KR100416653B1 - Sludge loosing method using Electo-chemical oxidation and reduction process for the polluted water treatment system - Google Patents

Abstract

The present invention relates to a wastewater treatment process by an electrochemical catalytic redox reaction and a device suitable therefor.

Sludge is generated when organic matter is decomposed and removed by waste sludge composed of various industrial water or domestic sewage. The sludge generated is disposed of through the weight loss process and used as incineration, ocean dumping, etc., which is another secondary source of pollution.

The present invention is to control the decomposition of most organic matter by the dual operation to increase the metabolism efficiency by abnormally increasing the energy metabolism of the microorganism and the contact redox treatment of inert organic matter by controlling the electrode contact to promote the organic decomposition metabolism of the microorganism as much as possible. To lower the production rate of sludge. In other words, microorganisms consume energy while oxidizing through multi-step metabolic pathways. When metabolic pathways are altered or blocked, they cannot maintain their functions, allowing microorganisms to produce more energy. It is to increase the decomposition efficiency.

In addition, these devices can be easily installed and used in existing facilities, and the existing facilities can be used as they are without the need for process changes or individual objects of the facilities. will be.

Description

Sludge loosing method using Electo-chemical oxidation and reduction process for the polluted water treatment system

The present invention relates to a sludge reduction method in a wastewater treatment process by an electrochemical catalytic redox reaction.

Sewage is a wastewater used and used in human activities. Most of the sewage is sewage. However, in the process of treating sewage, 30-40% of organic matter is converted into biomass and mixed with hardly decomposable organic suspended matter and inorganic matter to form sludge, which is further disposed of through sludge treatment.

In general, about 60% of the sludge is water and 40% of the solid is inorganic, so in theory, about 36% of the sludge is organic. Since sludge is generally treated by fermentation process through anaerobic digester, only 60% of organic matter is decomposed and the rest is retained as biomass. About 38-40% of the sludge is treated through landfill, ocean dumping, incineration, etc. Finally processed.

This sludge treatment process has a longer residence time than the treatment process of wastewater, which inevitably leads to an increase in capacity, and may cause secondary air pollution due to warming gas and odor generated during the treatment process. Therefore, the original sludge reduction technology can partially solve the problems caused by sludge treatment cost, treatment time, secondary pollution, landfilling, incineration, ocean dumping, etc. have.

Most of the wastewater is generated in the process of using industrial water, and it is impossible to treat it in a uniform way because the difference in the content and composition of the wastewater is large depending on the target process. However, since the wastewater is not toxic or hardly decomposable, such as sewage, sludge generation may be proportional to the concentration of organic matter in the wastewater, such as sewage. However, sludge from wastewater, unlike sewage, may contain process-specific hardly decomposable and potentially toxic substances, so once sludge is generated, special management may be required for incineration or landfill. Therefore, minimizing sludge generation as much as possible is advantageous for environmental conservation and development of economical treatment process.

Since wastewater treatment plants related to wastewater in various industrial sites in Korea discharge various kinds of hardly decomposable substances, chemical flocculation treatment is required, and the amount of chemical sludge generated must be treated through secondary and tertiary treatment processes. The treatment of waste water may require more time and cost for the treatment of sludge from the treatment of raw waste water than the treatment of raw waste water.

In order to biologically treat industrial wastewater, the activated sludge method of adsorbing and decomposing organic substances by activated aerobic microorganisms is most used, but there are disadvantages in that a large amount of sludge is generated and solid-liquid separation in a sedimentation tank is difficult. In addition, various hardly decomposable substances in the waste water can affect the activity of most microorganisms and thus affect the treatment efficiency.

The most common wastewater treatment technology to remove organic matter from wastewater is the integrated treatment of wastewater generated in the plant in a batch process. However, this method is a method of treating domestic wastewater or household sewage, which has many problems in high concentration and hardly degradable factory wastewater treatment, and is recognized as an inefficient treatment method. The most preferable method is to classify and treat the wastewater generated in each process, which requires a lot of additional equipment investment and requires a high treatment cost because it requires linking process by process. This batch integrated treatment method is difficult to apply practically because it is possible to completely discharge the detergent, heavy metals, lubricants, organic solvents, inorganic acids, etc. by each process.

