Adding alum as a coagulant primarily affects which parameter?

Prepare for the ADEQ Water Treatment Grade 4 Test. Study with flashcards and multiple-choice questions, with each question offering hints and explanations. Ace your exam!

Multiple Choice

Adding alum as a coagulant primarily affects which parameter?

Explanation:
Alum as a coagulant primarily affects the surface charge of particles, or zeta potential. The aluminum ions neutralize the negative charges on colloidal particles, reducing electrostatic repulsion between them. With this charge neutralized, particles can come together more easily to form larger flocs that settle out, which is the central way alum helps clarify water. Temperature, dissolved oxygen, or direct turbidity changes aren’t the primary targets of alum addition—the practical outcome is achieved by destabilizing particle charges and promoting floc formation that reduces turbidity.

Alum as a coagulant primarily affects the surface charge of particles, or zeta potential. The aluminum ions neutralize the negative charges on colloidal particles, reducing electrostatic repulsion between them. With this charge neutralized, particles can come together more easily to form larger flocs that settle out, which is the central way alum helps clarify water. Temperature, dissolved oxygen, or direct turbidity changes aren’t the primary targets of alum addition—the practical outcome is achieved by destabilizing particle charges and promoting floc formation that reduces turbidity.

Subscribe

Get the latest from Passetra

You can unsubscribe at any time. Read our privacy policy