Lab-scale 기포유동층 반응기(D=0.1 m, H=1.5 m)에서 왕겨와 모래를 혼합하여 가스화를 통해 합성가스를 얻고 남은 왕겨 회재는 고부가가치 물질로 사용하기 위한 연구의 선행연구로서 왕겨/ 유동사/ 왕겨 회재(실리카)의 혼합 및 유동특성을 규명하였다. 왕겨/유동사를 5:95, 10:90, 20:80, 30:70의 부피비로 유속 범위(0~0.63 m/s)조건으로 수행하였으며, 또한 왕겨 회재는 왕겨를 기준으로 부피비 6%로 결정하였다. 왕겨/유동사, 왕겨/유동사/왕겨 회재의 혼합실험을 통해 왕겨 부피비 0%, 5%, 10%에서는 최소유동화속도가 0.19~0.21m/s임을 확인하였고, 20%일때는 0.3m/s로 증가하였으며, 30%일때는 분리현상이 나타나 최소유동화속도가 측정 되지 않았다. 또한, 실험데이터에 따라 Brereton과 Grace의 mixing index를 이용하여 각 조건 별로 mixing index값을 도출한 결과 왕겨/유동사의 혼합은 0.8~1, 왕겨/유동사/왕겨 회재의 혼합은 0.88~1 사이임을 확인하였다. 이를 통하여 왕겨/유동사의 혼합과 왕겨/유동사/왕겨 회재 혼합의 최적 조업조건을 도출할 수 있었으며, 운전조건을 결정할 수 있었다.

We investigate fluidization characteristics of the mixture of rice husk, silica sand and rice husk ash as a preliminary study for valuable utilization of rice husk ash obtained from gasification of rice husk in a fluidized bed reactor. As experiment valuables, the blending ratio of rice husk and sand (rice husk: sand) is selected as 5:95, 10:90, 20:80 and 30:70 on a volume base. Rice husk ash was added with 6 vol% of rice husk for each experiment and air velocity to the reactor was 0~0.63 m/s. In both rice husk/sand and rice husk/sand/ash mixture, the minimum fluidization velocity (Umf) is observed as 0.19~0.21 m/s at feeding of 0~10 vol.% of rice husk and 0.30 m/s at feeding of 20 vol.% of rice husk. With increasing the amount of rice husk up to 30 vol.%, Umf can not measure due to segregation behavior. The mixing index for each experiment is determined using mixing index equation proposed by Brereton and Grace. The mixing index of the mixture of rice husk/sand and rice husk/sand/ash was 0.8~1 and 0.88~1, respectively. The optimum fluidization condition was found for the good mixing and separation of rice husk ash.

Rice Husk Silica Sand Rice Husk Ash Flow Mixing Fluidized Bed

Lee WJ, “A Research on the Gas Flow through Nano Space Network in Rice Husk Silica Layer,” M.S. Dissertation, Chonnam National University(2013).
KIER Research Report, Energy production through rice husk gasification and development of anode materials for rechargeable battery(2014).
No SY, J. Biosystems Eng., 23, 507 (1998)
Kumar A, Mohanta K, Kumar D, Parkash O, Int. J. Eng. Technol. Adv. Eng., 2, 2250 (2012)
So SJ, “Characterization, Size Reduction and Biological Effect of a BPNM, Rice Husk Silica,” Ph.D. dissertation, Chonnam National University(2012).
Son SM, Kim UY, Shin IS, Kang Y, Choi MJ, Korean Chem. Eng. Res., 46(4), 707 (2008)
Lee CG, Kim JS, Song PS, Cho YJ, Kang Y, Choi MJ, HWAHAK KONGHAK, 40(4), 445 (2002)
Rao TR, Bheemarasetti JVR, Energy, 26(6), 633 (2001)
Cha WS, Hong SC, Oh KJ, Doh DS, HWAHAK KONGHAK, 30(6), 641 (1992)
Shin YS, J. Environ. Sci. Tech Res., 10, 49 (2000)
Fang M, Yang L, Chen G, Shi Z, Luo Z, Cen K, Fuel Process. Technol., 85(11), 1273 (2004)
Alavi S, Caussat B, Powder Technol., 157(1-3), 114 (2005)
Sharma AM, Kumar A, Patil KN, Huhnke RL, Powder Technol., 235, 661 (2013)
Geldart D, Powder Technol., 7, 285 (1973)
Rozainee M, “Production of Amorphous Silica from Rice Husk in Fluidised Bed System,” Ph.D. dissertation, Universiti Teknologi Malaysia(2007).
Wen CY, Yu YH, AIChE J., 12, 610 (1966)
Haider A, Levenspiel O, Powder Technol., 58, 63 (1989)
Brereton CMH, Grace JR, Chem. Eng. Sci., 48, 2565 (1993)
Kim DY, “A Study on the Flow Characteristics of Fine Particle in a Gas-Solid Fluidized Beds with Binary Particle,”M.S. Dissertation, Sungkyunkwan University(2013).
Kim DY, Rim GH, Lee DH, Powder Technol., 258, 344 (2014)
Huang S, Jing S, Wang JF, Wang ZW, Jin Y, Powder Technol., 117(3), 232 (2001)
Sen R, Gosh DN, Ind. Chem. Eng., 34, 206 (1992)
Rozainee M, Ngo SP, Salema AA, Tan KG, Ariffin M, Zainura ZN, Bioresour. Technol., 99(4), 703 (2008)
Martinez JD, Pineda T, Lopez JP, Betancur M, Energy, 36(6), 3846 (2011)
Chandrasekhar S, Satyanarayana KG, Pramada PN, Raghavan P, Gupta TN, J. Mater. Sci., 38(15), 3159 (2003)
Zhang Y, Jin BS, Zhong WQ, Chem. Eng. Process., 48(3), 745 (2009)
Formisani B, Girimonte R, KONA, 21, 66 (2003)
Azadi M, Korean J. Chem. Eng., 28(7), 1599 (2011)