D2L quiz questions

Question 1

The amount of moisture contained in an air volume compared to the maximum amount that it could hold at saturation is known as:

Answer 1

Relative Humidity

Question 2

What is the primary purpose of a coalescing filter?

Answer 2

To remove oil from air flow.

Question 3

Reactivation of liquid dehydration dryers is accomplished by:

Answer 3

Heating the glycol in a still.

Question 4

What dryer provides the lowest dew point?

Answer 4

Desiccant dryer
also know as Adsorption Dryer, dew point as low as -70C

Question 5

Desiccant dryers are also known as:

Answer 5

Adsorption Dryers

Question 6

What are dryer pre-filters used to trap?

Answer 6

Solid contaminants and Oil

Question 7

The air leaving the evaporator in a refrigeration dryer has a dew point of 2 degrees C. What is the dew point after it leaves the air to air exchanger and exits the dryer?

Answer 7

Equal to 2 degrees C

Question 8

Absorption type dryers use a chemical bond between the drying agent and the gas stream. What absorption dryers use a consumable deliquescent?

Answer 8

Chemical Dryers

Question 9

What is the name for the temperature at which water vapour will condense to a liquid?

Answer 9

Dewpoint

Question 10

As air is heated, its ability to hold water vapour will:

Answer 10

Increase

Question 11

What desiccant is commonly used in adsorption dryers?

Answer 11

Activated Alumina

Question 12

Flow rates which exceed the stated capacity of a dryer will result in:

Answer 12

Poor dew point reduction

Question 13

After air leaves the aftercooler, any further reduction of temperature will result in:

Answer 13

Condensation

Question 14

What is installed to prevent oil contamination of the desiccant in an adsorption dryer?

Answer 14

Coalescing pre-filters

Question 15

What dryer does water vapour adhere to the surface of a desiccant?

Answer 15

Adsorption dryer

Question 16

The desiccants found in air dryers can be:

Answer 16

Regenerated

Question 17

How does an increase in the temperature of a given volume of air affect its dew point?

Answer 17

It is unaffected

Question 18

What sequence of heat exchangers does the compressed air flow through in a refrigerated dryer?

Answer 18

Air to air - evaporator - air to air

Question 19

What dryer uses glycol as a drying agent and has a still for regenerating the glycol?

Answer 19

Liquid Dehydration

Question 20

In an absorption dryer a deliquescent changes from?

Answer 20

a solid to a liquid(brine)

Question 21

The limitation of the adsorption dryer is the amount of moisture the media can hold. What is done to overcome this limitation?

Answer 21

Regeneration

Question 22

What can cause an increased pressure drop across a desiccant dryer:

Answer 22

The desiccant breaking down

Question 23

Chemical dryers use deliquescent materials that slowly ______ and cannot be _______.

Answer 23

Dissolve, and cannot be Regenerated

Question 24

What type of dryer is designed to lower the dewpoint to 2 or 3° C?

Answer 24

Refrigerant

Question 25

Who must install a lock while performing maintenance tasks?

Answer 25

All persons involved in the maintenance.

Question 26

What method is used to remove liquids and solids from the gas stream upstream of a gas compressor?

Answer 26

Reduction in velocity / change in direction of gas

Question 27

The four main categories of dryers are:

Answer 27

Mechanical, Refrigeration(cooling), adsorption and absorption.

Question 28

What are the steps in a heated regeneration desiccant dryer cycle in the correct order?

Answer 28

Drying, regeneration, cooling

Question 29

A refrigeration dryer has two flow paths. They are:

Answer 29

The compressed air circuit and the refrigerant circuit

Question 30

On an adsorption MD type dryer, what gas is used for regeneration?

Answer 30

Compressed air from upstream of the aftercooler

Question 31

Heatless dryers rely on what (%) portion of the dry gas flow being circulated through the bed to be regenerated.

Answer 31

15%

Question 32

Check __________ differential for an increase indicates time to changed out filters

Answer 32

Pressure differential

Question 33

Demister pads are used where?

Answer 33

Outlet/exit of process vessels
(Can be found after glycol contractor on liquid dehydration dryer)