PDF《南京林业大学 本科毕业设计（论文）》

南京林业大学 本科毕业设计(论文) 题目:城市污泥的 DME 深度脱水技术 研究 学院: 南方学院 专业: 给水排水工程 学号: n080605110 学生姓名: 蒋昱煜 指导教师: 林子增 二零一二年五月三十日 I 城市污泥的 DME 深度脱水技术研究 摘要随着污水处理厂在我国各大城市的普及, 污水处理的伴生物污泥的处理处置 越来越引起人们的关注.

污水处理厂产生的大量剩余污泥含水率很高,为了减少 污泥体积,降低运输费用,利于后续处理,必须对其进行脱水处理. DME 是一种有机溶剂,在常温常压下以气体形式存在,并能溶解有机物质 和部分水,而且,在室温和适度的压力下(0.6-0.8MPa) ,DME 可以被液化.液化DME 可以有效地用于污泥脱水,并且它可以从提取物中回收并且容易重复使 用. 本文以南京江心洲污水处理厂的污泥为样品,进行了污泥的 DME 深度脱水 实验.在污泥 DME 脱水实验中,本文详细考察了脱水时间以及液化 DME 和污 泥的比例(以下简称液固比)对污泥脱水的影响,实验结果表明,脱水时间越长, 液固比越大,污泥脱水效果越好,确定出最经济高效的脱水时间为 80min,考虑 到经济因素,确定最佳液固比为 120:1.本实验中污泥的脱水反应可以用一级反 应速率表示. 关键词:活性污泥 DME 脱水 含水率 II A STUDY ON THE DEHYDRATION OF SEWAGE SLUDGE BY USING DME Abstract As sewage treatment plant is becoming more and more popular in big cities of China, sewage treatment companion――Sludge Treatment and Disposal is drawing increasing concern. The water content of sludge which Sewage treatment plants produce is extremely high. The sludge must be dehydrated in order to reduce sludge volume, cut transport costs, and help follow-up treatment . DME is a kind of organic solvent in gas form at room temperature and pressure, and can dissolve organic matter and some water in liquid form. Moreover ,DME can be liquefied at room temperature and moderate pressure (0.6-0.8MPa). Therefore, liquefied DME can be effectively used for sludge dewatering and it can be recovered from the extract to reuse at the meantime. In this paper, the sludge from Nanjing Jiangxinzhou sludge wastewater treatment plant is used as samples in deep hydration experiment of sludge using DME. In the experiment ,this paper examines the impact of time and the ratio of liquefied DME and sludge (referred to as liquid-solid ratio hereinafter ) on sludge dewatering. The results show that the longer dehydration time is , the higher the liquid-solid ratio, the better sludge dewatering result will come out. The most cost-effective dewatering time is defined as 80min for the sake of saving time and taking economic factors into account , the optimum liquid-solid ratio is defined as 120:1 ml / g . In this study, the dehydration of the sludge can be expressed in pseudo-first order reaction rate. Key words: activated sludge,DME, dehydration ,moisture content III 目录

第一章? 绪论.1 1.1? 引言

1 1.2? 污泥的水分

2 1.2.1 表面吸附水

2 1.2.2 间隙水

3 1.2.3 毛细结合水

3 1.2.4 内部结合水

3 1.3? 污泥的危害

4 1.4? 污泥脱水技术

4 1.4.1? 污泥机械脱水

5 1.4.2? 污泥干化脱水

5 1.4.3? 污泥化学调质

6 1.4.4? 超声波污泥改性脱水

7 1.4.5? 污泥的水热改性法脱水

7 1.4.6? 冻融法

8 1.4.7?DME 的污泥深度脱水.8 1.4.8? 各种脱水方法比较

8 1.5? 污泥的处置

9 1.6? 本文的研究目的和主要研究内容