城市污泥与微藻共水热液化水相产物特性分析

Characterization of Aqueous Phase Products of Co-Hydrothermal Liquefaction of Municipal Sludge with Microalgae

城市污泥作为一种城市化进程中的废料,对城市发展、环境保护和资源再利用是一种新挑战。城市污泥与微藻共处理可以改善生物燃料的理化性质,提高处理过程的能源效率。开展了城市污泥和微藻共水热液化实验,通过调控反应温度、反应时间、生物质/水比率和污泥/生物质比率操作参数探究水相产物特性化学需氧量、总氮、氨氮的变化情况。结果表明,响应面对水相化学需氧量、总氮、氨氮特性均有较好的拟合效果,四个操作参数中生物质/水比率和污泥/生物质比率对水相特性的影响最大。且在反应温度为341.44℃,反应时间为37.81 min,生物质/水比率为0.08 g/mL和污泥/生物质比率为0.653时,可以获得化学需氧量、总氮、氨氮含量最低的水相。

Municipal sludge(MS),as a waste product of urbanization,is a new challenge for urban development,environmental protection,and resource reuse.Co-processing of MS with microalgae can improve the physicochemical properties of biofuels and increase energy efficiency.In this paper,a co-hydrothermal liquefaction experiment of MS and microalgae was carried out to investigate the trends of the aqueous phase product properties,including chemical oxygen demand,total nitrogen,and ammonia nitrogen by regulating the reaction temperature,reaction time,biomass/water ratio,and sludge/biomass ratio.The best hydrothermal reaction conditions were simulated and optimized by determining the physicochemical properties of the aqueous phase.The results show that the response surface model fits for the characteristics of chemical oxygen demand,total nitrogen,and ammonia nitrogen in the aqueous phase.Among the four operational parameters,the biomass/water ratio and sludge/biomass ratio have the greatest impact on the aqueous phase characteristics.Specifically,at a reaction temperature of 341.44℃,a reaction time of 37.81 min,biomass/water ratio of 0.08 g/mL,and sludge/biomass ratio of 0.653,the lowest levels of chemical oxygen demand,total nitrogen,and ammonia nitrogen content in the aqueous phase can be achieved.