Influence of thermal effect on vacuum electro-osmosis of Taizhou dredged sediment

The purpose of this study was to test whether electro-osmosis can be used to increase the effectiveness of dewatering of dredged sediment being drained in geo- textile tubes. The marine sediment used in the study had a high proportion of clay known to be problematic in geo-tube treatment. The laboratory set-ups were performed using sediment-filled sacks (approximately 5-7 liters / sack) sewn from geo-textile (TenCate Geotube® GT500), and plastic columns (approximately 1.6 liters / column) closed at the bottom with geo-textile, both supplied with electrodes for applying direct current. In the sack set-ups, a seven-hour electric treatment led to the same result as the 72-hour control treatment. The volume of the sediment decreased in column set-ups by 32 % due to electric treatment while only a 14 % decrease was obtained in the controls after 189 hours. The water layer on top of the sediment treated with electro-osmosis decreased by up to one-fifth, as compared to the control columns. We can conclude that electro-osmosis is an effective approach to boost the dewatering of the dredged sediment treated in geo-textile tubes. When draining sediment with a high clay content, electric treatment can prevent the formation of a water column on top of the sediment. This in turn accelerates dewatering of the dredged material.

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UHV-STM studies of silicon nano-pyramid growth on silicon surface at high temperature

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130353 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1144-1145

Author(s):

T. Sato ◽

S. Kitamura ◽

T. Sueyoshl ◽

M. Iwatukl ◽

C. Nielsen

Keyword(s):

High Temperature ◽

Relaxation Process ◽

Thermal Effect ◽

Bias Voltage ◽

Silicon Surface ◽

Growth Process ◽

Tunneling Current ◽

Fabrication Technique ◽

Nano Fabrication ◽

Electromigration Effect

Recently, the growth process and relaxation process of crystalline structures were studied by observing a SI nano-pyramid which was built on a Si surface with a UHV-STM. A UHV-STM (JEOL JSTM-4000×V) was used for studying a heated specimen, and the specimen was kept at high temperature during observation. In this study, the nano-fabrication technique utilizing the electromigration effect between the STM tip and the specimen was applied. We observed Si atoms migrated towords the tip on a high temperature Si surface.Clean surfaces of Si(lll)7×7 and Si(001)2×l were prepared In the UHV-STM at a temperature of approximately 600 °C. A Si nano-pyramid was built on the Si surface at a tunneling current of l0nA and a specimen bias voltage of approximately 0V in both polarities. During the formation of the pyramid, Images could not be observed because the tip was stopped on the sample. After the formation was completed, the pyramid Image was observed with the same tip. After Imaging was started again, the relaxation process of the pyramid started due to thermal effect.

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Molecular simulation of osmosis, reverse osmosis, and electro-osmosis in aqueous and methanolic electrolyte solutions

Molecular Physics ◽

10.1080/002689798166729 ◽

1998 ◽

Vol 95 (3) ◽

pp. 401-408 ◽

Cited By ~ 2

Author(s):

S. MURAD K. ODER J. LIN

Keyword(s):

Reverse Osmosis ◽

Molecular Simulation ◽

Electrolyte Solutions ◽

Electro Osmosis

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Effect of Pavement Material’s Thermal Properties on Thermal Effect of Urban Underlying Surface

CICTP 2020 ◽

10.1061/9780784483053.173 ◽

2020 ◽

Author(s):

Huan Liu ◽

Jianzhong Pei ◽

Jiupeng Zhang ◽

Xueqian Li

Keyword(s):

Thermal Properties ◽

Thermal Effect ◽

Underlying Surface

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Applicability of electrodialysis to the separation of sodium acetate from synthetic alkaline hardwood extract

TAPPI Journal ◽

10.32964/tj14.11.695 ◽

2015 ◽

Vol 14 (11) ◽

pp. 695-708 ◽

Cited By ~ 3

Author(s):

RAVIKANT PATIL ◽

CHI TRUONG ◽

JOSEPH GENCO ◽

HEMANT PENDSE ◽

ADRIAAN VAN HEININGEN

Keyword(s):

Current Density ◽

Sodium Sulfate ◽

Sodium Acetate ◽

Separation Efficiency ◽

Feed Concentration ◽

Initial Concentration ◽

White Liquor ◽

Complete Extraction ◽

Electro Osmosis ◽

Preliminary Separation

Our objective was to develop a process for recovering acetyl groups from industrial northeast hardwood chips. Extraction experiments showed that the white liquor charge of 6% effective alkali at 50°C and liquor-to-wood ratio of 4:1 leads to the complete extraction of acetyl groups from industrial hardwood chips. Electrodialysis was assessed as a technique for separating and concentrating sodium acetate from synthetic hardwood extract. Preliminary separation experiments using dilute sodium acetate showed that the sodium acetate can be concentrated up to approximately 24% by weight from an initial concentration of about 2% by weight. The effects of current density, feed concentration, electro-osmosis, and osmosis on the separation of sodium acetate were evaluated. Finally, selectivity experiments were performed to study the effect of various components of the white liquor on the separation of sodium acetate. Fully oxidized synthetic white liquor was used in selectivity experiments to avoid deleterious effects of Na2S. Selectivity experiments using synthetic oxidized white liquor showed a significant decrease in the separation efficiency due to the presence of sodium hydroxide, sodium carbonate, and sodium sulfate in the synthetic extract.

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