• Title, Summary, Keyword: Reformer

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Operation characteristics of partial oxidation reformer for transportation fuels (수송 연료용 부분산화 개질기의 운전특성)

  • Lee, Sangho;Bae, Joongmyeon
    • 한국신재생에너지학회:학술대회논문집
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    • pp.159.1-159.1
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    • 2011
  • Partial oxidation reformer was fabricated and operated using commercial transportation fuels. Fuel injector and heating coil were used for fuel atomization and startup, respectively. The reformer was designed to produce syngas for $150{\sim}200W_e$ class solid oxide fuel cell. The reformer was operated in the $O_2$/C range between 0.6 and 0.8 while the capacity was fixed at $150W_e$. The temperature range in catalyst bed was between $500^{\circ}C$ and $900^{\circ}C$. Only 83% fuel was converted to $H_2$, CO, $CO_2$ and $CH_4$ at the operating conditions. The lowest temperature increase to $700^{\circ}C$ when the reformer was operated at $200W_e$, Although the temperature profiles was improved, fuel conversion was 88%. On the other hand, fuel was completely converted when micro-reactor operated at the same condition. This difference maybe due to aromatic compounds formation at homogeneous region. In addition, a significant amount of coke deposition was observed at vent line. Homogeneous reaction depends on the degree of mixing. For this purpose, two fluid nozzle and Ultra sonic injector were compared to investigate the effect of atomization. Sauter mean diameter(SMD) of Ultra sonic injector was lower than two-fluid nozzle at test condition. However, conversion efficiency and fuel conversion were not improved by using two-fluid nozzle. these results imply that the temperature of homogeneous reaction region should be controlled to prevent coke formation.

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Effect of Tip Size and Aspect Ratio on Reforming Performance in a Methane Reformer for Polymer Electrolyte Membrane Fuel Cell (PEMFC) (고분자 전해질 막 연료전지를 위한 메탄 개질기에서 형상 변화가 개질 성능에 미치는 영향에 대한 연구)

  • Seo, Dong-Kyun;Noh, In-Kyu;Hwang, Jung-Ho;Choi, Jong-Kyun;Shin, Dong-Hoon;Kim, Hyung-Sik
    • Transactions of the Korean hydrogen and new energy society
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    • v.21 no.5
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    • pp.364-374
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    • 2010
  • Design of a reformer consisting of combustion chamber and reforming chamber was investigated for a 1 kW and a 5 kW polymer electrolyte membrane fuel cell (PEMFC), respectively, using the computational fluid dynamics (CFD). First, the 1kW reformer was considered to obtain the reliability of the numerical study. It was modeled, calculated and compared with experimental data. Second, the 5kW reformer was considered for a geometric study. Three tip sizes (35, 40, and 45 mm) and five aspect ratios was selected. It was found that the optimum was at tip sizes of 40 and 45 mm, at aspect ratios of -10% and -20% of the standard length.

The Efficiency Prediction for Plate Type Steam Reformer with Shape Change of Combustion Chamber (평판형 STR의 연소공간 형상변화에 따른 성능 예측)

  • Kim, Hun-Ju;Lee, Ji-Hong;Lee, Myeong-Yong;Lee, Sang-Seok;Lee, Do-Hyung
    • Transactions of the Korean hydrogen and new energy society
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    • v.21 no.4
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    • pp.286-294
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    • 2010
  • According to the propagation of fuel cell system, the importance of that system efficiency is being magnified. Thus, the efficiency improvement of reformer which is the important part of fuel cell system will be required. In structural aspect, the reformer is classified into cylindrical and plate type. Plate type reformer features better maintenance and space efficiency compared with cylindrical type. In this study, we changed the shape of combustion chamber to improve the reforming efficiency. And then we performed the CFD simulation to predict the spacial distribution of temperature. Analysis cased contains with baffles, fins, baffles and fins, and without those. In case of only with-baffle, temperature distributions were uneven because the high temperature stream was concentrated near the baffle end. In case of with-fin, the temperature distributions were relatively even than other cases.

