Process And Control Of Water And Wastewater Treatment

Front 1

What effect will the addition of lime, caustic soda, or soda ash have on the pH of water?

Back 1

Increase.

Front 2

Which elements cause hardness in water?

Back 2

Calcium and Magnesium.

Front 3

A major factor that leads to reservoir turnover is:

Back 3

The upper strata becoming more dense and sinking to the bottom.

Front 4

The Maximum Contaminant Level (MCL) means:

Back 4

The maximum allowable level of a given contaminant in drinking water.

Front 5

Which element does Ion Exchange Softening increase in the finish water?

Back 5

Sodium.

Front 6

Kjeldahl nitrogen refers to:

Back 6

Total Nitrogen (TN) --

organic plus ammonia nitrogen.

Front 7

Which treatment technology can be utilized to achieve compliance with a Volatile Chemical Maximum Contaminant Level?

Back 7

Powdered activated carbon slurry.

Front 8

What factor can create demand for more DO (dissolved oxygen which can be provided through increased aeration) in an aeration basin?

Back 8

Increased BOD in the influent.

Front 9

The first step in Anaerobic Sludge Digestion is:

Back 9

Acid formation.

Front 10

The best solution for an operator of a wastewater treatment plant to correct a problem:

Back 10

Reduce wasting of sludge to the digester.

Front 11

The common rate of filtration for a rapid sand filter is described in gallons per square foot per minute, what is the filtration rate?

Back 11

2 to 6 GPM.

Front 12

What type of treatment will the lime, caustic soda, or soda ash render on raw water?

Back 12

Softening.

Front 13

A primary source of volatile organic chemical contamination of water supplies is:

Back 13

Industrial solvents.

Front 14

Three of the most commonly used coagulants in water treatment are:

Back 14

Aluminum sulfate, ferric acid, and ferrous sulfate.

Front 15

In order for a chemical to function satisfactory as a coagulant, it must:

Back 15

React with the alkalinity in the water causing floc formation.

Front 16

Chlorine is most commonly used in water treatment for:

Back 16

Disinfection.

Front 17

Aeration in water treatment plants is utilized to:

Back 17

Reduce concentrations of dissolved gases.

Front 18

pH is a measure of:

Back 18

Hydrogen ion activity.

Front 19

This happens in the stabilization tank in an activated sludge wastewater treatment plant operating the contact stabilization mode:

Back 19

Absorption of waste material by microorganisms.

Front 20

A pH below 6.5 in treated water indicates what?

Back 20

That the water tends to be corrosive.

Front 21

In an activated sludge wastewater treatment plant when the oxygen levels in the aeration basin decrease (and the aerators are not the problem) the most probable cause is:

Back 21

The organic load increase.

Front 22

What is not monitored in raw influent wastewater?

Back 22

Fecal coliforms.

Front 23

_____ is the modification of the conventional activated sludge process. In this process two aeration tanks are used. One tank is for separate re-aeration of the return sludge for at least 4 hrs. before it is permitted to flow into the other aeration tank to be mixed with the primary effluent requiring treatment.

Back 23

Contact stabilization.

Front 24

The correction that is necessary to be made in an activated sludge wastewater treatment plant where the sludge is too young would be to:

Back 24

Increase the MLSS (mixed liquor suspended solids in the aeration basin.

Front 25

_____ is an instrument generally used to measure the color intensity of a chemical solution.

Back 25

Spectrophotometer.

Front 26

Is a pH of 3 considered to be acidic in wastewater?

Back 26

Yes.

Front 27

The term surface water runoff refers to:

Back 27

Water that flows into rivers after a rainfall.

Front 28

In a properly operating facultative pond utilized for wastewater treatment, the algae lives on carbon dioxide, sunlight, and nutrients during the day and at night the levels of carbon dioxide increases. This process has what effect on the pH of the water in the pond?

Back 28

The pH increases during the day and it decreases at night.

Front 29

Sedimentation is a process that ____ suspended particles from the water.

Back 29

Settles.

Front 30

____ are a group of motile microscopic animals that sometimes cluster into colonies and often consume bacteria an energy source.

