Patent ID: 12228485

MODE FOR INVENTION

Detailed contents of other exemplary embodiments are described in a detailed description and are illustrated in the accompanying drawings.

Various advantages and features of the present invention and methods accomplishing them will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings.

However, the present disclosure is not limited to exemplary embodiments to be described below, but may be implemented in various different forms, these exemplary embodiments will be provided only in order to make the present disclosure complete and allow those skilled in the art to completely recognize the scope of the present disclosure, and the present disclosure will be defined by the scope of the claims. Throughout the specification, like reference numerals denote like elements.

Hereinafter, an apparatus for diluting exhaust gas according to exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings.

FIG.1is a perspective view illustrating an apparatus for diluting exhaust gas according to an exemplary embodiment of the present invention,FIG.2is a cross-sectional view of the apparatus for diluting exhaust gas according to the exemplary embodiment of the present invention,FIG.3is a perspective view of a stagnant air forming unit ofFIG.2,FIG.4is a diagram illustrating experimental results of deceleration results according to a velocity of exhaust gas introduced into the stagnant air forming unit,FIG.5is an enlarged cross-sectional view illustrating an ejector unit and an adapter part ofFIG.2,FIG.6is a graph for describing an effect according to dilution temperature in the apparatus for diluting exhaust gas according to an exemplary embodiment of the present invention,FIG.7is an exemplary view illustrating a cleaning fluid supplier ofFIG.1, andFIG.8is a configuration diagram illustrating a measuring unit ofFIG.1.

The apparatus for diluting exhaust gas according to an exemplary embodiment of the present invention may be configured to include a stagnant air forming unit900, an ejector unit200and a diluting unit400. In addition, the apparatus for diluting exhaust gas may further include a cleaning fluid supplier700and a preheating unit600.

In the following description, for convenience of explanation, a front end/front end portion/front and rear end/rear end portion/rear are described based on a flow direction of the exhaust gas. That is, when the exhaust gas moves from a first point to a second point, the first point will be described as the rear end/rear end portion/rear, and the second point will be described as the front end/front end portion/front.

The stagnant air forming unit900may be connected to a rear end portion of the ejector unit200, and more specifically, may be formed in the rear end portion of the preheating unit600.

The stagnant air forming unit900forms stagnant air by decelerating exhaust gas1introduced at various flow velocities of several tens to hundreds of m/s to a velocity of several m/s or less. The velocity of the exhaust gas1introduced into the apparatus for diluting exhaust gas is not constant and may change. In particular, a flow velocity of exhaust gas in a chimney of an industrial site may variably change according to the situation. The sampled flow rate may change depending on the velocity of the exhaust gas1introduced into the apparatus for diluting exhaust gas. In order to keep the dilution ratio constant, it may be considered to control the amount of diluting air to be input differently, but it is not easy to immediately supply the amount of dilution air corresponding to the velocity. In particular, when the dilution air is supplied by being divided into primary dilution air2and secondary dilution air3by a multi-stage method as in the present invention, it may not be easier to control the amount of dilution air supplied to keep the dilution ratio constant.

Accordingly, according to the present invention, the diluting ratio may be kept constant by keeping the amount of diluting air constant and also keeping the velocity (flow rate) of exhaust gas supplied to the apparatus for diluting exhaust gas constant.

The stagnant air forming unit900may form stagnant air by rapidly decelerating the velocity even if the velocity of air introduced changes, and thus, may supply a certain amount of air to the ejector unit200to be supplied regardless of the velocity of air introduced into the stagnant air forming unit900.

As illustrated inFIG.3, the stagnant air forming unit900may be configured to include a diffuser unit910, an air retention part920and a sampling outlet part940.

The diffuser unit910has an introduction hole915through which the exhaust gas is introduced, and the radius of the passage may be formed to gradually increase along a direction in which the exhaust gas flows from the introduction hole915. Accordingly, the exhaust gas introduced through the introduction hole915has a remarkably reduced flow velocity along with a decrease in pressure and depending on the length of the diffuser unit910or the slope of the passage, the magnitude of the deceleration through the diffuser unit910may be controlled differently.

