Fe<sup>2+</sup>-PDS调理-水平电场脱水工艺对疏浚底泥脱水性能的影响

朱书源; 王毅力

doi:10.12153/j.issn.1674-991X.20230045

Fe²⁺-PDS调理-水平电场脱水工艺对疏浚底泥脱水性能的影响

doi: 10.12153/j.issn.1674-991X.20230045

朱书源,
王毅力^,

北京林业大学环境科学与工程学院, 水体污染源控制技术北京市重点实验室

基金项目: 国家自然科学基金面上项目（51978054）

详细信息

作者简介:
朱书源（1998—），男，硕士研究生，主要从事污泥减量化研究，1352883860@qq.com

通讯作者:
王毅力（1972—），男，教授，研究方向为固体废物处理处置，wangyilimail@126.com

中图分类号: X703
计量
- 文章访问数: 101
- HTML全文浏览量: 42
- PDF下载量: 24
- 被引次数: 0
出版历程
- 收稿日期: 2023-01-16
- 网络出版日期: 2023-11-24

Effect of Fe²⁺-PDS conditioning-horizontal electro-dewatering process on dewatering performance of dredged sediment

ZHU Shuyuan,
WANG Yili^,

Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University

摘要

摘要:
针对高含水率疏浚底泥限制其后续处置的问题，应用Fe²⁺-过二硫酸盐（PDS）调理-水平电场脱水（HED）工艺处理底泥样品，研究响应曲面法对Fe²⁺-PDS调理-HED工艺操作参数（Fe²⁺及PDS的投加量、电压、通电时间）的优化，分析调理过程底泥形貌及性质的变化以及工艺各阶段（调理、重力沉降、电脱水）底泥水分及有机组分的沿程变化。结果表明：1）Fe²⁺和PDS调理底泥时，最佳投加量分别为4和10 mg/g（以TSS计），HED阶段最佳通电时间为80 min，最佳电压为45 V，在上述参数下，脱水底泥含水率由原泥的88.55%降至55.15%。2）在调理阶段，底泥结合水含量由0.44 g/g（以干固体计，全文同）降至0.28 g/g，胞外聚合物（EPS）中蛋白质和多糖总量增加，黏液层（Slime）中蛋白质类物质和可溶性微生物副产物荧光强度降低，紧密附着层（TB-EPS）中总荧光强度增至12.40×10⁷ AU·nm²；在HED阶段，电场作用导致底泥有机物的进一步释放从阴极流出，阴极区EPS各层中的可溶性微生物副产物荧光强度显著增加。3）调理过程产生的硫酸根自由基（SO₄ ⁻·）能够氧化破解底泥中的微生物细胞并将内含物释放至EPS中，同时改变底泥的水分分布与EPS组分特征，原位产生的Fe（Ⅲ）通过絮凝作用改变了底泥的絮体结构，从而有利于底泥脱水性能的提升。
- 疏浚底泥 /
- Fe²⁺-PDS调理 /
- 水平电场脱水 /
- 脱水性能 /
- 胞外聚合物(EPS)
Abstract:
Aiming at the problem of restricting the subsequent disposal of dredged sediment with high water content, Fe²⁺-perdisulfate (PDS) conditioning - horizontal electro-dewatering (HED) process was used to treat sediment samples. The operating parameters (Fe²⁺ and PDS dosage, voltage, power-on time) of Fe²⁺-PDS conditioning - HED process were optimized through the response surface method (RSM), and the variations in the morphology and properties of the sediment at the conditioning stage, as well as the changes in the water content and organic components of the sediment at various stages of the process (conditioning, gravity settling, HED) were analyzed. The results showed as follows: 1) The optimal dosage of Fe²⁺ and PDS for the conditioning stage was 4 mg/g (TSS) and 10 mg/g (TSS), respectively. The optimal power-on time and voltage of the HED stage were 80 min and 45 V, respectively. Under the above parameters, the water content of dredged sediment decreased from 88.55% to 55.15%. 2) At the conditioning stage, the bound water content of sediment decreased from 0.44 g/g (DS) to 0.28 g/g, the total amounts of proteins and polysaccharides in extracellular polymeric substances (EPS) increased, while the fluorescence intensity of protein-like substances and soluble microbial byproduct-like materials (SMBP) in Slime layer decreased. The total fluorescence intensity in the tightly bound EPS (TB-EPS) increased to 12.40×10⁷ AU·nm². At the HED stage, the effect of electric field led to further release of the organic matters in the sediment around the cathode region, and the fluorescence intensity of SMBP in each layer of EPS around the cathode region increased significantly. 3) SO₄ ⁻· produced at the conditioning stage could oxidize and crack the microbial cells in the sediment and release the intracellular contents into EPS, and the simultaneous changes in water distribution and EPS components of the sediment occurred. Fe(Ⅲ) produced in situ altered the floc structure of the sediment through coagulation, thus contributing to the improvement of the dewatering performance of the sediment. The research showed that Fe²⁺-PDS conditioning-HED process could effectively reduce the water content of the dredged sediment, so as to provide technical support for the treatment of dredged sediment.
- dredged sediment /
- Fe²⁺-PDS conditioning /
- horizontal electro-dewatering /
- dewatering performance /
- extracellular polymeric substances (EPS)

