河道受污染底泥免烧结固化和稳定化的实验研究

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河道受污染底泥免烧结固化

和稳定化的实验研究

摘要

河道底泥来源广泛，与水体环境密切相关受到越来越多的关注。目前多数以

河道疏浚方式等物理方式清理河道底泥，疏浚后的底泥堆放或填埋处理，导致

了底泥污染物容易随雨水浸出污染地表水或地下水，同时也导致底泥中大量的

矿物资源浪费。并且由于其处理数量庞大，内部成分复杂，污染物种类和含量较

多等因素，受污染河道底泥的资源化利用成为了现今广泛关注的问题。

传统的物理、化学、生物处理底泥都具有一定的优势，但是其局限性也是显

而易见的。因此，本研究建立在以往的研究的基础上，选用水泥、天然斜发沸石

氧化钙和 TMT 作为固化剂和稳定剂对蕰藻浜污染严重河道进行固化和稳定化实

验研究，确定了混合固化剂最优配比，制得的固化试件具有优良的抗压性能和

较低浸出毒性，并且对固化、稳定化机理和原因进行了分析总结。主要研究结论

如下：

（1）根据蕰藻中下游底泥环境风险评价结果得出：江杨北路桥、淞港码头、

泰和路、陈行桥等部分地区附近河段重金属污染程度较严重，主要超标污染物为

Zn 和Cu，生态风险最高的重金属为 Cd。在资源化过程中，需对这三种重金属

加强控制。

（2）通过正交实验和单因素确定了固化剂最优配比，即水泥、天然斜发沸

石、氧化钙的质量比为 31.3 : 15.7 : 3 : 0，并且，从水化反应、火山灰反应、微集

料作用、离子交换作用和碳酸化作用及相互间协同作用等方面分析，研究并探讨

了固化剂的固化机理。

（3）在固化配比基础上，以浸出液的 pH 值、CODCr、NH3-N、重金属浓度为

指标，完善了固化和稳定化最优配比，即 m（水泥）：m（天然斜发沸石）：

m（氧化钙）：m（TMT）=30 :12.5 :3 :1.5。对稳定剂的稳定化原因、机理进行了

探究，发现沸石对 NH3-N 和重金属吸附属于 Langmuir 吸附等温模型规律，且

吸附量为。原底泥中 Cr、Cu、Zn、Mn 主要以残

渣态存在， Pb 和Cd 主要以还原态存在， Ni 主要是有机态。稳定化后，

Cr、Cd、Pb 等七种重金属不稳定态（弱酸态和还原态）含量处于总量的 1.3%至

8.9%，残渣态成为重金属稳定化后的主要形态。

（4）在模拟的较为极端自然环境中，最优配比具有较好的耐酸性、稳定性

和适用性，还可根据实际工程需要调节用量，以满足不同的标准规定和要求。最

终，固化和稳定化处理的底泥，可用于垃圾填埋、道路填方、农用、水处理材料

及制水泥砖（路面、护坡、户外装饰）的应用等方面。

关键词：河道底泥　固化　稳定化　最优配比　TMT　浸出毒性

ABSTRACT

Nowadays, there has been a growing attention on river sediments as a result of

its various sources and close relationship to the water environment. Treatments of

such contaminated sediments are usually massive. Current treatment of these

sediments are usually river dredging and other physical methods followed by landfill

disposition. Leaching from the dredged sediment may lead to contamination of both

surface and underground water. On the other hand, such method also led to a large

amount of waste of mineral resources. Moreover, because of the complexity of

sediment components as well as the large amount and various types of pollutants,

proper usage of the contaminated sediment has become a worldwide concern.

