− Using a premixed flat flame aerosol reactor, the experimental study on the morphological evolut... more − Using a premixed flat flame aerosol reactor, the experimental study on the morphological evolution of the aggregates was done. With the objectives to understand the morphological process of SiO 2 and TiO2 particle that matches to the cases of the reaction-limited aggregation process and the diffusion-limited aggregation process respectively, the difference in chemical reaction rate of SiCl 4 and TiCl 4 was utilized under given flame temperatures. To evaluate the morphological evolution of the aggregates, the light scattering measurement and electron microscopy coupled with thermophoretic sampling method were used. In the case of SiCl 4 oxidation that produces SiO 2 particles, the microscopic observation obtained with respect to the axial position in the reactor showed that the diffusion-limited aggregation was the dominant mechanism in the aggregation process because that the very low reaction rates was maintained excepted the earlier reaction stage in the given reactor temperatur...
UV-TiO2 광촉매를 이용한 공기 정화 시스템에 운전조건에 대한 연구가 수행되었다. 이 연구에서 시스템의 운영 조건이 바뀜에 따른 오염물질 제거 특성을 관찰하기 위해 덕트 ... more UV-TiO2 광촉매를 이용한 공기 정화 시스템에 운전조건에 대한 연구가 수행되었다. 이 연구에서 시스템의 운영 조건이 바뀜에 따른 오염물질 제거 특성을 관찰하기 위해 덕트 형태의 반응기를 제작하고, 스테인레스 격자망에 TiO2를 코팅하였다. 또한 benzene을 이용하여 UV/TiO2 공정으로 유입농도를 변화시키고, 반응기로 들어오는 유량을 조절하여 TiO2를 코팅한 스테인레스 격자망을 부착한 평판에서의 유속을 변화시켰으며, 코팅한 TiO2 광촉매량을 변화시키고, 일정한 양의 TiO2 광촉매를 코팅한 면적을 변화시켰으며, UV light intensity를 변화시켜 그에 따른 영향을 관찰하였다. 모든 실험에서의 상대습도는 55%, 반응기 온도는 45℃를 유지하였다. 실험의 결과를 살펴보면, benzene의 유입농도가 증가할수록 제거효율이 감소하였고, 유속이 느려질수록, 즉 농도 경계층 두께(concentration boundary layer thickness)가 증가할수록, 코팅한 광촉매량, 광촉매를 코팅한 면적, 조사한 UV 램프의 intensity가 증가할수록 benzene 제거효율이 증가하였다. 본 연구 자료를 바탕으로 실내 공기 중 저농도의 VOCs를 대상으로 공기 정화 시스템을 설계할 경우 유용하게 적용할 수 있는 자료를 제시할 수 있다고 판단된다.
Journal of Korean Society of Environmental Engineers, 2008
: A study on the operational variables of the UV-TiO 2 based photocatalytic air cleaning system w... more : A study on the operational variables of the UV-TiO 2 based photocatalytic air cleaning system was tried. In this study, toexamine effects as various air cleaning system conditions, a duct-type reactor was made, and TiO 2 was immobilized on a stainless mesh.Benzene was chosen as a target compound. Removal experiments for benzene were done under different initial benzene concentration, air velocity, TiO 2 loading, area coated TiO 2 as the same TiO 2 loading, and UV light intensity conditions. During the experiments, rela-tive humidity was 55%, and reactor temperature was 45. As a result, the photocatalytic degradation of benzene decreased as the inletconcentration increased. But the photocatalytic degradation increased as the concentration boundary layer thickness, amount of TiO 2 , areacoated TiO 2 as the same amount of TiO 2 , and UV light intensity increased. Based on results of current study, they can be applied to thedesign of air cleaning system over low level VOCs in the ind...
