestock, the salt concentration (2 to 6%) is much higher than the optimum level of salinity (0.3 to 1.0%) in feeds, ) As well as the phenomenon of thirst, water intake increases due to thirst, which reduces digestion and absorption efficiency, slows down the growth rate, increases urine excretion, and increases the amount of wastewater generated. It should be removed to 0.5wt% before use as feed.

In the case of methane gas energy by anaerobic fermentation, methane gas generation efficiency is lowered because it impedes the growth of anaerobic microorganisms with low flame resistance, so it must also remove salt concentration as much as possible.

As a desalination apparatus for food waste, Korean Patent Registration No. 10-0284282 removes the salts contained in food waste by a reaction mechanism by the following electrolysis.

Anode Reaction:

^{_{2Cl - → Cl 2 (aq)}} + 2e -, E = 1.3961Volt ... … … … … … … … … … … … … … … … (One)

Cathodic Reaction:

_{^{2Na + + 2H 2 O + 2e}} - → 2NaOH + H 2 (g) ↑ E = -0.8285Volt ... … … … … … … … … (2)

Overall reaction:

2NaCl + 2H ₂ O → Cl _{2 ( aq )} + 2NaOH + H _{2 (g)} ↑ E = 2.2246 Volt. … … … … … … (3)

Anode chamber solution reaction:

Cl _{2 ( aq )} + H ₂ O → HClO + HCl... … … … … … … … … … … … … … … … … … … … (4)

Negative reaction when overvoltage is applied:

_{HClO + H 2 O → HClO 2} + 2H + + 2e - ... … … … … … … … … … … … … … … … … (5)

_{HClO 2 + H 2 O → HClO} 3 + 2H + + 2e - ... … … … … … … … … … … … … … … … (6)

^{2HClO + 2H + + 2e - →} Cl 2 (g) ↑ + 2H 2 O … … … … … … … … … … … … … … … (7)

_{^{ClO 3 - + 2H + + e}} - → ClO 2 (g) ↑ + H 2 O … … … … … … … … … … … … … … … … (8)

When the salinity was removed from the food waste by the above-mentioned electrolysis reaction, the salinity removal rate was excellent, but there are the following problems.

First, when a direct current was applied while the anode chamber and the cathode chamber were separated into anion exchange membrane and cation exchange membrane, Cl ^- ions in the food waste pass through the anion exchange membrane and electrolytic oxidation water such as HClOx and Cl _{2 ( g)} is generated, and Na ⁺ ions in the food waste react with water (H ₂ O) as they pass through the cation exchange diaphragm to generate NaOH and hydrogen (H ₂ ).

In other words, NaCl contained in the food waste is separated into an anion exchange membrane and a cation exchange diaphragm into an anode chamber and a cathode chamber, so that NaCl is supplied to HClOx, HCl, Cl _{2 (g)} and NaOH, H ₂ O, etc. It decomposes when decomposed.

When removing 1 kg-mole of NaCl contained in food waste by electrolysis as above, the current required to apply 1 Faraday (26.8 kW-h / kg-eq) should be applied.

Specifically, the current required theoretically to remove 58.5 kg NaCl 1 kg gram water (kg-mole) by electrolysis reaction is to apply a current of 26,800 amperes, and the applied voltage is the theory of equation (3). Considering the decomposition voltage of 2.2246 Volt, positive overvoltage, negative overvoltage, ohmic resistance of the solution, and ohmic resistance of the conductor, a power consumption of 3 to 100 Volt should be applied. .

As described above, the desalination method by electrolysis has a disadvantage in that a large amount of power is consumed.

Second, in order to apply a high current, the facility cost is high because the area of the electrode plate, the area of the ion exchange membrane, the capacity of the rectifier and other devices are increased.

Third, in order to improve the desalination efficiency, when the applied voltage is increased, a negative reaction of reaction equation (5) to (8) occurs in the anode chamber, and gases such as Cl _{2 (g)} and ClO _{2 (g)} are generated. Odor may occur.

In the case of Korean Patent Registration No. 10-0445641, in case of "desalting method of waste liquid or organic waste" by electrodialysis, it is clogged when supplying it to the desalination chamber in case of high solid concentration such as food waste. ) There is a problem that can not be applied to the phenomenon.

