水平双管程液-固循环流化床中颗粒分布和压降

摘要为促进流化床换热防垢节能技术在水平双管程换热器中的应用，设计和构建了一套冷模透明水平双管程液-固循环流化床换热装置。以水和聚甲醛颗粒为工质，利用电荷耦合器件（CCD）图像测量和处理系统及压差传感器，考察了颗粒加入量（0.50%~1.25%）和循环流量（6~11 m³·h^-1）对颗粒分布和压降的影响。结果表明：上管程的颗粒分布更为均匀，下管程内存在“死区”，上、下管程的固含率均沿重力方向增大。上管程的颗粒分布不均匀度随循环流量的增加而波动，下管程则先迅速增大再逐渐减小。上、下管程的颗粒分布不均匀度均随颗粒加入量的增加而波动。压降比率随循环流量和颗粒加入量的增加而波动，在实验范围内的最大值为18.3%。绘制了操作参数对颗粒分布和压降影响的三维图，以确定较适宜的操作参数范围。

	Service

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	Email Alert
	RSS
	作者相关文章
	姜峰
	王锦锦
	齐国鹏
	梁旭
	韩妮莎
	李修伦

关键词：颗粒分布；压降；液-固循环流化床换热器；水平双管程

Abstract： To promote the application of the fluidized bed heat-transfer and anti-scaling technology in the horizontal two-pass heat exchanger, a set of cold-model two-pass liquid-solid circulating fluidized bed heat exchanger with transparent horizontal tube bundle was designed and built. Water and polyformaldehyde particles were selected as the working media. The effects of the operating parameters, such as the amount of added particles (0. 50%-1. 25%) and circulation flow rate (6-11 m³·h^-1), on the particle distribution and pressure drop were investigated by using a charge-coupled device (CCD) and a differential pressure transmitter. Results show that the particle distribution in the upper tube pass is relative uniform, while that in the lower tube pass is nonuniform. The solid holdups in the upper and lower tube passes both increase along the gravitational direction. A "dead zone" with low solid holdup exists in the lower tube pass, which is not beneficial to the heat transfer enhancement and fouling prevention. With the increase in circulation flow rate, the non-uniformity of particle distribution in the upper tube pass fluctuates, but that in the lower tube pass initially rapidly increases and then gradually decreases. The non-u-niformity of particle distribution in the upper and lower tube passes fluctuates with the increase in the amount of added particles. The pressure drop ratio fluctuates with the increase in circulation flow rate and the amount of added particles, and the maximum pressure drop ratio is 18. 3% within the experimental range. The three-dimensional diagrams of the effect of the operating parameters on the particle distribution and pressure drop are established to determine the proper range of operating parameter.

Keywords： particle distribution； pressure drop； liquid-solid circulating fluidized bed heat exchanger； horizontal two-pass

Received 2020-05-12;

Fund:化学工程国家重点实验室开放项目（SKL CHE-18B03）；天津市科技支撑计划重点项目（99ZCKFGX01900）。

Corresponding Authors: 姜峰,E-mail:jiangfeng@tju.edu.cn。 Email: jiangfeng@tju.edu.cn

About author: 姜峰(1975-),男,博士,副教授,现从事多相流强化传热与防、除垢方面的研究。

引用本文:

姜峰, 王锦锦, 齐国鹏, 梁旭, 韩妮莎, 李修伦.水平双管程液-固循环流化床中颗粒分布和压降[J]. 化学工业与工程, 2021,38(2): 30-38,68

Jiang Feng, Wang Jinjin, Qi Guopeng, Liang Xu, Han Nisha, Li Xiulun.Particle Distribution and Pressure Drop in a Horizontal Two-pass Liquid-solid Circulating Fluidized Bed[J]. Chemcial Industry and Engineering, 2021,38(2): 30-38,68