Feasibility Study of Low NOx Combustion based on FGR using Plasma Reformer (플라즈마를 이용한 FGR 기반 저 NOx 연소 타당성 연구)

  • Kim, Kwan-Tae;Lee, Dae-Hoon;Cha, Min-Suk;Keel, Sang-In;Yun, Jin-Han;Kim, Dong-Hyun;Song, Young-Hoon
    • Journal of the Korean Society of Combustion
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    • v.12 no.3
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    • pp.1-7
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    • 2007
  • A combined hydrogen generator of plasma and catalytic reformer was developed, and was applied to stabilize unstable flame of 200,000 Kcal/hr LPG combustor. The role of the plasma reformer was to generate hydrogen in a short period and to heat-up the catalytic reformer during the start-up time. After the start-up period, the catalytic reformer generates hydrogen through steam reforming with oxygen (SRO) reactions. The maximum capacity of the hydrogen generator was enough 100 lpm to stabilize the flame of the present combustor. In order to reduce NOx and CO emissions simultaneously, 1) FGR (Flue Gas Recirculation) technique has been adopted and 2) the hydrogen was added into the fuel supplied to the combustor. Test results showed that the addition of 25% hydrogen and 30% FGR rate lead to simultaneous decrease of CO and NOx emissions. The technique developed in the present study showed good potential to replace $NH_3$ SCR technique, especially in the small-scale combustor applications.

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Numerical study on operating parameters of autothermal reformer for hydrogen production (수소생산을 위한 자열개질기 작동조건의 수치해석 연구)

  • Park, Joon-Guen;Lee, Shin-Ku;Lim, Sung-Kwang;Bae, Joong-Myeon
    • 한국신재생에너지학회:학술대회논문집
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    • pp.507-510
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    • 2008
  • Characteristics of an autothermal reformer at various operating parameters have been studied in this paper. Numerical method has been used, and simulation model has been developed for the analysis. Full Combustion reaction, Steam Reforming(SR) reaction, Water-Gas Shift(WGS) reaction, and Direct Steam Reforming(DSR) reaction are assumed as dominant chemical reactions in the autothermal reformer. Simulation results are compared with experimental results for code validation. Operating parameters of the autothermal reformer are inlet temperature, Oxygen to Carbon Ratio(OCR), Steam to Carbon Ratio(SCR), and Gas Hourly Space Veolcity(GHSV). SR reaction rate decreases with low inlet temperature. If OCR is increased, $H_2$ yield is increased but optimal point is suggested. WGS reaction is activated with high SCR. When GHSV is increased, reforming efficiency is increased but pressure drop may decrease the system efficiency.

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Effect of Pilates Reformer Training on Gait Improvement of Subjects with Asymmetric Pelvic Rotation (필라테스 리포머 운동이 비대칭 골반 돌림을 가진 대상자의 보행 개선에 미치는 효과)

  • Moon, Ok-Kon;Han, Song-E
    • Korean Journal of Sport Biomechanics
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    • v.23 no.3
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    • pp.271-278
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    • 2013
  • The purpose of this study was to determine the effect of Pilates Reformer training on gait improvement of subjects with asymmetric pelvic rotation. The seven subjects with greater pelvic rotation in right swing were assessed twice, 4 weeks apart, during which there was submitted to a Pilates Reformer training (three 40 min session per week). The kinematic data consisted of pelvic rotation and flexion angle of hip and knee joint was measured during gait. In comparison between both leg swings, max, min and range values of pelvic rotation was not significantly difference. After training, range of pelvic rotation in right swing was significantly decreased, but in left swing was not. In comparison between both leg swings, the values of max of hip and knee joint angle was significantly difference. After training, max values of angle of knee joint in right swing was significantly increased, but in left swing was not. The result of this study revealed that Pilates Reformer training was effective in improving gait to symmetric pelvic rotation.