HTML全文

图 1 重力沉降与HED试验装置

Figure 1. Experimental device of gravity settling and horizontal electro-dewatering

下载: 全尺寸图片幻灯片

图 2 CST测定装置示意

Figure 2. Schematic diagram of CST testing device

下载: 全尺寸图片幻灯片

图 3 Fe²⁺和PDS投加量对底泥SCST及SRF的影响

Figure 3. Effect of Fe²⁺ and PDS dosage on SCST and SRF of the sediment

下载: 全尺寸图片幻灯片

图 4 电场条件对底泥含水率和脱水能耗的影响

Figure 4. Influence of the electric field conditions on the sediment water content and dewatering energy consumption

下载: 全尺寸图片幻灯片

图 5 调理前后底泥SEM图

Figure 5. SEM images of the sediment before and after conditioning

下载: 全尺寸图片幻灯片

图 6 Fe²⁺-PDS调理-HED工艺各阶段底泥的DSC热谱图

Figure 6. DSC thermograms of sediment at different stages of Fe²⁺-PDS conditioning-HED process

下载: 全尺寸图片幻灯片

图 7 Fe²⁺-PDS调理-HED工艺各阶段底SCOD的变化

工艺阶段：1—原始底泥；2—调理阶段；3—重力沉降阶段；4—HED阶段（阴极区）；5—HED阶段（阳极区）。

Figure 7. Variations of SCOD at different stages of Fe²⁺-PDS conditioning - HED process

下载: 全尺寸图片幻灯片

图 8 Fe²⁺-PDS调理-HED工艺各阶段TOC浓度的变化

注：同图7。

Figure 8. Variations of TOC at different stages of Fe²⁺-PDS conditioning - HED process

下载: 全尺寸图片幻灯片

图 9 Fe²⁺-PDS调理-HED工艺各阶段EPS各层中蛋白质、多糖、腐殖酸浓度变化

注：同图7。

Figure 9. Variations of proteins, polysaccharides and humic acids contents of EPS layers (Slime, LB-EPS, TB-EPS) at different stages of Fe²⁺-PDS conditioning-HED process

下载: 全尺寸图片幻灯片

图 10 不同阶段底泥EPS各层的三维荧光光谱图

Figure 10. EEM fluorescence spectra of each layer in sediment EPS at different stages of Fe²⁺-PDS conditioning - HED process

下载: 全尺寸图片幻灯片

图 11 Fe²⁺-PDS调理-HED工艺各阶段底泥EPS各层的荧光强度及FRI分布

注：横轴中S为Slime；L为LB-EPS；T为TB-EPS。数字代表工艺阶段：1—原始底泥；2—调理阶段；3—重力沉降阶段；4—HED阶段（阴极区）；5—HED阶段（阳极区）。

