Desulfurization process water treatment system

Abstract

The present invention relates to a desulfurization process water treatment system capable of effectively removing and recirculating high-concentration ionic substances and organic substances contained in desulfurization process water, and a desulfurization process water treatment method thereof. The desulfurization process water treatment system comprises: a desulfurization treatment unit for desulfurizing exhaust gas introduced from the outside; and an electrochemical integrated desalination treatment unit for desalinating desulfurization process water introduced from the desulfurization treatment unit. The electrochemical integrated desalination treatment unit may include: an inflow source water tank for storing desulfurization process water introduced from the desulfurization treatment unit; a pretreatment unit for pretreating desulfurization process water by desalinating ionic substances and poorly soluble substances contained in desulfurization process water by using an electrochemical method integrating an oxidation and reduction reaction treatment and a reverse electrodialysis treatment; and a treatment water tank for storing desalinated treated water and recirculating the stored treated water to the desulfurization treatment unit.

Description

Desulfurization process water treatment system and method

[0001] The present invention relates to a desulfurization process water treatment system capable of effectively removing high-concentration ionic substances and organic substances contained in the desulfurization process water and recirculating them, and a desulfurization process water treatment method thereof.

[0002] Generally, thermal power plants using fossil fuels are equipped with wet desulfurization devices to remove sulfur oxides among the environmental pollutants contained in exhaust gases.

[0003] The wet desulfurization unit periodically performs limestone slurry circulation and bleeding to reduce sulfur oxides (SO2) and comply with environmental regulations.

[0004] In addition, the wet desulfurization device manages process water through slurry centrifugation, filtration dewatering, and dewatering filtrate recirculation.

[0005] However, conventional wet desulfurization devices recirculate the dehydrated liquid without separate pretreatment, which makes it difficult to manage ionic substances that are impurities.

[0006] In conventional wet desulfurization systems, if the dehydrated filtrate is recirculated without separate pretreatment, high concentrations of ionic substances (e.g., Cl-, F-, SO4) 2- (etc.), non-biodegradable organic nitrogen and organic matter, fine particles (colloids), etc., can continuously accumulate and deteriorate water quality inside the absorption tower, and SO4 2- , Ca 2+ Reactions involving , and other ions can cause hard scale to form on the inner walls of the equipment, which may lead to reduced heat transfer, blockage of flow paths, and equipment overload, and Cl - , F - Halogen ions accelerate the corrosion of metal surfaces, leading to problems such as reduced device durability and increased maintenance costs. Additionally, the deterioration of circulating water quality can impair the operating efficiency of the absorption tower and shorten maintenance and cleaning cycles.

[0007] In addition, existing wet desulfurization devices also had the problem of excessive operating costs due to increased wastewater treatment volume and increased chemical usage resulting from increased limestone slurry discharge.

[0008] Therefore, there is a need to develop a desulfurization process water treatment system that can effectively remove high concentrations of ionic substances and organic substances contained in the desulfurization process water and then recirculate it to inhibit equipment corrosion, extend equipment lifespan, prevent water pollution, and reduce treatment costs.

[0009] (Patent Document 1) Korean Registered Patent 10-0906805 (July 1, 2009)

[0010] One objective of the present invention, aimed at solving the aforementioned problems, is to provide a desulfurization process water treatment system and method capable of suppressing equipment corrosion, extending equipment lifespan, preventing water pollution, and reducing treatment costs by desalinating and recirculating the desulfurization process water using an electrochemical method that combines an oxidation and reduction reaction treatment method with a reverse electrodialysis treatment method.

[0011] The problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by a person skilled in the art from the description below.

[0012] A desulfurization process water treatment system according to one embodiment of the present invention for solving the above-mentioned problem comprises a desulfurization treatment unit that desulfurizes exhaust gas introduced from the outside, and an electrochemical fusion desalination treatment unit that desalinates the desulfurization process water introduced from the desulfurization treatment unit. The electrochemical fusion desalination treatment unit may include an inlet raw water tank that stores the desulfurization process water introduced from the desulfurization treatment unit, a pretreatment unit that pretreats the desulfurization process water by desalinating ionic substances and sparingly soluble substances contained in the desulfurization process water using an electrochemical method that combines an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method, and a treatment tank that stores the desalinated treated water and recirculates the stored treated water to the desulfurization treatment unit.

[0013] In an embodiment, the pretreatment unit may include an oxidation and reduction reaction treatment unit that pretreats the desulfurization process water by removing and decomposing insoluble substances contained in the desulfurization process water using an oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent, and discharges the pretreated water to a treatment tank; and a reverse electrodialysis unit that pretreats the desulfurization process water by separating and removing ionic substances contained in the desulfurization process water into cations and anions using a reverse electrodialysis treatment method, and discharges the pretreated water to a treatment tank.

[0014] In the embodiment, the pretreatment unit, when desalinating ionic substances contained in the desulfurization process water, applies an active radical reaction technology based on active oxygen species through the oxidation and reduction reaction treatment unit to the high concentration of chloride ions (Cl) contained in the desulfurization process water. - ) is removed by converting it into the intermediate chlorine (Cl2), and the remaining chloride ions (Cl2) are removed through a reverse electrodialysis unit. - ) is selectively separated and removed, and chloride ions are removed through an oxidation and reduction reaction treatment unit and a reverse electrodialysis unit, allowing the treated water with reduced high concentration of chloride ions to be discharged into a treatment tank.

[0015] In the embodiment, the pretreatment unit, when desalting sparingly soluble substances contained in the desulfurization process water, utilizes an active oxygen species-based activation reaction through the oxidation and reduction reaction treatment unit to remove NH3 and NO contained in the desulfurization process water. x Oxidative and reduction conversion of (NO, NO2) is performed, and the NH4 generated from the oxidation and reduction conversion is passed through a reverse electrodialysis unit. + , NO3 - , NO2 - Ions are selectively separated and removed, and the treated water from which total nitrogen (TN) has been removed through the oxidation and reduction reaction treatment unit and the reverse electrodialysis unit can be discharged into the treatment tank.

[0016] In an embodiment, the pretreatment unit may include a solid sedimentation unit that removes solids from desulfurization process water flowing in from an influent raw water tank by a sedimentation method and discharges the first pretreated treated water to a treatment tank; an oxidation and reduction reaction treatment unit that, when the first pretreated treated water stored in a treatment tank flows in, removes and decomposes insoluble substances contained in the first pretreated treated water by an oxidation and reduction reaction treatment method using an oxidizing agent and a reducing agent to perform second pretreatment and discharges the second pretreated treated water to a treatment tank; and a reverse electrodialysis unit that, when the first pretreated treated water stored in a treatment tank flows in, separates and removes ionic substances contained in the first pretreated treated water into cations and anions by a reverse electrodialysis treatment method to perform second pretreatment and discharges the second pretreated treated water to a treatment tank.

[0017] In an embodiment, the treatment tank may include a first treatment tank for storing desalinated treated water, and a second treatment tank for recirculating the treated water to a desulfurization treatment unit when the treated water stored from the first treatment tank flows in.

[0018] In an embodiment, the electrochemical fusion desalination treatment unit may further include a post-treatment unit that post-treats the treated water stored in a treatment tank using at least one of a reverse electrodialysis treatment method and a capacitive desalination treatment method, and discharges the post-treated treated water to the treatment tank.

[0019] In an embodiment, the electrochemical fusion desalination treatment unit may further include a discharge tank that stores wastewater discharged from an influent raw water tank and a pretreatment unit, and discharges the stored wastewater to a wastewater treatment plant.

[0020] A method for treating desulfurization process water of a desulfurization process water treatment system according to one embodiment of the present invention may include the steps of: treating exhaust gas introduced from the outside for desulfurization; collecting and storing desulfurization process water generated through desulfurization treatment; pretreating the desulfurization process water by desalinating ionic substances and sparingly soluble substances contained in the desulfurization process water using an electrochemical method that combines an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method; storing the pretreated water; and recirculating the stored treated water.

[0021] In an embodiment, the desulfurization process water treatment method may further include a step of post-treating the stored treated water using at least one of a reverse electrodialysis treatment method and a capacitive desalination treatment method.

[0022] In addition to this, other methods for implementing the present invention, other systems, and computer-readable recording media for recording a computer program for executing said method may be further provided.

[0023] As described above, according to the present invention, by desalinating and recirculating desulfurization process water using an electrochemical method that combines an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method, it is possible to inhibit equipment corrosion, extend equipment lifespan, prevent water pollution, and reduce treatment costs.