As a patent for solving the problem in the method of desalting salts of organic wastes having high salt concentration such as food waste, in the case of Korea Patent Registration No. 10-0423568, a diaphragm is installed outside the porous screw conveyor. A method of extracting salt by forming an electric field inside the conveying screw conveyor by applying a direct current from the rectifier while supplying and transporting food waste to the screw conveyor by installing a circular electrode outside the diaphragm. Although the distance between the electrodes is not fixed by installing a circular anode and a cathode, a uniform current density is not applied in the electrode plate, and an excessive current density is formed at a short distance. Has caused problems with high odor and high power loss. .

NaCl + H ₂ O → NaClO + H _{2 (g)} ↑. … … … … … … … … … … … … … … … … … (9)

NaClO + 2H ₂ O → NaClO ₃ + 2H _{2 (g)} ↑. … … … … … … … … … … … … … … … … 10

NaClO ₃ + H ₂ O → NaClO ₄ + H _{2 (g)} ↑. … … … … … … … … … … … … … … … … (11)

^{_{2Cl - → Cl 2 (aq)}} + 2e - → Cl 2 (g) ↑ ... … … … … … … … … … … … … … … … … … (12)

In the case of Korean Patent Registration No. 10-0336868, organic waste is removed by applying direct current electricity to the electrolyte in organic waste resources by removing harmful ions such as heavy metals and salts contained in organic waste resources such as food waste and sewage sludge. Among the ions contained in the resource, there is a method of collecting and discharging ions collected in a solution state in the positive electrode of the electrode and positive ions in the negative electrode of the electrode. Since the treatment efficiency is reduced by treating, the concentration of organic pollutants in the demineralized water is high, so there is a problem of separately treating the organic material in the demineralized water (wastewater treatment).

In order to solve the above problems, the present invention injects organic waste containing salts such as food waste, livestock waste or food waste into a desalting chamber equipped with a screw mixer with a diaphragm attached to the outside, and an anode installed outside the diaphragm. It is an object of the present invention to provide a device for extracting and removing salt contained in food waste by applying a direct current electric current from the rectifier to the cathode to form an electric field inside the desalination chamber.

In order to achieve the above object, the present invention injects organic waste containing salt such as food waste, livestock waste or food waste into a desalting chamber equipped with a multilayer screw mixer with a diaphragm on both sides, and is installed outside the diaphragm. Injecting air from the blower while applying DC electricity from the rectifier to the anode and cathode to aeration to suppress the side reactions in the demineralized water as much as possible to reduce the power ratio while reducing the generation of odorous gases such as Cl ₂ , ClO _2, etc. It is characterized by desalination without causing pollution problems.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

To recycle organic wastes containing salts such as food waste, livestock manure or food waste into compost, feed, and energyification of methane gas produced by anaerobic fermentation, first, vinyl bags, stones, glass fragments, Foreign substances such as iron are separated by microorganisms that produce degrading enzymes such as amylase, lipase, protease, etc. ), A salt mixer (3) with a diaphragm (4) attached on both sides of the denitrification, which has been subjected to fermentation treatment and soft nitridation for good odor removal and fluidity. The electric field is applied to the desalination chamber 2 by supplying 3-50 volts of direct current electricity from the rectifier to the anode 6 and the cathode 7 while supplying the chamber 2. brother If cations such as Na ⁺ ions by electrophoresis (電氣泳動) are moved to the negative electrode 7 side of the diaphragm (4) salt extraction chamber (1) through a, Cl ^- anions, such as the ions are positive (6 After passing through the diaphragm 4 on the side) to the salt extraction chamber 1, the salt (NaCl) is desalted from the organic waste.

When the processing capacity of organic wastes containing salt such as food waste, livestock waste or food waste is large, as shown in FIGS. 4 and 5, a plurality of screw mixers 3 having a diaphragm 4 on both sides are installed in the vertical direction. The desalination chamber 2 is provided in the horizontal direction, and the desalination chamber 2 of the desalination apparatus 2 in which the anode 6 and the cathode 7 are alternately installed between the desalination chambers 2 is organic. When 3 to 50 volts of direct current is applied from the rectifier to the anode 6 and the cathode 7 while supplying the waste, an electric field is formed in the desalination chamber 2, whereby cations such as Na ⁺ ions Passes through the diaphragm 4 on the negative electrode 7 side and moves to the salt extraction chamber 1, and anions such as Cl ⁻ ions pass through the diaphragm 4 on the positive electrode 6 side and the salt extraction chamber 1. The salts contained in the organic waste are desalted as it moves to.

