Question

In domestic sewage, suspended solids, colloidal and dissolved materials constitute

• A. $10\%$
• B. $5.6\%$
• C. $2.7\%$
• D. $0.1\%$

Answer 1

The correct option is D $0.1\%$

The wastewater mixture will contain large numbers of microscopic organisms, mostly bacteria that are capable of consuming the organic component (fats, proteins, and carbohydrates) of the mixture and bringing about rapid changes in the wastewater. The solid components of wastewaters actually represent a very small part of most discharges, usually less than 0.1% by weight. However, it is this small component of the wastewater that presents the major challenges in wastewater treatment, operation, and disposal.

So the correct answer is '0.1%'.