Sludge Handling SLU

Identify two types of sludges and three classes of sludge generated by wastewater treatment processes. 

Primary Sludge Primary sludge is generated during primary wastewater treatment, which removes those solids that settle out readily. Primary sludge contains 2-8% solids usually thickening or other dewatering operations can easily reduce its water content. 

Settled sludge is a by-product of wastewater treatment. It usually contains 95-99.5% water as well as solids and dissolved substances that were present in the wastewater or were added during wastewater treatment processing. Usually these wastewater solids are further dewatered to improve their characteristics prior to ultimate use/disposal. 

The characteristics of a sludge can significantly affect its suitability for the various use/disposal options. Thus, when evaluating sludge use/disposal alternatives, one should first determine the amount and characteristics of its sludge and the degree of variation in these characteristics. 

List and describe the three methods involved for wastewater sludge management. 

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