Centrifuge Dewatering

Category:

Sediment handling

Description:

Dewater dredge sediments using centrifuges in conjunction with flocculents. Mechanical

dewatering is being evaluated for dredging projects as a result of the following factors:

Confined sediment placement sites within a reasonable distance of dredging area are

increasingly unavailable.

Beneficial uses for dredged sediment, such as a daily cover at landfill operations or as a soil

amendment, require dewatered material.

Many landfill sites require that dredged sediments be dewatered prior to acceptance for

disposal.

Reviewer:

C. Woolley

Company / Organization(s):

Access Restricted to U.S. Army Corps of Engineers

Projects Completed:

Capitol Lake

Location:

Olympia, Washington

Completion Date:

1995

Project Contact:

Greg Hartman

Lake Lawrence

Location:

Thurston County, Washington

Completion Date:

Project Contact:

Greg Hartman

Comments:

The Lake Lawrence Restoration Project involved shallow lake dredging

of fine sediments with high water and organic content. The purpose of

dredging was to eliminate the largest source of phosphorus loading into

the lake in order to alleviate an excess macrophyte problem. The project

scope included sediment characterization for physical and chemical

characteristics, evaluation of lake treatment alternatives (i.e. dredging or

capping sediment) and impacts, evaluation of disposal alternatives, and

preparation of detailed cost estimates for all alternatives. Hydraulic and

mechanical dredging with various types of dredge equipment were

evaluated for final design. Equipment selection was based on both

economic and production factors. Disposal alternatives evaluated included

retention facilities with enhanced settling techniques and sediment

dewatering and land application of sediment slurry as a beneficial use.

Information Sources:

Literature:

Month:

August

Year:

1996

LitType:

Periodical

Publisher:

World Dredging and Mining Construction

Page:

Notes:

See Nancy Case's paper from WEDA 1996. Includes references and

diagram of centrifuge system.

Chapter 5 Other Technologies Reviewed