[0024] In addition, as an economic benefit, the present invention can reduce operating costs and industrial water usage for desulfurization wastewater treatment facilities, reduce maintenance costs for desulfurization facilities due to corrosion, ensure the quality of desulfurization gypsum, and stably generate revenue from by-products.

[0025] In addition, as a technical effect, the present invention enables safe operation of power generation facilities and desulfurization facilities, reduces industrial water usage through stable management of absorption tower slurry, and can be applied to solve maintenance and operation problems of desulfurization treatment water recycling facilities.

[0026] In addition, as a managerial effect, the present invention can comply with the government's resource circulation policy by reducing industrial water usage, enhance the image of an eco-friendly company through certification of new environmental technology, and fulfill a mutually beneficial social role by developing environmental conservation projects with small and medium-sized enterprises.

[0027] The effects of the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by a person skilled in the art from the description below.

[0028] FIG. 1 is a diagram illustrating the overall operation of a desulfurization process water treatment system according to one embodiment of the present invention.

[0029] FIG. 2 is a diagram illustrating the operation of a desulfurization treatment unit of a desulfurization process water treatment system according to one embodiment of the present invention.

[0030] FIGS. 3 and 4 are drawings for explaining the operation of a pretreatment unit of a desulfurization process water treatment system according to one embodiment of the present invention.

[0031] FIG. 5 is a diagram illustrating the overall operation of a desulfurization process water treatment system according to another embodiment of the present invention.

[0032] Figure 6 is a diagram illustrating the desulfurization process water treatment process of the desulfurization process water treatment system of Figure 1.

[0033] Figure 7 is a diagram illustrating the desulfurization process water treatment process of the desulfurization process water treatment system of Figure 5.

[0034] FIGS. 8 and 9 are drawings for illustrating treatment result data of a desulfurization process water treatment system according to one embodiment of the present invention.

[0035] FIG. 10 is a flowchart illustrating a method for treating desulfurization process water of a desulfurization process water treatment system according to one embodiment of the present invention.

[0036]

[0037] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the present invention, and the present invention is defined only by the scope of the claims.

[0038] The terms used in this specification are for describing embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text. The terms "comprises" and / or "comprising" used in this specification do not exclude the presence or addition of one or more other components in addition to the components mentioned. Throughout the specification, the same reference numerals refer to the same components, and "and / or" includes each of the mentioned components and all combinations of one or more. Although terms such as "first," "second," etc., are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another. Therefore, the first component mentioned below may be the second component within the technical scope of the invention.

[0039] Unless otherwise defined, all terms used herein (including technical and scientific terms) may be used in a meaning commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise.

[0040] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

[0041] Prior to the explanation, the meanings of the terms used in this specification are briefly explained. However, since the explanation of terms is intended to aid in understanding this specification, it should be noted that they are not used to limit the technical scope of the invention unless explicitly stated to be a limiting factor.

[0042] FIG. 1 is a diagram illustrating the overall operation of a desulfurization process water treatment system according to one embodiment of the present invention.

[0043] As illustrated in FIG. 1, the desulfurization process water treatment system of the present invention may include a desulfurization treatment unit (100) that desulfurizes exhaust gas introduced from the outside, and an electrochemical fusion desalination treatment unit (200) that desalinates the desulfurization process water introduced from the desulfurization treatment unit (100).

[0044] Here, the electrochemical fusion desalination treatment unit (200) may include an inflow raw water tank (210) that stores desalination process water flowing in from the desalination treatment unit (100), a pretreatment unit (220) that pretreats the desalination process water by desalinating ionic substances and sparingly soluble substances contained in the desalination process water using an electrochemical method that combines an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method, and a treatment water tank (230) that stores the desalination-treated water and recirculates the stored treated water to the desalination treatment unit (100).

[0045] In one embodiment, the pretreatment unit (220) pretreats the desulfurization process water by removing and decomposing insoluble substances contained in the desulfurization process water using an oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent, and simultaneously pretreats the desulfurization process water by separating and removing ionic substances contained in the desulfurization process water into cations and anions using a reverse electrodialysis treatment method, and can discharge the pretreated water to a treatment tank (230).

[0046] In another embodiment, the pretreatment unit (220) removes solids from the desulfurization process water flowing in from the inflow source water tank (210) by a sedimentation method to perform primary pretreatment, and when the primary pretreated water stored in the treatment tank (230) flows in, removes and decomposes insoluble substances contained in the primary pretreated water by an oxidation and reduction reaction treatment method using an oxidizing agent and a reducing agent to perform secondary pretreatment of the desulfurization process water, and simultaneously separates and removes ionic substances contained in the primary pretreated water into cations and anions by a reverse electrodialysis treatment method to perform secondary pretreatment of the desulfurization process water, and may discharge the secondary pretreated water to the treatment tank (230).

[0047] For example, when the pretreatment unit (220) desalinates ionic substances contained in the desulfurization process water, it applies an active radical reaction technology based on active oxygen species through an oxidation and reduction reaction treatment method to high concentrations of chloride ions (Cl) contained in the desulfurization process water. - ) is removed by converting it into the intermediate chlorine (Cl2), and residual chloride ions (Cl2) are removed through a reverse electrodialysis treatment method. - ) can be selectively separated and removed, and through a fusion treatment method including an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method, chloride ions are removed and the treated water with reduced high concentration chloride ions can be discharged to a treatment tank (230).

[0048] Here, the pretreatment unit (220) processes chloride ions (Cl) through an oxidation and reduction reaction method. - When removing ), chloride ions (Cl) are removed using an active oxygen species-based oxidation reaction. - Chloride ions can be removed by at least one of the first method of degassing by gasifying the intermediate chlorine (Cl2) and the second method of precipitating by combining the chlorine ions with the ions eluted by an electrochemical reaction to form an inorganic compound.

[0049] At this time, the pretreatment unit (220), when removing chloride ions in the first method, the first reaction formula 2Cl - + O3 + H2O → Cl 2(q) + 2OH - Chloride ions can be removed through this.

[0050] The pretreatment unit (220) removes Fe eluted by electrochemical reaction when removing chloride ions in the second method. 2+ , Fe 3+ ions are Cl - and SO4 2- When an inorganic compound is formed by combining with ions, the inorganic compound is precipitated in a rapid precipitation tank to remove the chloride ions, and the second reaction equation Fe 2+ + 2Cl - → FeCl2, 3rd reaction equation Fe 3+ + 3Cl - → FeCl3, 4th reaction equation Fe 2+ + SO4 2- → FeSO4, Reaction Equation 5 2Fe 3+ + 3SO4 2- → Fe2(SO4)3, 6th reaction equation Fe 2+ + 2OH - → Fe(OH)2, 7th reaction equation Fe 3+ + 3OH - Chloride ions can be removed via Fe(OH)3.

[0051] In addition, the pretreatment unit (220) removes residual chloride ions (Cl) through a reverse electrodialysis treatment method. - When removing ), chloride ions can be removed in at least one of the following methods: a third method of gasifying Cl2 using an electrochemical oxidation reaction, a fourth method of removing Cl2 after converting it to HOCl, and a fifth method of selectively removing chloride ions through a separation membrane.

[0052] Here, the pretreatment unit (220), when removing chloride ions in the third method, uses the 8th reaction formula 2Cl - → Cl2+ 2e - aqChloride ions are removed through, and when removing chloride ions by the fourth method, reaction equation 9 Cl2 + H2O ⇔ HOCl + HCl, reaction equation 10 HOCl ⇔ OCl + H + The chloride ions are removed through the above method, and when removing chloride ions in the fifth method, reaction equation 11 NaCl ⇔ Na + - Cl - The above chloride ions can be removed through this.

[0053] As another example, the pretreatment unit (220) desalinates insoluble substances contained in the desulfurization process water by using an active oxygen species-based activation reaction through an oxidation and reduction reaction method to desalinate NH3 and NO contained in the desulfurization process water. x Oxidative and reduction conversions are performed on (NO, NO2), and the NH4 generated from the oxidation and reduction conversion is treated via a reverse electrodialysis method. + , NO3 - , NO2 - The ions are selectively separated and removed, and the treated water from which total nitrogen (TN) has been removed through an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method can be discharged into a treatment tank (230).

