窑内弥散介质的辐射传递特性及温度场重建研究
|
摘要
焚烧法因为其物料适应性广、减量化、无害化等明显优点已成为发达国家处理废弃物的主要途径,在我国主要城市也已建立了焚烧处理厂,开始这方面的研究。但同时,研究指出垃圾焚烧也已成为剧毒物质二噁英类化合物产生的主要来源。
目前普遍认为二噁英类化合物的生成与窑内温度场分布有着密切联系,同时焚烧炉内的温度场分布对于焚烧系统的稳定运行、减少窑内结渣等也有着重要意义。而目前典型的废弃物焚烧系统对温度监控仍采用热电偶式测温装置,无法反应整个焚烧系统内实际温度的分布情况。因此本文基于对弥散介质的辐射传递特性的计算方法的研究,尝试将利用火焰辐射对焚烧炉内截面温度场反演重建的技术应用于回转窑焚烧炉。
首先基于Mie散射理论,对球形固体颗粒的辐射特性进行了研究；并计算了回转窑内碳粒及飞灰粒子云的辐射特性参数。对于气体介质的辐射特性参数计算,比较了谱带模型法和逐线计算法的差异,认为谱带模型法的计算精度适用于工程应用,可用于焚烧炉内混合气体的辐射参数计算。随后使用Fluent对废弃物回转窑焚烧状况作了数值模拟,得出了燃烧空间内的温度场分布及气体介质浓度场分布。在此基础上对红外热像仪的发射率设置进行了计算。
最终以两段式回转窑焚烧炉为研究对象,基于逆向Monte Carlo方法,提出了利用电荷耦合器件摄像机所获取的辐射信息进行炉膛断面二维弥散介质温度场快速重建的模型。应用最小二乘QR(LSQR)矩阵分解算法结合维恩定律即可重建出截面温度场。并进行了现场试验研究,试验结果证实了重建方法的可行性和实用性。
Incinerating the wastes has become the main way in developed countries because of its wide adaptability and other obvious advantages. Some incineration plants also have been established in our major cities. However, it's reported that waste incineration has become the main source of the formation of dioxin-like c ompounds.
It's widely accepted that the formation of dioxins is closely linked to the kiln temperature distribution, while the temperature distribution of the incinerator is important for the stable operation of burning system and reduction of slagging. However traditional power station boilers and waste incinerators are still using thermocouples for temperature monitoring, which can not reflect the actual temperature field of the incinerator. So we tried to reconstruct the temperature distribution of a kiln incinerator.
The radiative property of the solid particles was discussed and calculated based on Mie scattering theories. The line-by-line model and band model have been used to calculate the absorption coefficient of molecular gases, and we found that the band model is good enough for engineering. Then we used fluent to simulate the combusting in a kiln incinerator, obtained both the temperature distribution and gas concentration distribution. Then the radiation parameters of the medium were calculated for the emissivity setting of a Infrared Thermograpic Camera.
At last we attempted to reconstruct the 2D temperature distribution of a rotary kiln hazardous waste incinerator. A reconstruction model of temperature distribution based on the back-Monte Carlo method was proposed, using the flame images captured by charge-coupled device cameras. A matrix-decomposition-based least squares algorithm was introduced to reconstruct the emission intensity distribution in the kiln sections. The proposed method was found to be capable and effective through practical approaches.