[1] 陈健生, 李修伦. 汽液固三相循环流化床蒸发器强化传热和防垢研究[J]. 化学工业与工程, 2000, 17(1):15-18, 62 Chen Jiansheng, Li Xiulun, Zhang Shaofeng, et al. Studies of heat transfer enhancement and fouling prevention in a vapor liquid solid three phase circulating fluidized bed evaporator[J]. Chemical Industry and Engineering, 2000, 17(1):15-18, 62(in Chinese)
[2] Müller-Steinhagen H. Heat transfer fouling:50 years after the kern and seaton model[J]. Heat Transfer Engineering, 2011, 32(1):1-13
[3] Jiang F, Yang M, Qi G, et al. Heat transfer and antiscaling performance of a Na₂SO₄ circulating fluidized bed evaporator[J]. Applied Thermal Engineering, 2019, 155:123-134
[4] Haid M. Correlations for the prediction of heat transfer to liquid-solid fluidized beds[J]. Chemical Engineering and Processing:Process Intensification, 1997, 36(2):143-147
[5] Ma Y, Liu M, An M, et al. Experimental investigation of collision behavior of fluidized solid particles on the tube wall of a graphite evaporator by vibration signal analysis[J]. Powder Technology, 2017, 316:303-314
[6] Jiang F, Feng Q, Qi G, et al. Flow boiling in a downflow circulating fluidized bed evaporator[J]. Applied Thermal Engineering, 2019, 156:359-370
[7] Hu X, Xu T, Li C, et al. Catalytic cracking of n-heptane under activation of lattice oxygen in a circulating fluidized bed unit[J]. Chemical Engineering Journal, 2011, 172(1):410-417
[8] Chowdhury N, Zhu J, Nakhla G, et al. A novel liquid-solid circulating fluidized-bed bioreactor for biological nutrient removal from municipal wastewater[J]. Chemical Engineering & Technology, 2009, 32(3):364-372
[9] Aghajani M, Müller-Steinhagen H, Jamialahmadi M. New design equations for liquid/solid fluidized bed heat exchangers[J]. International Journal of Heat and Mass Transfer, 2005, 48(2):317-329
[10] Meijer J A M. Prevention of calcium sulfate scale deposition by a fluidized bed[J]. Desalination, 1983, 47(1/2/3):3-15
[11] 齐国鹏, 王兵兵, 姜峰, 等. 循环流化床蒸发器中的压降与颗粒分布的研究[J]. 化学工业与工程, 2013, 30(3):66-70 Qi Guopeng, Wang Bingbing, Jiang Feng, et al. Pressure drop and particles distribution in the vapor-liquid-solid multi-pipe circulating fluidized bed evaporator[J]. Chemical Industry and Engineering, 2013, 30(3):66-70(in Chinese)
[12] Pronk P, Infante Ferreira C A, Witkamp G J. Prevention of fouling and scaling in stationary and circulating liquid-solid fluidized bed heat exchangers:Particle impact measurements and analysis[J]. International Journal of Heat and Mass Transfer, 2009, 52(15/16):3857-3868
[13] Arumemi-Ikhide M, Sefiane K, Duursma G, et al. Investigation of flow boiling in circulating three-phase fluidised bed:Part I:Experiments and results[J]. Chemical Engineering Science, 2008, 63(4):881-895
[14] Arumemiikhide M, Sefiane K, Duursma G, et al. Investigation of flow boiling in circulating three-phase fluidised bed Part II:Theoretical correlation[J]. Chemical Engineering Science, 2008, 63(4):896-914
[15] Roy S, Chen J, Kumar S, et al. Tomographic and particle tracking studies in a liquid-solid riser[J]. Industrial & Engineering Chemistry Research, 1997, 36(11):4666-4669
[16] Roy S, Kemoun A, Aldahhan M H, et al. Experimental investigation of the hydrodynamics in a liquid-solid riser[J]. AIChE Journal, 2005, 51(3):802-835
[17] Li N, Jiang F, Han X, et al. Study on the particle distribution of a two-pass circulating fluidized bed evaporator with baffle[J]. Powder Technology, 2016, 295:47-58
[18] Li N, Zhang Y, Jiang F, et al. Effects of particle size on the particle distribution of a two-pass circulating fluidized bed evaporator with a baffle[J]. Powder Technology, 2017, 311:456-464
[19] Jiang F, Zhao P, Qi G, et al. Flow characteristics in a horizontal liquid-solid circulating fluidized bed[J]. Powder Technology, 2019, 342:24-35
[20] Jiang F, Bian Y, Qi G, et al. Study on the particle distribution of a horizontal multi-tube circulating fluidized bed[J]. Powder Technology, 2016, 295:272-283
[21] Qi G, Jiang F. Numerical investigation on prevention of fouling in the horizontal tube heat exchanger:Particle distribution and pressure drop[J]. Desalination, 2015, 367:112-125
[22] 张少峰, 王江涛, 刘燕. Kenics静态混合器在水平液固循环流化床中的研究[J]. 化学工程, 2012, 40(6):43-46 Zhang Shaofeng, Wang Jiangtao, Liu Yan. Kenics static mixer in liquid-solid horizontal circulating fluidized bed[J]. Chemical Engineering, 2012, 40(6):43-46(in Chinese)
[23] 张少峰, 张伟, 刘燕. 起旋器对水平液固循环流化床颗粒分布的影响[J]. 河北工业大学学报, 2009, 38(2):69-73 Zhang Shaofeng, Zhang Wei, Liu Yan. Effects of the spiral flow generator on particles distribution in liquid-solid horizontal circulating fluidized bed[J]. Journal of Hebei University of Technology, 2009, 38(2):69-73(in Chinese)
[24] 巩国栋. 水平多管液固循环流化床颗粒分布性能的实验研究[D]. 天津:河北工业大学, 2007 Gong Guodong. Experimental study on particle distribution performance of horizontal liquid-solid circulating fluidized bed[D]. Tianjin:Hebei University of Technology, 2007(in Chinese)
[25] Monji H, Matsui G, Saito T. Pressure drop reduction of liquid-particles two-phase flow with nearly equal density[J]. Multiphase Flow, 1995, 7(2):355-365