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KR-20260064797-A - SCR SYSTEM FOR REMOVING NITROGEN OXIDES FROM LOW TEMPERATURE EXHAUST GAS

KR20260064797AKR 20260064797 AKR20260064797 AKR 20260064797AKR-20260064797-A

Abstract

An SCR system for removing nitrogen oxides from low-temperature exhaust gas according to one embodiment of the present invention comprises: a power generation unit that produces energy using diesel or biogas; a DOC/DPF treatment unit that removes particulate matter contained in the exhaust gas discharged from the power generation unit; a heat exchanger that lowers the temperature of the exhaust gas discharged from the DOC/DPF treatment unit; and an SCR treatment unit that removes nitrogen oxides contained in the exhaust gas discharged from the heat exchanger; wherein a reducing agent supply unit or an ozone supply unit may be connected to the front end of the SCR treatment unit.

Inventors

  • 최정황

Assignees

  • 주식회사 씨엠씨텍

Dates

Publication Date
20260508
Application Date
20241029

Claims (9)

  1. Power generation unit that produces energy using diesel or biogas; A DOC/DPF treatment unit for removing particulate matter contained in the exhaust gas discharged from the above-mentioned power generation unit; A heat exchanger for lowering the temperature of the exhaust gas discharged from the above DOC/DPF treatment unit; and It includes an SCR treatment unit for removing nitrogen oxides contained in the exhaust gas discharged from the heat exchanger above; A low-temperature exhaust gas nitrogen oxide removal SCR system characterized by having a reducing agent supply unit or an ozone supply unit connected to the upstream end of the above-mentioned SCR treatment unit.
  2. In paragraph 1, A low-temperature exhaust gas nitrogen oxide removal SCR system characterized by having a spray nozzle section provided in the pipe connected to the upstream end of the SCR treatment section for spraying a reducing agent supplied from the reducing agent supply section into the interior of the pipe.
  3. In paragraph 2, The above injection nozzle part is, A first injection pipe into which a reducing agent supplied from the above reducing agent supply unit is injected; A second injection pipe connected to the first injection pipe and into which air is injected; and It includes a spray nozzle located inside the above-mentioned pipe and provided at one end of the above-mentioned first injection pipe; A low-temperature exhaust gas nitrogen oxide removal SCR system characterized by the air injected into the second injection pipe and the reducing agent being heated by a heater and injected at a high temperature.
  4. In paragraph 3, A low-temperature exhaust gas nitrogen oxide removal SCR system characterized in that the temperature of the exhaust gas flowing inside the above pipe is higher than the temperature of the reducing agent injected into the first injection pipe and lower than the temperature of the air injected into the second injection pipe.
  5. In paragraph 4, A low-temperature exhaust gas nitrogen oxide removal SCR system characterized by the ozone supply unit supplying ozone to the inside of pipes connected to the upstream and downstream ends of the SCR treatment unit to induce nitrogen oxides contained in the exhaust gas to be converted into nitrogen dioxide in the first and second stages.
  6. In paragraph 5, A low-temperature exhaust gas nitrogen oxide removal SCR system characterized by the ozone supply unit supplying ozone to the inside of the pipe from behind the injection nozzle unit relative to the SCR treatment unit, or supplying ozone to the inside of the pipe between the SCR treatment unit and the injection nozzle unit.
  7. In paragraph 6, A mixing section is provided inside the piping connected to the upstream or downstream end of the above-mentioned SCR processing section, and A low-temperature exhaust gas nitrogen oxide removal SCR system characterized by the mixing section provided inside a pipe connected to the front end of the SCR treatment section being provided at the front and rear ends of the injection nozzle section, respectively.
  8. In Paragraph 7, A low-temperature exhaust gas nitrogen oxide removal SCR system characterized in that the above-mentioned mixing unit is provided in the form of a dynamic mixer capable of adjusting the operating state according to the state of the exhaust gas, ozone, or reducing agent.
  9. In any one of paragraphs 1 through 8, An SCR system for removing nitrogen oxides from low-temperature exhaust gas, characterized in that the above-described SCR treatment unit includes a catalyst comprising zeolite or tungsten and vanadium.