Figure 11. Fluorescence intensities and FRI distributions of each layer in sediment EPS at different stages of Fe²⁺-PDS conditioning-HED process

下载: 全尺寸图片幻灯片

表 1 试验用底泥的理化性质

Table 1. Physicochemical properties of experimental sediment

底泥批次	含水率/%	TSS/(g/L)	VSS/(g/L)	pH	毛细吸水时间/s	电导率/（mS/cm）
第一批	87.73±0.006	131.00±0.13	12.50±0.08	6.82±0.01	61.60±1.06	0.52±0.01
第二批	88.55±0.004	116.40±0.24	10.10±0.23	6.97±0.01	125.00±2.24	0.54±0.01
第三批	90.70±0.013	95.00±0.04	8.40±0.17	6.68±0.01	137.50±2.05	0.55±0.01

下载: 导出CSV

表 2 Fe²⁺和PDS投加量的试验设计

Table 2. Experimental design of Fe²⁺ and PDS dosage

试验编号	Fe²⁺投加量/（mg/g）	PDS投加量/（mg/g）
1	0	0
2	0	20
3	0	50
4	8	0
5	8	20
6	8	50
7	20	0
8	20	20
9	20	50

下载: 导出CSV

表 3 通电时间和电压的试验设计

Table 3. Experimental design of power-on time and voltage

试验组	电压/V	通电时间/min
通电时间的变化	40	10
		20
		30
		60
		120
电压的变化	10	60
	20
	30
	40
	50

下载: 导出CSV

表 4 响应曲面法试验因素水平及编码

Table 4. Code and level of factors chosen for the trials through the response surface method (RSM)

水平	Fe²⁺投加量(X₁)/（mg/g）	PDS投加量(X₂)/（mg/g）	电压(X₃)/V	通电时间(X₄)/min
−1.41	2.34	5.86	8.79	17.57
−1.00	4.00	10.00	10.00	30.00
0.00	8.00	20.00	30.00	60.00
1.00	12.00	30.00	45.00	90.00
1.41	13.66	34.14	51.21	102.43

下载: 导出CSV

表 5 FRI分析法中5个荧光分区

Table 5. Five Ex/Em regions for FRI analysis

区域	（Ex/Em）/（nm/nm）	荧光物质
Ⅰ	200~250/300~330	酪氨酸
Ⅱ	200~250/330~380	色氨酸
Ⅲ	200~250/380~500	富里酸类物质
Ⅳ	250~400/300~380	可溶性微生物副产物
Ⅴ	250~400/380~500	腐殖酸类物质

下载: 导出CSV

表 6 中心复合设计及响应值

Table 6. Central composite design and response values

序号	X₁ / （mg/g）	X₂ / （mg/g）	X₃ /V	X₄ / min	Y₁/%		Y₂/（kW·h/kg）
序号	X₁ / （mg/g）	X₂ / （mg/g）	X₃ /V	X₄ / min	实际值	预期值	实际值	预期值
1	8	20	30	102	58.53	58.97	0.30	0.35
2	4	30	15	90	61.43	61.64	0.12	0.12
3	4	30	15	30	64.71	62.51	0.10	0.07
4	8	34.14	30	60	60.30	60.28	0.40	0.39
5	4	30	45	30	56.54	57.37	0.32	0.33
6	8	20	30	60	58.73	58.91	0.21	0.28
7	8	20	30	60	61.58	58.91	0.28	0.28
8	8	20	51.2	60	57.51	56.89	0.56	0.55
9	4	10	45	90	56.23	54.99	0.31	0.28
10	12	30	15	90	63.43	63.49	0.14	0.16
11	8	20	30	60	59.01	58.91	0.23	0.28
12	8	20	8.8	60	63.47	64.18	0.03	0.01
13	12	10	15	30	65.16	63.95	0.05	0.07
14	12	30	15	30	63.47	64.94	0.06	0.06
15	4	10	15	90	61.76	61.32	0.05	0.02
16	8	20	30	60	57.91	58.91	0.26	0.28
17	12	10	45	30	60.28	60.30	0.40	0.35
18	12	30	45	90	59.44	57.97	1.04	0.91
19	8	5.86	30	60	59.49	59.60	0.23	0.16
20	4	30	45	90	54.01	54.96	0.59	0.61
21	13.66	20	30	60	58.34	58.07	0.28	0.36
22	8	20	30	60	57.85	58.91	0.23	0.28
23	4	10	15	30	62.03	63.73	0.05	0.14
24	12	10	45	90	53.85	55.79	0.46	0.52
25	12	30	45	30	60.77	60.95	0.51	0.58
26	8	20	30	60	58.51	58.91	0.31	0.28
27	12	10	15	90	61.56	60.96	0.06	0.01
28	8	20	30	18	63.09	62.74	0.32	0.20
29	2.34	20	30	60	55.43	55.79	0.19	0.19
30	4	10	45	30	59.26	58.94	0.15	0.16

