An analyst reports that the belt press sludge cake is 17% solids. How many mg/L does this correspond to?

To understand why the answer is 170,000 mg/L when the belt press sludge cake contains 17% solids, it’s essential to convert the percentage of solids into a concentration measured in milligrams per liter (mg/L).

The percentage of solids refers to the weight of the solids in a given weight of the total sludge cake. To translate that into a mg/L measurement, one can use the following logic:

1. A 17% solids content indicates that there are 17 grams of solids for every 100 grams of the sludge cake.

2. Since 1 gram is equal to 1,000 milligrams, 17 grams translates to 17,000 milligrams of solids in 100 grams of sludge cake.

3. When this is converted to a per-liter basis, it is important to recognize that 100 grams of sludge is equivalent to 100 milliliters of water. But for the purpose of concentration, we look at milligrams of solids in 1 liter of water (1,000 milliliters).

4. Scaling this up, since 100 grams corresponds to 0.1 liters, to find how many mg/L it corresponds to in a full 1,000 milliliters (1 liter