[0054] Here, the pretreatment unit (220) performs the oxidation and reduction conversion of NH3, according to the 12th reaction equation NH3 + 4OH˙ → NO3 - + 3H2O + H + , Reaction Equation 13 NH3 + O3 → NO2 - + H2O, Reaction Equation 14 NO2 - + OH˙ → NO3 - NH3 is oxidatively converted through, and Reaction Scheme 15 NH3 + e - aq + H + → NH4 + NH3 can be reduced and converted through the 16th reaction equation 2NH3 + 3O2 → 2N2 + 6H2O.

[0055] In addition, the preprocessing unit (220) is NO x When performing oxidation and reduction conversions, NO through reaction equation 17 NO + O3 → NO2 + O2, reaction equation 18 NO2 + OH˙ → HNO3, and reaction equation 19 NO2 + O3 → NO3 + O2 x is subjected to oxidative conversion treatment, and reaction equation 20 NO + e - aq + H + → N2 + H2O, NO through reaction equation 21 NO2 + H2 → N2 + H2O x It can perform reduction conversion processing.

[0056] In addition, the preprocessing unit (220) is NH4 + , NO3 - , NO2 - When selectively separating and removing ions, Reaction Equation 22 NH4 + + O3→ NO2 - + H2O, Reaction Equation 23 NO2 - + O3→ NO3 - , Reaction Equation 24 NO3 - + H2O → N2+ Nitrogen oxidation reaction through O2 (NH4 + → NO3 - → Primary treatment with N2), and reaction equation 25 NO3 - + 2e - aq + 2H + → NO2 - + H2O, Reaction Equation 26 NO2 - + 6e - aq + 6H + → NO3 using an electrochemical reduction reaction via N2 + 3H2O - It is subjected to secondary treatment for removal, and nitric acid (NO3) is removed through a reduction reaction using a nanocatalyst-coated electrode. - ) can be converted into nitrogen gas (N2) for tertiary treatment through degassing.

[0057] In this way, the pretreatment unit (220), when desalting ionic substances, utilizes a radical reaction technology based on active oxygen species through a fusion technology of an oxidation and reduction reaction treatment method and a reverse electrodialysis method to produce chloride ions Cl - It is removed by converting it into the intermediate Cl2, and the remaining chloride ions Cl - When separating and concentrating anionic substances including Na, Mg, Ca, K, Fe, SO3, and NO3 using electrochemical oxidation-reduction reactions and membranes, and when desalting sparingly soluble substances, NH3 and sparingly soluble NS compounds are oxidized and reduced by active oxygen species through a fusion technology of oxidation and reduction reaction methods and reverse electrodialysis methods to convert them into easily treatable substances, and total nitrogen (TN) can be removed by degassing N2 gas by radical reactions, removing NO2 and NO3 by electrochemical oxidation reactions, and concentrating with membranes.

[0058] For example, the pretreatment unit (220) of the present invention may include an Advanced Redox Process (ARP) that performs an oxidation and reduction reaction treatment method and an Electrodialysis Reversal (EDR) that performs a reverse electrodialysis treatment method.

[0059] Here, each of the ARP and EDR may be configured with an inlet pipe through which desulfurization process water flows in from the treatment tank (230) and an outlet pipe through which pre-treated water is discharged to the treatment tank (230).

[0060] Next, the treatment tank (230) can provide desulfurization process water to ARP and EDR respectively when desulfurization process water flows in from the inflow source tank (210), and can store the pretreated treatment water flowing in from ARP and EDR when ARP and EDR pre-treat the desulfurization process water.

[0061] As another example, the pretreatment unit (220) of the present invention may include an LC (Lamella Clarifier) ​​that removes solids from desulfurization process water by a precipitation method for primary pretreatment, an ARP (Advanced Redox Process) that performs primary pretreatment of treated water by an oxidation and reduction reaction method for secondary pretreatment, and an EDR (Electrodialysis Reversal) that performs primary pretreatment of treated water by a reverse electrodialysis method for secondary pretreatment.

[0062] Here, LC is configured with an inlet pipe through which desulfurization process water flows in from the inlet raw water tank (210) and a discharge pipe through which the primary pre-treated water is discharged to the treatment tank (230), and ARP and EDR are each configured with an inlet pipe through which the primary pre-treated water flows in from the treatment tank (230) and a discharge pipe through which the secondary pre-treated water is discharged to the treatment tank (230).

[0063] Next, the treatment tank (230) can provide the first pre-treated water to ARP and EDR respectively when the first pre-treated water from LC flows in, and can store the second pre-treated water flowing in from ARP and EDR when ARP and EDR second pre-treated the first pre-treated water.

[0064] For example, the treatment tank (230) may include a first treatment tank for storing desalinated treated water, and a second treatment tank for recirculating the treated water to the desulfurization treatment unit (100) when the treated water stored from the first treatment tank flows in.

[0065] Here, the second treatment tank is provided with a connecting pipe through which the treated water is recirculated to the desulfurization treatment unit (100), and the connecting pipe is provided with a measuring module including an EC (Electrical Conductivity) meter, a TDS (Total Dissolved Solids) meter, a pH meter, and a DFM (Digital Flow Meter) meter, etc., to measure the electrical conductivity, total dissolved solids, pH state, flow rate, etc. of the treated water.

[0066] Meanwhile, the desulfurization treatment unit (100) can desulfurize the incoming exhaust gas, dehydrate the gypsum slurry generated through the desulfurization treatment, and store the dehydrated liquid to provide to the incoming raw water tank (210).

[0067] Here, the desulfurization treatment unit (100) can remove sulfur dioxide contained in the exhaust gas by spraying limestone slurry when exhaust gas containing sulfur dioxide is introduced into the unit during desulfurization treatment.

[0068] And, the desulfurization treatment unit (100) can dehydrate the gypsum slurry corresponding to the desulfurization treatment when it is stored, separate the dehydrated liquid and the gypsum, store the separated dehydrated liquid in a dehydrated liquid storage tank, and discard the separated gypsum to the outside.

[0069] Here, the dehydrated liquid storage tank can discharge a portion of the dehydrated liquid treated with dehydration treatment to the inflow raw water tank (210) and discharge another portion of the dehydrated liquid to an external wastewater treatment unit.

[0070] In this way, the present invention can suppress equipment corrosion, extend equipment lifespan, prevent water pollution, and reduce treatment costs by recirculating desulfurization process water through an electrochemical method that combines an oxidation and reduction reaction treatment method with a reverse electrodialysis treatment method.

[0071] In addition, as an economic benefit, the present invention can reduce operating costs and industrial water usage for desulfurization wastewater treatment facilities, reduce maintenance costs for desulfurization facilities due to corrosion, ensure the quality of desulfurization gypsum, and stably generate revenue from by-products.

[0072] In addition, as a technical effect, the present invention enables safe operation of power generation facilities and desulfurization facilities, reduces industrial water usage through stable management of absorption tower slurry, and can be applied to solve maintenance and operation problems of desulfurization treatment water recycling facilities.

[0073] In addition, as a managerial effect, the present invention can comply with the government's resource circulation policy by reducing industrial water usage, enhance the image of an eco-friendly company through certification of new environmental technology, and fulfill a mutually beneficial social role by developing environmental conservation projects with small and medium-sized enterprises.

[0074] FIG. 2 is a diagram illustrating the operation of a desulfurization treatment unit of a desulfurization process water treatment system according to one embodiment of the present invention.

[0075] As illustrated in FIG. 2, the desulfurization treatment unit (100) of the desulfurization process water treatment system may include a desulfurization absorption tower (110) for desulfurizing incoming exhaust gas, a gypsum dewatering unit (120) for dewatering a gypsum slurry generated from the desulfurization absorption tower (110), and a dewatering liquid storage tank (130) for storing the dewatered liquid from the gypsum dewatering unit (120) and supplying it to the incoming raw water tank of the electrochemical fusion desalination treatment unit (200).

[0076] Here, the desulfurization absorption tower (110) can remove sulfur dioxide contained in the exhaust gas by spraying limestone slurry when exhaust gas containing sulfur dioxide flows into it.

[0077] And, the desulfurization absorption tower (110) is provided with a connecting pipe connected to the gypsum dewatering section (120), and when gypsum slurry corresponding to the desulfurization treatment is stored at the bottom, the gypsum slurry can be discharged to the gypsum dewatering section (120) through the connecting pipe.

[0078] Next, the gypsum dewatering unit (120) is configured with a connecting pipe connected to a dewatering liquid storage tank (130), and dewaters the gypsum slurry flowing in from the desulfurization absorption tower (110) to separate the dewatering liquid and gypsum, discharges the separated dewatering liquid to the dewatering liquid storage tank (130) through the connecting pipe, and can dispose of the separated gypsum to the outside.