The air retention part920is formed at the front end of the diffuser unit910and is a space in which the exhaust gas decelerated by the diffuser unit910is retained. An outlet hole925is formed in the front end surface of the air retention part920, and thus, the exhaust gas which is decelerated and retained inside the air retention part920may be discharged along the flow direction. The air retention part920may be provided with a sampling outlet part940extending in a direction orthogonal to a flow direction.

The sampling outlet part940may be vertically formed on one side of the air retention part920. As described above, the air decelerated by the diffuser unit910and retained in the air retention part920is discharged through the outlet hole925, and a portion of the exhaust gas retained in the air retention part920may be discharged at a constant velocity through the sampling outlet part940extending vertically to the air retention part920.

Therefore, in the present invention, it is possible to supply a certain amount of exhaust gas to the inside of the apparatus for diluting exhaust gas regardless of the velocity of exhaust gas introduced by the stagnant air forming unit900, and thus, it is possible to sample particles while maintaining a constant dilution ratio under various flow velocity conditions.

FIG.4illustrates the experimental results of the velocity of the fluid discharged through the sampling outlet part940when fluids having different velocities are supplied to the stagnant air forming unit900through the inlet hole915, according to the present invention, and it can be confirmed that the velocity of the fluid is reduced regardless of the velocity of the fluid introduced through the inlet hole915, and thus, the fluid is discharged at a constant velocity through the sampling outlet940.

In the present invention, the exhaust gas may be an example of a measurement target, and the measurement target is not necessarily limited to the exhaust gas. For example, when the measurement target is smoke from a chimney, a passage through which a part of the smoke is absorbed may be provided in the chimney, and the smoke moving through the passage may be supplied to the stagnant air forming unit900.

The ejector unit200receives exhaust gas through the sampling outlet part940of the stagnant air forming unit900and supplies the exhaust gas to the dilution part400of the front end.

In the ejector unit200, an exhaust gas suction passage230, which is a passage through which exhaust gas is sucked and flows, may be formed to penetrate through in a central axis direction. In addition, dilution air supply passages210,211, and216may be formed so that the primary dilution air2for inducing constant velocity suction of exhaust gas is supplied onto the exhaust gas suction passage230.

As illustrated inFIG.5, the exhaust gas suction passage230may be formed by being divided into a space part231, a first suction unit232, a first accelerator233, a second suction unit234, a second accelerator235, and a diffuser236from the rear to the front.

The space part231is an introductory part where a pipe diameter is uniformly formed and exhaust gas is introduced, and a rear end of the space part231may be provided with a cover (not illustrated) sealing the space part231, and the exhaust gas may be introduced into the space part231through the cover.

The first suction unit232may be formed at the front end of the space part231and may be formed such that the inner diameter becomes smaller toward the front.

The first accelerator233may be formed at the front end of the first suction unit232, connected to the first suction unit232, and may be formed to have a constant inner diameter. The end portion212of the first branch passage to be described later may be formed to surround the first accelerator233, and the primary dilution air may be discharged forward toward the second suction unit234of the front end of the first accelerator233. As the primary dilution air2passes through the end portion212of the first branch passage having a small cross-sectional area, the flow velocity increases, and when the primary dilution air2is discharged to the second suction unit234, the pressure of the discharge port of the first accelerator233decreases. Then, a pressure difference is generated between the second suction unit234and the space part231, and the exhaust gas of the space part231may pass through the first suction unit232and the first accelerator233and may be sucked into the second suction unit234. Accordingly, in the second suction unit234, the primary dilution air2branched through the first branch passage211and the exhaust gas1are mixed to generate 1-1st dilution gas.

The second suction unit234may be formed at the front end of the first accelerator233and may be formed such that the inner diameter becomes smaller toward the front. As described above, at the rear end of the second suction unit234, the primary dilution air2may be introduced through the first branch passage211, and the exhaust gas of the space part231may be sucked into the second suction unit234due to the pressure difference caused by the introduced primary dilution air2and may be mixed with the primary dilution air.

