Massachusetts Wastewater Practice Exam

Why must lime slurry mixing equipment and pumps be kept clean at all times?

1. Because meters will fog up

2. Because the lime should not be wet

3. Because lime slurry is sticky and material may gum and stick

4. All of the above

The correct answer is: Because lime slurry is sticky and material may gum and stick

Maintaining clean lime slurry mixing equipment and pumps is essential primarily because lime slurry is inherently sticky. When lime comes into contact with residual material from previous batches or other contaminants, it can cause the slurry to gum up and adhere to the equipment. This gumming can lead to clogs, decreased efficiency, and difficulty in operation, ultimately affecting the quality of the wastewater treatment process. In addition to the stickiness, keeping equipment clean prevents buildup that could harbor bacteria or alter chemical compositions, ensuring that the equipment performs optimally. By avoiding these complications, operators can maintain consistent mixing and pumping of lime slurry, ensuring effective treatment results. Therefore, the emphasis on cleanliness addresses both operational efficiency and the integrity of the treatment process.