农业废弃物制备生物质炭对奶牛养殖废水中氨氮吸附行为研究

The Adsorption Behavior Research of the Biochar Based on Agricultural Waste Matter and Ammonia Nitrogen from Dairy Waste Water

将玉米秸秆、花生壳、瓜子壳经高温炭化并活化后制成生物质炭,以奶牛养殖废水UASB反应器出水中的氨氮为吸附质,研究不同生物质炭对氨氮吸附动力学机理探讨。通过对动力学数据进行分析,根据相关系数R2比较发现准二级动力学方程比准一级动力学方程能更好的拟合动力学数据。Weber-Morris扩散模型拟合结果发现三种生物质炭对氨氮的吸附包括表面吸附和颗粒内扩散两个过程。吸附等温线拟合发现Freundlich方程R2分别为0.987,0.991,0.990能很好的描述生物质炭对氨氮的吸附过程。而Langmuir方程被证实不适合模拟研究中三种生物质炭对氨氮的吸附。花生炭被证实吸附量和吸附速率均大于玉米秸秆炭和瓜子炭。

The biochar was made from maize straw,peanut shell,sunflower seeds shell through high temperature carbonization.The adsorption mechanism of ammonia nitrogen in the biogas slurry with different biomass carbon was studied in this paper. Through the analysis of dynamic data,according to the correlation coefficient R2,the pseudo-second-order kinetics equation was better dynamic data fitting than the pseudo-first-order kinetics equation. The results from Weber - Morris diffusion model found adsorption of ammonia nitrogen in three kinds of biochar including two processes：surface adsorption and diffusion in the granules. Freundlich equation R^2 were 0.987,0.991,0.990of adsorption isotherm which were found the better description the process of biochar adsorption ammonia nitrogen than the Langmuir model. The Langmuir equation was proved not suitable for simulation three kinds of biochar adsorption of ammonia nitrogen in this study. The peanut shell biochar was proved that adsorption capacity and adsorption rate were greater than maize straw biochar and sunflower seeds biochar.