It is obvious that traditional treatments of contaminated sediments using

physical, chemical and biological method are limited in various ways, though there

are also certain advantages. This study, developed from previous research, used

cement, natural zeolite, calcium oxide and TMT as a curing agent and stabilizer for

sediments contaminated from the river of Wen Zao Bang to create a new

environmental material by determining the optimal ratio of these agents. The curing

specimens were both with excellent compression performance as well as low toxicity

in leaching. Mechanism of solidification and stabilization were examined, discussed

and summarized. The main finds are as follows:

Environmental risk assessment shows that the following areas were seriously

polluted by heavy metals: North Jiang Yang Bridge, Song Gang port, Taihe Road,

Chen Hang bridges. The major pollutants were Zn and Cu. However, ecological risk

assessment also indicates that Cd was at the highest. Therefore, controls most be taken

for these three heavy metals in the process.

The optimal ratio of curing agents including cement, natural clinoptilolite,

calcium oxide was determined as 31.3: 15.7: 3: 0 (mass ratio), by carrying out an

orthogonal experiment and single factor analysis. Mechanism of solidification was

explored in aspects of: 1) hydration reaction, 2) pozzolanic reaction, 3) micro-set

material effect, 4) ion exchange and carbonation and 5) mutual synergies.

Based on the ratio of solidification, the optimal ratio of the agents for

solidification and stabilization was further optimized by analyzing: 1) pH of the

leaching solution, 2) CODCr, 3) NH3-N, 4) index of heavy metal concentration. The

final mass ratio was: cement: clinoptilolite: calcium oxide: TMT = 30: 12.5: 3:

1.5.The underlying mechanism for the stabilization was also investigated: adsorption

of NH3-N and heavy metals on zeolite could be fitted in Langmuir adsorption

isotherm model, and the adsorption capacity was .

Chromium, Cu, Zn and Mn in pure river sediments were mainly in residual fraction,

while Pb and Cd existed mainly in the reducible fraction and Ni was mainly in

organic state. After stabilization, the proportion of heavy metals in the two more

reactive fraction (weak acid extractable and reducible fraction) reduced to the range

from 1.3 to 8.9% of the total, and the residual fraction became to be the main form.

In a simulated experiment of more extreme environments, the material with the

optimal ratio of the agents has proved to have good acid resistance, stability and

applicability. It was also capable to be adjusted to the suitable amount for practical

project, in order to meet different standards and requirements. In conclusion, after

solidification and stabilization, such contaminated sediments of can be used as

land/road fill material, agricultural soil, water treatment materials and cement bricks

(for pavement, slope, outdoor decoration) in different applications.

Key Words：River sediment，solidification，stabilization，optimal

proportion，TMT，leaching toxicity

目  录
中文摘要
Abstract
第一章 绪  论.................................................................................................................1
1 研究背景..............................................................................................................1
1.1 课题来源.......................................................................................................1
1.2 河道底泥组成及污染现状...........................................................................1
1.3 河道底泥污染种类及特点...........................................................................3
2 河道底泥处理、处置及利用..............................................................................5
2.1 生物处理.......................................................................................................5
2.2 制备环保材料...............................................................................................6
2.3 淋洗和萃取...................................................................................................7
2.4 免烧结固化...................................................................................................7
2.5 螯合稳定化...................................................................................................8
3 研究内容和技术路线..........................................................................................8
第二章 蕰藻浜底泥污染检测及重金属污染风险评价.............................................11
1 实验部分............................................................................................................12
1.1 底泥样品采集.............................................................................................12
1.2 实验材料和设备仪器.................................................................................13
1.2 样品预处理和分析实验.............................................................................14
2 底泥重金属的含量及分布情况........................................................................14
2.1 底泥重金属含量基本情况.........................................................................14
2.2 重金属含量沿河分布情况.........................................................................16
3 分析方法和评价................................................................................................18
3.1 地累积指数法.............................................................................................18
3.2 潜在生态危害指数法.................................................................................20
3.3 内梅罗综合指数法.....................................................................................22
4 本章小结............................................................................................................24
第三章 蕰藻浜受污染河道底泥固化的实验研究.....................................................26
1 实验部分............................................................................................................26
1.1 实验材料和设备仪器.................................................................................26
4

