Investigation of Tubifex Worms Potential in Mass and Volume Reduction of Sludge Wastewater Treatment Plants in Laboratory Scale

Document Type : Research Paper



Large amount of excess waste from activated sludge is generated in wastewater treatment plants which its treatment, transportation and disposal costs are estimated to be over 50 percent of total  plant cost operation. In this research it was tried to decrease the amount of sludge volume and its mass by using relative low cost and low energy consumed  process in laboratory scale. By developing suitable environmental conditions and population increase and growth of aquatic Tubifex worms in sludge (conventional kinds of worms in wastewater treatment plants) and with measurement of TSS, VSS and worms growth rate, sludge mass and volume reduction were determined. According to the results, in specific growth rate of 0.05 d-1, VSS reduction of 26 mg/l.d and with initial sludge amount of 2850 mg/l and 2000 mg/l, TSS and sludge volume reduction of 40 and 20 percent were observed, respectively. 50 percent of soluble COD with initial amount of 500 mg/l was also removed in the laboratory conditions.


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