目前普遍认为二噁英类化合物的生成与窑内温度场分布有着密切联系,同时焚烧炉内的温度场分布对于焚烧系统的稳定运行、减少窑内结渣等也有着重要意义。而目前典型的废弃物焚烧系统对温度监控仍采用热电偶式测温装置,无法反应整个焚烧系统内实际温度的分布情况。因此本文基于对弥散介质的辐射传递特性的计算方法的研究,尝试将利用火焰辐射对焚烧炉内截面温度场反演重建的技术应用于回转窑焚烧炉。
首先基于Mie散射理论,对球形固体颗粒的辐射特性进行了研究；并计算了回转窑内碳粒及飞灰粒子云的辐射特性参数。对于气体介质的辐射特性参数计算,比较了谱带模型法和逐线计算法的差异,认为谱带模型法的计算精度适用于工程应用,可用于焚烧炉内混合气体的辐射参数计算。随后使用Fluent对废弃物回转窑焚烧状况作了数值模拟,得出了燃烧空间内的温度场分布及气体介质浓度场分布。在此基础上对红外热像仪的发射率设置进行了计算。
最终以两段式回转窑焚烧炉为研究对象,基于逆向Monte Carlo方法,提出了利用电荷耦合器件摄像机所获取的辐射信息进行炉膛断面二维弥散介质温度场快速重建的模型。应用最小二乘QR(LSQR)矩阵分解算法结合维恩定律即可重建出截面温度场。并进行了现场试验研究,试验结果证实了重建方法的可行性和实用性。
Incinerating the wastes has become the main way in developed countries because of its wide adaptability and other obvious advantages. Some incineration plants also have been established in our major cities. However, it's reported that waste incineration has become the main source of the formation of dioxin-like c ompounds.
It's widely accepted that the formation of dioxins is closely linked to the kiln temperature distribution, while the temperature distribution of the incinerator is important for the stable operation of burning system and reduction of slagging. However traditional power station boilers and waste incinerators are still using thermocouples for temperature monitoring, which can not reflect the actual temperature field of the incinerator. So we tried to reconstruct the temperature distribution of a kiln incinerator.
The radiative property of the solid particles was discussed and calculated based on Mie scattering theories. The line-by-line model and band model have been used to calculate the absorption coefficient of molecular gases, and we found that the band model is good enough for engineering. Then we used fluent to simulate the combusting in a kiln incinerator, obtained both the temperature distribution and gas concentration distribution. Then the radiation parameters of the medium were calculated for the emissivity setting of a Infrared Thermograpic Camera.
At last we attempted to reconstruct the 2D temperature distribution of a rotary kiln hazardous waste incinerator. A reconstruction model of temperature distribution based on the back-Monte Carlo method was proposed, using the flame images captured by charge-coupled device cameras. A matrix-decomposition-based least squares algorithm was introduced to reconstruct the emission intensity distribution in the kiln sections. The proposed method was found to be capable and effective through practical approaches.
引文
[1]朱江,蒋旭光,刘刚,严建华,池涌.回转窑处理危险废弃物技术探讨.环境工程.2004,22(5)：57-61.
[2]刘刚.典型危险废物回转窑热处置特性和技术研究：浙江大学博士学位论文,2006.
[3]Visvanathan C. Hazardous Waste Disposal. Resources, Conservation and Recycling. 1996,16:201-212.
[4]朱江.典型危险废弃物的热处置基础研究：浙江大学硕士论文,2005.
[5]周苗生,汤国伟.危险废物回转窑焚烧系统的工艺设计.环境污染与防治.2001,23(6)：299-301.
[6]Oppelt E T. Hazardous waste destruction. Environmental Science Technology.1986,20(4): 312-318.
[7]张孝彬,王俊莲,陶新永,郭云,张锦锡,杨杭生,彭必先.医疗废弃物焚烧处理概况.环境污染与防治.2007,11：1-15.
[8]Ni Y W, Zhang H J, Fan S, Zhang X P, Zhang Q, Chen J P. Emissions of PCDD/Fs from municipal solid waste incinerators in China. Combust and Flame.2009,156:2084-2092.
[9]Reiner E J, Clement R E, Okey A B, Marvin C H. Advances in analytical techniques for polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like PCBs. Analytical and bioanalytical chemistry.2006,386:791-806.
[10]姜欣.日本对二嗯英的研究现状.皮革化工.2006,23(5)：39-42.
[11]尹雪峰,李晓东,罗建松,陆胜勇,谷月玲,严建华,倪明江,岑可法.温度和气氛对PAHs由从头合成反应生成PCDD/Fs的作用.燃烧科学与技术.2008,14(2)：117-121.