Transactions of the Korean Society of Mechanical Engineers B, 2003
Effects of the electric conductivity of particles were studied for the aggregation process of cha... more Effects of the electric conductivity of particles were studied for the aggregation process of charged particles with a Brownian dynamic simulation in the free molecular regime. A periodic boundary condition was used for the calculation of the aggregation process in each cell with 500 primary particles of 16 nm in diameter. We considered two extreme cases, a perfect conductor and a perfect nonconductor. The electrostatic force on a particle in the simulation cell was considered as a sum of electrostatic forces from other particles in the original cell and its replicate cells. We assumed that aggregates were only charged with pre-charged primary particles. The morphological shape of aggregates was described in terms of the fractal dimension. The fractal dimension for the uncharged aggregate was D
Using the CFD method, the pressure drop in 6 cyclone dust collectors of different shape were calc... more Using the CFD method, the pressure drop in 6 cyclone dust collectors of different shape were calculated. And the results were compared with results of the conventional theories. Equations of Shepherd and Lapple (1939, 1940), First (1950), Alexander (1949), Stairmand (1949), Barth (1956) were used in the theoretical calculation. In CFD calculations, we used standard k-epsilon model for analysis of turbulent flow, fluid is 25 ℃ air, the velocity at inlet is 10 m/s and the temperature is 25 ℃. In CFD analysis results, the pressure distributions along the flow showed similar patterns in different cyclone shapes. But the pressure drop distributions estimated on the conventional theories had big difference in different cyclone shapes. Only First's theory and CFD analysis showed similar results.
The photocatalytic degradation of gaseous formaldehydesa major cause of sick building syndromeswa... more The photocatalytic degradation of gaseous formaldehydesa major cause of sick building syndromeswas studied using a TiO 2 thin film. TiO 2 thin films have many unique photoinduced properties, for example, self-cleaning, antifouling, and anti-bacterial functions. UV illumination of the TiO 2 thin film placed in a gaseous formaldehyde/air environment resulted in the total mineralization of formaldehyde to CO 2 and H 2 O. We invoked a Langmuir-Hinshelwood kinetic model to analyze the dependence of reaction rates on the concentration of formaldehyde. In addition, the overall decomposition rate constant for formaldehyde was comparable to that of acetaldehyde (a standard test reactant) for initial concentrations of up to 1000 ppmv. However, the apparent adsorption constant K app of formaldehyde onto TiO 2 was ca. 2.5 times larger than that of acetaldehyde. Thus in the low concentration regime, the reactivity of formaldehyde appeared to be greater than that of acetaldehyde. In like manner, a dark adsorption experiment also showed the high adsorption capacity of TiO 2 for formaldehyde. Therefore, we conclude that TiO 2 serves as both a good adsorbent and a photocatalyst for the elimination of gaseous formaldehyde.
Using a premixed flat flame, the aggregation process of thermally stable particles was studied. B... more Using a premixed flat flame, the aggregation process of thermally stable particles was studied. Based on the theoretical descriptions of the reaction limited aggregation process (RLAP) and the diffusion limited aggregation process (DLAP), the entire aggregation process was explained by a combination of the RLAP and the DLAP. Experiments were done to test the possibility of this explanation for the dynamic aggregation processes in terms of the parameters that are used in a normal chemical conversion process. By defining the primary particle as the basic unit of the aggregates, the aggregation process was divided into the early stage--when the primary particles are formed--and the stage of aggregation thereafter. Changing the combustion equivalence ratio of the premixed flat flame from 0.7 to 0.98 controlled the sizes of the primary particles. The deficiency of the oxygen in the combustion process controlled the final size of the primary particles in the aggregate. The morphological evolution of particles was well defined due to the stable condition in the flow. Titania and silica that were formed in the flame by the oxidation of TiCl 4 and SiCl 4 were used as the simulation materials of the aggregation process. Depending on the residence time and temperature history in the oxidation process, the aggregates were formed in various fractal dimensions. The thermophoretic sampling and image analysis techniques were used to evaluate the aggregation in the flame region. The coalescence effect on the particle morphology was estimated by using the tubular aerosol reactor.
Laboratory experiments were carried out to study the removal of SO 2 by the particle conversion p... more Laboratory experiments were carried out to study the removal of SO 2 by the particle conversion process in a simulated ue gas condition. For the conversion of SO to particulate forms, NH was injected to the reaction zone. For 2 3
Various technical methods are applied for removing water from the water-retaining media, and the ... more Various technical methods are applied for removing water from the water-retaining media, and the energy efficiency is the main concern in those methods. The electroosmotic process is studied as an efficient way for dewatering. An experimental electroosmotic reactor is designed and used for evaluating the effects of operational variables. The operational variables such as the electrical fields and the structure of water-retaining medias were studied. Three different shapes of polarized electric fields in ranges of 0-100 V/cm and 0-10 kHz are used as the source of electric voltage. The effect of electroosmotic process with respect to the structural variation is estimated by filling the electroosmotic reactor with the glass beads in 0.18 mm, 0.35 mm and 1.2 mm in diameters. 6% of water removal is obtained in the simulating electroosmotic reactor of glass beads. The estimated energy consumption in the simulating electroosmotic was 330~490 cal/g-water.
