Sludge digested

Table 3. Comparison of Filters on Aerobically Digested Sludges ...

Aerobically digested sludge usually has good dewatering characteristics. When applied to sand drying beds, it drains well and redries quickly if rained upon. 

In plants with primary and secondary digester, raw sludge is pumped to the primary digester displacing partially digested sludge. 

Completely digested sludge usually filters more readily than partially digested sludge. 

Digested sludge has been said to be somewhat comparable to farm manure in its content of fertilizer constituents, their relative availability and the physical nature of the material. 

Water treatment Clarification of potable water, industrial effluents, municipal waste water thickening and dewatering of sludge filtration of primary sludge, digested sludge food processing... 

Battersby NS, V Wilson (1989) Survey of the anaerobic biodegradation potential of organic chemicals in digesting sludge. Appl Environ Microbiol 55 433-439. 

The sulfides of trace elements in soils and sediments are also of importance in controlling the availability and mobility of trace elements, especially for land disposal of sulfide-rich sediments or anaerobic digested sludge. Due to the oxic nature in arid soils, most of the sulfur is present as sulfate thus, this problem may not be pressing. In most current SSD schedules, the majority of the sulfide forms are included in the organic bound or residual fractions. 

Aerobic digested sludge 0.02-0.4 0.11 1 Activated sludge + nitrification/ denitrification Australia [9]... 

Carballa M, Omil F, Ahad JME (2009) Influence of different pretreatments on anaerobically digested sludge characteristics suitability for final disposal. Water Air Soil Pollut 199 311-321... 

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