What is the daily amount of aluminum sulfate needed if a plant treats 9 MGD with a desired feed rate of 20 mg/L?

To determine the daily amount of aluminum sulfate needed for a plant treating 9 million gallons per day (MGD) at a desired feed rate of 20 mg/L, you can use the following steps and calculations:

1. Convert the flow rate from million gallons per day to gallons per day:

• 9 MGD = 9,000,000 gallons per day.

2. Calculate the total amount of aluminum sulfate required in milligrams:

• The feed rate is given as 20 mg/L. Since there are 1,000 liters in a cubic meter and approximately 3.78541 liters in a gallon, we can calculate the total daily requirement in milligrams:

[

\text{Total mg per day} = (\text{Flow in gallons}) \times (\text{Convert gallons to liters}) \times (\text{Feed rate in mg/L})

]

• Converting 9,000,000 gallons to liters:

[

9,000,000 \text{ gallons} \times 3.78541 \text{ L/gallon} \approx 34,068,000 \text{ liters}

]

• Now, applying the feed rate