Answer :
To calculate the Mean Cell Residence Time (MCRT), we can use the formula:
\[ MCRT = \frac{V}{Q} \]
Where:
- \( MCRT \) = Mean Cell Residence Time (in days)
- \( V \) = Volume of Aeration Tank (in gallons)
- \( Q \) = Waste Activated Sludge (WAS) flow rate (in gallons per day)
Given:
- Volume of Aeration Tank (\( V \)) = 1.5 million gallons = 1,500,000 gallons
- Waste Activated Sludge (WAS) flow rate (\( Q \)) = 65,000 gallons per day
We can now plug these values into the formula to find the MCRT:
\[ MCRT = \frac{1,500,000 \text{ gallons}}{65,000 \text{ gallons/day}} \]
\[ MCRT = \frac{1,500,000}{65,000} \text{ days} \]
\[ MCRT ≈ 23.08 \text{ days} \]
So, the Mean Cell Residence Time (MCRT) is approximately 23.08 days.