Description

SCR System for Removing Nitrogen Oxides from Low Temperature Exhaust Gas The present invention relates to an SCR system for removing nitrogen oxides from low-temperature exhaust gas, and more specifically, provides an SCR system for removing nitrogen oxides from low-temperature exhaust gas capable of improving the reduction efficiency of nitrogen oxides (NOx) in an exhaust gas environment in a low-temperature region. Biogas refers to hydrogen, methane, and gases produced when sewage or animal feces are decomposed using microorganisms. It is estimated that 180 million tons of biogas are produced globally. If this is converted into methane or hydrogen gas through appropriate processes, it can be utilized as an alternative resource to supplement some of the petroleum consumption. Meanwhile, discussions are currently underway regarding the introduction of a system that would mandate the production of biogas using food waste and livestock manure. Figure 1 illustrates an exemplary process of producing and utilizing biogas. Referring to FIG. 1, biogas generating sources (10) from which biogas can be obtained include human and livestock manure, food waste, agricultural and livestock waste, sewage sludge, etc. Biogas can be obtained by storing these biogas generating sources (10) in a fermentation storage unit (20) and fermenting them. The biogas obtained from the fermentation storage unit (20) can be supplied as fuel to a biogas power generation unit (30) after desulfurization treatment. The biogas power generation unit (30) can produce energy such as electricity by using biogas as fuel, that is, by burning biogas. The biogas power generation unit (30) produces energy such as electricity by burning biogas, but as a result, exhaust gas is generated. Since the exhaust gas emitted from the biogas power generation unit (30) contains harmful substances such as particulate matter like fine dust and nitrogen oxides (NOx), it is necessary to remove the harmful substances before releasing them into the atmosphere. The exhaust gas emitted from the biogas power generation unit (30) can have particulate matter such as fine dust and nitrogen oxides removed in the exhaust gas purification unit (40). However, the exhaust gas emitted when biogas is burned has a lower temperature than the exhaust gas emitted from vehicles using diesel fuel. Therefore, exhaust gas purification systems for diesel vehicles or Selective Catalyst Reduction (SCR) systems for treating diesel exhaust have limitations in removing nitrogen oxides from exhaust gas at a relatively low temperature. As such, in order to increase the utility of biogas, there is a need for technology that can improve the purification efficiency of nitrogen oxides contained in exhaust gas with an emission temperature of about 180 to 200°C. The applicant has proposed the present invention to solve the above-mentioned problems. Figure 1 is a diagram illustrating the process of producing biogas and utilizing biogas in an exemplary manner. FIG. 2 is a diagram illustrating the main configuration of a nitrogen oxide removal SCR system for low-temperature exhaust gas according to one embodiment of the present invention. FIG. 3 is a diagram illustrating the detailed configuration of a nitrogen oxide removal SCR system for low-temperature exhaust gas according to one embodiment of the present invention. Figure 4 is a diagram illustrating a modified example of the nitrogen oxide removal SCR system for low-temperature exhaust gas shown in Figure 3. Figure 5 is a drawing illustrating, in an exemplary manner, the injection nozzle section of the system shown in Figure 3. FIG. 6 is a diagram illustrating, in an exemplary manner, the mixing section of the system illustrated in FIG. 3. Hereinafter, embodiments disclosed in this specification will be described in detail with reference to the attached drawings. Identical or similar components are assigned identical or similar reference numerals, and redundant descriptions thereof will be omitted. The suffix "bu" for components used in the following description is assigned or used interchangeably solely for the ease of drafting the specification and does not inherently possess a distinct meaning or role. Furthermore, in describing embodiments disclosed in this specification, if it is determined that a detailed description of related prior art could obscure the essence of the embodiments disclosed in this specification, such detailed description will be omitted. Additionally, the attached drawings are intended only to facilitate understanding of the embodiments disclosed in this specification; the technical concept disclosed in this specification is not limited by the attached drawings, and it should be understood that they include all modifications, equivalents, and substitutions that fall within the spirit and technical scope of the present invention. Terms including ordinal numbers, such as first, second, etc., may be used to describe various compon