[0079] Next, the dewatering liquid storage tank (130) is provided with a first connecting pipe connected to the inflow raw water tank of the electrochemical fusion desalination treatment unit (200), and can discharge a portion of the dewatering liquid flowing in from the gypsum dewatering unit (120) to the inflow raw water tank of the electrochemical fusion desalination treatment unit (200) through the first connecting pipe, and discharge another portion of the dewatering liquid to an external wastewater treatment unit.

[0080] Here, the dehydrated liquid storage tank (130) can be controlled so that the amount of dehydrated liquid discharged to the influent raw water tank of the electrochemical fusion desalination treatment unit (200) is greater than the amount of dehydrated liquid discharged to the wastewater treatment unit.

[0081] Additionally, the dehydrated liquid storage tank (130) may further have a second connecting pipe connected to the treatment tank of the electrochemical fusion desalination treatment unit (200), and may store recirculated treated water flowing in from the treatment tank of the electrochemical fusion desalination treatment unit (200) through the second connecting pipe.

[0082] Additionally, the dehydrated liquid storage tank (130) may include a plurality of storage tanks, and the plurality of storage tanks may be connected in parallel through a connecting pipe through which the dehydrated liquid is moved.

[0083] FIGS. 3 and 4 are drawings for explaining the operation of a pretreatment unit of a desulfurization process water treatment system according to one embodiment of the present invention, and the pretreatment unit of the present invention can be performed in two ways.

[0084] FIG. 3 is a drawing showing the configuration of a preprocessing unit according to the first embodiment of the present invention, and FIG. 4 is a drawing showing the configuration of a preprocessing unit according to the second embodiment of the present invention.

[0085] As illustrated in FIG. 3, the pretreatment unit (220) of the first embodiment of the present invention may include an oxidation and reduction reaction treatment unit (222) that pretreats the desulfurization process water by removing and decomposing insoluble substances contained in the desulfurization process water using an oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent, and discharges the pretreated water to a treatment tank (230); and a reverse electrodialysis unit (224) that pretreats the desulfurization process water by separating and removing ionic substances contained in the desulfurization process water into cations and anions using a reverse electrodialysis treatment method, and discharges the pretreated water to a treatment tank (230).

[0086] For example, the oxidation and reduction reaction processing unit (222) may include an Advanced Redox Process (ARP), and the reverse electrodialysis unit (224) may include an Electrodialysis Reversal (EDR), but this is only one example and is not limited thereto.

[0087] The oxidation and reduction reaction treatment unit (222) can decompose at least a portion of the organic matter contained in the desulfurization process water and remove at least a portion of the salt contained in the desulfurization process water by gasifying it through an oxidation and reduction reaction using an oxidizing agent and a reducing agent.

[0088] In some cases, the oxidation and reduction reaction treatment unit (222) may perform oxidation and reduction reaction treatment by simultaneously carrying out an oxidation reaction by an oxidizing agent and a reduction reaction by a reducing agent.

[0089]

[0090] In addition, the reverse electrodialysis unit (224) can separate and remove salts contained in the desulfurization process water into cations and anions, and remove scale and contamination formed on the cation exchange membrane and anion exchange membrane by reversing the polarity of the electrodes at regular intervals.

[0091] The pretreatment unit (220) of the first embodiment of the present invention, when desalinating ionic substances contained in the desulfurization process water, applies an active radical reaction technology based on active oxygen species through the oxidation and reduction reaction treatment unit (222) to high concentration chloride ions (Cl) contained in the desulfurization process water. - ) is converted into intermediate chlorine (Cl2) to remove it, and residual chloride ions (Cl2) are removed through the reverse electrodialysis unit (224). - ) can be selectively separated and removed, and the chloride ions are removed through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224), allowing the treated water with reduced high concentration chloride ions to be discharged into the treatment tank (230).

[0092] Here, the pretreatment unit (220) receives chloride ions (Cl through the oxidation and reduction reaction treatment unit (222)). - When removing ), chloride ions (Cl) are removed using an active oxygen species-based oxidation reaction. - Chloride ions can be removed by at least one of the first method of degassing by gasifying the intermediate chlorine (Cl2) and the second method of precipitating by combining the chlorine ions with the ions eluted by an electrochemical reaction to form an inorganic compound.

[0093] For example, when the pretreatment unit (220) removes chloride ions in the first manner, it can remove chloride ions through the following reaction equation 1.

[0094] Reaction Equation 1

[0095] 2Cl - + O3 + H2O → Cl 2(q) + 2OH-

[0096] As another example, the pretreatment unit (220) removes Fe eluted by electrochemical reaction when removing chloride ions in the second manner. 2+ , Fe 3+ ions are Cl - and SO4 2- When an inorganic compound is formed by combining with ions, the inorganic compound is precipitated in a rapid precipitation tank to remove chloride ions, and chloride ions can be removed through the following reaction equation 2-7.

[0097] Reaction Equation 2

[0098] Fe 2+ + 2Cl - → FeCl2

[0099] Reaction Equation 3

[0100] Fe 3+ + 3Cl - → FeCl3

[0101] Reaction Equation 4

[0102] Fe 2+ + SO4 2- → FeSO4

[0103] Reaction Equation 5

[0104] 2Fe 3+ + 3SO4 2- → Fe2(SO4)3

[0105] Reaction Equation 6

[0106] Fe 2+ + 2OH - → Fe(OH)2

[0107] Reaction Equation 7

[0108] Fe 3+ + 3OH - → Fe(OH)3

[0109] In addition, the pretreatment unit (220) removes residual chloride ions (Cl through the reverse electrodialysis unit (224) -When removing ), chloride ions can be removed in at least one of the following methods: a third method of gasifying Cl2 using an electrochemical oxidation reaction, a fourth method of removing Cl2 after converting it to HOCl, and a fifth method of selectively removing chloride ions through a separation membrane.

[0110] For example, when the pretreatment unit (220) removes chloride ions in the third method, it can remove chloride ions through the following reaction equation 8.

[0111] Reaction Equation 8

[0112] 2Cl - → Cl2+ 2e - aq

[0113] As another example, when the pretreatment unit (220) removes chloride ions in the fourth method, it can remove chloride ions through the following reaction equations 9-10.

[0114] Reaction Equation 9

[0115] Cl2 + H2O ⇔ HOCl + HCl

[0116] Reaction Equation 10

[0117] HOCl ⇔ OCl+H +

[0118] As another example, the pretreatment unit (220) can remove chloride ions through the following reaction equation 11 when removing chloride ions in the fifth method.

[0119] Reaction Equation 11

[0120] NaCl ⇔ Na + - Cl -

[0121] Next, the pretreatment unit (220) of the first embodiment of the present invention, when desalting insoluble substances contained in the desulfurization process water, utilizes an active oxygen species-based activation reaction through the oxidation and reduction reaction treatment unit (222) to remove NH3 and NO contained in the desulfurization process water. x(NO, NO2) undergoes oxidation and reduction conversion, and NH4 generated from the oxidation and reduction conversion is passed through the reverse electrodialysis unit (224). + , NO3 - , NO2 - Ions are selectively separated and removed, and the treated water from which total nitrogen (TN) has been removed through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) can be discharged to the treatment tank (230).

[0122] Here, when the pretreatment unit (220) performs oxidation and reduction conversion of NH3, it can oxidize and convert NH3 through the following reaction equation 12-14 and reduce and convert NH3 through the following reaction equation 15-16.

[0123] Reaction Equation 12

[0124] NH3 + 4OH⁻ → NO₃ - + 3H2O + H +

[0125] Reaction Equation 13

[0126] NH3 + O3 → NO2 - + H2O

[0127] Reaction Equation 14

[0128] NO2 - + OH˙ → NO3 -

[0129] Reaction Equation 15

[0130] NH3+ e - aq + H + → NH4 +

[0131] Reaction Equation 16

[0132] 2NH3 + 3O2 → 2N2 + 6H2O

[0133] In addition, the preprocessing unit (220) is NO x When performing oxidation and reduction conversions of, NO through the following reaction schemes 17–19 xis subjected to oxidative conversion treatment, and NO through the following reaction schemes 20-21 x It can perform reduction conversion processing.

