生物质活性炭原位修复有机物污染底泥技术研究与应用

Research and Application of In-Situ Activated Biochar Amendment for Organic Contaminated Sediment Remediation

污染底泥是水体中重要的内源污染,生物质活性炭作为原位修复技术的覆盖材料,正在逐步应用于污染底泥的原位修复.应用椰壳颗粒活性炭与果壳颗粒活性炭对有机物污染底泥进行原位修复,测定2种生物质活性炭的比表面积、孔径分布、表面官能团等理化性质,并应用2种生物质活性炭进行了原位治理污染底泥的实验室静态模拟试验和实地现场试验,在实地现场试验中增加煤基活性炭与2种生物质活性炭进行对比.结果表明:(1)2种生物质活性炭的表面性质与化学组成相似,但椰壳颗粒活性炭比表面积较大,微孔孔隙结构略微发达,极性基团较少.(2)实验室静态模拟试验中,2种生物质活性炭对底泥中的PAHs (多环芳烃)、PAEs (酞酸酯)和苯系物(benzenes) 3类有机污染物均有很好的稳定化修复效果,投加生物质活性炭10个月后,底泥孔隙水中3类污染物的质量浓度降低93. 2%以上;对不同种类有机污染物,孔隙水降低率略有差距,与2种生物质活性炭理化性质的差异有关.(3)实地现场试验中,2种生物质活性炭和煤基活性炭对3类有机污染物的稳定化修复效果均呈现PAEs>PAHs>苯系物,煤基活性炭的修复效果略高于2种生物质活性炭.研究显示,在10个月的修复时间下,生物质活性炭对有机物污染底泥有明显的修复效果,可使底泥孔隙水中PAHs、PAEs和苯系物类有机污染物质量浓度降低90%以上,并且与煤基活性炭相比,生物质活性炭对环境造成的污染印迹更小.

Contaminated sediment is an important endogenous source of pollution in water bodies.Research on the control of sediment contamination has received much attention.As an in-situ remediation technology,biomass activated carbon is gradually being applied to the treatment of polluted sediment.In order to study the mechanism of coconut shell granular activated carbon and fruit shell granular activated carbon treatment of organic contaminants in the sediment,the physicochemical properties such as specific surface area,pore size,and surface functional groups of the two activated carbons were determined.Laboratory static simulation and field experiments of in-situ remediation of organic contaminated sediment were conducted and compared with traditional coal-based activated carbon.The experimental data indicated that:(1)The surface properties and chemical composition of the two biomass activated carbons were similar.Compared with fruit shell granular activated carbon,coconut shell granular activated carbon had a larger specific surface area,slightly more porous structure,and fewer polar groups.(2)Laboratory static simulation experiments show that both biomass activated carbons had a good stabilizing effect on polycyclic aromatic hydrocarbons (PAHs),phthalate esters (PAEs) and benzenes in the sediment.After adding the biomass activated carbon for 10 months,the concentrations of 3 pollutants in sediment pore water decreased by more than 93.2%.There was a slight difference in the decrease rate of the pore water concentrations among different organic contaminants.The biomass activated carbons were slightly less effective that the coal-based activated carbon.The application of biomass activated carbon to contaminated sediment remediation needs further study.