城市固废的热—固—液—气—化—生耦合模型

发布时间：2018-06-01 09:39

  本文选题：城市固废 + 生化降解　； 参考：《浙江大学》2017年硕士论文

【摘要】：我国城市固废以快速易降解的厨余组分为主,渗滤液产量大,容易引起填埋体水位过高,甚至使固废堆体达到饱和状态。集中填埋后的城市固废因降解产生固相质量损失,渗滤液中过高的VFA会影响生化降解的进行,液气运移过程、生化反应会造成堆体内部能量的迁移,因此城市固体废弃物堆体在生化降解趋于稳定化的过程中处于多场耦合相互作用的状态。通过建立THMCB多场耦合模型研究了城市固体废弃物堆体内的多场耦合作用,推导了多场耦合骨架位移、液气运移、能量平衡、生化反应以及溶质迁移的控制方程,重点模拟了温度对城市固废中生化降解过程的影响。THMCB多场耦合模型包含了生化降解的二阶段厌氧模型与好氧降解模型,可在严格厌氧、好氧、兼性环境下对城市固体废弃物生化降解过程进行模拟,氧气浓度为控制变量,当氧气浓度高于10%时,以好氧降解为主,氧气浓度低于10%时以厌氧降解为主。对已有的生化降解反应速率一级动力方程进行了修正,在水解反应、甲烷化反应、甲烷菌衰亡反应的一级动力学方程中加入温度影响函数。基于OGS软件,通过数值计算分析了温度对城市固废中纤维素、总糖、蛋白质和脂肪组分的厌氧降解过程的影响,并研究了不同温度下的水解与甲烷化过程,研究结果表明,在10-45℃温度范围内,温度会显著影响水解与甲烷化进程的反应速率。将大型模型槽试验数据与数值计算结果进行对比,揭示了温度在多场耦合作用中的影响。在填埋初期采用好氧降解模型进行了初步计算,模拟了填埋初期堆体内的好氧降解过程导致的堆体内温度变化,模拟结果与模型槽试验结果在填埋初期(1-20d)温度上升趋势保持高度一致。
[Abstract]:Urban solid waste in China is dominated by fast and easily degradable kitchen waste components. The leachate output is large, which can easily cause the water level of landfill to be too high, and even make the solid waste reactor reach saturation state. The mass loss of solid phase is caused by the degradation of municipal solid waste after concentrated landfill. The excessive VFA in leachate will affect the biodegradation, and the process of liquid gas migration and biochemical reaction will result in the transfer of energy in the body of the reactor. Therefore, the municipal solid waste reactor is in the state of multi-field coupling interaction in the process of biodegradation stabilization. The multi-field coupling in municipal solid waste reactor (MSW) was studied by establishing THMCB multi-field coupling model, and the governing equations of multi-field coupling skeleton displacement, liquid-gas transport, energy balance, biochemical reaction and solute transport were derived. The effect of temperature on the biodegradation process in municipal solid waste was simulated emphatically. THMCB multi-field coupling model included two-stage anaerobic model and aerobic degradation model of biochemical degradation, which could be used in strict anaerobic and aerobic processes. The biodegradation process of municipal solid waste was simulated in facultative environment. Oxygen concentration was the control variable. When oxygen concentration was higher than 10, aerobic degradation was dominant, and anaerobic degradation was the main factor when oxygen concentration was lower than 10. The first order kinetic equation of biodegradation rate was modified by adding the temperature effect function into the first-order kinetic equations of hydrolysis methanation and methanogen decay. Based on OGS software, the effects of temperature on the anaerobic degradation of cellulose, total sugar, protein and fat components in municipal solid waste were analyzed by numerical calculation. The hydrolysis and methanation processes at different temperatures were studied. In the temperature range of 10-45 鈩，

本文编号：1963723