Journal of Korean Society of Environmental Engineers, 2011
A package type of SCR (selective catalytic reduction) system that was proposed for removing the N... more A package type of SCR (selective catalytic reduction) system that was proposed for removing the NOx found in flue gas from the small scale of air pollution sources was evaluated. The efficiency of the SCR system is determined by the proper utilization of catalytic media installed inside of the system, and the proper distribution of flow velocity and NH3 concentration in the flue gas is a crucial factor for using the catalytic media. In this study, the distributions of NH3 concentration were estimated under the various arrays and shapes of AIG at the given gas flow condition. The value of RMS (%) in NH3 concentration is 95.3% at co-current flow (at 0°) injection but it is 90.1% at the condition of counter-current flow (at 120°) condition, which implies the counter-current injection is more favorable. By rearranging the NH3 injection flow rates based on the distribution of velocity and NH3 distribution in basic calculation, the value of RMS (%) in NH3 concentration was reduced to 62.8%. The enhanced effect of NH3 mixing by the combined effect of arrays and shapes are complied in the study.
The performance of the ammonia injection gun (AIG) used for maximizing the utilization of reducin... more The performance of the ammonia injection gun (AIG) used for maximizing the utilization of reducing agent in the selective catalytic reduction (SCR) system is decided by several parameters such as the pattern of flow distribution, geometry of the air distribution manifold (ADM) and the array and geometry of nozzles. In the study, the uniformity of jet flows from the nozzles in AIG was analyzed statistically by using the computational fluid dynamics (CFD) method to evaluate the role of design parameters on the performance of the SCR system. The uniformity of jet flows from the nozzles is being deteriorated with increasing the supplying flow rate to the AIG. Distribution rates to each branch pipe become lower with decreasing distance to the header, and flow rates from nozzle are also reduced with decreasing distance to the header. The uniformity of jet flows from nozzles becomes stable significantly when the ratio of summative area of nozzles to each sectional area of the branch pipe is below 0.5.
The present study has been carried out to diagnose the temperature safety of a boiler desuperheat... more The present study has been carried out to diagnose the temperature safety of a boiler desuperheater which decreases abnormally higher temperature of superheated steam in a reheater of a power plant. The liquid water in the desuperheater stays in a closed space. It becomes heated by the high temperature superheated steam and boiling could occur. Boiling might increase internal pressure and it could destroy the desuperheater if the internal pressure exceeds the allowable pressure of the desuperheater. The present study modeled reasonably the desuperheater and four cases of heat transfer analysis are executed with the consideration of insulator and natural convective fluid flow of the inside cooling water. For the case excluded the natural convective fluid flow, the temperature exceeds the allowable temperature and pressure. On the other hand, for the real case included natural convective fluid flow and insulator, the active heat transfer from higher temperature region to lower temperature region occurs and it makes the temperature in the cooling water below the allowable temperature and pressure. From this fact, it could be thought that the desuperheater in the reheater is safe from destroy or back flow.
Numerical analysis was done to evaluate the fluid distribution inside of the mixing quencher to i... more Numerical analysis was done to evaluate the fluid distribution inside of the mixing quencher to increase the reaction efficiency of the aqueous hydrogen peroxide solution in the scrubbing column which is used for simultaneous desulfurization and denitrification. Effective injection of the aqueous hydrogen peroxide (H2O2) solution in the mixing quencher has major effects for improving the reaction efficiency in the scrubbing column by enhancing the mixing of the aqueous H2O2 solution with the exhaust gas. The current study is to optimize the array of nozzles and the spray angles of the aqueous H2O2 solution in the mixing quencher by using the computational method. Main concerns of the analysis are how to enhance the uniformity of the H2O2 concentration distribution in the internal flow. Numerical analysis was done to check the distribution of the internal flow in the mixing quencher in terms of RMS values of the H2O2 concentration at the end of quencher. The concentration distribution of H2O2 at the end of is evaluated with respect to the different array of the nozzle pipes and the nozzle tip angles, and we also analyzed the turbulence formation and fluid mixing in the zone. The effect of the spray angle was evaluated with respect to the mixing efficiency in different flow directions. The optimized mixing quencher had the nozzle array at location of 0.3 m from the inlet duct surface and the spray angle is 15° with the co-current flow. The RMS value of the H2O2 concentration at the end of the mixing quencher was 12.4%.