下载: 导出CSV

表 7 回归方程的方差分析

Table 7. Variance analysis of regression equation

模型	相关系数（R²）	校正后相关系数（R_adj²）	均值	F	P	失拟项	显著性
Y₁	0.874 3	0.757 0	15.900 0	7.45	0.000 2	0.448 2	显著
Y₂	0.937 9	0.905 3	0.122 7	28.71	<0.000 1	0.085 2	显著

下载: 导出CSV

表 8 工艺各阶段底泥水分含量及分布

Table 8. Water content and distribution in sediment at different stages of Fe²⁺-PDS conditioning-HED process g/g　

工艺阶段	总水分	自由水	结合水
原始底泥	9.76±0.13	9.32±0.11	0.44±0.03
Fe²⁺-PDS调理阶段	9.76±0.08	9.48±0.04	0.28±0.01
重力沉降阶段	1.94±0.03	1.66±0.02	0.29±0.01
HED阶段（阴极区）	1.54±0.03	1.23±0.04	0.32±0.01
HED阶段（阳极区）	1.26±0.02	0.97±0.01	0.30±0.01

下载: 导出CSV

参考文献(33)

[1]	钱旭. 活性污泥磁化调理-电脱水性能与过程机制研究[D]. 北京: 北京林业大学, 2016.
[2]	陈雄峰, 荆一凤, 吕鑑, 等.电渗法对太湖环保疏浚底泥脱水干化研究[J]. 环境科学研究,2006,19(5):54-58. doi: 10.3321/j.issn:1001-6929.2006.05.010 CHEN X F, JING Y F, LÜ J, et al. The research of environmental dredged sludge dewatering in Taihu Lake by electro-osmotic[J]. Research of Environmental Sciences,2006,19(5):54-58. doi: 10.3321/j.issn:1001-6929.2006.05.010
[3]	季雪元, 王毅力, 冯晶.水平电场作用下活性污泥的脱水研究[J]. 环境科学,2012,33(12):4393-4399. JI X Y, WANG Y L, FENG J. Study on dewatering of activated sludge under applied electric field[J]. Environmental Science,2012,33(12):4393-4399.
[4]	MAHMOUD A, OLIVIER J, VAXELAIRE J, et al. Electro-dewatering of wastewater sludge: influence of the operating conditions and their interactions effects[J]. Water Research,2011,45(9):2795-2810. doi: 10.1016/j.watres.2011.02.029
[5]	李英华, 黄天赐, 钱杰, 等.基于过硫酸盐的高级氧化工艺修复有机污染土壤的研究进展[J]. 环境科学研究,2023,36(1):168-179. LI Y H, HUANG T C, QIAN J, et al. Persulfate based-advanced oxidation process for organic-contaminated soil remediation: a review[J]. Research of Environmental Sciences,2023,36(1):168-179.
[6]	ZHOU X, WANG Q L, JIANG G M, et al. A novel conditioning process for enhancing dewaterability of waste activated sludge by combination of zero-valent iron and persulfate[J]. Bioresource Technology,2015,185:416-420. doi: 10.1016/j.biortech.2015.02.088
[7]	LI H X, WANG Y L, ZHENG H L. Variations of moisture and organics in activated sludge during Fe⁰/S₂O₈²⁻ conditioning-horizontal electro-dewatering process[J]. Water Research,2018,129:83-93. doi: 10.1016/j.watres.2017.11.006
[8]	SHA L, WU Z X, LING Z C, et al. Investigation on the improvement of activated sludge dewaterability using different iron forms (ZVI vs. Fe(Ⅱ))/peroxydisulfate combined vertical electro-dewatering processes[J]. Chemosphere,2022,292:133416. doi: 10.1016/j.chemosphere.2021.133416
[9]	李代魁, 何萍, 刘存歧, 等.应用多种生物类群评价白洋淀水环境质量变化[J]. 应用生态学报,2021,32(12):4488-4498. LI D K, HE P, LIU C Q, et al. Evaluation of eutrophication level changes in Baiyangdian Lake based on multiple biological groups[J]. Chinese Journal of Applied Ecology,2021,32(12):4488-4498.
