Sludge adsorption

TREATABILITY/REMOVABILITY Process, Removable Range (%), Avg. Achievable Cone. (pg/L)) Gravity oil separation, not available, 3 Activated sludge (based on synthetic wastewater), 0, not available Powdered activated sludge adsorption (based on synthetic waste-water), 95, 1.2... 

Steber, J. Wierich, P. "Properties of aminotris(methylenephosphonate) affecting its environmental fate degradability, sludge adsorption, mobility in soils, and bioconcentration", Chemosphere 1987,16, 1323-1337. 

Biodegradable organic matter (biochemical oxygen demand (BOD)) Microbial fuel cell (MFC) Activated sludge Adsorption n.r. n.r. 147... 

Most carbon adsorption units use granular activated carbon (GAC). The powdered form of activated carbon (PAC) typically is less than 100 microns in diameter and may be used to reduce dioxins in incinerator emissions (2) and in the treatment of drinking water and wastewater treatment (see the section on "Activated Sludge"). 

Filter aids may be applied in one of two ways. The first method involves the use of a precoat filter aid, which can be applied as a thin layer over the filter before the suspension is pumped to the apparatus. A precoat prevents fine suspension particles from becoming so entangled in the filter medium that its resistance becomes exces-sive. In addition it facilitates the removal of filter cake at the end of the filtration cycle. The second application method involves incorporation of a certain amount of the material with the suspension before introducing it to the filter. The addition of filter aids increases the porosity of the sludge, decreases its compressibility, and reduces the resistance of the cake. In some cases the filter aid displays an adsorption action, which results in particle separation of sizes down to 0.1 /i. The adsorption ability of certain filter aids, such as bleached earth and activated charcoals, is manifest by a decoloring of the suspension s liquid phase. This practice is widely used for treating fats and oils. The properties of these additives are determined by the characteristics... 

The most important removal pathways of PhACs during wastewater treatment are biotransformation/biodegradation and abiotic removal by adsorption to the sludge. The efficiency of their removal at WWTP depends on their physico-chemical properties, especially hydrophobicity and biodegradability, and process operating parameters (i.e., HRT, SRT, and temperature). For certain NSAIDs (e.g., ibuprofen, acetaminophen), high removals (>90%) are consistently reported in literature... 

The resnlting sludge can be nsed to mannfactnre bnilding materials, road cover materials, and the like. Adsorptive pnrihcation is able to liberate the water from contaminants that cause its bad smell and taste. It is highly effective for the removal of xenobiota and of traces of petrolenm prodncts. In some cases it can even decolorize the water. 

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