The desalination mechanism (Mechanism) in the organic waste having a high salt content of the present invention will be described in detail.

NaCl contained in salt-containing organic waste such as food waste, livestock waste or food waste is dissociated into Na ⁺ and Cl ^- ions by water and hydrolysis reaction as shown in the following reaction (13). )do.

^{_{NaCl --H 2 O- → Na + +}} Cl - ... … … … … … … … … … … … … … … (13)

When a direct current is applied from the rectifier to the anode 6 and the cathode 7 to form an electric field inside the desalination chamber 2, the Na ⁺ ions in the organic waste of the desalination chamber 2 are separated from the diaphragm 4 at the cathode 7 side. ) To move to the salt extraction chamber (1), Cl ^- ions are passed to the salt extraction chamber (1) through the diaphragm (4) toward the anode (6) organic waste of the desalting chamber (2) NaCl is removed (desalted) from the.

Na ⁺ --septum-> Na ⁺ ... … … … … … … … … … … … … … … … (14)

Cl ^{- -} Diaphragm ^- → Cl - ... … … … … … … … … … … … … … … … (15)

Na ⁺ ions and Cl ⁻ ions transferred to the salt extraction chamber 1 are in situ in the original NaCl state.

Na ⁺ + Cl ⁻ -—H ₂ O— → NaCl... … … … … … … … … … … … … … (16)

On the anode 6 and cathode 7 sides, there is a possibility that odor generation and power consumption may increase when the following side reactions occur, such that air from the air blower (8) is diffused into the air. Through aiffuser (9), aeration is carried out so that side reactions are suppressed as much as possible.

2Cl ⁻ → Cl _{2 ( aq )} + 2e ⁻ . … … … … … … … … … … … … … … … … … … (17)

Cl _{2 ( aq )} → Cl _{2 (g)} ↑. … … … … … … … … … … … … … … … … … … … (18)

Cl _{2 ( aq )} + H ₂ O → HClO _{( aq )} + HCl... … … … … … … … … … … … … … … (19)

^{_{2HClO (aq) + 2H + +}} 2e - → Cl 2 (g) ↑ + 2H 2 O ... … … … … … … … … … 20

^{_{2H 2 O + 2e - → 2OH}} - + H 2 (g) ↑ ... … … … … … … … … … … … … … … … (21)

At this time, the supply amount of air supplied from the blower 8 through the diffuser 9 is such that the intensity of aeration is 1.2 to 2.0 air (m 3) / trough capacity (m 3).

According to a particular aspect of the present invention, compared to the desalination method by electrolysis or electrodialysis, the desalination does not occur at all by the decomposition reaction of NaCl, and the salt contained in the organic waste of the desalting chamber 2 ( NaCl) is applied from the rectifier to the anode (6) and the cathode (7) by direct current, so that Na ⁺ ions pass through the diaphragm (4) toward the anode (6) to the salt extraction chamber (1), Cl ⁻ The ions move through the diaphragm 4 on the anode 6 side to the salt extraction chamber 1, whereby NaCl is extracted and removed as an in situ reaction takes place in the original NaCl state. Less power consumption because no current consumption by.

And since the distance between the positive electrode 6 and the negative electrode 7 is constant, and no specific portion is present in close proximity, there is little possibility that side reactions such as (21) in the above-described reaction formula (17) occur, and uniform in the electrode plate. Since the current density can be maintained, the desalination efficiency is high.

Salt extraction chamber (1), desalination chamber (2) and screw mixer (3) are made of SUS-316L, titanium, or carbon coating or lining of carbon steel. Lining) or lining the fiber glass reinforced plastic (FRP).

The material of the negative electrode plate 6 is a steel plate of high hydrogen generation overvoltage, which is lined with Rainy nickel, SUS-316L, or titanium plate. The positive electrode plate 6 is a die-coated die coated with TiO ₂ -RuO ₂ on a titanium plate made of a material having excellent corrosion resistance and high oxygen and chlorine generation overvoltage. DSA: Dimensionally Stable Anode) electrode.