[12]Wang D L, Xu X B, Zheng M H, Chung H C. Effect of copper chloride on the emissions of PCDD/Fs and PAHs from PVC combustion. Chemosphere.2002,48:857-863.
[13]Hatanaka T, Imagawa T, Takeuchi M. Effects of copper chloride on formation of polychlorinated dibenzo-p-dioxins in model waste incineration. Chemosphere. 2003,51:1041-1046.
[14]Chang M B, Huang T F. The effects of temperature and oxygen content on the PCDD/PCDFs formation in MSW fly ash. Chemosphere.2000,40:159-164.
[15]陆胜勇,严建华,李晓东,陈彤,倪明江,岑可法.废弃物焚烧飞灰中从头合成二嗯英的试验研究--氧、碳、催化剂的影响.中国电机工程学报.2003,23(11)：178-183.
[16]Kohse-Hoinghaus K, Barlow R S, Aldeen M, Wolfrum J. Combustion at the focus:laser diagnostics and control. Proceedings of the Combustion Institute.2005,30:89-123.
[17]Hernandez R, Balleste J. Flame imaging as a diagnostic tool for industrial combustion. Combustion and Flame.2008,155:509-528.
[18]Lu G, Yan Y, Colechin M J F. A digital imaging based multi-functional flame monitoring system IEEE transactions on instrumentation and Measurement.2004,53(4):1520-1158.
[19]Brisley P M, Lu G, Yan Y. Three-dimensional temperature measurement of combustion flames using a single monochromatic CCD camera. Instrumentation and Measurement Technology Conference, Como, Italy,2004.
[20]Huang Q X, Wang F, Liu D, Ma Z Y, Yan J H, Chi Y, Cen K F. Reconstruction of soot temperature and volume fraction profiles of an asymmetric flame using stereoscopic tomography. Combustion and Flame.2009,156:565-573.
[21]Lou C, Zhou H C, Deduction of the two-dimensional distribution of temperature in a cross section of a boiler furnace from images of flame radition, Combustion and Flame. 2005,143:97-105.
[22]Zhou H C, Han S D, Sheng F, Zheng C G. Visualization of three-dimensional temperature distributions in a large-scale furnace via regularized reconstruction from radiative energy images: Numerical studies. Journal of Quantitative Spectroscopy & Radiative Transfer.2002, 72(4):361-383.
[23]Zhou H C, Lou C, Cheng Q, Jiang Z, He J, Huang B, Pei Z, Lu C, Experimental investigations on visualization of three-dimensional temperature distributions in a large-scale pulverized-coal-fired boiler furnace. Proceedings of the Combustion Institute.2005, 30:1699-1706.
[24]Manca D, Rovaglio M. Infrared thermographic image processing for the operation and control of heterogeneous combustion chambers. Combustion and Flame.2002,130:277-297.
[25]郑楚光,柳朝晖.弥散介质的光学特性及辐射传热.武汉：华中理工大学出版社,1996.
[26]Modest M F. Radiative Heat Transfer.2nd ed. USA:Elsevier,2003.
[27]黄群星.炉内弥散介质辐射传递特性及燃烧过程优化控制研究：浙江大学博士论 文,2005.
[28]Dazell. W H, Sarofim A F. Optical constants of soot and their application to heat-flux calculations, ASME journal of heat transfer.1978,91:100-104.
[29]刘林华,余其铮,谈和平.国产动力煤煤粉粒子系的辐射特性.动力工程.1998,18(3)：65-69.
[30]刑华伟,郑楚光.煤粉炉内颗粒光学特性实验与数值模型.燃烧科学与技术.2002,8(1)：34-37.
[31]Edwars D K. Molecular gas band radiation. Advances in heat transfer.1976,12:115-193.
[32]石广玉.大气辐射学.科学出版社,2007.
[33]刘林华,谈和平,余其铮.气体污染物的红外辐射特性.燃烧科学与技术.1999,5(3)：251-255.
[34]董士奎,余其铮,刘林华,谈和平.一种新的CO2高温辐射特性窄谱带模型参数计算方法.工程热物理学报.2001,22：177-180.