[10]	尹德超, 王雨山, 祁晓凡, 等. 白洋淀表层沉积物氮磷分布、储量及污染评价[J/OL]. 地质通报, 2022. (2022-03-03)[2023-01-12]. https://kns.cnki.net/kcms/detail/11.4648.P.20220301.1851.002.html. YIN D C, WANG Y S, QI X F, et al. Distribution, reserves and pollution evaluation of nitrogen and phosphorus in surface sediments of Baiyangdian Lake[J/OL]. Geological Bulletin of China, 2022. (2022-03-03)[2023-01-12]. https://kns.cnki.net/kcms/detail/11.4648.P.20220301.1851.002.html.
[11]	魏伟伟, 李春华, 叶春, 等.基于底泥重金属污染及生态风险评价的星云湖疏浚深度判定[J]. 环境工程技术学报,2020,10(3):385-391. WEI W W, LI C H, YE C, et al. Determination of dredging depth of Xingyun Lake based on heavy metal pollution and ecological risk assessment of sediment[J]. Journal of Environmental Engineering Technology,2020,10(3):385-391.
[12]	万雪娇. 白洋淀疏浚底泥处理及资源化利用技术研究[D]. 天津: 天津大学, 2019.
[13]	GAO Y F, ZHOU Y. Effect of vacuum degree and aeration rate on sludge dewatering behavior with the aeration-vacuum method[J]. Journal of Zhejiang University-Science A (Applied Physics & Engineering),2010,11(9):638-655. doi: 10.1631/jzus.A0900651
[14]	FAN X Y, WANG Y L, ZHANG D X, et al. Effects of acid, acid-ZVI/PMS, Fe(Ⅱ)/PMS and ZVI/PMS conditioning on the wastewater activated sludge (WAS) dewaterability and extracellular polymeric substances (EPS)[J]. Journal of Environmental Sciences,2020,91:73-84. doi: 10.1016/j.jes.2020.01.009
[15]	LI Y F, YANG F, MIAO S Z, et al. Achieved deep-dewatering of dredged sediments by Fe(Ⅱ) activating persulfate pretreatment: Filtrating performance and mechanistic insights[J]. Chemical Engineering Journal,2021,405:126847. doi: 10.1016/j.cej.2020.126847
[16]	GUO J Y, GAO Q F, CHEN Y H, et al. Insight into sludge dewatering by advanced oxidation using persulfate as oxidant and Fe²⁺ as activator: performance, mechanism and extracellular polymers and heavy metals behaviors[J]. Journal of Environmental Management,2021,288:112476. doi: 10.1016/j.jenvman.2021.112476
[17]	李婷, 王毅力, 冯晶, 等.活性污泥的理化性质与絮凝调理投药量的关系[J]. 环境科学,2012,33(3):889-895. LI T, WANG Y L, FENG J, et al. Relationship between physicochemical characteristics of activated sludge and polymer conditioning dosage[J]. Environmental Science,2012,33(3):889-895.
[18]	NIU M Q, ZHANG W J, WANG D S, et al. Correlation of physicochemical properties and sludge dewaterability under chemical conditioning using inorganic coagulants[J]. Bioresource Technology,2013,144:337-343. doi: 10.1016/j.biortech.2013.06.126
[19]	国家环境保护总局. 水和废水监测分析方法[M]. 4版. 北京: 中国环境科学出版社, 2002.
