An SDI test was performed to evaluate the fouling tendency of potential RO source water. The time to collect 500 mL of water was measured as 24 seconds. Filtration continued for a total of 15 minutes, and then a second 500 mL was collected. The time necessary to collect the second 500 mL sample was 32 seconds. Calculate the SDI.

The SDL cannot be determined based on the given information because there was no change in the volume of the samples collected. The formula for calculating the SDI requires a non-zero change in volume.

To calculate the SDI (Silt Density Index) in this scenario, we need to use the formula:
SDL = (time2 - time1) / (volume2 - volume1)

Given:
- time1: the time to collect the first 500 mL of water = 24 seconds
- time2: the time to collect the second 500 mL of water = 32 seconds
- volume1: the volume of the first 500 mL sample
- volume2: the volume of the second 500 mL sample

Since the filtration continued for a total of 15 minutes before the second sample was collected, we know that the total volume of water filtered is 500 mL + 500 mL = 1000 mL.

To find the volume of the first sample, we can subtract the volume of the second sample from the total volume:
volume1 = total volume - volume2 = 1000 mL - 500 mL = 500 mL

Now we have all the necessary values to calculate the SDI:
SDL = (32 s - 24 s) / (500 mL - 500 mL)
SDL = 8 s / 0 mL

Since we have a division by 0, the SDI is undefined in this case.

Learn more about SDL from the above link :

https://brainly.com/question/15161660

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