Introduction to Water Treatment 060401e

Question 1

Where does essentially all of the fresh water supply come from?

Answer 1

Precipitation that falls on the land areas

Question 2

The quantitative capacity of a water or water solution to neutralize an acid?

Answer 2

Alkalinity

Question 3

The process of adding oxygen to water for oxidation of matter such as iron or to cause the release of dissolved gases such as dioxide or hydrogen sulphide from water

Answer 3

Aeration

Question 4

The process in which beds of a filter or ion exchange media are subjected to flow opposite service flow direction to loosen the bed and to flush suspended matter collected during the service run to waste

Answer 4

Backwash

Question 5

What elements when dissolved causes hardness in water?

Answer 5

Calcium and magnesium

Question 6

What term is often used interchangeably with demineralization?

Answer 6

Deionization

Question 7

One grain per US gallon is equal to how many milligrams per litre or parts per million?

Answer 7

17.1 mg/l or ppm

Question 8

One grain per imperial gallon equals how many milligrams or ppm?

Answer 8

14.3

Question 9

Trade name for a particular type of air induction or injector valve

Answer 9

Hydrocharger

Question 10

A reversible process in which ions are released from an insoluble permanent material in exchange for other ions in a surrounding solution

Answer 10

Ion exchange

Question 11

What is used to regenerate a manganese greensand filter?

Answer 11

Potassium permanganate

Question 12

The percentage of TDS removed from the feed water

Answer 12

Rejection

Question 13

Any water that contains less than 1.0 gpg of hardness minerals expressed as calcium carbonate

Answer 13

Soft water

Question 14

The removal of calcium and magnesium, the ions with are the principal cause of hardness from water

Answer 14

Water softening

Question 15

Porous media where grains are not connected to each other are considered what?

Answer 15

Unconsolidated

Question 16

Media where the grains are cemented together is called what?

Answer 16

Consolidated

Question 17

Rocks in which the groundwater moves through cracks, joints and fractures in otherwise solid rock?

Answer 17

Fractured aquifer

Question 18

An aquifer that lies beneath layers of impermeable materials?

Answer 18

Confined aquifer or artesian aquifer

Question 19

Aquifers that are bounded by the water table?

Answer 19

Unconfined awuifer

Question 20

One of the most important changes in groundwater chemistry occurs where?

Answer 20

In the soil

Question 21

What kind of wells usually contain lower amounts of hardness and other dissolved materials?

Answer 21

Shallow wells

Question 22

What is the most common impurity in water?

Answer 22

Water hardness

Question 23

Hardness Minerals + Heat = ?

Answer 23

Scale

Question 24

Hardness Minerals + Soap = ?

Answer 24

Scum

Question 25

How do you convert part per million (ppm) to grains per US gallon?

Answer 25

Divide ppm by 17.1

Question 26

What are the 3 designations for the term hardness?

Answer 26

Total hardness Temporary hardness Permanent hardness

Question 27

Very hard water is unfit for human consumption unless it is softened by treatment to less than how many grains per gallon?

Answer 27

12 gpg

Question 28

It is recommended that hardness should not exceed how many gpg in household applications?

Answer 28

3.5

Question 29

What causes temporary water hardness?

Answer 29

Bicarbonates of calcium and magnesium dissolved in water cause temporary hardness (settle out at 140°F)

Question 30

What causes permanent hardness in water?

Answer 30

Carbonates of calcium and magnesium in addition to sulphates, nitrates and other chemicals (settle out at 299°F) When water is evaporated, this permanent hardness remains behind in the boiler because it will not vaporize

Question 31

What is point source water pollution?

Answer 31

When you know the cause and the point of origin

Question 32

What is non-point source water pollution?

Answer 32

When you don’t know what’s polluting the water source

Question 33

Clean rain has a pH value of what?

Answer 33

5.6

Question 34

Water with a hardness of 0.5 gpg would be considered what?

Answer 34

Soft