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Flashcards in Dryers Deck (19)
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1
Q

Relative Humidity

A
  • the comparison of the amount of water a sample of air holds to the maximum amount it could hold if saturated (think %)
  • the higher the temperature the lower the relative humidity because hotter air can hold more water
2
Q

Dew point

A
  • the temperature to which a gas must be reduced before the water vapour it carries begins to condense
  • affected by both temperature and pressure. Increasing temperature doesn’t increase the dew point but increases the gap between when you will reach the dew point, increasing pressure decreases the dew point
3
Q

Dew point depression

A

-lowering the dew point

4
Q

Types of dryers

A
  • adsorption (physical)
  • absorption (chemical)
  • refrigeration
  • mechanical
5
Q

4 Types of desiccant

A
  • activated alumina
  • granulated silica gel
  • bead type modified silica gel
  • molecular sieves (acts as a filter and restricts the size of molecules that are allowed to pass-used with hydrocarbons, nitrogen, hydrogen)
6
Q

Regeneration for heatless

A

-uses 10-15% of regenerated pressure

7
Q

What measures if your desiccant is full or breaking down?

A

-hydrometer

8
Q

Two types of Absorption dryers

A
  • chemical (uses Deliquescents and can’t be regenerated)

- liquid dehydration (uses glycol and the glycol can be regenerated)

9
Q

Deliquescents

A
  • calcium chloride, salts or urea

- dissolve as they combine with the moisture they are absorbing

10
Q

Liquid Dehydration Dryer

A
  • the glycol can be regenerated at 98%

- can lower the dew point of a gas by 40-60 degrees from when it enters the dryer

11
Q

Latent heat

A
  • heat required to create a change of state like ice to water, water to steam
  • uses more heat energy because it requires additional heat to keep changing the state after it reaches the boiling state.
12
Q

Sensible heat

A
  • heat you can measure as its changin

- until it reaches its boiling point

13
Q

Coalescing filters

A
  • remove oil and water in the form of aerosols too small to be captured by regular filters before they can get to the desiccant bed
  • Used pre filters before the inlet as well as downstream
14
Q

Rotary drum (MD)

A

-25% of the desiccant pad is regenerated at the same time as the 75% of the air is dried.

15
Q

Refrigeration Dryer

A

-least expensive method of dew point depression.

16
Q

Mechanical Dryers

A
  • liquid separators (least complicated)
  • Centrifugal separators (after an after cooler)
  • demister pads
  • over compression (only mechanical method that can lower the dew point)
  • coalescing filters
17
Q

Liquid separator

A

-least complicated of the mechanical

-

18
Q

Centrifugal Separator

A

-

19
Q

Demister Pads

A

-