Back 30

Protozoa.

Front 31

One cubic foot of water weighs:

Back 31

62.4 pounds.

Front 32

The purpose of primary sedimentation is to remove:

Back 32

Settleable and floatable material.

Front 33

If the raw water's turbidity changes from 10 NTUs to 300 NTUs and the finish water's turbidity increases from .1 NTUs to 1.0 NTUs, then the unit process having the most impact to correct the situation is

Back 33

Coagulation .

Front 34

The water table is defined as the:

Back 34

Upper surface of the groundwater.

Front 35

Coliform bacteria are:

Back 35

Indicator organisms.

Front 36

Sand, grit, and silt are composed of what kind of matter?

Back 36

Inorganic.

Front 37

The primary origin of coliforms in the water supply is:

Back 37

Fecal contamination by warm-blooded animals.

Front 38

Water weighs:

Back 38

8.34 lbs/gallon

Front 39

One cubic foot of water weighs:

Back 39

62.4 lbs

Front 40

One cubic foot will hold:

Back 40

7.48 gallons of water

Front 41

Water contaminants may be:

Back 41

Physical, Chemical, Biological, and Radiological

Front 42

Physical contaminants in water are:

Back 42

Color, Turbidity, Odors, Taste, and Temperature

Front 43

Color:

Back 43

Is a result of dissolved organic material.

Front 44

Plants strive to keep the turbidity of finish water between:

Back 44

0.05 - 0.3 units

Front 45

The presence of color in water is :

Back 45

Aesthetically objectionable.

Front 46

Amber color water indicates:

Back 46

The presence of acid waters from mine drainage as well as humic substances that can later form into trihalomethanes.

Front 47

Taste in water may be caused by:

Back 47

Minerals, and algal growth.

Front 48

Phenolphthalein:

Back 48

The alkalinity in a water sample measured by the amount of standard acid required to lower the pH to a level of 8.3 as indicated by the change in color, from pink to clear. It is expressed as mg/L of equivalent calcium carbonate.

Front 49

Grab Sample:

Back 49

A single sample of water collected at a particular time and place, which represents the composition of the water only at that time and place.

Front 50

Continuous Sample:

Back 50

A flow of water from a particular place in a plant to the location where samples are collected for testing.

Front 51

Representative Sample:

Back 51

A sample portion of material or water that is nearly identical in content and consistency as possible to that in the larger body of water being sampled.

Front 52

Composite Sample:

Back 52

A sample that is a collection of individual samples obtained at regular intervals, usually every one to two hours during a 24-hour time span.

Front 53

Absorption:

Back 53

The taking in or soaking up of one substance into the body of another by molecular or chemical action.

Front 54

Adsorption:

Back 54

The gathering of a gas, liquid, or dissolved substance on the surface or interface zone of another material.

Front 55

Aeration:

Back 55

The process of adding air to water. Air can be added to water by either passing air through water or passing water through air.

Front 56

Acidic:

Back 56

The condition of water, which contains a sufficient amount of acid substances to lower the pH below 7.0

Front 57

Aliquot:

Back 57

A portion of a sample; often an equally divided portion of a sample.

Front 58

Aerobic Digestion:

Back 58

The breakdown of wastes by microorganisms in the presence of dissolved oxygen.

*This is an extension of the activated sludge process.

Front 59

Anaerobic Digestion:

Back 59

Wastewater solids and water are placed in a large tank where bacteria decompose the solids in the absence of dissolved oxygen.

Front 60

Alkalinity:

Back 60

The capacity of water to neutralize acids. This capacity is caused by the waters content of carbonate, bicarbonate, hydroxide, and occasionally borate, silicate, and phosphate.

Front 61

Alkalinity is expressed in:

Back 61

Milligrams per Liter of Equivalent Calcium Carbonate.

Front 62

Buffer Capacity:

Back 62

A measure of the capacity of a solution or liquid to neutralize acids or bases.

* This is a measure of the capacity of the water for offering a resistance to changes in pH.

Front 63

Calcium Carbonate Equivalent:

Back 63

An expression of the concentration of specified constituents in the water in terms of their equivalent value to calcium carbonate.