||Processing Characteristics of Subsurface Macrophytes of Madison, Wisconsin Lakes in Relation to Mechanical Harvesting Systems.
Livermor, D. F. ;
Bruh, H. D. ;
Polloc, B. W. ;
||Wisconsin Univ., Madison. Water Resources Center.
||OWRR-B-018-WIS; 01197,; B-018-WIS(1)
( Aquatic plants ;
Water quality ;
||Some EPA libraries have a fiche copy filed under the call number shown.
Equipment has been developed to harvest subsurface macrophytes to depths of one to one and one-half meters, thus freeing the lake subsurface for boating and other recreational purposes without seriously disturbing the vegetation and fish habitat at greater depth. To facilitate handling and reduce operating costs, research was conducted on numerous methods of vegetation processing. Two methods of processing were found to offer possibilities in converting aquatic vegetation to a state more readily handled and transported. Fluidizing by intensive chopping and grinding reduces the vegetation to a slurry which can then be handled and transported as a fluid. A second alternative is mechanically dewatering the vegetation by chopping and pressing. The fluid fraction is returned to the body of water while press residue is reduced to 12 to 16% of the original volume and 23 to 32% of its original weight. Approximately 90% of the original solids, 85% of the protein, 60% of the potassium, and 80% of the phosphorus present in the vegetation as harvested is removed in the press residue. The effects of returning the liquid fraction to the body of water are not known. (Author)