Numerical Study on Correlation between Operating Parameters and Reforming Efficiency for a Methane Autothermal Reformer (천연가스 자열개질기를 위한 작동조건과 개질효율의 상관관계에 대한 수치해석 연구)

  • Park, Joon-Guen;Lee, Shin-Ku;Lim, Sung-Kwang;Bae, Joong-Myeon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.32 no.8
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    • pp.636-644
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    • 2008
  • The objective of this paper is to investigate characteristics of an autothermal reformer at various operating conditions. Numerical method has been used, and simulation model has been developed for the analysis. Pseudo-homogeneous model is incorporated because the reactor is filled with catalysts of a packed-bed type. Dominant chemical reactions are Full Combustion reaction, Steam Reforming(SR) reaction, Water-Gas Shift(WGS) reaction, and Direct Steam Reforming(DSR) reaction. Simulation results are compared with experimental results for code validation. Operating parameters of the autothermal reformer are inlet temperature, Oxygen to Carbon Ratio(OCR), Steam to Carbon Ratio(SCR), and Gas Hourly Space Velocity(GHSV). Temperature at the reactor center, fuel conversion, species at the reformer outlet, and reforming efficiency are shown as simulation results. SR reaction rate is improved by increased inlet temperature. Reforming efficiency and fuel conversion reached the maximum at 0.7 of OCR. SR reaction and WGS reaction are activated as SCR increases. When GHSV is increased, reforming efficiency increases but pressure drop from the increased GHSV may decrease the system efficiency.

Numerical Study on Operating Parameters and Shapes of a Steam Reformer for Hydrogen Production from Methane (천연가스로부터 수소를 생산하기 위한 수증기 개질기의 작동조건과 형상에 대한 수치해석 연구)

  • Park, Joong-Uen;Lee, Shin-Ku;Lim, Sung-Kwang;Bae, Joong-Myeon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.33 no.1
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    • pp.60-68
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    • 2009
  • The steam reformer for hydrogen production from methane is studied by a numerical method. Langmuir- Hinshelwood model is incorporated for catalytic surface reactions, and the pseudo-homogeneous model is used to take into account local equilibrium phenomena between a catalyst and bulk gas. Dominant chemical reactions are Steam Reforming (SR) reaction, Water-Gas Shift (WGS) reaction, and Direct Steam Reforming (DSR) reaction. The numerical results are validated with experimental results at the same operating conditions. Using the validated code, parametric study has been numerically performed in view of the steam reformer performance. As increasing a wall temperature, the fuel conversion increases due to the high heat transfer rate. When Steam to Carbon Ratio (SCR) increases, the concentration of carbon monoxide decreases since WGS reaction becomes more active. When increasing Gas Hourly Space Velocity (GHSV), the fuel conversion decreases due to the heat transfer limitation and the low residence time. The reactor shape effects are also investigated. The length and radius of cylindrical reactors are changed at the same catalyst volume. The longer steam reformer is, the better steam reformer performs. However, system energy efficiency decreases due to the large pressure drop.

A Study on the Development of Ultrasonic Scanning Device for the Inspection and Evaluation of Creep Damage of HK - 40 Reformer Tube Welded Zone (HK-40 고온반응관 용접부의 Creep손상 진단기법 및 자동 초음파탐상장치의 개발에 관한 연구)

  • Cho, K.S.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.9 no.1
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    • pp.98-105
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    • 1989
  • Detection of creep damages in centrifugally cast HK-40 reformer furnace catalyst tube is a common problem for the safety and scheduled operation of chemical plants. This study was focused on the development of an automatic ultrasonic scanning device with which the creep damage of welded zone of HK-40 reformer tubes is detected and evaluated.

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A Study on Optimization of Reformer for kW Class SOFC System (kW급 SOFC 시스템용 개질기 최적화)

  • YI, YONG;PARK, SE JIN;KIM, MIN SOO;SHIN, JANG SIK;SHIN, SEOCK JAE
    • Transactions of the Korean hydrogen and new energy society
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    • v.29 no.4
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    • pp.317-323
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    • 2018
  • Solid oxide fuel cell (SOFC) operates at high temperature, therefor has the advantage of higher power generation and using exhaust heat than other fuel cells. In particular, the reforming reaction can be performed inside the SOFC stack to reduce the cooling of the stack and the burden on the reformer reactor. In this study, the reformer structure, operating characteristics, and thermal efficiency were evaluated for the optimization design of a heat exchanger type reformer of a 1 kW SOFC system.