AWWA ACE69076

A large majority of clearwells must be modified while maintaining the original baffles,since they were built underground with materials like concrete. Therefore, it isunreasonable to apply the previous research in clearwell modification which assumedthat distance between baffles is constant. In this study, the internal short-circuitingestimation method (ISEM), which has the advantage of being applicable under anyconditions, is applied to evaluate modification of an A clearwell and to modify B and Cclearwells which have unusual characteristics. After analyzing the hydraulic efficiencyof the original state, modifications, where baffles, intra-basins and diffuser walls areadditionally installed, are considered and evaluated using the ISEM. The effect of intra-basinand diffuser walls on T₁₀/T is estimated and the application feasibility of ISEM isevaluated. The improvement provided by intra-basins is almost the same as that ofbaffles. Also, short-circuiting in the effluent zone can be reduced with the same level ofchannel zone if an intra-basin is added in the effluent zone. However, the effect range isrestricted to the next channel zone. A diffuser wall can obtain a lower ISI than ispossible in cases where baffles and intra-basins are installed. Therefore, additionalimprovement of the T₁₀/T value can be expected after the T₁₀/T value convergesmaximum using only baffles Includes 13 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2008

Number of Pages:

45

File Size:

1 file , 1.5 MB