[0134] Reaction Equation 17

[0135] NO + O3 → NO2 + O2

[0136] Reaction Equation 18

[0137] NO2 + OH˙ → HNO3

[0138] Reaction Equation 19

[0139] NO2 + O3 → NO3 + O2

[0140] Reaction Equation 20

[0141] NO + e - aq + H + → N2 + H2O

[0142] Reaction Equation 21

[0143] NO2 + H2 → N2 + H2O

[0144] In addition, the preprocessing unit (220) is NH4 + , NO3 - , NO2 - When selectively separating and removing ions, the nitrogen oxidation reaction (NH4) is performed through the following reaction schemes 22-24. + → NO3 - → First treatment with N2), and NO3 using an electrochemical reduction reaction via reaction equations 25-26 below - It is treated as a secondary process by removal, and nitric acid (NO3) is removed through a reduction reaction using a nanocatalyst-coated electrode. - ) can be converted into nitrogen gas (N2) for tertiary treatment through degassing.

[0145] Reaction Equation 22

[0146] NH4 + + O3→ NO2 - + H2O

[0147] Reaction Equation 23

[0148] NO2 - + O3→ NO3-

[0149] Reaction Equation 24

[0150] NO3 - + H2O → N2 + O2

[0151] Reaction Equation 25

[0152] NO3 - + 2e - aq + 2H + → NO2 - + H2O

[0153] Reaction Equation 26

[0154] NO2 - + 6e - aq + 6H + → N2 + 3H2O

[0155] Thus, the pretreatment unit (220) of the first embodiment of the present invention, when desalting an ionic substance, utilizes a radical reaction technology based on active oxygen species through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) to desalt chloride ions Cl - It is removed by converting it into the intermediate Cl2, and the remaining chloride ions Cl - Positive and negative ionic substances including Na, Mg, Ca, K, Fe, SO3, and NO3 can be separated and concentrated using electrochemical redox reactions and a separation membrane.

[0156] In addition, the pretreatment unit (220) of the first embodiment of the present invention, when desalting a sparingly soluble substance, can convert NH3 and sparingly soluble NS compounds into easily treatable substances by oxidizing and reducing them with active oxygen species through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224), and can remove total nitrogen (TN) by degassing N2 gas by radical reaction, removing NO2 and NO3 by electrochemical oxidation reaction, and concentrating with a separation membrane.

[0157] Additionally, the oxidation and reduction reaction treatment unit (222) may each have a first inlet pipe through which desulfurization process water flows in from the treatment tank (230) and a first discharge pipe through which pre-treated water is discharged to the treatment tank (230).

[0158] Additionally, the reverse electrodialysis unit (224) may be configured with a second inlet pipe through which desulfurization process water flows in from the treatment tank (230) and a second outlet pipe through which pre-treated water is discharged to the treatment tank (230).

[0159] Here, the treatment tank (230) supplies desulfurization process water to the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) respectively when desulfurization process water flows in from the inflow source tank, and when the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) pre-treat the desulfurization process water, it can store the pre-treated water flowing in from the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224).

[0160] Meanwhile, as illustrated in FIG. 4, the pretreatment unit (220) of the second embodiment of the present invention comprises: a solid sedimentation unit (226) that removes solids from the desulfurization process water flowing in from the inflow raw water tank by a sedimentation method and discharges the first pretreated treated water to the treatment tank (230); an oxidation and reduction reaction treatment unit (222) that, when the first pretreated treated water stored in the treatment tank (230) flows in, removes and decomposes insoluble substances contained in the first pretreated treated water by an oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent to perform second pretreatment and discharges the second pretreated treated water to the treatment tank (230); and a reverse electrodialysis treatment unit that, when the first pretreated treated water stored in the treatment tank (230) flows in, separates and removes ionic substances contained in the first pretreated treated water into cations and anions by a reverse electrodialysis treatment method to perform second pretreatment and discharges the second pretreated treated water to the treatment tank (230). It may include a dialysis unit (224).

[0161] For example, the solid sedimentation unit (226) may include an LC (Lamella Clarifier), the oxidation and reduction reaction treatment unit (222) may include an ARP (Advanced Redox Process), and the reverse electrodialysis unit (224) may include an EDR (Electrodialysis Reversal).

[0162] The pretreatment unit (220) of the second embodiment of the present invention, when desalting ionic substances contained in the first pretreated water, applies an active radical reaction technology based on active oxygen species through the oxidation and reduction reaction treatment unit (222) to the high concentration of chloride ions (Cl) contained in the first pretreated water. - ) is converted into intermediate chlorine (Cl2) to remove it, and residual chloride ions (Cl2) are removed through the reverse electrodialysis unit (224). - ) can be selectively separated and removed, and the chloride ions are removed through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224), allowing the treated water with reduced high concentration chloride ions to be discharged into the treatment tank (230).

[0163] Here, the pretreatment unit (220) receives chloride ions (Cl through the oxidation and reduction reaction treatment unit (222)). - When removing ), chloride ions (Cl) are removed using an active oxygen species-based oxidation reaction. - Chloride ions can be removed by at least one of the first method of degassing by gasifying the intermediate chlorine (Cl2) and the second method of precipitating by combining the chlorine ions with the ions eluted by an electrochemical reaction to form an inorganic compound.

[0164] In addition, the pretreatment unit (220) removes residual chloride ions (Cl through the reverse electrodialysis unit (224) -When removing ), chloride ions can be removed in at least one of the following methods: a third method of gasifying Cl2 using an electrochemical oxidation reaction, a fourth method of removing Cl2 after converting it to HOCl, and a fifth method of selectively removing chloride ions through a separation membrane.

[0165] Next, the pretreatment unit (220) of the second embodiment of the present invention, when desalting sparingly soluble substances contained in the first pretreated water, utilizes an active oxygen species-based activation reaction through the oxidation and reduction reaction treatment unit (222) to remove NH3 and NO contained in the first pretreated water. x (NO, NO2) undergoes oxidation and reduction conversion, and NH4 generated by oxidation and reduction conversion is obtained through the reverse electrodialysis unit (224). + , NO3 - , NO2 - Ions are selectively separated and removed, and the treated water from which total nitrogen (TN) has been removed through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) can be discharged to the treatment tank (230).

[0166] Thus, the pretreatment unit (220) of the second embodiment of the present invention, when desalting an ionic substance, utilizes a radical reaction technology based on active oxygen species through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) to desalt chloride ions Cl - It is removed by converting it into the intermediate Cl2, and the remaining chloride ions Cl - Positive and negative ionic substances including Na, Mg, Ca, K, Fe, SO3, and NO3 can be separated and concentrated using electrochemical redox reactions and a separation membrane.

[0167] In addition, the pretreatment unit (220) of the second embodiment of the present invention, when desalting a sparingly soluble substance, can convert NH3 and sparingly soluble NS compounds into easily treatable substances by oxidizing and reducing them with active oxygen species through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224), and can remove total nitrogen (TN) by degassing N2 gas by radical reaction, removing NO2 and NO3 by electrochemical oxidation reaction, and concentrating with a separation membrane.

[0168] Additionally, the oxidation and reduction reaction treatment unit (222) may have a first inlet pipe through which the first pre-treated water from the treatment tank (230) flows in, and a first discharge pipe through which the second pre-treated water is discharged to the treatment tank (230).

[0169] And, the reverse electrodialysis unit (224) may each have a second inlet pipe through which the first pre-treated treated water from the treatment tank (230) flows in, and a second outlet pipe through which the second pre-treated treated water is discharged to the treatment tank (230).

[0170] Here, the treatment tank (230) can provide the primary pretreated water to the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) respectively when the primary pretreated water from the solid sedimentation tank (226) flows in, and can store the secondary pretreated water flowing in from the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) when the primary pretreated water from the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) undergoes secondary pretreatment.

[0171] FIG. 5 is a diagram illustrating the overall operation of a desulfurization process water treatment system according to another embodiment of the present invention.

[0172] As illustrated in FIG. 5, the desulfurization process water treatment system (100) of the present invention may include a desulfurization treatment unit (100) that desulfurizes exhaust gas introduced from the outside, and an electrochemical fusion desalination treatment unit (200) that desalinates the desulfurization process water introduced from the desulfurization treatment unit (100).

[0173] Here, the electrochemical fusion desalination treatment unit (200) may include an inflow raw water tank (210) that stores desalination process water flowing in from the desalination treatment unit (100), a pretreatment unit (220) that pretreats the desalination process water by desalinating ionic substances and sparingly soluble substances contained in the desalination process water using an electrochemical method that combines an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method, a treatment water tank (230) that stores the desalination-treated water and recirculates the stored treatment water to the desalination treatment unit (100), and a post-treatment unit (240) that post-treats the treatment water stored in the treatment water tank (230) using at least one of a reverse electrodialysis treatment method and a capacitive desalination treatment method and discharges the post-treated treatment water to the treatment water tank (230).