The second accelerator235may be formed at the front end of the second suction unit234, connected to the second suction unit234and formed to have a constant inner diameter. The end portion217of the second branch passage to be described later may be formed to surround the second accelerator235, and the primary dilution air may be discharged forward toward the diffuser236of the front end of the second accelerator235. As the primary dilution air2passes through the end portion217of the second branch passage having a small cross-sectional area, the flow velocity increases, and when the primary dilution air2is discharged to the front of the second suction unit235, the pressure decreases. Then, the pressure difference is generated between the front of the second accelerator235and the second suction unit234, and the 1-1st dilution gas of the second suction unit234passes through the second accelerator235and moves to the diffuser236of the front of the second accelerator235. Accordingly, in the diffuser236, the 1-1st dilution gas and the branched and supplied primary dilution air2are mixed to produce 1-2nd dilution gas.

As described above, the dilution air supply passages210,211, and216may be formed in the ejector unit200. The dilution air supply passages210,211, and216are generally formed to penetrate through the radial direction and branch and supply the primary dilution air2on the exhaust gas suction passage230.

A first pipe221guiding the introduction of the primary dilution air2from the outside may be coupled to the dilution air supply passages210,211, and216.

In the present invention, the dilution air supply passage may be configured to include a main passage210, a first branch passage211, and a second branch passage216. The main passage210is coupled to the first pipe221to introduce the primary dilution air2from the outside.

The first branch passage211and the second branch passage216are branched from the main passage210and supplies the primary dilution air2to the exhaust gas suction passage230. The end portion212of the branched first branch passage may be formed to surround the first accelerator233to jet the primary dilution air2branched toward the second suction unit234of the front end of the first accelerator233. In addition, the end portion217of the branched second branch passage may be formed to surround the second accelerator235to jet the primary dilution air2branched toward the diffuser236of the front end of the second accelerator235.

As described above, in the present invention, the primary dilution air2is branched into two stages within the ejector unit200and discharged onto the exhaust gas suction passage230to suck the exhaust gas located at the rear of the ejector unit200.

In this exemplary embodiment, a description will be given of a form branched into two stages, but it is not necessarily limited thereto and may be formed by being branched into multiple stages.

In this case, as illustrated inFIG.5, when a pressure of a Qsportion at the rear end of the ejector unit200increases, the flow rate of QE1branched with respect to QEtotalthrough which a constant flow rate is introduced through the main passage210decreases and the flow rate of QE2relatively increases.

Conversely, when the pressure of the Qsportion at the rear end of the ejector unit200is reduced, the flow rate of QE1branching with respect to QEtotalthat a constant flow rate is introduced through the main passage210increases, and the flow rate of QE2relatively decreases.

In this way, even if the exhaust gas pressure at the rear end of the ejector unit200is different, the flow rate of the primary dilution air2introduced into the exhaust gas introduction passage230through the first branch passage211and the second branch passage216that are branched is different (the total amount of the primary dilution air2is the same), the flow rate of the sucked Qsmay be kept constant. Therefore, in the present invention, even if the exhaust gas pressure of the rear end of the ejector unit200is different, since the amount of Qssucked is constant, the dilution ratio may be kept constant.

The primary dilution air2may be high-temperature air, and may be supplied at a temperature of 150° C. to 250° C.

The apparatus for diluting exhaust gas according to an exemplary embodiment of the present invention may further include a first adapter part500and a second adapter part550.

The first adapter part500may be coupled to a front end of the ejector unit200.

As illustrated inFIG.5, an extension diffuser501may be formed to penetrate through the first adapter part500in the axial direction. The extension diffuser501may be formed to have an inner diameter increasing toward the front direction and may be formed to be continuous with the diffuser236of the ejector unit200.

The first adapter part500may be provided with a second step groove502formed along an outer circumferential surface of a front end portion.

The second adapter part550may be coupled to a front end of the first adapter part500.

The second adapter part550may be provided with a passage hole551formed to penetrate through in the axial direction, and the passage hole551may be connected to the extension diffuser501of the first adapter part500.

The primary dilution air2introduced into the ejector unit200through the dilution air supply passages210,211, and216and the exhaust gas1sucked through the exhaust gas suction passage230are mixed to produce the primary dilution gas, and the produced primary dilution gas may move through the extension diffuser501and the passage hole551.

