Sequestration of Heavy Metals From Coal Wash Water Using Biochar From Pyrolysis of Morula Shells

Tumeletso Lekgoba; Lame Elsie Othugile; Freeman Ntuli

doi:10.21601/ejosdr/11377

Use of hydrocyclone and flotation column for reducing the volume of contaminated dredged material

Water Science & Technology ◽

10.2166/wst.2006.219 ◽

2006 ◽

Vol 53 (7) ◽

pp. 151-157 ◽

Cited By ~ 5

Author(s):

K.H. Park ◽

J.H. Lee ◽

B.H. Bae ◽

Y.H. Kim ◽

Y.K. Choung

Keyword(s):

Heavy Metals ◽

Integrated Treatment ◽

Reduction Ratio ◽

Volume Reduction ◽

Wash Water ◽

Column Flotation ◽

Preliminary Treatment ◽

Primary Concern ◽

Flotation Column ◽

Transmission Oil

As sediment contamination problems have recently been raised in Korea, the need for technologies to clean contaminants in sediments has increased. Although the recalcitrant organic matters and heavy metals in the contaminated sediments are of primary concern, large amounts of sediment makes the removal of the contaminants in them more difficult. In this study, the performance of hydrocyclone and flotation column was tested to reduce the volume of contaminated dredged materials (CDMs) prior to treating recalcitrant matters, such as various organic chemicals and heavy metals, in an integrated treatment system. When hydrocyclone was operated with 10% (w/v) solids concentration of the feed slurry, the total solids of upflow products were 4 to 7% (w/v) when the inlet pressure was changed from 1.0 to 2.0 kg/cm2. The volume reduction ratio of CDMs by hydrocyclone was approximately 90% (v/v). When the upflow products in hydrocyclone was then spiked with automobile transmission oil and fed to the flotation column to see the performance of the column flotation on the volume reduction and the TPH removal, 44% of the TPHs in feed were removed at the tails and the volume reduction ratio of CDMs by column flotation was 18% at 200 L/min of wash water. The flotation column could be proposed as a potential preliminary treatment process of CDMs prior to subsequent biological treatments.

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Sampling and analysis of the air-water interface with SEM and EDS of microlayers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100157000 ◽

1989 ◽

Vol 47 ◽

pp. 1004-1005

Author(s):

Randall W. Smith ◽

John Dash

Keyword(s):

Heavy Metals ◽

Surface Microlayer ◽

Surface Films ◽

Water Interface ◽

Physical Processes ◽

Infrared Spectroscopic Analysis ◽

Eds Analysis ◽

Air Water Interface ◽

Significant Area ◽

Bulk Chemical

The structure of the air-water interface forms a boundary layer that involves biological ,chemical geological and physical processes in its formation. Freshwater and sea surface microlayers form at the air-water interface and include a diverse assemblage of organic matter, detritus, microorganisms, plankton and heavy metals. The sampling of microlayers and the examination of components is presently a significant area of study because of the input of anthropogenic materials and their accumulation at the air-water interface. The neustonic organisms present in this environment may be sensitive to the toxic components of these inputs. Hardy reports that over 20 different methods have been developed for sampling of microlayers, primarily for bulk chemical analysis. We report here the examination of microlayer films for the documentation of structure and composition.Baier and Gucinski reported the use of Langmuir-Blogett films obtained on germanium prisms for infrared spectroscopic analysis (IR-ATR) of components. The sampling of microlayers has been done by collecting fi1ms on glass plates and teflon drums, We found that microlayers could be collected on 11 mm glass cover slips by pulling a Langmuir-Blogett film from a surface microlayer. Comparative collections were made on methylcel1ulose filter pads. The films could be air-dried or preserved in Lugol's Iodine Several slicks or surface films were sampled in September, 1987 in Chesapeake Bay, Maryland and in August, 1988 in Sequim Bay, Washington, For glass coverslips the films were air-dried, mounted on SEM pegs, ringed with colloidal silver, and sputter coated with Au-Pd, The Langmuir-Blogett film technique maintained the structure of the microlayer intact for examination, SEM observation and EDS analysis were then used to determine organisms and relative concentrations of heavy metals, using a Link AN 10000 EDS system with an ISI SS40 SEM unit. Typical heavy microlayer films are shown in Figure 3.

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