[0174] For example, the post-processing unit (240) may include at least one of an Electrodialysis Reversal (EDR) that performs a reverse electrodialysis treatment method and a Capacitive Deionization (CDI) that performs a capacitive deionization treatment method.

[0175] Additionally, the electrochemical fusion desalination treatment unit (200) may further include a discharge tank (250) that stores wastewater discharged from the influent raw water tank (210) and the pretreatment unit (220) and discharges the stored wastewater to a wastewater treatment plant.

[0176] Additionally, the treatment tank (230) can provide the first pre-treated water to ARP and EDR respectively when the first pre-treated water from LC flows in, and can store the second pre-treated water flowing in from ARP and EDR when ARP and EDR second pre-treated the first pre-treated water.

[0177] For example, the treatment tank (230) may include a first treatment tank for storing desalinated treated water, and a second treatment tank for recirculating the treated water to the desulfurization treatment unit (100) when the treated water stored from the first treatment tank flows in.

[0178] Here, the second treatment tank is provided with a connecting pipe through which the treated water is recirculated to the desulfurization treatment unit (100), and the connecting pipe is provided with a measuring module including an EC (Electrical Conductivity) meter, a TDS (Total Dissolved Solids) meter, a pH meter, and a DFM (Digital Flow Meter) meter, etc., to measure the electrical conductivity, total dissolved solids, pH state, flow rate, etc. of the treated water.

[0179] Additionally, the second treatment tank is connected to a post-treatment unit (240) that post-treats the treated water through a discharge pipe and an inflow pipe, and when the treated water is discharged to the post-treatment unit (240) through the discharge pipe, the post-treated treated water from the post-treatment unit (240) can be introduced through the inflow pipe.

[0180] And, as an example of one embodiment, the pretreatment unit (220) pretreats the desulfurization process water by removing and decomposing insoluble substances contained in the desulfurization process water using an oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent, and simultaneously pretreats the desulfurization process water by separating and removing ionic substances contained in the desulfurization process water into cations and anions using a reverse electrodialysis treatment method, and can discharge the pretreated water to the treatment tank (230).

[0181] In another embodiment, the pretreatment unit (220) removes solids from the desulfurization process water flowing in from the inflow source water tank (210) by a sedimentation method to perform primary pretreatment, and when the primary pretreated water stored in the treatment tank (230) flows in, removes and decomposes insoluble substances contained in the primary pretreated water by an oxidation and reduction reaction treatment method using an oxidizing agent and a reducing agent to perform secondary pretreatment of the desulfurization process water, and simultaneously separates and removes ionic substances contained in the primary pretreated water into cations and anions by a reverse electrodialysis treatment method to perform secondary pretreatment of the desulfurization process water, and may discharge the secondary pretreated water to the treatment tank (230).

[0182] The desulfurization process water treatment system according to the embodiment of FIG. 5 has only a post-treatment unit (240) added as a component that post-treats the treated water stored in the treatment tank (230) using at least one of a reverse electrodialysis treatment method and a capacitive desalination treatment method, and the remaining components and operations are the same as the desulfurization process water treatment system according to the embodiment of FIG. 1, so a detailed description is omitted.

[0183] Figure 6 is a diagram illustrating the desulfurization process water treatment process of the desulfurization process water treatment system of Figure 1.

[0184] As illustrated in FIG. 6, in the desulfurization process water treatment system of the present invention, the desulfurization absorption tower (110) can perform a desulfurization treatment by injecting a limestone slurry when exhaust gas containing sulfur dioxide is introduced into it to remove sulfur dioxide contained in the exhaust gas.

[0185] And, the desulfurization absorption tower (110) can discharge the gypsum slurry to the gypsum dewatering section (120) through a connecting pipe when the gypsum slurry is stored at the bottom through desulfurization treatment.

[0186] Next, the gypsum dewatering unit (120) dewaters the gypsum slurry flowing in from the desulfurization absorption tower (110) to separate the filtered water and gypsum, discharges the separated filtered water to the dewatering liquid storage tank (130) through the connecting pipe, and can dispose of the separated gypsum to the outside.

[0187] Next, the dewatering liquid storage tank (130) can discharge a portion of the dewatering liquid flowing in from the gypsum dewatering unit (120) to the treatment tank (230) and discharge another portion of the dewatering liquid to an external wastewater treatment unit.

[0188] Here, the dehydrated liquid storage tank (130) can be controlled so that the amount of dehydrated liquid discharged to the treatment tank (230) is greater than or equal to the amount of dehydrated liquid discharged to the wastewater treatment unit.

[0189] Additionally, the dehydrated liquid storage tank (130) may store recirculated treated water flowing in from the treated water tank (230).

[0190] Additionally, the dehydrated liquid storage tank (130) may include a plurality of storage tanks, and the plurality of storage tanks may be connected in parallel through a connecting pipe through which the dehydrated liquid is moved.

[0191] And, the oxidation and reduction reaction treatment unit (222) including the ARP (Advanced Redox Process) can remove and decompose insoluble substances contained in the desulfurization process water using an oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent, thereby pre-treating the desulfurization process water and discharging the pre-treated water into a treatment tank (230).

[0192] Additionally, the reverse electrodialysis unit (224) including EDR (Electrodialysis Reversal) can pre-treat the desulfurization process water by separating and removing ionic substances contained in the desulfurization process water into cations and anions using a reverse electrodialysis treatment method, and discharge the pre-treated water into a treatment tank (230).

[0193] The present invention applies an active radical reaction technology based on active oxygen species through an oxidation and reduction reaction treatment unit (222) when desalting ionic substances contained in desulfurization process water, thereby removing high concentrations of chloride ions (Cl) contained in the desulfurization process water. - ) is converted into intermediate chlorine (Cl2) to remove it, and residual chloride ions (Cl2) are removed through the reverse electrodialysis unit (224). - ) can be selectively separated and removed, and the chloride ions are removed through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224), allowing the treated water with reduced high concentration chloride ions to be discharged into the treatment tank (230).

[0194] Here, the present invention provides chloride ions (Cl ions) through an oxidation and reduction reaction treatment unit (222). - When removing ), chloride ions (Cl) are removed using an active oxygen species-based oxidation reaction. - Chloride ions can be removed by at least one of the first method of degassing by gasifying the intermediate chlorine (Cl2) and the second method of precipitating by combining the chlorine ions with the ions eluted by an electrochemical reaction to form an inorganic compound.

[0195] In addition, the present invention, when desalting insoluble substances contained in desulfurization process water, utilizes an active oxygen species-based activation reaction through an oxidation and reduction reaction treatment unit (222) to desalt NH3 and NO contained in the desulfurization process water. x (NO, NO2) undergoes oxidation and reduction conversion, and NH4 generated from the oxidation and reduction conversion is passed through the reverse electrodialysis unit (224). + , NO3 - , NO2 - Ions are selectively separated and removed, and the treated water from which total nitrogen (TN) has been removed through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) can be discharged to the treatment tank (230).

[0196] Thus, the present invention, when desalting an ionic substance, utilizes a radical reaction technology based on active oxygen species through an oxidation and reduction reaction treatment unit (222) and a reverse electrodialysis unit (224) to desalt chloride ions Cl - It is removed by converting it into the intermediate Cl2, and the remaining chloride ions Cl - Positive and negative ionic substances including Na, Mg, Ca, K, Fe, SO3, and NO3 can be separated and concentrated using electrochemical redox reactions and a separation membrane.

[0197] In addition, when desalting a sparingly soluble substance, the present invention can convert NH3 and sparingly soluble NS compounds into easily treatable substances by oxidizing and reducing them with active oxygen species through an oxidation and reduction reaction treatment unit (222) and a reverse electrodialysis unit (224), and remove total nitrogen (TN) by degassing N2 gas by radical reaction, removing NO2 and NO3 by electrochemical oxidation reaction, and concentrating with a separation membrane.

[0198] Next, the treatment tank (230) can store the desalinated treated water and recirculate the stored treated water to a desulfurization treatment unit including a desulfurization absorption tower (110).

[0199] Figure 7 is a diagram illustrating the desulfurization process water treatment process of the desulfurization process water treatment system of Figure 5.

[0200] As illustrated in FIG. 7, in the desulfurization process water treatment system of the present invention, the desulfurization absorption tower (110) can perform a desulfurization treatment by injecting a limestone slurry when exhaust gas containing sulfur dioxide is introduced into it to remove sulfur dioxide contained in the exhaust gas.

