Effects of calcium oxide on the surface properties of municipal wastewater sludge and its co-slurrying ability with coal.
Effects of calcium oxide on the surface properties of municipal wastewater sludge and its co-slurrying ability with coal.
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DOI：
10.1016/j.scitotenv.2013.03.069
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发表时间：
2013-07
期刊：
影响因子：
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通讯作者：
Ruikun Wang;Jianzhong Liu;Y. Yu;Junhu Zhou;K. Cen
中科院分区：
文献类型：
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作者：
Ruikun Wang;Jianzhong Liu;Y. Yu;Junhu Zhou;K. Cen
城市化产生了大量的城市污水污泥（简称污泥），威胁着环境和人类健康。因此，以具有成本效益的方式利用污泥是一个重要的问题。污泥是一种含碳物质，与煤粉混合可制成煤泥浆。然而，由于污泥中亲水基团的丰富和其松散的絮凝体结构，原污泥的成浆性相对较差。在这项研究中，改性的污泥与氧化钙（CaO）表现出积极的影响污泥成浆性。煤泥水的特性粘度为1635.3mPas。在用2 wt.%的污泥改性后，CaO处理24 h后，CSS粘度降至1184.4mPas。随着CaO投加量从0%增加到4%，污泥中疏水基团（CC和CH）含量从61.5%增加到74.9%，Zeta电位从-55.1eV增加到-36.2eV。CaO的最佳添加量为2 wt.%。与R-CSS相比，煤改性污泥浆（M-CSS）具有较低的屈服应力、较弱的假塑性和触变行为以及较差的静态稳定性。
Urbanization has generated large volumes of municipal wastewater sludge (sludge for short) that threaten the environment and human health. As such, utilization of the sludge in a cost-effective manner is an important concern. The sludge, as a carbon-containing material, can be made into coal-sludge slurry (CSS) by mixing it with pulverized coal. However, the slurryability of the raw sludge is relatively poor due to the abundance of hydrophilic groups in the sludge and its loose floc structure. In this study, modification of the sludge with calcium oxide (CaO) showed positive effects on the sludge slurryability. The characteristic viscosity of the coal raw-sludge slurry (R-CSS) was 1635.3mPas. After modification of the sludge with 2wt.% CaO for 24h, the CSS viscosity decreased to 1184.4mPas. The hydrophobic group (CC and CH) content of the sludge increased from 61.5% to 74.9% as the CaO dosage increased from 0% to 4%, and the zeta potential increased from –55.1eV to –36.2eV. The optimum CaO dosage for improved slurryability was found to be 2wt.%. Compared with R-CSS, the coal modified-sludge slurry (M-CSS) showed lower yield stress, weaker pseudoplastic and thixotropic behaviors, and poorer static stability.