Sludge drying lagoons

Sludge Evaporation Lagoons (Sludge Drying Lagoons)... 

Operating procedures common to all types of sludge drying lagoons involve ... 

The advantages of using sludge evaporation lagoons (or sludge drying lagoons) are... 

Table 2 indicates labor requirements for sludge drying lagoons. The requirements include periodic removal of solids and minor maintenance requirements, such as dike repair and weed control. No information is available on maintenance material costs. 

Fig. 6. Cable and scraper system for sludge drying lagoons.

The type of sludge to be placed in the lagoon can significantly affect the amount and type of odor and vector problems that may be produced. It is recommended that only those sludges that have been anaerobically digested be used in drying lagoons. 

Although the sludge evaporation lagoon process is also called a sludge drying process, there is a difference between evaporation and drying. 

The feasibility of cleaning PCB contaminated solids via a solvent extraction route was studied, using the cleanup of the dried sludge from the Winston-Thomas tertiaty lagoon as a test problem. 

The limitations for evaporation lagoons include local health ordinances potential for odors and health hazard when not properly designed land area requirements dependence on meteorological and climatological conditions. Sludge lagoons may require provisions to add makeup water to maintain a miiumum depth during dry, hot seasons. Finally, public access restrictions are necessary. 

Sludge Treatment. The Lagoon chemical sludge was very waxy and did not readily give up entrained water. A pretreatment process was developed by our laboratory which allowed this sludge to be readily dewatered. The result was conversion of this difficult-to-transport material into a relatively dry, sandy textured material. The... 

TREATABILITY/REIMOVABILITY (Process, Removable Range (%), Avg. Achiev able Cone. (pg/L)) Aerated lagoons, 0, negative removal Activated sludge, 47->97, 0.4 Acti vated sludge (based on synthetic wastewater), 56, 2200 Powdered activated carbon adsorptiot (based on synthetic wastewater), 90, 79,000 can be physically removed by washout by rainfal and dry deposition... 

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