Dissertation > Excellent graduate degree dissertation topics show

The Fate and Transport of POPs in Dagu Drainage River

Author: DingHui
Tutor: LiZuoGang
School: Tianjin University
Course: Chemical Engineering
Keywords: POPs HCB Dagu Drainage River fate and transport model suspended sorption-desorption settling
CLC: X522
Type: PhD thesis
Year: 2005
Downloads: 573
Quote: 10
Read: Download Dissertation

Abstract


Rivers have been severely polluted with high loads of persistent organic pollutants(POPs) in our country. But the research about the fate and transport of POPs in river is less systematically studied, presently. The environmental transport of POPs in Dagu Drainage River(DDR) selected as a typical example is reasonedly investigated in this article.Characteristics of sediment from DDR in Tianjin are analyzed. The mean value of TOC in sediments is as high as 8%, which is in favor of sorption POPs. The particle sizes of both suspended sediment and bottom sediment are mensurated by Malven Mastersizer. Silt accounts for about 60% in mass, while clay is about 10%. Particles of sediments belong to fine granule. Suspended sediment and bottom sediment mensurated by XRD mainly consist of quartz and illite, both account for 75.5% and 62.2%, respectively. The conformation of suspended sediment is very similar to bottom sediment from SEM photo.The distribution of POPs in sediments from DDR is investigated. OCPs are analyzed by GC-MS qualitatively and GC-ECD quantificationally. The result shows that DDR is severely polluted with POPs. Mean concentrations of OCPs in surface sediments are 113.73ng/g for HCHs and 40.86ng/g for DDTs, respectively, in 2005. Concentrations of HCB residues in surface sediments are higher than other OCPs residues. Concentrations of HCB range from 17.50 ng/g to 1315ng/g (mean 240 ng/g). Obviously, HCB is chief POPs in sediments from DDR. Sediments suspended from bottom are mainly source bringing POPs into river water.Sediment erosion, sorption-desorption, sedimentation environmental behaviors that closely relate to the fate and transport of POPs are investigated. Effects of bulk density and shear stress on erosion rate are researched by hydrodynamic equipment. The erosion rate formula as function of bulk density and shear stress is regressed. Experimental data of HCB desorption were simulated better by fast-slow two stage first-order kinetics model and dynamic parameters of HCB desorption were also calculated. Sorption-desorption mathematic model is built that can illustrate variation of POPs concentrations in different media with time. The concentration of suspended sediment is main factor deciding the balance time. Through the experimental data regression, the power function about Kp and SPM is regressed. Mass settling velocity of suspended sediment through experiment is similar to the calculated value withmean particle size by one particle settling in fresh water. For rivers with lower concentration of suspended sediment, effect of concentration on settling velocity is inapparent.Based on theories of pollutants movement in river and integrated with sediment erosion, sedimentation, sorption-desorption processes, the fate and transport of POPs mathematic model is built. The calibration model is used to simulate the transport of POPs in the DDR. POPs flux into bohai gulf is 4.32 Kg/d after calculation. The model prediction results will be a powerful tool for the environmental management.

Related Dissertations

  1. Activation of Polycyclic Aromatic Hydrocarbons in Soils by Root Exudate and Its Components,X53
  2. West Hubei Traditional Common People Residence Decoration Mark and Design Applied Research,TU-05
  3. Influence of Phosphor Settling on Optical Consistency of High-Power LED,TM923.04
  4. The End of Zheng He’s Voyages Down the Western Seas:research the Act Suspended in Renxuan Dynasty,K248
  5. Urban sewage A ~ 2 / O Process Operation and Discussion,X703
  6. Suspended platform PMLSM Second Order Sliding Mode Control,TP273
  7. Gas vortex wafer clamping conveyor system design,TH22
  8. Study on the Optimal Design and On-site Construction of Subgrade Suspendible Anchor Retaining Wall,U417.11
  9. The Design and Stability Analysis of Subgrade Cantilever-anchor Retaining,U417.11
  10. The Numerical Simulation of the Non-equilibrium Transportation of Suspended Sediment and the Erosion Prediction of Rivers,TV142.3
  11. The Pilot Study of the Effect of White-Mud Desulfurization Sea-Water to Marine Environment in Jiaozhou Bay,X55
  12. Experimental and Numerical Studies on the Gas-solid Two-phase Flow of Indoor Inhalable Particles,X513
  13. Flocculation and Filter Experiment of Effluent from T6 Tube,X703
  14. Emission Characteristics and Catalytic Degradation Reactor of UP-POPs in Municipal Solid Waste Incineration,X799.3
  15. Integrated Measurement for Density and Viscosity of Heavy Medium Suspension Based on Differential Pressure,TD94
  16. Continuous Ethanol Fermentation Using Self-flocculating Yeast Cells Coupled with Distillage Recycling,TQ920.1
  17. The Experimental Research of Shaking Table on Earthquake Simulation of the Suspended Mass System Structure,TU317
  18. Study of Disposal the BHC in Drinking Water by UV-catalyze Oxidation,TU991.2
  19. Determining Suspended Sediment Concentration of Yellow River Delta Based on Electrical Conductivity,TV148.1
  20. Material Transport and Study of Dynamic Mechanism in the Yangtze River Estuary,TV148.1
  21. Azithromycin enteric-coated pellets , pellets Stomach,R94

CLC: > Environmental science, safety science > Environmental pollution and its prevention > Water pollution and its control > River
© 2012 www.DissertationTopic.Net  Mobile