WTT Topic 5 Part 1 Introduction

Multiple Select

What are biological wastewater treatment processes commonly used for? (Choose all that applies)

• Remove carbon based contaminants in wastewater.

• Remove Sulfur based contaminants in wastewater.

• Remove Nitrogen based contaminants in wastewater.

• Remove salt based contaminants in wastewater.

Multiple Choice

What process is shown in this image?

• filtration

• sediments

• flocculation

• disinfection

Multiple Choice

The Preliminary treatment of wastewater

• uses microorganisms to eat the organic material

• removes large objects with a bar screen and grit chamber

• uses chemicals to disinfect and kill pathogens

• Thickens and dewaters the sludge

Multiple Choice

Why are aggregate terms such as BOD, COD, TOC used to measure the organic contaminants in wastewater?

• There are too many different types of carbon based contaminants that can cause water to be polluted.

• Using aggregate terms allows more reliable detection of contaminants in wastewater.

• Measure BOD is a quick and effective method that only takes minutes to complete.

• TOC measures the total organic carbon content of wastewater and is most applicable in wastewater analysis.

Multiple Choice

Identify the FALSE statement.

• BOD and COD are commonly used to detect the organic contaminant level of wastewater.

• Total Nitrogen consists of organic and inorganic Nitrogen.

• Compared to COD, BOD measurement detects the biodegradable portion in wastewater.

• Compared to COD, BOD measurements are quicker and more reproducible.

Multiple Choice

BOD5 measures the 5 most difficult to digest organic contaminant while BOD20 measures the 20 most difficult to digest organic contaminant. Hence, BOD20 is more comprehensive. Is this statement true or false?

• TRUE

• FALSE

Multiple Choice

Identify the FALSE statement regarding COD measurement.

• COD measures the amount of oxygen required for the chemical oxidation of organics to carbon dioxide and water.

• COD is fast and reproducible.

• In COD measurement, dissolved oxygen in the wastewater sample is not consumed as organic contaminants are oxidized by chemical agents.

• COD only measures the non-biodegradable fraction of organic contaminants in wastewater.