The main objective of this study was to develop generalized first-order kinetic models to represent hydrothermal decomposition and oxidation of biosolids within a wide range of temperatures (200-450℃). A lumping approach was used in which oxidation of the various organic ingredients was characterized by the chemical oxygen demand (COD), and decomposition was characterized by the paniculate (i.e., nonfilterable) chemical oxygen demand (PCOD). Using the Arrhenius equation (k = k{sub}e{sup}((-E{sub}a)/RT) activation energy (E{sub}a) levels were derived from 42 continuous-flow hydrothermal treatment experiments conducted at temperatures in the range of 200-450℃. Using predetermined values for k{sub}0 in the Arrhenius equation, the activation energies of the various organic ingredients were separated into 42 values for oxidation and a similar number for decomposition. The activation energy values were then classified into levels representing the relative ease at which the organic ingredients of the biosolids were oxidized or decomposed. The resulting simple first-order kinetic models adequately represented, within the experimental data range, hydrothermal decomposition of the organic particles as measured by PCOD and oxidation of the organic content as measured by COD. The modeling approach presented in the paper provide a simple and general framework suitable for assessing the relative reaction rates of the various organic ingredients of biosolids.
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机译:这项研究的主要目的是建立广义的一阶动力学模型,以表示水热分解和生物固体在广泛温度范围(200-450℃)中的氧化。使用集总方法,其中各种有机成分的氧化以化学需氧量(COD)为特征,分解以颗粒状(即不可过滤的)化学需氧量(PCOD)为特征。使用Arrhenius方程(k = k {sub} e {sup}((-E {sub} a)/ RT)},活化能(E {sub} a)的水平来自在温度下进行的42次连续流水热处理实验在200-450℃范围内,使用Arrhenius方程中k {sub} 0的预定值,将各种有机成分的活化能分为42个氧化值和相似的分解值。然后将其分类为代表生物固体中有机成分被氧化或分解的相对难易程度的水平,由此产生的简单的一阶动力学模型在实验数据范围内足以表示通过PCOD和氧化法测量的有机颗粒的水热分解。本文介绍的建模方法提供了一个简单而通用的框架,适用于评估各种有机化合物的相对反应速率生物固体成分。
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