[35]Whiting E E. An empirical approximation to the voigt profile. J. Quant. Spectro. Radiat. Transfer.1968,8:1379-1384.
[36]Li W M, Tong T W, Dobranich D, Gritzo L A. A combined narrow and wide band model for computing the spectral absorption coefficient of CO2, CO, H2O, CH4, C2H2 and NO. J. Quant. Spectrasc. Radiat. Transfer.1995,54(6):961-970.
[37]张华,石广玉.一种快速高效的逐线积分大气吸收计算方法.大气科学.2000,24(1)：111-121.
[38]尹雪梅,刘林华.高温气体辐射特性计算模型.热能动力工程.2007,22(5)：473-479.
[39]刘林华,余其铮,阮立明,谈和平.煤粉燃烧产物的辐射特性.动力工程.1996,16(6)：14-21.
[40]Yamada Y, Catrigny J D, Tien C L. Radiative transfer with dependent scattering by particles. J. Heat Transfer,1986,108:614-618.
[41]Singh B P, Kaviany M. Independent theory versus direct simulation of radiation heat transfer in packed beds. Int. J. Heat Mass Transfer,1991,34(11):2869-2882.
[42]Wall T F, Bhattacharya S P, Zhang D K, Gupta R P, He X. The properties and thermal effects of ash deposits on coal-fired furnaces. Progress in Energy and Combustion Science,1993,19(6):487-504.
[43]秦岭,班金城.电站锅炉数值计算建模及网格划分的探讨.研究与探讨.能源工程.2009,4：13-16.
[44]潘维,池作和,斯东波,阮涛,岑可法.四角切圆燃烧锅炉炉膛网格生成方法的研究.动力工程,2005,25(3)：359-363.
[45]董小瑞,刘汉涛,张翼等.125MW煤粉炉内分级燃烧的数值模拟.煤炭转化.2008,31(1)：66-70.
[46]路涛.四角切圆燃烧锅炉中SNCR过程的数值模拟：华北电力大学硕士学位论文,2004.
[47]赵立业,辛国华.600MW四角切圆燃烧锅炉炉内过程的数值模拟.东北电力大学学报.2008,28(6)：48-52.
[48]Paige C C, Saunders M A. LSQR-An Algorithm for Sparse Linear-Equation and Sparse Least-Squares. ACM Transactions on Mathematical Software,1982,8 (2):43-71.
[49]Liu D, Wang F, Cen K F, Yan J H, Huang Q X, Chi Y. Noncontact temperature measurement by means of CCD cameras in a participating medium. Optics Letters,2008,33 (5):422-424.
[50]刘冬.弥散介质温度场重建的辐射反问题研究：浙江大学博士学位论文,2010.
[51]中国环境年鉴2005.北京：中国环境年鉴社,2005.
[52]中国环境年鉴2006.北京：中国环境年鉴社,2006.
[53]中国环境年鉴2007.北京：中国环境年鉴社,2007.
[54]中国环境年鉴2008.北京：中国环境年鉴社,2008.
[55]中国环境年鉴2009.北京：中国环境年鉴社,2009.
[56]王飞.基于计算机图像处理技术的火焰温度场测量和燃烧诊断：浙江大学博士论文,2000.
[2]刘刚.典型危险废物回转窑热处置特性和技术研究：浙江大学博士学位论文,2006.
[3]Visvanathan C. Hazardous Waste Disposal. Resources, Conservation and Recycling. 1996,16:201-212.
[4]朱江.典型危险废弃物的热处置基础研究：浙江大学硕士论文,2005.
[5]周苗生,汤国伟.危险废物回转窑焚烧系统的工艺设计.环境污染与防治.2001,23(6)：299-301.
[6]Oppelt E T. Hazardous waste destruction. Environmental Science Technology.1986,20(4): 312-318.
[7]张孝彬,王俊莲,陶新永,郭云,张锦锡,杨杭生,彭必先.医疗废弃物焚烧处理概况.环境污染与防治.2007,11：1-15.
