污水污泥厌氧消化沼渣协同园林绿化垃圾热解工艺条件优化研究

Study on Optimization of Process Conditions for Co-Pyrolysis of Biogas Residue from Anaerobic Digestion of Sewage Sludge and Landscaping Waste

摘要:

为实现污水污泥厌氧消化沼渣与园林绿化垃圾的协同资源化利用，以双酚A（BPA）去除率为评价指标，采用响应面法优化沼渣和园林绿化垃圾协同热解制备生物炭的工艺条件，并开展协同热解生物炭吸附机制分析。结果显示，协同热解因素对BPA去除率的影响按顺序由高到低排列为热解温度、升温速率、热解时间；模拟所得最优工艺条件为热解温度700 ℃、升温速率5 ℃/min、热解时间为1 h，可实现对BPA吸附去除率为64.8%。协同热解生物炭吸附去除BPA的过程符合准二级动力学模型，为化学吸附过程；吸附等温线可由Freundlich等温方程模拟，属于吸热反应，温度升高有利于提高BPA吸附去除率。相关结论可为城镇多源有机固废协同热解制备高效吸附剂提供技术解析和工艺参数支撑。

Abstract:

To realize the synergistic resource utilization of biogas residue from anaerobic digestion of sewage sludge and landscaping waste, taking the removal rate of bisphenol A (BPA) as the evaluation index, the response surface method is adopted to optimize the process conditions for the co-pyrolysis of biogas residue and landscaping waste to prepare biochar, and the adsorption mechanism of the co-pyrolysis biochar is analyzed. The results show that the effects of co-pyrolysis factors on the removal rate of BPA are ranked from high to low as pyrolysis temperature, heating rate and pyrolysis time. The optimal process conditions simulated are pyrolysis temperature of 700 ℃, heating rate of 5 ℃/min and pyrolysis time of 1 h. The adsorption removal rate of BPA can be achieved at 64.8%. The process of removing BPA by co-pyrolysis biochar adsorption conforms to the quasi-second-order kinetic model and is a chemical adsorption process. The adsorption isotherm can be simulated by the Freundlich isotherm equation, which belongs to an endothermic reaction, and an increase in temperature is conducive to improving the adsorption removal rate of BPA. The relevant conclusions can provide technical analysis and process parameter support for the co-pyrolysis of multi-source organic solid waste in urban areas to prepare efficient adsorbents.