1.2 河道底泥正交固化实验.............................................................................28
1.3 河道底泥单因素固化实验.........................................................................29
1.4 最优配比的筛选方法和评判指标.............................................................30
2 正交实验结果和分析........................................................................................31
3 单因素实验结果和分析....................................................................................35
3.1 水泥最佳添加量的结果及分析.................................................................35
3.2 水泥固化河道底泥机理.............................................................................36
3.3 沸石最佳添加量的结果及分析.................................................................37
3.4 沸石固化河道底泥机理.............................................................................39
3.5 氧化钙最佳添加量的结果及分析.............................................................40
3.6 氧化钙固化河道底泥机理.........................................................................42
3.7 TMT 添加量对抗压强度的影响................................................................43
3.8 TMT 对抗压强度削弱的原因....................................................................44
4 本章小结............................................................................................................44
第四章 河道底泥无害化及稳定化研究.....................................................................45
1 实验部分............................................................................................................46
1.1 实验材料和设备仪器.................................................................................46
1.2 受污染底泥稳定化处理方法.....................................................................47
1.3 重金属和有机污染物浸出实验.................................................................48
1.4 天然斜发沸石静态吸附实验.....................................................................49
1.5 重金属形态分析实验.................................................................................49
1.6 稳定化效果的评判指标和标准.................................................................50
2 强碱性物质浸出和有机物稳定化的结果和分析............................................51
2.1 浸出液 pH 值的变化情况...........................................................................51
2.2 CODCr 的稳定化效果和分析......................................................................53
2.3 NH3-N 的稳定化效果和分析.....................................................................55
3 重金属稳定化结果和分析................................................................................57
3.1 底泥重金属浸出状况.................................................................................57
3.2 水泥稳定化重金属的结果和分析.............................................................57
3.3 天然斜发沸石稳定重金属的结果和分析.................................................61
3.4 氧化钙稳定重金属的结果和分析.............................................................64
3.5 TMT 稳定重金属的结果和分析................................................................65

4 重金属浸出形态分析结果................................................................................66
4.1 Cr 形态分析.................................................................................................66
4.2 Cd 形态分析................................................................................................67
4.3 Pb 形态分析................................................................................................67
4.4 Ni 形态分析.................................................................................................68
4.5 Cu 形态分析................................................................................................68
4.6 Zn 形态分析................................................................................................69
4.7 Mn 形态分析...............................................................................................70
5 本章小结............................................................................................................70
第五章 底泥固化和稳定化受理化因素的影响研究.................................................72
1 固化效果受理化因素的影响及分析................................................................72
1.1 底泥粒径对固化效果的影响.....................................................................72
1.2 混合固化剂含量对固化效果的影响.........................................................73
1.3 水灰比对固化效果的影响.........................................................................75
1.4 有机物含量对固化效果的影响.................................................................76
2 稳定化效果受理化因素的影响及分析............................................................77
2.1 浸提剂pH 值变化对稳定化的影响...........................................................77
2.2 振荡时间对稳定化的影响.........................................................................78
2.3 底泥污染物含量对稳定化的影响.............................................................79
2.4 水灰比对稳定化的影响.............................................................................80
3 本章小结............................................................................................................81
第六章 结论.................................................................................................................82
参考文献......................................................................................................................84
6

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摘要：

河道受污染底泥免烧结固化和稳定化的实验研究摘要河道底泥来源广泛，与水体环境密切相关受到越来越多的关注。目前多数以河道疏浚方式等物理方式清理河道底泥，疏浚后的底泥堆放或填埋处理，导致了底泥污染物容易随雨水浸出污染地表水或地下水，同时也导致底泥中大量的矿物资源浪费。并且由于其处理数量庞大，内部成分复杂，污染物种类和含量较多等因素，受污染河道底泥的资源化利用成为了现今广泛关注的问题。传统的物理、化学、生物处理底泥都具有一定的优势，但是其局限性也是显而易见的。因此，本研究建立在以往的研究的基础上，选用水泥、天然斜发沸石氧化钙和TMT作为固化剂和稳定剂对蕰藻浜污染严重河道进行固化和稳定化实验研究，确定了...

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