[0201] And, the desulfurization absorption tower (110) can discharge the gypsum slurry to the gypsum dewatering section (120) through a connecting pipe when the gypsum slurry is stored at the bottom through desulfurization treatment.

[0202] Next, the gypsum dewatering unit (120) dewaters the gypsum slurry flowing in from the desulfurization absorption tower (110) to separate the filtered water and gypsum, discharges the separated filtered water to the dewatering liquid storage tank (130) through the connecting pipe, and can dispose of the separated gypsum to the outside.

[0203] Next, the dewatering liquid storage tank (130) can discharge a portion of the dewatering liquid flowing in from the gypsum dewatering unit (120) to the inflow raw water tank (210) and discharge another portion of the dewatering liquid to an external wastewater treatment unit.

[0204] Here, the dehydrated liquid storage tank (130) can be controlled so that the amount of dehydrated liquid discharged to the inflow raw water tank (230) is greater than the amount of dehydrated liquid discharged to the wastewater treatment unit.

[0205] Additionally, the dehydrated liquid storage tank (130) may store recirculated treated water flowing in from the treated water tank (230).

[0206] Additionally, the dehydrated liquid storage tank (130) may include a plurality of storage tanks, and the plurality of storage tanks may be connected in parallel through a connecting pipe through which the dehydrated liquid is moved.

[0207] And, the solid sedimentation unit (226) including LC (Lamella Clarifier) ​​can remove solids from the desulfurization process water flowing in from the inflow source water tank (210) by sedimentation and discharge the treated water, which has been pretreated in the first stage, to the first treatment tank (232).

[0208] Next, the first treatment tank (232) can provide the first pretreated water to the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) respectively when the first pretreated water from the solid sedimentation tank (226) flows in, and can store the second pretreated water flowing in from the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) when the first pretreated water from the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) undergoes second pretreatment.

[0209] Here, the oxidation and reduction reaction treatment unit (222) including the Advanced Redox Process (ARP) can pre-treat the desulfurization process water by removing and decomposing insoluble substances contained in the desulfurization process water using an oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent, and discharge the pre-treated water to the first treatment tank (232).

[0210] Additionally, the reverse electrodialysis unit (224) including EDR (Electrodialysis Reversal) can pre-treat the desulfurization process water by separating and removing ionic substances contained in the desulfurization process water into cations and anions using a reverse electrodialysis treatment method, and discharge the pre-treated water to the first treatment tank (232).

[0211] The present invention relates to a method for desalinating ionic substances contained in primary pretreated water by applying an active radical reaction technology based on active oxygen species through an oxidation and reduction reaction treatment unit (222) to high concentration chloride ions (Cl) contained in primary pretreated water. - ) is converted into intermediate chlorine (Cl2) to remove it, and residual chloride ions (Cl2) are removed through the reverse electrodialysis unit (224). - ) can be selectively separated and removed, and the chloride ions are removed through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224), so that the treated water with reduced high concentration chloride ions can be discharged to the first treatment tank (232).

[0212] Here, the present invention provides chloride ions (Cl ions) through an oxidation and reduction reaction treatment unit (222). - When removing ), chloride ions (Cl) are removed using an active oxygen species-based oxidation reaction. - Chloride ions can be removed by at least one of the first method of degassing by gasifying the intermediate chlorine (Cl2) and the second method of precipitating by combining the chlorine ions with the ions eluted by an electrochemical reaction to form an inorganic compound.

[0213] In addition, the present invention [describes] residual chloride ions (Cl₂) through a reverse electrodialysis unit (224). - When removing ), chloride ions can be removed in at least one of the following methods: a third method of gasifying Cl2 using an electrochemical oxidation reaction, a fourth method of removing Cl2 after converting it to HOCl, and a fifth method of selectively removing chloride ions through a separation membrane.

[0214] Next, the present invention, when desalting sparingly soluble substances contained in primary pretreated water, utilizes an active oxygen species-based activation reaction through an oxidation and reduction reaction treatment unit (222) to remove NH3 and NO contained in the primary pretreated water. x (NO, NO2) undergoes oxidation and reduction conversion, and NH4 generated by oxidation and reduction conversion is obtained through the reverse electrodialysis unit (224). + , NO3 - , NO2 - Ions are selectively separated and removed, and the treated water from which total nitrogen (TN) has been removed through the oxidation and reduction reaction treatment unit (222) and the reverse electrodialysis unit (224) can be discharged to the first treatment tank (232).

[0215] The present invention, when desalting an ionic substance, utilizes a radical reaction technology based on active oxygen species through an oxidation and reduction reaction treatment unit (222) and a reverse electrodialysis unit (224) to desalt chloride ions Cl - It is removed by converting it into the intermediate Cl2, and the remaining chloride ions Cl - Positive and negative ionic substances including Na, Mg, Ca, K, Fe, SO3, and NO3 can be separated and concentrated using electrochemical redox reactions and a separation membrane.

[0216] In addition, when desalting a sparingly soluble substance, the present invention can convert NH3 and sparingly soluble NS compounds into easily treatable substances by oxidizing and reducing them with active oxygen species through an oxidation and reduction reaction treatment unit (222) and a reverse electrodialysis unit (224), and remove total nitrogen (TN) by degassing N2 gas by radical reaction, removing NO2 and NO3 by electrochemical oxidation reaction, and concentrating with a separation membrane.

[0217] Next, the first treatment tank (232) stores the second pre-treated water, and the second treatment tank (234) can recirculate the treated water to the desulfurization treatment unit (100) when the treated water stored from the first treatment tank (232) flows in.

[0218] Here, the second treatment tank (234) is provided with a connecting pipe through which the treated water is recirculated to the desulfurization treatment unit (100), and the connecting pipe is provided with a measuring module including an EC (Electrical Conductivity) meter, a TDS (Total Dissolved Solids) meter, a pH meter, and a DFM (Digital Flow Meter) meter, etc., to measure the electrical conductivity, total dissolved solids, pH state, flow rate, etc. of the treated water.

[0219] Additionally, the second treatment tank (234) is connected to a post-treatment unit (240) that post-treats the treated water through a discharge pipe and an inflow pipe, and when the treated water is discharged to the post-treatment unit (240) through the discharge pipe, the post-treated treated water from the post-treatment unit (240) can be introduced through the inflow pipe.

[0220] Next, the post-treatment unit (240) can post-treat the treated water stored in the second treatment tank (234) using at least one of the reverse electrodialysis treatment method and the capacitive desalination treatment method, and discharge the post-treated treated water to the second treatment tank (234).

[0221] For example, the post-processing unit (240) may include at least one of an Electrodialysis Reversal (EDR) that performs a reverse electrodialysis treatment method and a Capacitive Deionization (CDI) that performs a capacitive deionization treatment method.

[0222] Additionally, the electrochemical fusion desalination treatment unit (200) may further include a discharge tank (250) that stores wastewater discharged from the influent raw water tank (210) and the pretreatment unit, and discharges the stored wastewater to a wastewater treatment plant.

[0223] Additionally, the first treatment tank (232) can provide the first pre-treated water to ARP and EDR respectively when the first pre-treated water from LC flows in, and can store the second pre-treated water flowing in from ARP and EDR when ARP and EDR perform the first pre-treated water.

[0224] FIGS. 8 and 9 are drawings for illustrating treatment result data of a desulfurization process water treatment system according to one embodiment of the present invention.

[0225] As illustrated in FIG. 8, the present invention applies an active radical reaction technology based on active oxygen species through an oxidation and reduction reaction treatment method to high concentrations of chloride ions (Cl) contained in desulfurization process water. - ) is removed by converting it into the intermediate chlorine (Cl2), and residual chloride ions (Cl2) are removed through a reverse electrodialysis treatment method. - By selectively separating and removing ), it can be seen that the concentration (ppm) of chloride ions contained in the desulfurization process water and the amount of chloride ions removed (kg / h) gradually decrease over time.

[0226] In addition, as illustrated in FIG. 9, the present invention utilizes an active oxygen species-based activation reaction through an oxidation and reduction reaction treatment method to remove NH3 and NO contained in the desulfurization process water. x Oxidative and reduction conversions are performed on (NO, NO2), and the NH4 generated from the oxidation and reduction conversion is treated via a reverse electrodialysis method. + , NO3 - , NO2 - By selectively separating and removing ions, it can be seen that the total nitrogen (TN) concentration (ppm) and total nitrogen removal amount (kg / h) contained in the desulfurization process water gradually decrease over time.