[20]	LEE D J, LEE S F. Measurement of bound water content in sludge: the use of differential scanning calorimetry (DSC)[J]. Journal of Chemical Technology AND Biotechnology,1995,62(4):359-365. doi: 10.1002/jctb.280620408
[21]	YU G H, HE P J, SHAO L M, et al. Stratification structure of sludge flocs with implications to dewaterability[J]. Environmental Science & Technology,2008,42(21):7944-7949.
[22]	FR/OLUND B, GRIEBE T, NIELSEN P H. Enzymatic activity in the activated-sludge floc matrix[J]. Applied Microbiology and Biotechnology,1995,43(4):755-761. doi: 10.1007/BF00164784
[23]	陈钧辉. 生物化学实验[M]. 3版. 北京: 科学出版社, 2003.
[24]	CHEN W, WESTERHOFF P, LEENHEER J A, et al. Fluorescence excitation–emission matrix regional integration to quantify spectra for dissolved organic matter[J]. Environmental Science & Technology,2003,37(24):5701-5710.
[25]	CHEN Y S, CHEN H P, LI J, et al. Rapid and efficient activated sludge treatment by electro-Fenton oxidation[J]. Water Research,2019,152:181-190. doi: 10.1016/j.watres.2018.12.035
[26]	QIAN X, WANG Y L, ZHENG H L. Migration and distribution of water and organic matter for activated sludge during coupling magnetic conditioning-horizontal electro-dewatering (CM-HED)[J]. Water Research,2016,88:93-103. doi: 10.1016/j.watres.2015.10.001
[27]	HE D Q, LUO H W, HUANG B C, et al. Enhanced dewatering of excess activated sludge through decomposing its extracellular polymeric substances by a Fe@Fe₂O₃-based composite conditioner[J]. Bioresource Technology,2016,218:526-532. doi: 10.1016/j.biortech.2016.06.139
[28]	TUAN P A, JURATE V, MIKA S. Electro-dewatering of sludge under pressure and non-pressure conditions[J]. Environmental Technology,2008,29(10):1075-1084. doi: 10.1080/09593330802180294
[29]	DIGNAC M F, URBAIN V, RYBACKI D, et al. Chemical description of extracellular polymers: implication on activated sludge floc structure[J]. Water Science and Technology,1998,38(8/9):45-53.
[30]	高诗卉. Fe⁰/Fe₃C@CS激发PMS与peroxone-Fe(Ⅲ)调理对活性污泥脱水性能的影响研究[D]. 北京: 北京林业大学.
[31]	LIU J, YANG Q, WANG D B, et al. Enhanced dewaterability of waste activated sludge by Fe(Ⅱ)-activated peroxymonosulfate oxidation[J]. Bioresource Technology,2016,206:134-140. doi: 10.1016/j.biortech.2016.01.088
[32]	YOU G X, WANG P F, HOU J, et al. Insights into the short-term effects of CeO₂ nanoparticles on sludge dewatering and related mechanism[J]. Water Research,2017,118:93-103. doi: 10.1016/j.watres.2017.04.011
[33]	GAO S H, WANG Y L, ZHANG D X, et al. Insight to peroxone-Fe(Ⅲ) joint conditioning-horizontal electro-dewatering process on water reduction in activated sludge: performance and mechanisms[J]. Journal of Hazardous Materials,2021,402:123441. ⊗ doi: 10.1016/j.jhazmat.2020.123441