【作者】 翟云波；

【导师】 魏先勋； 曾光明；

【作者基本信息】 湖南大学 ， 环境工程， 2005， 博士

【摘要】 本文以城市污水生物法处理产生的剩余污泥为原料,针对传统污泥资源化利用过程中的缺点与弊端,采用化学活化方法对城市污水厂剩余污泥进行热解来获得多孔含炭吸附材料,对其制备过程中的相关问题进行了研究,将产生的污泥衍生多孔吸附材料应用到有害气体及废水的处理中,并对应用过程中的有关条件进行了详细研究,开拓出污泥资源化利用的又一新工艺。 化学活化方法制备污泥衍生吸附材料中,化学活化药剂的选取是制备多孔吸附材料的关键因素。在磷酸、硫酸、ZnCl₂及KOH四种活化药剂中,通过S_BET面积、碘的吸附量和亚甲基兰吸附量作为衡量活化药剂性能的因素。实验结果表明,无论从S_BET面积还是碘的吸附量以及亚甲基兰的吸附量,都可以看出,磷酸和ZnCl₂作为活化药剂产生的污泥衍生吸附材料性能都明显的好于硫酸和KOH;然后结合磷酸和ZnCl₂作为活化药剂的优缺点,最终确定采用ZnCl₂作为活化药剂。然后,利用正交实验和单因素实验研究了ZnCl₂作为活化药剂产生污泥衍生多孔吸附材料的有关影响因素,包括热解温度、热解停留时间及活化药剂的浓度。证明了活化药剂浓度为3mol/L、热解温度850℃及停留时间60min是最适宜制备污泥衍生多孔吸附材料的。并利用中心复合设计研究了热解停留时间和热解温度对吸附材料的特性参数的影响,证明了正交实验的正确性。活化药剂在污泥制备多孔吸附材料中的作用也通过热重分析进行了研究,研究结果表明,氯化锌对污泥原料中的有机质起润胀、胶溶以至溶解的作用。药液渗透到原料的内部,溶解有机质成分而形成孔隙,使原料中的氢、氧原子以水的形式分离出来,使更多的碳保留在原料中,提高了多孔吸附材料的产率。 利用热分析仪研究了单纯污泥及经过ZnCl₂活化的污泥在氮气气氛下的热解特性,并结合FTIR光谱对不同阶段的逸出气体进行了研究,实验发现,单纯污泥的热解有明显的3阶段反应,而ZnCl₂活化的污泥热解存在明显的4阶段反应,其各个阶段产生逸出气体是不同的。并对污泥热解反应的机理进行了研究,同时利用微分法对污泥热解反应的机理函数进行了求解。 材料的有关特性参数对材料的吸附性能有很大的影响。对污泥衍生材料的特性的进一步研究,发现材料无论从外观,形貌及表面酸碱特性都发生了很大的变化,这些参数的变化与热解温度有很大的关系,低温时材料的表面呈酸性,而高温时产生的材料表面呈碱性。另外,通过氮气的吸附可以证明污泥衍生材料的孔隙特性与热解温度、热解停留时间及活化药剂的浓度有很大的关系。通过孔径分更多还原

【Abstract】 The residual sewage sludge produced through biologic method treatment domestic sewage is taken as raw material, based on the disadvantages of all kinds of traditional sewage sludge treatment, the chemical activation method is applied to paralysis sewage sludge to obtain porous adsorption materials. The correlative problems during the preparation are worked out. And then, the adsorbent derived from sewage sludge is applied to the sulfur dioxide and metal ions treatment process, and the concerned conditions are worked out during the applications, and developed a new process for sewage sludge resource application.The key factor is the selection of the chemical activation reagent during the adsorbent preparation through the chemical activation method. The activation reagent is selected among the Phosphoric acid, Sulphuric acid, Chloride Zinc and Potassium hydroxide, and Sbet, iodine adsorption value and methylene blue adsorption value are taken as the factors to reflect the activation reagent performance, the experimental results show that the effect of the phosphoric acid and Chloride Zinc on materials performances as activation reagent is favourable than sulphuric acid and potassium hydroxide, whether Sbet and iodine adsorption value or methylene blue adsorption value. Where after, combined with other advantages and disadvantages between the phosphoric acid and Chloride Zinc activation, the Chloride Zinc is selected as activation reagent finally. And utilized the orthogonal experiment and single factor experiment to research correlative effect factors of produced porous adsorbent derived from sewage sludge. When ZnCl2 is taken as activation reagent, effect factors include pyrolysis temperature, pyrolysis dwell time and the concentration of activation reagent. The experimental results show that the most feasible conditions to produced adsorbents is the concentration of activation reagent 3mol/L, pyrolysis temperature 850 ℃ and the pyrolysis dwell time 60 min. And utilized center complex design to research the effect of pyrolysis temperature and pyrolysis dwell time on the characteristics of adsorbent derived from sewage sludge, the simulation experimental results show that the correctness of the orthogonal experiment. And then, the function of the activation reagent ZnCl2 is worked out through thermal analysis apparatus, theexperimental result shows that the function of ZnCl2 is to accelerate the organic component of the sewage sludge wetness and swell, mucus dissolve and dissolution, the reagent solution penetrates to the interior of the sewage sludge and dissolves organic components to produce small opening, and the reagent ZnCl2 can promote the H and O atom production and be separated to become H2O, so more C can be reserved in the sewage sludge to increase the yield of the adsorbent.The thermal analysis apparatus was utilized to study the pyrolysis characteristics of the sewage sludge with ZnCb activation sewage sludge and without ZnCh activation sewage sludge under N2 atmosphere, and combined with FTIR spectrum to research produced gases in all kinds of stages, the experimental results show that the three stages pyrolysis reactions appeared for sewage sludge pyrolysis without ZnCl2 activation, but the four stages pyrolysis reaction appeared for ZnCb activation sewage sludge, and then the pyrolysis mechanism were studied through combined FTIR, simultaneity, the differential coefficient method was applied to question the reaction mechanism functions.The performances of the adsorbent derived from sewage sludge through chemical activation method are mainly affected by the characteristic parameters of the adsorbent including the appearance, shape and the acidic and basic characteristic change and so on. So the keys of the next research are the analysis of characteristic parameters. The experiment shows that the appearance, shape and the acidic and basic characteristics change obviously when pyrolysis temperature changed, these parameters relate to pyrolysis temperature, when the temperature is low, the acidic groups are favorite, and when the pyrolysis temperature is high, the basic groups are favorite. The porous characteristics of adsorbent derived from sewage sludge can be represented through N2 adsorption isotherm, and the porous characteristics are related to pyrolysis temperature, pyrolysis dwell time and the concentration of activation reagent. According to pore diameter distributing curve, it can be obtained that the pore diameter of adsorbent derived from sewage sludge is mainly mesporous. And utilized related apparatus to measure adsorbent density, it is found that the true density is 2.8 g/cm3, the Sbet area is 347 m2/g, the total porous volume is 0.289 cmVg and 0.312cm3/g before and after through hydrochloric acid rinse, respectively, and the microporous volume is 0.0876 cm / g and 0.098 cm3 / g, respectively, before and after through hydrochloric acid rinse, and更多还原