The diaphragm 4 uses an anion exchange diaphragm that selectively exchanges only anions as the diaphragm 4 on the positive electrode 6 side, as in the electrode dialysis apparatus, and the positive electrode selectively selects cations on the negative electrode 7 side. An anion exchange diaphragm may be used, but in the present invention, asbestos (nylon, polyamide), polyolefin, polyfluoroolefin, polyester, and polyethylene , A copolymer of polypropylene, tetrafluoroethylene, polytetrafluoroethylene, polyvinylidene fluoride and hexafluoropropylene. 0.5 to 1.0 mm thick membranes may be used.

The diaphragm supporter 5 is a porous plate or grid plate of SUS-316L or titanium on a nonwoven fabric made of synthetic resin such as viscose rayon or nylon having a thickness of 1 to 10 mm outside the diaphragm 4. Fix it with 格子 板).

Example 1

1 to 3, the desalination apparatus has a capacity of 1 m 3 (250 mm × 1,000 m 3 × 4,000 mm), a salt extraction chamber of 3.24 m 3 (750 mm 1,200 mm 3,600 mm), and an anode. Three sheets of DSA electrode coated with TiO ₂ -RuO ₂ coated on a 1,000mm × 1,200mm titanium plate and three sheets of 1,000mm × 1,200mm titanium plate electrode.The material and size of the diaphragm on the anode side and the diaphragm on the cathode side. Ton of food waste with a salt content of 2.32wt% in a desalting unit equipped with four screw mixers 200mmφ3,600mm in a one-stage desalting chamber using 3,600mm × 1,000mm diaphragm with the same polyester 3mm thickness. The results of measuring the current and the salt removal rate by applying a DC voltage of 3 to 10 Volts from the rectifier while supplying hr were as shown in Table 1 below.

Table 1 Food waste desalination test report

  Voltage applied (Volt)     3    5     6     10  Ampere    60   82   102    142 Salinity (wt%) in treated food waste    1.62   0.83    0.28     0.07   Desalination Rate (%)    30.2   64.2    87.9     97.0

(Note: The theoretical applied current is 8246A for desalination by electrolysis of 1Ton / hr of food waste with salt content of 2.3wt% to 0.5wt%.)

As described above, according to the present invention, organic waste containing salt such as food waste, livestock manure or food waste is composted, feed, methane gas (CH ₄ ) energy by methane fermentation, etc. It is expected that the organic waste, which is difficult due to its high concentration, can be desalted to a salt concentration below the salt level, so that the organic waste treatment process can be widely used.

Claims (2)

Desalination chamber (2) equipped with a screw mixer (3) with a diaphragm attached to both sides of organic wastes containing salts such as food waste, livestock manure or food waste (4). 3-50 volts of direct current from the rectifier is applied to the positive electrode 6 and the negative electrode 7, and an electric field is formed in the desalination chamber 2 by electrophoresis. Na ⁺ ions pass through the diaphragm 4 on the cathode 7 side to the salt extraction chamber 1, and Cl ⁻ ions pass through the diaphragm 4 on the anode 6 side and the salt extraction chamber 1 Desalting apparatus for desalting the salt (NaCl) contained in the organic waste by moving to). The desalination chamber according to claim 1, wherein in the case where the processing capacity of organic waste containing salt such as food waste, livestock waste or food waste is large, a screw mixer 3 having a diaphragm 4 attached to both surfaces thereof is provided in a vertical direction. The organic waste is desalted in the desalination chamber (2) in which a plurality of (2) are provided in the horizontal direction, and an anode (6) and a cathode (7) are alternately provided between the desalination chambers (2). While supplying to the rectifier, 3-50 volts of direct current is applied to the anode 6 and the cathode 7 to form an electric field in the desalination chamber 2, whereby Na ⁺ ions are released by the electrophoresis. It moves to the salt extraction chamber 1 through the diaphragm 4 of the side, and Cl <^-> ion moves to the salt extraction chamber 1 through the diaphragm 4 of the anode 6 side, and to an organic waste. Desalting apparatus for desalting the contained salt (NaCl).

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