The second adapter part550may be provided with a third step groove552formed along the outer circumferential surface of the front end portion.

The dilution unit400may include a first passage part410into which the primary dilution gas is introduced through the first adapter part500and the second adapter part550and a second passage part420for guiding the supplied secondary dilution air3to the first passage part410to be mixed with the primary dilution gas. In the dilution unit400, the primary dilution gas and the secondary dilution air3may be mixed to produce the secondary dilution gas.

Specifically, the dilution unit400may be coupled to the front end of the first adapter part500and the second adapter part550. A rear end portion of the first passage part410may be coupled to the third step groove552of the second adapter part550. The first passage part410may be formed to be continuous with the passage hole551of the second adapter part550, and the primary dilution gas generated by being mixed in the diffuser236may move to the first passage part410.

A plurality of through holes411may be formed through the first passage part410.

The second passage part420may be formed to surround the first passage part410by a predetermined distance from the outside of the first passage part410. A rear end portion of the second passage part420may be coupled to the second step groove502of the first adapter part500.

A second inlet440through which the secondary dilution air3is introduced may be formed in the front end portion of the outer circumferential surface of the second passage part420. A second pipe441for guiding the secondary dilution air3from the outside may be connected to the second inlet440.

In addition, the dilution part400may be provided with a guide wall430. The guide wall430may be provided between the first passage part410and the second passage part420. In addition, the rear end portion of the guide wall430may be spaced apart from the front end portion of the first adapter part500. As a result, most of the space between the first passage part410and the second passage part420may be partitioned by the guide wall430, and the flow length of the secondary dilution air3introduced through the second inlet440may be long. That is, the secondary dilution air3introduced through the second inlet440may move in the rear direction in the space between the second passage part420and the guide wall430and may move to the space between the first passage part410and the guide wall430through the space between the guide wall430and the first adapter part500. Then, the secondary dilution air3moves to the inside of the first passage part410through the through hole411formed in the first passage part410and is mixed with the primary dilution gas to produce the secondary dilution gas.

Since the plurality of through holes411are formed in the first passage part410as a whole, the outer circumferential surface area of the first passage part410decreases. Accordingly, the number of particles that adheres to the inner circumferential surface of the first passage part410among the exhaust gas particles of the primary dilution gas may decrease, so the exhaust gas particle loss may decrease.

Furthermore, when the secondary dilution air3is introduced into the central direction of the first passage part410through the through hole411, it is possible to hinder the flow of particles toward the inner circumferential surface of the first passage part410and cause the exhaust gas particles adhering to the inner circumferential surface of the first passage part410to come off.

Accordingly, most of the particles in the exhaust gas moved in the first passage part410may be mixed with the secondary dilution air3, and the loss of particles while the exhaust gas turns into the secondary dilution gas may also be effectively reduced.

The apparatus for diluting exhaust gas according to the exemplary embodiment of the present invention may include a diffusion tube part570, a stopper580, and an exhaust pipe590.

The diffusion tube part570may be coupled to the front end of the dilution part400.

A rear end portion of the diffusion tube part570may be provided with a coupling groove572along the circumferential direction, so that the front end portion of the guide wall430is inserted and coupled thereto. In addition, the rear end portion of the diffusion tube part570may be inserted and coupled to the inside of the second passage part420.

The diffusion tube part570may be provided with an additional diffuser571that is formed to penetrate through in the axial direction. The additional diffuser571may be formed to have an inner diameter increasing toward the front, and the secondary dilution gas generated in the dilution unit400may move to the additional diffuser571.

The stopper580may be coupled to the front end portion of the diffusion tube part570to seal the front end portion of the diffusion tube part570.

A plurality of discharge pipes590may be coupled to the stopper580. A connection hole581may be formed to penetrate through the stopper580so that the stopper580is coupled to the discharge pipe590, and the secondary dilution gas of the additional diffuser571may be moved to the discharge pipe590through the connection hole581. A particle counter (not illustrated) may be connected to at least one of the discharge pipes590, and the secondary dilution gas may move to the particle counter through the discharge pipe590.

