During the process of water & wastewater treatment, sludge generation is an important and at times crucial issue to be addressed as inadequate sludge handling system can pose serious environmental implications. The sludge can be organic or inorganic as a consequence of treatment process and each of this sludge variety needs specific handling before it is fit for disposal as per client's requirement which sometimes is dictated by the environmental issues in their respective areas. Organic sludge may need further biological treatment before they can be disposed off after dewatering and drying.

This is necessitated because the organic sludges carry lot of bacteria and dead organic matter. Uncontrolled decomposition of the organic sludges may lead to unhygienic conditions leading to spread of diseases and odors and as such adequate treatment prior to disposal is desired for such organic sludge. In the case of inorganic sludge emanating from water & wastewater treatment processes, these can be taken for disposal only after adequate treatment for any hazardous chemicals which may pose environmental problems after disposal like groundwater contamination due to leaching into the groundwater sources especially during wet weather conditions.

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