O efeito do hidrograma e da concentração afluentes na remoção de material particulado em canal gramado
Alternative titleThe effect of hydrograph and of inlet concentration in particle removal on grassy channel
MetadataShow full item record
The present work investigated the effect of hydrograph and inlet concentration on the removal of particle matter on a constructed real scale grassy channel. For this, three input hydrographs and initial concentration (Co) of particulate matter were investigated, as following: 65; 130; 195; 263, 327 and 400 mg/L, which were discharged in a grassy channel with 100 m length and a 2% slope. The peak of the hydrographs investigated was around 11±2 L/s; and the time base (tB), determined in the unloading point on the channel, ranged between 15, 25 and 35 minutes. The transit time in the channel (tT) was about 10.5±2.5 minutes, corresponding to a speed of 0.14±0.02 m/s. For 15 minutes tB, the average of maximum efficiencies was around 64±3% for the position 31±26 m. For 25 minutes tB, it was around 73±3% for 59±24 m. Finally, for 35 minutes tB the average of maximum efficiencies was about 65±3% for 73±15 m. It was verified that 70% of the values of the decay constant (kd) are between 0.005 and 0.015 s-1; and, when the tB of 15 minutes is not considered, 90% of the data is in the range of 0.005≤ kd ≤0.015 s-1. Also, a direct and proportional behavior of the final concentration (C*) and the initial concentration (Co) was identified.