Sludge Drying Process Calculation

Question:

If a sludge containing 70% water and 30% solids is passed through a drier and the resulting product contains 25% water, how much water is evaporated per ton of sludge sent to the drier?

a) 45% of water is evaporated

b) 50% of water is evaporated

c) 60% of water is evaporated

d) 75% of water is evaporated

Final answer: The amount of water evaporated per ton of sludge sent to the drier is 45%.

Answer:

The amount of water evaporated per ton of sludge sent to the drier is 45%.

To determine the amount of water evaporated per ton of sludge sent to the drier, we need to calculate the difference in water content before and after drying. The initial sludge contains 70% water, which means it contains 70% of 1 ton or 0.7 tons of water. The remaining 30% represents the solids, which is 0.3 tons. After drying, the resulting product contains 25% water. This means it contains 25% of 1 ton or 0.25 tons of water. The remaining 75% represents the solids, which is 0.75 tons.

To calculate the amount of water evaporated, we subtract the final water content from the initial water content:

0.7 tons - 0.25 tons = 0.45 tons of water evaporated.

Therefore, 45% of water is evaporated per ton of sludge sent to the drier.