The present invention promotes microbial metabolic activity by irregularly changing the growth environment of microorganisms in a biological treatment process and ultimately promotes free energy consumption produced in the metabolic process of microorganisms by artificially providing an opportunity for microbial oxidation-reduction metabolism. It is.

In addition, in order to promote the consumption of free energy, it is possible to promote the desired metabolic activity only by the installation of the electrode and the low power supply of less than 4V to the electrode without the need for expensive facilities or additional facilities.

In addition, since it is divided into yin and yang electrodes and is supplied to the respiratory environment, since the hardly decomposable organic matter may be oxidized or reduced on the electrode surface, it is converted into a structure decomposable by microorganisms, thereby enabling efficient decomposition and removal.

In particular, the stress exerted by the conversion of the negative electrode promotes the overconsumption of the metabolic energy of the microorganism. If microorganisms have an excessive amount of organic matter in the microbial environment, organic matters can be decomposed to replenish energy required for overconsumption and form conditions to maintain biomass, thereby greatly increasing the efficiency of decomposition and removal of organic matter.

1 is a perspective view showing a representative installation state.

<Explanation of symbols for the main parts of the drawings>

DESCRIPTION OF SYMBOLS 1 Aeration tank 2 Porous membrane 3, 4 Electrode carrier 15 Sedimentation tank

The present invention is to install an electrode carrier capable of electrochemical catalytic redox reaction of a certain size per 10 tons in the reaction tank, through the voltage-current supply device that can change the negative-electrode irregularly after the same size of the negative electrode It is to provide a way to drastically reduce the amount of sludge generated without changing the structure of the existing process.

The voltage supplied in the present invention is a low voltage of 4V or less to allow the microorganism to adsorb to the oxidation or reduction electrode according to the physiological conditions of the microorganism. That is, microorganisms that produce energy by respiration are affected by the oxidation-reduction potential of the culture medium, so that bacteria requiring a reducing environment are absorbed at the cathode, and bacteria that require an oxidative environment are absorbed at the anode to maintain favorable physiological metabolism. Aerobic respiratory bacteria promote metabolic activity in an oxidative environment and anaerobic respiratory bacteria promote metabolic activity in a reducing environment. By maintaining the oxidation-reduction potential constant in this way, the metabolic activity of the microorganism as well as the hardly decomposable organic matter on the electrode surface can be oxidized or reduced to be converted into a structure decomposable by the microorganism, and stabilized by the oxidation-reduction reaction. The organic matter is to reduce the inhibitory action on the microorganism is to increase the efficiency.

The specific example of this invention is demonstrated by attached drawing.

1 is a perspective view showing a specific installation state of the present invention.

The present invention, in the aeration tank used in the activated sludge method for treating sewage and wastewater generated at home and industrial sites, by dividing the aeration tank by the porous diaphragm (2), at least one electrode carrier (3, 4) on each side ), And 50 ~ 60mA, 0.5 ~ 4V DC terminals are connected to the electrode carrier, and one side separated by the porous diaphragm is configured to be maintained as an oxidizing system and the other side as a reducing system. The metabolic activity of microorganisms is promoted by changing the supplied cathode and anode of the direct current or changing the amount of current irregularly to reduce the generation of sludge in the treatment of wastewater. The voltage supplied in the present invention is 0.5V or less. Is too weak to maintain the desired redox system, and if it is added above 4V, salts inside will electrochemically decompose, resulting in deactivation of microorganisms caused by by-products such as chlorine gas. Can be.

In the present invention, the porous membrane 2 has a thickness of 5 to 10 mm, and the reactive organic material is freely movable through the porous portion 2a formed in the membrane. Dividing into two layers of positive and negative by a porous diaphragm is extremely effective because the reaction occurs in the whole area separated by the diaphragm.