According to this exemplary embodiment, the introduced exhaust gas1is mixed with the primary dilution air2in the ejector unit200to be primarily diluted and is mixed with the secondary dilution air3in the dilution unit400to be secondarily diluted, so the dilution rate may increase.

As described above, the primary dilution air2supplied to the ejector unit200may be a high temperature air of 150° C. to 250° C. Therefore, the primary dilution gas generated through the ejector unit200may be generated by a high-temperature dilution method. The secondary dilution air3supplied to the dilution unit400may be room-temperature air, and may be supplied at a temperature of 10° C. to 30° C. Accordingly, the secondary dilution gas generated by the dilution unit400may be generated by a dilution method at room temperature.

FIG.6is a graph for describing an effect according to dilution temperature in the apparatus for diluting exhaust gas according to an exemplary embodiment of the present invention.

Referring toFIG.6, the exhaust gas introduced into the ejector unit200is in a high temperature state (P0). When the primary dilution air mixed with the exhaust gas in the high temperature state is room-temperature air, that is, when the high-temperature exhaust gas is diluted at room temperature, all moisture in the exhaust gas may be converted into droplets. Accordingly, the primary dilution gas in the first state P1generated by the diffuser236may contain a large amount of droplets. When the primary dilution gas containing a large amount of droplets is mixed with the room-temperature secondary dilution air in the dilution unit400to produce the secondary dilution gas in the second state (P2), a large amount of droplets is continuously contained in the secondary dilution gas. Since these droplets may be treated as particles during measurement in the particle counter (not illustrated), it may cause a decrease in measurement accuracy.

However, according to the present invention, the primary dilution gas generated in the diffuser236may be in a third state P3by mixing the exhaust gas in the high temperature state (P0) with the high-temperature primary dilution air2, that is, by diluting the high-temperature exhaust gas at a high temperature, and moisture in the exhaust gas may be prevented from becoming droplets. In addition, since the primary dilution gas is mixed with the room-temperature secondary dilution air3in the dilution unit400to form the secondary dilution gas in the second state P2, the secondary dilution gas does not contain droplets or may contain a minimal amount of droplets, so the measurement accuracy of the particles may be improved.

The preheating unit600may be provided in the rear end portion of the ejector unit200and may pre-heat the exhaust gas1introduced into the ejector unit200. The preheating unit600may preheat the exhaust gas1to a temperature of 190° C. to 210° C. When the exhaust gas1is preheated and moved to the ejector unit200, it can be mixed with the above-mentioned primary dilution air2to be more effectively diluted at a high temperature.

As illustrated inFIG.7, the cleaning fluid supplier700may include a compressor710, a drier720, a filter unit730, and a joint passage part740.

The compressor710may compress and inject a cleaning fluid PA. The room-temperature air may be used as the cleaning fluid PA but is not necessarily limited thereto.

The drier720may be provided at the front end of the compressor710and may dry the cleaning fluid PA.

The filter unit730may be provided at the front end of the drier720and may remove foreign substances contained in the cleaning fluid PA.

Accordingly, the cleaning fluid PA discharged from the filter unit730may be in a state not to contain moisture and foreign substances.

The joint passage part740may be provided between the ejector unit200and the preheating unit600. The joint passage part740may guide a portion of the cleaning fluid PA moving through the filter unit730to the ejector unit200and guide the rest of the cleaning fluid PA to the preheating unit600. To this end, the joint passage part740may include an introduction passage741extending in the radial direction of the joint passage part740and connected to the filter part730to introduce the cleaning fluid PA moving from the filter part730, a first guide passage742connected to the introduction passage741and extending in the direction of the ejector unit200, and a second guide passage743connected to the introduction passage741and extending in the direction of the preheating part600. The first guide passage742and the second guide passage743may be formed to be symmetrical to each other with respect to the introduction passage741and may be formed to have the same diameter. The cleaning fluid PA introduced into the introduction passage741may be supplied to the first guide passage742and the second guide passage743, respectively, at the same flow rate. The joint passage part740may be provided with a splitting protrusion744so that the cleaning fluid PA introduced into the introduction passage741may be bisected and supplied to the first guide passage742and the second guide passage743, respectively, at the same flow rate. The splitting protrusion744is formed to protrude in the center so as to face the introduction passage741at the point where it is bisected into the first guide passage742and the second guide passage743, thereby bisecting the introduction passage741.