− Using a premixed flat flame aerosol reactor, the experimental study on the morphological evolut... more − Using a premixed flat flame aerosol reactor, the experimental study on the morphological evolution of the aggregates was done. With the objectives to understand the morphological process of SiO 2 and TiO2 particle that matches to the cases of the reaction-limited aggregation process and the diffusion-limited aggregation process respectively, the difference in chemical reaction rate of SiCl 4 and TiCl 4 was utilized under given flame temperatures. To evaluate the morphological evolution of the aggregates, the light scattering measurement and electron microscopy coupled with thermophoretic sampling method were used. In the case of SiCl 4 oxidation that produces SiO 2 particles, the microscopic observation obtained with respect to the axial position in the reactor showed that the diffusion-limited aggregation was the dominant mechanism in the aggregation process because that the very low reaction rates was maintained excepted the earlier reaction stage in the given reactor temperatur...
UV-TiO2 광촉매를 이용한 공기 정화 시스템에 운전조건에 대한 연구가 수행되었다. 이 연구에서 시스템의 운영 조건이 바뀜에 따른 오염물질 제거 특성을 관찰하기 위해 덕트 ... more UV-TiO2 광촉매를 이용한 공기 정화 시스템에 운전조건에 대한 연구가 수행되었다. 이 연구에서 시스템의 운영 조건이 바뀜에 따른 오염물질 제거 특성을 관찰하기 위해 덕트 형태의 반응기를 제작하고, 스테인레스 격자망에 TiO2를 코팅하였다. 또한 benzene을 이용하여 UV/TiO2 공정으로 유입농도를 변화시키고, 반응기로 들어오는 유량을 조절하여 TiO2를 코팅한 스테인레스 격자망을 부착한 평판에서의 유속을 변화시켰으며, 코팅한 TiO2 광촉매량을 변화시키고, 일정한 양의 TiO2 광촉매를 코팅한 면적을 변화시켰으며, UV light intensity를 변화시켜 그에 따른 영향을 관찰하였다. 모든 실험에서의 상대습도는 55%, 반응기 온도는 45℃를 유지하였다. 실험의 결과를 살펴보면, benzene의 유입농도가 증가할수록 제거효율이 감소하였고, 유속이 느려질수록, 즉 농도 경계층 두께(concentration boundary layer thickness)가 증가할수록, 코팅한 광촉매량, 광촉매를 코팅한 면적, 조사한 UV 램프의 intensity가 증가할수록 benzene 제거효율이 증가하였다. 본 연구 자료를 바탕으로 실내 공기 중 저농도의 VOCs를 대상으로 공기 정화 시스템을 설계할 경우 유용하게 적용할 수 있는 자료를 제시할 수 있다고 판단된다.
Journal of Korean Society of Environmental Engineers, 2008
: A study on the operational variables of the UV-TiO 2 based photocatalytic air cleaning system w... more : A study on the operational variables of the UV-TiO 2 based photocatalytic air cleaning system was tried. In this study, toexamine effects as various air cleaning system conditions, a duct-type reactor was made, and TiO 2 was immobilized on a stainless mesh.Benzene was chosen as a target compound. Removal experiments for benzene were done under different initial benzene concentration, air velocity, TiO 2 loading, area coated TiO 2 as the same TiO 2 loading, and UV light intensity conditions. During the experiments, rela-tive humidity was 55%, and reactor temperature was 45. As a result, the photocatalytic degradation of benzene decreased as the inletconcentration increased. But the photocatalytic degradation increased as the concentration boundary layer thickness, amount of TiO 2 , areacoated TiO 2 as the same amount of TiO 2 , and UV light intensity increased. Based on results of current study, they can be applied to thedesign of air cleaning system over low level VOCs in the ind...
