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毕业论文-飞灰中二恶英的低温药剂脱氯技术研究，共65页，22696字
摘要
垃圾焚烧飞灰中富集了垃圾焚烧产生的大部分二恶英类物质，是飞灰处理
处置过程中不能回避的重要问题。分解飞灰中的二恶英常用的方法包括熔融法、
高温焚烧法、超临界水氧化分解以及低温药剂还原法等，本文探索了用次亚磷
酸氢钠还原分解飞灰中的二恶英的低温药剂还原法。
本论文所有实验均在惰性气氛、200~500℃温度条件下进行，反应条件由自
行改造的耐压加热釜控制，分别采用 EROD(7-乙氧基-异吩恶唑酮-脱乙基酶活力
诱导法)和 HRGC—MS(高分辨率色谱质谱连用)检测二恶英。
实验证明二恶英去除率最高的实验操作方法为：150℃前通氮气使反应器为
还原气氛，然后密闭反应器，升温至设定值并保持 1h，进行脱氯还原反应，之
后继续通氮气 0.5h，再密闭反应器，待反应器降温至 100℃后取出处理过的飞灰。
本研究考察了温度对二恶英分解破坏的影响。采用 EROD 生物监测实验表
明，飞灰中二恶英的去除率随着温度的升高而升高。在 300℃时，次亚磷酸氢钠
发生热分解，此时二恶英去除率有较大提高；当温度升高到 350℃后去除率增加
趋势不明显。HRGC－MS 分析结果显示，当次亚磷酸氢钠添加量为 10%(质量
比)、反应温度分别为 350℃和 450℃时，飞灰中二恶英去除率分别为 99.4%和99.3%。
关键词：二恶英 飞灰 低温处理 次亚磷酸氢钠

ABSTRACT
Many tons of fly ash from municipal solid waste incinerators (MSWI) all over
the world cause environmental concern because of the dioxin-like compounds and
heavy metals they contain. At present there are several appropriate methods to
destruct dioxins: melting, burning, supercritical water oxidation and low-temperature
chemical reduction. This study investigates the dechlorination of MSWI fly ash
during low-temperature chemical reduction process with sodium hypo phosphite as
dechlorinating agent.
In this study, all the MSWI fly ash samples were treated in an ameliorated
high-temperature reaction vessel at a temperature between 200℃ and 500℃ under
oxygen-deficient conditions. A traditional chemical analysis method (HRGC-MS)
and a cell-based bioassay (EROD) were conbined to evaluate the amounts of dioxin
in MSWI fly ash.
The best decontamination efficiency was obtained from a procedure as follow:
put the untreated fly ash into the reactor, inject N2 gas until the inner temperature of
the reactor is heated to 150℃, then seal the reactor and raise the temperature to a
certain value which is maintained for 1h; after that, inject N2 gas for another 0.5h,
take out the treated fly ash after the temperature has dropped to below 100℃.
This study describes the effect of temperature on the dechloridation of dioxins in
MSWI fly ash. It was shown in this study by biomass analysis that, the dechloridation
efficiency was higher at a higher temperature. When the temperature reached 300℃
there was a notable efficiency increase, and when the temperature was higher than
350℃ the increase rate slowed down. The treatment efficiency, as measured by
chemical analysis, was 99.4% (350℃, 10% (mass) Na2PH2O2) and 99.3% (450℃,
10% (mass) Na2PH2O2).
Key word：dioxin; fly ash; low-temperature treatment; sodium hypo phosphite

目录
摘要 .......1
ABSTRACT.....II
目录.III
第 1 章
综述 ...1
1.1 飞灰中二恶英类物质处理技术研究的重要性........1
1.2 飞灰中二恶英类物质处理处置技术4
1.3 低温药剂还原法的特点和研究进展5
1.4 二恶英类物质检测手段的介绍........8
1.4.1 色谱法.9
1.4.2 生物法.9
1.5 飞灰中二恶英类物质评价方法......11
1.6 研究目的和技术路线..........11
第 2 章 低温药剂还原法处理飞灰中二恶英实验研究 .........13
2.1 研究内容......13
2.2 实验方法确定..........13
2.2.1 实验装置的设计.......14
2.2.2 实验操作方法的确定...........17
2.3 分析测试方法确定..18
2.4 实验方案......20
第 3 章 实验结果及讨论 .........22
3.1 最佳操作方法确定..22
3.2 温度对飞灰中二恶英去除率的影响..........24
3.3 HRGC-MS法测定二恶英去除率 ....27
第 4 章 结论与建议 .....33
4.1 结论..33
4.2 建议..33
参考文献.........34
致谢.36
声明.36
附件 1 EROD实验步骤.......37
附件 2
文献翻译......39