In the present invention, the electrode carrier (3) (4) is composed of an electrical conductor connecting different (+) (-) electrodes, specifically, a general metal, such as copper, iron is suitable, but the waste water supplied to the inside It is preferable to use a ceramic electrode body or a carbon electrode body as a conductor of an inorganic material having chemical resistance in view of the variety of properties.

In FIG. 1 provided as a device suitable for the present invention, three electrode-type carriers 3 and 4 are inserted into the aeration tank, but the installation numbers thereof can be increased or decreased by capacity, and the size is also increased or decreased according to the size and capacity of the installation tank. Give it. In addition, it is efficient to install the diffuser 20 in both the oxidizing system and the reducing system. In the present invention, only one side is provided for explanation, but the present invention is not intended to be limited thereto.

In the present invention, reference numeral 10 is an inlet water pipe, 11 is a reflux inlet pipe, 15 is a settling tank, 20 is an acid pipe.

As an example in which the apparatus of the present invention is actually installed, test results using dye wastewater provided by Jungnang Sewage Terminal Treatment Plant and Sinye Dye Plant in Uijeongbu City are presented.

Table 1 (Results of the treatment tank of Jungnang Sewage Sewage Treatment Plant)

division Analysis item Duration of experiment (days); Unit mg / l; sludge amount-dry weight One 2 3 4 5 6 enemy COD 114 115 118 111 111 123 NO₃ 2.44 2.43 2.2 2.1 2.3 2.2 NO₂ 0.33 0.12 0.22 0.22 0.12 0.21 PO₄ 0.34 0.34 0.38 0.34 0.42 0.89 TN 11.3 12.3 12.3 10.9 14.5 15.9 TP 1.23 1.34 1.23 1.54 2.03 1.98 Sludge Experiment COD 17.6 12.4 21.4 19.7 25.5 28.7 NO₃ 2.21 1.94 1.89 2.00 1.99 1.78 NO₂ 0.33 0.21 0.12 0.12 0.22 0.24 PO₄ 0.58 1.23 1.36 0.98 1.46 1.88 TN 12.4 9.8 9.6 8.4 9.3 11.5 TP 1.33 1.11 1.02 1.14 1.23 1.23 Sludge 12.7 11.5 10.8 13.1 12.5 11.4 Control COD 22.9 25.7 28.5 23.4 23.2 25.8 NO₃ 2.32 2.12 1.98 1.95 1.93 1.98 NO₂ 0.34 0.35 0.36 0.29 0.34 0.36 PO₄ 0.66 0.59 1.23 1.54 2.01 1.98 TN 13.3 12.1 12.5 11.5 10.6 10.3 TP 1.32 1.67 1.89 1.56 1.32 1.78 Sludge 24.5 24.6 26.3 28.2 24.6 22.5

Table 1 shows the quantitative change of COD, nitrate, nitrite, phosphate, total phosphorus, total nitrogen, etc. during the sewage treatment used in the sewage collection tank of Jungnang Sewage Terminal Treatment Plant. The amount of sludge released was reduced by more than 50%. Table 2 (Results of Treatment of Sewage in Jungnang Sewage Treatment Plant)

division Analysis item Duration of experiment (days); Unit mg / l; sludge amount-dry weight One 2 3 4 5 6 enemy COD 123 123 115 135 134 134 NO₃ 2.65 3.11 3.23 3.23 3.4 3.9 NO₂ 0.43 0.34 0.33 0.23 0.33 0.34 PO₄ 0.54 0.52 0.48 0.45 0.37 0.59 TN 11.4 14.3 13.6 13.7 13.9 13.2 TP 1.43 1.784 2.11 2.12 2.11 1.99 Sludge Experiment COD 21.3 14.5 15.4 16.2 22.4 24.5 NO₃ 1.67 1.56 1.66 1.55 1.74 1.65 NO₂ 0.43 0.42 0.39 0.23 0.21 0.25 PO₄ 0.45 0.34 0.34 0.32 0.43 0.44 TN 12.4 9.8 9.6 8.4 9.3 11.5 TP 1.21 1.22 0.99 0.89 1.34 1.12 Sludge 11.9 13.2 15.4 16.1 13.6 13.4 Control COD 24.3 22.5 21.5 19.8 19.8 25.9 NO₃ 1.77 1.78 1.93 1.78 1.99 1.93 NO₂ 0.43 0.42 0.21 0.35 0.37 0.39 PO₄ 0.55 0.65 0.65 0.68 0.54 0.45 TN 12.6 13.1 13.6 12.6 13.8 14.3 TP 1.43 1.56 1.98 2.09 2.14 1.98 Sludge 26.8 23.1 24.3 24.5 23.1 26.3