[8]Ni Y W, Zhang H J, Fan S, Zhang X P, Zhang Q, Chen J P. Emissions of PCDD/Fs from municipal solid waste incinerators in China. Combust and Flame.2009,156:2084-2092.
[9]Reiner E J, Clement R E, Okey A B, Marvin C H. Advances in analytical techniques for polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and dioxin-like PCBs. Analytical and bioanalytical chemistry.2006,386:791-806.
[10]姜欣.日本对二嗯英的研究现状.皮革化工.2006,23(5)：39-42.
[11]尹雪峰,李晓东,罗建松,陆胜勇,谷月玲,严建华,倪明江,岑可法.温度和气氛对PAHs由从头合成反应生成PCDD/Fs的作用.燃烧科学与技术.2008,14(2)：117-121.
[12]Wang D L, Xu X B, Zheng M H, Chung H C. Effect of copper chloride on the emissions of PCDD/Fs and PAHs from PVC combustion. Chemosphere.2002,48:857-863.
[13]Hatanaka T, Imagawa T, Takeuchi M. Effects of copper chloride on formation of polychlorinated dibenzo-p-dioxins in model waste incineration. Chemosphere. 2003,51:1041-1046.
[14]Chang M B, Huang T F. The effects of temperature and oxygen content on the PCDD/PCDFs formation in MSW fly ash. Chemosphere.2000,40:159-164.
[15]陆胜勇,严建华,李晓东,陈彤,倪明江,岑可法.废弃物焚烧飞灰中从头合成二嗯英的试验研究--氧、碳、催化剂的影响.中国电机工程学报.2003,23(11)：178-183.
[16]Kohse-Hoinghaus K, Barlow R S, Aldeen M, Wolfrum J. Combustion at the focus:laser diagnostics and control. Proceedings of the Combustion Institute.2005,30:89-123.
[17]Hernandez R, Balleste J. Flame imaging as a diagnostic tool for industrial combustion. Combustion and Flame.2008,155:509-528.
[18]Lu G, Yan Y, Colechin M J F. A digital imaging based multi-functional flame monitoring system IEEE transactions on instrumentation and Measurement.2004,53(4):1520-1158.
[19]Brisley P M, Lu G, Yan Y. Three-dimensional temperature measurement of combustion flames using a single monochromatic CCD camera. Instrumentation and Measurement Technology Conference, Como, Italy,2004.
[20]Huang Q X, Wang F, Liu D, Ma Z Y, Yan J H, Chi Y, Cen K F. Reconstruction of soot temperature and volume fraction profiles of an asymmetric flame using stereoscopic tomography. Combustion and Flame.2009,156:565-573.
[21]Lou C, Zhou H C, Deduction of the two-dimensional distribution of temperature in a cross section of a boiler furnace from images of flame radition, Combustion and Flame. 2005,143:97-105.
[22]Zhou H C, Han S D, Sheng F, Zheng C G. Visualization of three-dimensional temperature distributions in a large-scale furnace via regularized reconstruction from radiative energy images: Numerical studies. Journal of Quantitative Spectroscopy & Radiative Transfer.2002, 72(4):361-383.
[23]Zhou H C, Lou C, Cheng Q, Jiang Z, He J, Huang B, Pei Z, Lu C, Experimental investigations on visualization of three-dimensional temperature distributions in a large-scale pulverized-coal-fired boiler furnace. Proceedings of the Combustion Institute.2005, 30:1699-1706.
[24]Manca D, Rovaglio M. Infrared thermographic image processing for the operation and control of heterogeneous combustion chambers. Combustion and Flame.2002,130:277-297.
[25]郑楚光,柳朝晖.弥散介质的光学特性及辐射传热.武汉：华中理工大学出版社,1996.
[26]Modest M F. Radiative Heat Transfer.2nd ed. USA:Elsevier,2003.
[27]黄群星.炉内弥散介质辐射传递特性及燃烧过程优化控制研究：浙江大学博士论 文,2005.
[28]Dazell. W H, Sarofim A F. Optical constants of soot and their application to heat-flux calculations, ASME journal of heat transfer.1978,91:100-104.