The cleaning fluid PA moving to the first guide passage742cleans the inside of each part while moving through the ejector unit200, the dilution part400, the diffusion tube part570, and the discharge pipe590.

In addition, the cleaning fluid PA moving to the second guide passage743may clean the inside of the preheating unit600while moving through the preheating unit600.

As illustrated inFIGS.1,2and8, the apparatus for diluting exhaust gas may include a measuring unit800that is coupled to the front end of the diluting unit400, and measures particle information of the secondary diluting gas.

The measuring unit800may be configured to include an injector810, a light source820, a light receiving unit830, and a calculator840.

The secondary dilution gas may move to the injector810through a flow passage591connected to the discharge pipe590. Then, the injector810may sequentially inject particles P included in the secondary dilution gas one by one.

The light source820may irradiate the light821in a direction crossing the injection path of the particles P injected from the injector810. When the light821crossing the injection path of the particle P collides with the particle P on the injection path, scattering may occur.

The light receiving unit830is provided on one side of the injection path and may receive the light822scattered by the particles P injected from the injector810after being irradiated from the light source820. When the size of the particles P injected from the injector810is large, the scattered light822may increase, and conversely, when the size of the particles P is small, the scattered light822may decrease.

The calculator840may calculate size information of particles included in the secondary dilution gas based on the light information generated by the light receiving unit830. The particle size information may be calculated for particles acquired during a preset measurement time. The size information of particles may be calculated for particles acquired during a preset measurement time.

The size information of particles calculated by the calculator840may be calculated as, for example, the concentration of PM10 (Particulate Matter with a diameter less than 10 μm), which is usually referred to as fine dust with a particle size of 10 μm or less, or the concentration of PM2.5, which is usually referred to as ultra fine dust with a particle size of 2.5 μm or less.

The measuring unit800is not limited to the above-described configuration and may be formed in other known configurations for measuring the concentration of particles.

The closer the cleaning fluid supplier700is to the front end of the apparatus for diluting exhaust gas, the closer the distance between the supplied cleaning fluid and the measuring unit800is. Then, foreign substances inside the apparatus for diluting exhaust gas move to the measuring unit800by the cleaning fluid, and disturbance of the measuring unit800may occur, so the measurement accuracy may decrease. However, in the present invention, the cleaning fluid supplier700is connected to the relatively rear part of the apparatus for diluting exhaust gas, so that the distance between the supplied cleaning fluid and the measuring unit800may be sufficiently secured, thereby preventing the above-mentioned problems from occurring.

The scope of the present invention is not limited to the abovementioned exemplary embodiment but may be implemented in various forms that fall within the claims. The present invention may be variously modified by those skilled in the art to which the present invention pertains without departing from the scope of the present invention as defined by the claims. In addition, these modifications are to fall within the scope of the appended claims.

<Description of symbols>1: Exhaust gas2: Primary dilution air3: Secondary dilution air200: Ejector unit210: Main passage211: First branch passage212: End portion of first branch passage216: Second branch passage217: End portion of second branch passage221: First pipe230: Exhaust gas suction passage231: Space part232: First suction unit233: First accelerator234: Second suction unit235: Second accelerator236: Diffuser400: Dilution unit410: First passage part411: Through hole420: Second passage part430: Guide wall440: Second inlet441: Second pipe500: First adapter part501: Extension diffuser502: Second step groove550: Second adapter part551: Passage hole552: Third step groove570: Diffusion tube part571: Additional diffuser572: Coupling groove580: Stopper581: Connection hole590: Discharge pipe591: Flow passage600: Preheating unit700: Cleaning fluid supplier710: Compressor720: Drier730: Filter unit740: Joint passage part741 Introduction passage742: First guide passage743: Second guide passage744: Splitting protrusion800: Measuring unit810: Injector820: Light source830: Light receiving unit840: Calculator900: Stagnant air forming unit910: Diffuser unit915: Introduction hole920: Air retention part925: Outlet hole940: Sampling outlet part