Table 2 shows the results of the treatment of sewage used in the sewage collection tank of Jungnang Sewage Terminal Treatment Plant after 2 weeks of experiment of Table 1, and the treatment efficiency of COD, nitrate, nitrite, phosphate, total phosphorus, total nitrogen, etc. Was increased by 20% and sludge production decreased by more than 60%. Table 3 (Results of Treatment of Dye Wastewater)

division Analysis item Duration of experiment (days); Unit mg / l; sludge amount-dry weight One 2 3 4 5 6 enemy COD 1736 1832 1960 1934 1816 1894 NO₃ 7.6 8.3 8.2 7.8 8.2 8.6 NO₂ 0.28 0.32 0.34 0.36 0.29 0.27 PO₄ 27.9 28.3 23.6 24.4 30.4 25.6 TN 33.5 38.4 41.4 34.9 37.6 36.5 TP 98.6 89.8 91.5 95.2 95.6 96.1 Sludge Experiment COD 383 415 395 413 405 393 NO₃ 5.7 4.8 6.3 4.7 5.5 6.4 NO₂ 0.03 0.35 0.04 0.06 0.04 0.08 PO₄ 24.3 23.6 18.8 19.6 21.6 18.2 TN 28.6 26.5 30.2 22.3 28.6 31.2 TP 78.5 80.0 69.4 67.3 77.0 72.4 Sludge 26.5 27.4 29.4 31.2 23.2 28.8 Control COD 504 543 512 498 487 535 NO₃ 6.4 7.3 8.4 8.8 7.3 6.9 NO₂ 0.2 0.1 0.23 0.2 0.1 0.2 PO₄ 22.9 28.5 25.4 22.1 24.3 25.9 TB 30.6 27.4 29.6 24.5 34.5 38.8 TP 83.2 79.9 78.2 80.0 83.2 84.3 Sludge 63.6 59.8 61.8 67.6 59.8 60.4

Table 3 above shows that the treatment efficiency of COD, nitrate, nitrite, phosphate, total phosphorus, total nitrogen, etc. was increased from about 10 to 15% as a result of the wastewater transported from the collection tank of Sambu Dyeing Wastewater Treatment Plant in Yongin. The amount of sludge produced was reduced by more than 40%.

As shown in the embodiment of the present invention, in the treatment of the waste water, the generation amount of sludge is drastically reduced even without physical and chemical pretreatment, thereby reducing the problems caused by the landfill or incineration of the sludge.

In particular, since the present invention achieves such an effect only by installing the porous diaphragm and the electrode-type carrier in the existing aeration tank, there is an advantage in that there is almost no cost incurred due to the design and structural change during the installation. It can be introduced and applied.

Claims (5)

delete delete In the aeration tank used in activated sludge method for treating sewage and wastewater generated at home and industrial sites, the aeration tank is divided into a porous diaphragm 2, and one or more electrode carriers 3 and 4 are provided on each side. One) Supplying a DC power supply of 50 ~ 60mA, 0.5 ~ 4V to the electrode carrier (3, 4) installed in the aeration tank (1) of claim 3 so that one side separated by the porous diaphragm (2) is maintained in the oxidizing system, the other side in the reducing system The method of treating sewage and wastewater by promoting the metabolic activity of microorganisms by changing the cathode and anode or changing the amount of current irregularly. The method according to claim 4, wherein the reaction organic matter is freely moved through the porous portion 2a formed in the porous diaphragm 2.