Transactions of the Korean Society of Mechanical Engineers B, 2003
Effects of the electric conductivity of particles were studied for the aggregation process of cha... more Effects of the electric conductivity of particles were studied for the aggregation process of charged particles with a Brownian dynamic simulation in the free molecular regime. A periodic boundary condition was used for the calculation of the aggregation process in each cell with 500 primary particles of 16 nm in diameter. We considered two extreme cases, a perfect conductor and a perfect nonconductor. The electrostatic force on a particle in the simulation cell was considered as a sum of electrostatic forces from other particles in the original cell and its replicate cells. We assumed that aggregates were only charged with pre-charged primary particles. The morphological shape of aggregates was described in terms of the fractal dimension. The fractal dimension for the uncharged aggregate was D
Using the CFD method, the pressure drop in 6 cyclone dust collectors of different shape were calc... more Using the CFD method, the pressure drop in 6 cyclone dust collectors of different shape were calculated. And the results were compared with results of the conventional theories. Equations of Shepherd and Lapple (1939, 1940), First (1950), Alexander (1949), Stairmand (1949), Barth (1956) were used in the theoretical calculation. In CFD calculations, we used standard k-epsilon model for analysis of turbulent flow, fluid is 25 ℃ air, the velocity at inlet is 10 m/s and the temperature is 25 ℃. In CFD analysis results, the pressure distributions along the flow showed similar patterns in different cyclone shapes. But the pressure drop distributions estimated on the conventional theories had big difference in different cyclone shapes. Only First's theory and CFD analysis showed similar results.
The photocatalytic degradation of gaseous formaldehydesa major cause of sick building syndromeswa... more The photocatalytic degradation of gaseous formaldehydesa major cause of sick building syndromeswas studied using a TiO 2 thin film. TiO 2 thin films have many unique photoinduced properties, for example, self-cleaning, antifouling, and anti-bacterial functions. UV illumination of the TiO 2 thin film placed in a gaseous formaldehyde/air environment resulted in the total mineralization of formaldehyde to CO 2 and H 2 O. We invoked a Langmuir-Hinshelwood kinetic model to analyze the dependence of reaction rates on the concentration of formaldehyde. In addition, the overall decomposition rate constant for formaldehyde was comparable to that of acetaldehyde (a standard test reactant) for initial concentrations of up to 1000 ppmv. However, the apparent adsorption constant K app of formaldehyde onto TiO 2 was ca. 2.5 times larger than that of acetaldehyde. Thus in the low concentration regime, the reactivity of formaldehyde appeared to be greater than that of acetaldehyde. In like manner, a dark adsorption experiment also showed the high adsorption capacity of TiO 2 for formaldehyde. Therefore, we conclude that TiO 2 serves as both a good adsorbent and a photocatalyst for the elimination of gaseous formaldehyde.
Using a premixed flat flame, the aggregation process of thermally stable particles was studied. B... more Using a premixed flat flame, the aggregation process of thermally stable particles was studied. Based on the theoretical descriptions of the reaction limited aggregation process (RLAP) and the diffusion limited aggregation process (DLAP), the entire aggregation process was explained by a combination of the RLAP and the DLAP. Experiments were done to test the possibility of this explanation for the dynamic aggregation processes in terms of the parameters that are used in a normal chemical conversion process. By defining the primary particle as the basic unit of the aggregates, the aggregation process was divided into the early stage--when the primary particles are formed--and the stage of aggregation thereafter. Changing the combustion equivalence ratio of the premixed flat flame from 0.7 to 0.98 controlled the sizes of the primary particles. The deficiency of the oxygen in the combustion process controlled the final size of the primary particles in the aggregate. The morphological evolution of particles was well defined due to the stable condition in the flow. Titania and silica that were formed in the flame by the oxidation of TiCl 4 and SiCl 4 were used as the simulation materials of the aggregation process. Depending on the residence time and temperature history in the oxidation process, the aggregates were formed in various fractal dimensions. The thermophoretic sampling and image analysis techniques were used to evaluate the aggregation in the flame region. The coalescence effect on the particle morphology was estimated by using the tubular aerosol reactor.
Laboratory experiments were carried out to study the removal of SO 2 by the particle conversion p... more Laboratory experiments were carried out to study the removal of SO 2 by the particle conversion process in a simulated ue gas condition. For the conversion of SO to particulate forms, NH was injected to the reaction zone. For 2 3
Various technical methods are applied for removing water from the water-retaining media, and the ... more Various technical methods are applied for removing water from the water-retaining media, and the energy efficiency is the main concern in those methods. The electroosmotic process is studied as an efficient way for dewatering. An experimental electroosmotic reactor is designed and used for evaluating the effects of operational variables. The operational variables such as the electrical fields and the structure of water-retaining medias were studied. Three different shapes of polarized electric fields in ranges of 0-100 V/cm and 0-10 kHz are used as the source of electric voltage. The effect of electroosmotic process with respect to the structural variation is estimated by filling the electroosmotic reactor with the glass beads in 0.18 mm, 0.35 mm and 1.2 mm in diameters. 6% of water removal is obtained in the simulating electroosmotic reactor of glass beads. The estimated energy consumption in the simulating electroosmotic was 330~490 cal/g-water.
