热水解污泥流变特性及其对管道摩阻计算的影响
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摘要
通过热水解-中温厌氧消化联合工艺中热水解污泥流变特性试验,分析了TSS和温度对污泥屈服应力、极限黏度、稠度系数K和流动指数n等流变特征参数的影响。结果表明,热水解污泥可用Herschel-Bulkley模型进行描述;屈服应力和K值与TSS呈幂律关系,极限黏度与TSS呈指数关系,n值与TSS呈二次多项式关系;屈服应力、极限黏度和K值与温度的关系可用指数方程描述,n值与温度呈二次多项式关系;TSS>7.35%时,输运性能和可泵性变差。
The rheological characteristics of the thermal-hydrolyzed sludge in the process of thermal hydrolysis and mesophilic anaerobic digestion was investigated. The impacts of TSS and temperature on the rheological characteristic parameters including yield stress,limit viscosity,consistency coefficient(K) and flow index(n) were examined. Results showed that the rheological characteristics of the thermal-hydrolyzed sludge could be depicted by the Herschel-Bulkley model. Yield stress and K had a power relationship to TSS. Meanwhile,a exponential relationship between limit viscosity and TSS was demonstrated,and n presented a quadratic polynomial relationship to TSS. The relationship between temperature and yield stress,limit viscosity,and K could be described by the exponential equation. The n showed a quadratic polynomial relationship to the temperature. When TSS was higher than 7. 35%,the thermal-hydrolyzed sludge became difficult to transport or pump.
The rheological characteristics of the thermal-hydrolyzed sludge in the process of thermal hydrolysis and mesophilic anaerobic digestion was investigated. The impacts of TSS and temperature on the rheological characteristic parameters including yield stress,limit viscosity,consistency coefficient(K) and flow index(n) were examined. Results showed that the rheological characteristics of the thermal-hydrolyzed sludge could be depicted by the Herschel-Bulkley model. Yield stress and K had a power relationship to TSS. Meanwhile,a exponential relationship between limit viscosity and TSS was demonstrated,and n presented a quadratic polynomial relationship to TSS. The relationship between temperature and yield stress,limit viscosity,and K could be described by the exponential equation. The n showed a quadratic polynomial relationship to the temperature. When TSS was higher than 7. 35%,the thermal-hydrolyzed sludge became difficult to transport or pump.
引文
[1]徐慧敏,何国富,戴翎翎,等.低温热水解和超声联合破解污泥优化工艺的参数研究[J].中国环境科学,2016,36(4):1093-1098.
[2]朱敏.污水处理厂污泥管道输送系统设计与研究[J].给水排水,2012,38(增刊):22-25.
[3]Markis F,Baudez J C,Parthasarathy R,et al.The apparent viscosity and yield stress of mixtures of primary and secondary sludge:Impact of volume fraction of secondary sludge and total solids concentration[J].Chem Eng J,2016,288:577-587.
[4]Baudez J C.Physical aging and thixotropy in sludge rheology[J].Applied Rheology,2008,18(1):13459-13466.
[5]Baudez J C,Markis F,Eshtiaghi N,et al.The rheological behaviour of anaerobic digested sludge[J].Water Res,2011,45(17):5675-5680.
[6]Tixier N,Guibaud G,Baudu M,et al.Determination of some rheological parameters for the characterization of activated sludge[J].Bioresour Technol,2003,90(2):215-220.
[7]Eshtiaghi N,Markis F,Slatter P.The laminar/turbulent transition in a sludge pipeline[J].Water Sci Technol,2012,65(4):697-702.
[8]Baudez J C,Gupta R K,Eshtiaghi N,et al.The viscoelastic behaviour of raw and anaerobic digested sludge:strong similarities with soft-glassy materials[J].Water Res,2013,47(1):173-180.
[9]Yang F,Bick A,Shandalov S,et al.Yield stress and rheological characteristics of activated sludge in an airlift membrane bioreactor[J].J Membr Sci,2009,334(1/2):83-90.
[10]刘弦.城市污水处理厂污泥管道输送阻力特性研究[D].重庆:重庆大学,2007.
[11]Mika L.Rheological behaviour of low fraction ice slurry in pipes and pressure loss in pipe sudden contractions and expansions[J].International Journal of Refrigeration,2012,35(6):1697-1708.
[12]Slatter P.The hydraulic transportation of thickened sludges[J].Water S A,2004,30(5):614-616.
[2]朱敏.污水处理厂污泥管道输送系统设计与研究[J].给水排水,2012,38(增刊):22-25.
[3]Markis F,Baudez J C,Parthasarathy R,et al.The apparent viscosity and yield stress of mixtures of primary and secondary sludge:Impact of volume fraction of secondary sludge and total solids concentration[J].Chem Eng J,2016,288:577-587.
[4]Baudez J C.Physical aging and thixotropy in sludge rheology[J].Applied Rheology,2008,18(1):13459-13466.
[5]Baudez J C,Markis F,Eshtiaghi N,et al.The rheological behaviour of anaerobic digested sludge[J].Water Res,2011,45(17):5675-5680.
[6]Tixier N,Guibaud G,Baudu M,et al.Determination of some rheological parameters for the characterization of activated sludge[J].Bioresour Technol,2003,90(2):215-220.
[7]Eshtiaghi N,Markis F,Slatter P.The laminar/turbulent transition in a sludge pipeline[J].Water Sci Technol,2012,65(4):697-702.
[8]Baudez J C,Gupta R K,Eshtiaghi N,et al.The viscoelastic behaviour of raw and anaerobic digested sludge:strong similarities with soft-glassy materials[J].Water Res,2013,47(1):173-180.
[9]Yang F,Bick A,Shandalov S,et al.Yield stress and rheological characteristics of activated sludge in an airlift membrane bioreactor[J].J Membr Sci,2009,334(1/2):83-90.
[10]刘弦.城市污水处理厂污泥管道输送阻力特性研究[D].重庆:重庆大学,2007.
[11]Mika L.Rheological behaviour of low fraction ice slurry in pipes and pressure loss in pipe sudden contractions and expansions[J].International Journal of Refrigeration,2012,35(6):1697-1708.
[12]Slatter P.The hydraulic transportation of thickened sludges[J].Water S A,2004,30(5):614-616.