Order this information in Print

Order this information on CD-ROM

Download in PDF Format


Click here to make tpub.com your Home Page

Page Title: Suspended Solids Removal
Back | Up | Next

Click here for a printable version




Information Categories
.... Administration
Food and Cooking
Nuclear Fundamentals
  Educational CD-ROM's
Printed Manuals
Downloadable Books


Framework for Dredged Material Management
May 2004
Contaminants in these streams will present a wide array of concentrations
depending on their source, and individual sources are often highly variable in
concentrations and flows. Most of the contaminants for these streams (with the exception
of leachate) are associated with the suspended solids and will be removed by effective
suspended solids removal. Another characteristic of these streams is their variety of
contaminants, both organic and inorganic, as well as potentially toxic contaminants.
These characteristics may require more than one treatment process. Commonly used
wastewater treatment processes are available to achieve effluent limits for most
contaminants. However, application of treatment processes for dredged material effluent
has been generally limited to removal of suspended solids and contaminants associated
with these particulates.
Liquid treatment technologies can be classified as metals removal processes,
organic treatment processes, and suspended solids removal processes. Many of these
processes concentrate contaminants into another phase, which may require special
treatment or disposal. This discussion focuses on suspended solids, toxic organics, and
heavy metals. Conventional contaminants, such as nutrients, ammonia, oxygen-
demanding materials, and oil and grease, may also be a concern for dredged material
effluents. Most of the processes for dissolved organics removal are suitable for these
contaminants. Suspended Solids Removal
Suspended solids removal is the most important liquid streams technology
because it offers the greatest benefits in improving effluent quality not only by reducing
turbidity but also by removing particulate-associated contaminants. Suspended solids
removal processes differ from dewatering processes because for this application the
solids concentration is much lower than for a dredged material slurry. Settling
mechanisms for these streams are characterized by flocculent settling rather than zone or
compression settling. For CDF liquid streams, the solids remaining will be clay or
colloidal size material that may require flocculants to promote further settling in clarifiers
or sedimentation ponds. Chemical clarification using organic polyelectrolytes is a proven
technology for CDF effluents (Schroeder 1983). Filtration, permeable dikes, sand-filled
weirs, and wetlands have also been used on occasion for CDF demonstrations or pilot
evaluations. More detailed guidance on suspended solids removal processes as applied to
CDFs is available (USACE 1987; Cullinane et al. 1986). Metals Removal
Metals removal processes that may be considered for application at CDFs are
similar to those commonly used for industrial applications. Flocculation is effective for
removal of metals associated with particulate matter. Polymers and inorganic flocculants
have been demonstrated to be effective for removal of suspended solids from dredging
effluents, but removal of dissolved heavy metals has not been evaluated in field
applications. Ion exchange and precipitation are probably two of the more efficient
metals removal processes, but they must generally be designed for specific metals and

Privacy Statement - Press Release - Copyright Information. - Contact Us - Support Integrated Publishing

Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business