مقايسه آثار پوست گردو، رس و كربن فعال پودري بر روي ته نشين پذيري لجن فعال

Comparison of Influence of Walnut Shell, Clay and Powdered Activated Carbon on Settleability of Activated Sludge

The activated sludge process is the most used biological wastewater treatment method in the industries. The separation of solids in the activated sludge process is a very important function in order to provide well-clarified effluent and concentrated solids that are returned to the biological treatment system or are wasted to the solids processing facilities. There are two main types of settling problems: (i) bulking sludge due to the proliferation of filamentous bacteria and (ii) poor flocculation properties, e.g. formation of small and light flocks. In most cases, large, dense and strong flocks are desirable for good settling and compaction of activated sludge. Two commonly used measures developed to quantify the settling characteristics of activated sludge are the sludge volume index (SVI) and the zone settling velocity (ZSV). The sludge volume index (SVI) is the volume in milliliters occupied by 1 g of a suspension after 30 min settling. SVI values below the 100 mL/g are typically associated with good settling sludge. Also 100