Journal of Korean Society of Environmental Engineers, 2011
A package type of SCR (selective catalytic reduction) system that was proposed for removing the N... more A package type of SCR (selective catalytic reduction) system that was proposed for removing the NOx found in flue gas from the small scale of air pollution sources was evaluated. The efficiency of the SCR system is determined by the proper utilization of catalytic media installed inside of the system, and the proper distribution of flow velocity and NH3 concentration in the flue gas is a crucial factor for using the catalytic media. In this study, the distributions of NH3 concentration were estimated under the various arrays and shapes of AIG at the given gas flow condition. The value of RMS (%) in NH3 concentration is 95.3% at co-current flow (at 0°) injection but it is 90.1% at the condition of counter-current flow (at 120°) condition, which implies the counter-current injection is more favorable. By rearranging the NH3 injection flow rates based on the distribution of velocity and NH3 distribution in basic calculation, the value of RMS (%) in NH3 concentration was reduced to 62.8%. The enhanced effect of NH3 mixing by the combined effect of arrays and shapes are complied in the study.
The performance of the ammonia injection gun (AIG) used for maximizing the utilization of reducin... more The performance of the ammonia injection gun (AIG) used for maximizing the utilization of reducing agent in the selective catalytic reduction (SCR) system is decided by several parameters such as the pattern of flow distribution, geometry of the air distribution manifold (ADM) and the array and geometry of nozzles. In the study, the uniformity of jet flows from the nozzles in AIG was analyzed statistically by using the computational fluid dynamics (CFD) method to evaluate the role of design parameters on the performance of the SCR system. The uniformity of jet flows from the nozzles is being deteriorated with increasing the supplying flow rate to the AIG. Distribution rates to each branch pipe become lower with decreasing distance to the header, and flow rates from nozzle are also reduced with decreasing distance to the header. The uniformity of jet flows from nozzles becomes stable significantly when the ratio of summative area of nozzles to each sectional area of the branch pipe is below 0.5.
The present study has been carried out to diagnose the temperature safety of a boiler desuperheat... more The present study has been carried out to diagnose the temperature safety of a boiler desuperheater which decreases abnormally higher temperature of superheated steam in a reheater of a power plant. The liquid water in the desuperheater stays in a closed space. It becomes heated by the high temperature superheated steam and boiling could occur. Boiling might increase internal pressure and it could destroy the desuperheater if the internal pressure exceeds the allowable pressure of the desuperheater. The present study modeled reasonably the desuperheater and four cases of heat transfer analysis are executed with the consideration of insulator and natural convective fluid flow of the inside cooling water. For the case excluded the natural convective fluid flow, the temperature exceeds the allowable temperature and pressure. On the other hand, for the real case included natural convective fluid flow and insulator, the active heat transfer from higher temperature region to lower temperature region occurs and it makes the temperature in the cooling water below the allowable temperature and pressure. From this fact, it could be thought that the desuperheater in the reheater is safe from destroy or back flow.
Numerical analysis was done to evaluate the fluid distribution inside of the mixing quencher to i... more Numerical analysis was done to evaluate the fluid distribution inside of the mixing quencher to increase the reaction efficiency of the aqueous hydrogen peroxide solution in the scrubbing column which is used for simultaneous desulfurization and denitrification. Effective injection of the aqueous hydrogen peroxide (H2O2) solution in the mixing quencher has major effects for improving the reaction efficiency in the scrubbing column by enhancing the mixing of the aqueous H2O2 solution with the exhaust gas. The current study is to optimize the array of nozzles and the spray angles of the aqueous H2O2 solution in the mixing quencher by using the computational method. Main concerns of the analysis are how to enhance the uniformity of the H2O2 concentration distribution in the internal flow. Numerical analysis was done to check the distribution of the internal flow in the mixing quencher in terms of RMS values of the H2O2 concentration at the end of quencher. The concentration distribution of H2O2 at the end of is evaluated with respect to the different array of the nozzle pipes and the nozzle tip angles, and we also analyzed the turbulence formation and fluid mixing in the zone. The effect of the spray angle was evaluated with respect to the mixing efficiency in different flow directions. The optimized mixing quencher had the nozzle array at location of 0.3 m from the inlet duct surface and the spray angle is 15° with the co-current flow. The RMS value of the H2O2 concentration at the end of the mixing quencher was 12.4%.
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