[0227] Accordingly, the present invention can suppress equipment corrosion, extend equipment lifespan, prevent water pollution, and reduce treatment costs by desalinating and recirculating desulfurization process water using an electrochemical method that combines an oxidation and reduction reaction treatment method with a reverse electrodialysis treatment method.

[0228]

[0229] FIG. 10 is a flowchart illustrating a method for treating desulfurization process water of a desulfurization process water treatment system according to one embodiment of the present invention.

[0230] As illustrated in FIG. 10, the present invention can desulfurize exhaust gas introduced from the outside (S10).

[0231] Next, the present invention can collect and store the desulfurization process water generated through the desulfurization treatment (S20).

[0232] Next, the present invention can pre-treat desulfurization process water by desalinating ionic substances and sparingly soluble substances contained in the desulfurization process water using an electrochemical method that combines an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method (S30).

[0233] Here, the present invention can pre-treat desulfurization process water by removing and decomposing sparingly soluble substances contained in the desulfurization process water using an oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent, and simultaneously pre-treat desulfurization process water by separating and removing ionic substances contained in the desulfurization process water into cations and anions using a reverse electrodialysis treatment method.

[0234] In some cases, the present invention may first pretreat the desulfurization process water by removing solids from the incoming water through a sedimentation method, and when the first pretreated water is introduced, the desulfurization process water may be second pretreated by removing and decomposing insoluble substances contained in the first pretreated water through an oxidation and reduction reaction treatment method using an oxidizing agent and a reducing agent, and simultaneously second pretreat the desulfurization process water by separating and removing ionic substances contained in the first pretreated water into cations and anions through a reverse electrodialysis treatment method.

[0235] And, the present invention can store pre-treated water (S40).

[0236] Herein, the present invention may further perform post-treatment on the stored treated water using at least one of a reverse electrodialysis treatment method and a capacitive desalination treatment method.

[0237] Next, the present invention can recirculate the stored treated water (S50).

[0238] Next, the present invention checks whether a request to terminate the desulfurization process water treatment process is input (S60), and if a request to terminate the desulfurization process water treatment process is input, the desulfurization process water treatment process can be terminated.

[0239] In this way, the present invention can suppress equipment corrosion, extend equipment lifespan, prevent water pollution, and reduce treatment costs by recirculating desulfurization process water through an electrochemical method that combines an oxidation and reduction reaction treatment method with a reverse electrodialysis treatment method.

[0240] In addition, as an economic benefit, the present invention can reduce operating costs and industrial water usage for desulfurization wastewater treatment facilities, reduce maintenance costs for desulfurization facilities due to corrosion, ensure the quality of desulfurization gypsum, and stably generate revenue from by-products.

[0241] In addition, as a technical effect, the present invention enables safe operation of power generation facilities and desulfurization facilities, reduces industrial water usage through stable management of absorption tower slurry, and can be applied to solve maintenance and operation problems of desulfurization treatment water recycling facilities.

[0242] In addition, as a managerial effect, the present invention can comply with the government's resource circulation policy by reducing industrial water usage, enhance the image of an eco-friendly company through certification of new environmental technology, and fulfill a mutually beneficial social role by developing environmental conservation projects with small and medium-sized enterprises.

[0243] Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art will understand that the present invention may be implemented in other specific forms without altering its technical concept or essential features. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

[0244] The present invention can be used in a wastewater treatment system that treats desulfurization process water discharged from power plants, etc.

Claims

1. A desulfurization treatment unit that desulfurizes exhaust gas flowing in from the outside; and, It includes an electrochemical fusion desalination treatment unit that desalinates the desulfurization process water flowing in from the above desulfurization treatment unit, and The above electrochemical fusion desalination treatment unit is, An inflow raw water tank for storing desulfurization process water flowing in from the above desulfurization treatment unit; A pretreatment unit that pretreats the desulfurization process water by desalinating ionic substances and sparingly soluble substances contained in the desulfurization process water using an electrochemical method that combines an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method; and, A desulfurization process water treatment system characterized by including a treatment tank that stores the desalinated treated water and recirculates the stored treated water to the desulfurization treatment unit.

2. In Paragraph 1, The above preprocessing unit is, An oxidation and reduction reaction treatment unit that removes and decomposes sparingly soluble substances contained in the desulfurization process water by the oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent, thereby pre-treating the desulfurization process water, and discharges the pre-treated water into the treatment tank; and, A desulfurization process water treatment system characterized by including a reverse electrodialysis unit that pretreats the desulfurization process water by separating and removing ionic substances contained in the desulfurization process water into cations and anions using the reverse electrodialysis treatment method described above, and discharges the pretreated water into the treatment tank.

3. In Paragraph 2, The above preprocessing unit is, When desalinating ionic substances contained in the above desulfurization process water, active radical reaction technology based on active oxygen species is applied through the oxidation and reduction reaction treatment unit to the high concentration of chloride ions (Cl) contained in the above desulfurization process water - ) is removed by converting it into the intermediate chlorine (Cl2), and Residual chloride ions (Cl through the above reverse electrodialysis unit) - Selectively separate and remove ), A desulfurization process water treatment system characterized by removing chloride ions through the above oxidation and reduction reaction treatment unit and the above reverse electrodialysis unit, and discharging the treated water with reduced high concentration chloride ions into the above treatment tank.

4. In Paragraph 2, The above preprocessing unit is, When desalinating sparingly soluble substances contained in the above desulfurization process water, NH3 and NO contained in the above desulfurization process water are treated using an active oxygen species-based activation reaction through the above oxidation and reduction reaction treatment unit. x Performs oxidation and reduction conversions of (NO, NO2), NH4 generated by the oxidation and reduction conversion through the above-mentioned reverse electrodialysis unit + , NO3 - , NO2 - It selectively separates and removes ions, A desulfurization process water treatment system characterized by discharging treated water from which total nitrogen (TN) has been removed through the above oxidation and reduction reaction treatment unit and the above reverse electrodialysis unit into the above treatment tank.

5. In Paragraph 1, The above preprocessing unit is, A solid sedimentation unit that removes solids from the desulfurization process water flowing in from the influent raw water tank using a sedimentation method and discharges the primary pretreated treated water into the treatment tank; An oxidation and reduction reaction treatment unit that, when primary pretreated water stored in the treatment tank is introduced, removes and decomposes sparingly soluble substances contained in the primary pretreated water using the oxidation and reduction reaction treatment method utilizing an oxidizing agent and a reducing agent to perform secondary pretreatment, and discharges the secondary pretreated water to the treatment tank; and, A desulfurization process water treatment system characterized by including a reverse electrodialysis unit that, when primary pretreated water stored in the treatment tank is introduced, separates and removes ionic substances contained in the secondary pretreated water into cations and anions using the reverse electrodialysis treatment method to perform secondary pretreatment, and discharges the secondary pretreated water to the treatment tank.

6. In Paragraph 1, The above treatment tank is, A first treatment tank for storing the above-mentioned desalination treated water; and, A desulfurization process water treatment system characterized by including a second treatment tank that recirculates the inflowed treated water to the desulfurization treatment unit when the treated water stored in the first treatment tank flows in.

7. In Paragraph 1, The above electrochemical fusion desalination treatment unit is, A desulfurization process water treatment system characterized by further including a post-treatment unit that post-treats the treated water stored in the treatment tank using at least one of a reverse electrodialysis treatment method and a capacitive desalination treatment method, and discharges the post-treated treated water to the treatment tank.

8. In Paragraph 1, The above electrochemical fusion desalination treatment unit is, A desulfurization process water treatment system characterized by further including a discharge tank that stores the discharge water discharged from the influent raw water tank and the pretreatment unit, and discharges the stored discharge water to a wastewater treatment plant.

9. In a method for treating desulfurization process water of a desulfurization process water treatment system, A step of desulfurizing exhaust gas introduced from the outside; A step of collecting and storing the desulfurization process water generated through the above desulfurization treatment; A step of pre-treating the desulfurization process water by desalinating ionic substances and sparingly soluble substances contained in the desulfurization process water using an electrochemical method that combines an oxidation and reduction reaction treatment method and a reverse electrodialysis treatment method; A step of storing the pre-treated water; and A method for treating desulfurization process water characterized by including a step of recirculating the stored treated water.

10. In Paragraph 9, A method for treating desulfurization process water, characterized by further including a step of post-treating the stored treated water using at least one of a reverse electrodialysis treatment method and a capacitive desalination treatment method.

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