[29]刘林华,余其铮,谈和平.国产动力煤煤粉粒子系的辐射特性.动力工程.1998,18(3)：65-69.
[30]刑华伟,郑楚光.煤粉炉内颗粒光学特性实验与数值模型.燃烧科学与技术.2002,8(1)：34-37.
[31]Edwars D K. Molecular gas band radiation. Advances in heat transfer.1976,12:115-193.
[32]石广玉.大气辐射学.科学出版社,2007.
[33]刘林华,谈和平,余其铮.气体污染物的红外辐射特性.燃烧科学与技术.1999,5(3)：251-255.
[34]董士奎,余其铮,刘林华,谈和平.一种新的CO2高温辐射特性窄谱带模型参数计算方法.工程热物理学报.2001,22：177-180.
[35]Whiting E E. An empirical approximation to the voigt profile. J. Quant. Spectro. Radiat. Transfer.1968,8:1379-1384.
[36]Li W M, Tong T W, Dobranich D, Gritzo L A. A combined narrow and wide band model for computing the spectral absorption coefficient of CO2, CO, H2O, CH4, C2H2 and NO. J. Quant. Spectrasc. Radiat. Transfer.1995,54(6):961-970.
[37]张华,石广玉.一种快速高效的逐线积分大气吸收计算方法.大气科学.2000,24(1)：111-121.
[38]尹雪梅,刘林华.高温气体辐射特性计算模型.热能动力工程.2007,22(5)：473-479.
[39]刘林华,余其铮,阮立明,谈和平.煤粉燃烧产物的辐射特性.动力工程.1996,16(6)：14-21.
[40]Yamada Y, Catrigny J D, Tien C L. Radiative transfer with dependent scattering by particles. J. Heat Transfer,1986,108:614-618.
[41]Singh B P, Kaviany M. Independent theory versus direct simulation of radiation heat transfer in packed beds. Int. J. Heat Mass Transfer,1991,34(11):2869-2882.
[42]Wall T F, Bhattacharya S P, Zhang D K, Gupta R P, He X. The properties and thermal effects of ash deposits on coal-fired furnaces. Progress in Energy and Combustion Science,1993,19(6):487-504.
[43]秦岭,班金城.电站锅炉数值计算建模及网格划分的探讨.研究与探讨.能源工程.2009,4：13-16.
[44]潘维,池作和,斯东波,阮涛,岑可法.四角切圆燃烧锅炉炉膛网格生成方法的研究.动力工程,2005,25(3)：359-363.
[45]董小瑞,刘汉涛,张翼等.125MW煤粉炉内分级燃烧的数值模拟.煤炭转化.2008,31(1)：66-70.
[46]路涛.四角切圆燃烧锅炉中SNCR过程的数值模拟：华北电力大学硕士学位论文,2004.
[47]赵立业,辛国华.600MW四角切圆燃烧锅炉炉内过程的数值模拟.东北电力大学学报.2008,28(6)：48-52.
[48]Paige C C, Saunders M A. LSQR-An Algorithm for Sparse Linear-Equation and Sparse Least-Squares. ACM Transactions on Mathematical Software,1982,8 (2):43-71.
[49]Liu D, Wang F, Cen K F, Yan J H, Huang Q X, Chi Y. Noncontact temperature measurement by means of CCD cameras in a participating medium. Optics Letters,2008,33 (5):422-424.
[50]刘冬.弥散介质温度场重建的辐射反问题研究：浙江大学博士学位论文,2010.
[51]中国环境年鉴2005.北京：中国环境年鉴社,2005.
[52]中国环境年鉴2006.北京：中国环境年鉴社,2006.
[53]中国环境年鉴2007.北京：中国环境年鉴社,2007.
[54]中国环境年鉴2008.北京：中国环境年鉴社,2008.
[55]中国环境年鉴2009.北京：中国环境年鉴社,2009.
[56]王飞.基于计算机图像处理技术的火焰温度场测量和燃烧诊断：浙江大学博士论文,2000.