absorption

Question 1

When the two contacting phases are a gas and a liquid, the unit operation is called ?

Answer 1

Absorption

Question 2

are absorbed from the gas phase into a liquid phase in absorption.

Answer 2

Solute

Question 3

This process involves molecular and turbulent diffusion or mass transfer of solute A through a stagnant non-diffusing gas B into a stagnant liquid C.

Answer 3

Absorption

Question 4

General Types of Gas Absorption Equipment (3)

Answer 4

-Plate Towers
-Structure Packing
-Random Packing

Question 5

To efficiently bring the vapor and liquid intro contact in the absorption tower

Answer 5

Plate Towers

Question 6

Organized and geometrically designed elements, often stacked in a uniform way.

Answer 6

Structure Packing

Question 7

Loose filling of a container with shapes like rings, spheres, or saddles. Installation involves simply pouring the packing material into the column.

Answer 7

Random Packing

Question 8

Examples include mesh pads or specific shapes like discs with honeycombs.

Answer 8

Structure Packing

Question 9

Plate Towers is also called?

Answer 9

Tray Towers

Question 10

are designed to provide liquid holdup in order to achieve the proper vapor-liquid mass transfer that the distillation process requires for separation.

Answer 10

Tray Towers

Question 11

Holdup is accomplished using a ——————– on each tray?

Answer 11

weir

Question 12

flow across the trays allows ———– moving vapors and ————– moving liquids to have intimate contact in strategically placed passages in the tray.

Answer 12

upward and downward

Question 13

Types of Tray (Plate) Towers (3)

Answer 13

-valve trays
-bubble cap trays
-sieve trays

Question 14

are perforated plates with holes or slots that allow vapor to pass through. They typically have a larger open area compared to bubble cap trays, which allows for more vapor to pass through and interact with the liquid on the tray.

Answer 14

Sieve trays

Question 15

feature perforated plates with movable valves or caps that open and close in response to the vapor flow. This movement helps to control the flow of vapor and liquid, promoting better contact and separation efficiency.

Answer 15

valve tray

Question 16

consist of perforated plates with cylindrical caps that allow vapor to pass through the liquid on the tray. The caps help to evenly distribute the vapor and create bubbles, which enhances the contact between the vapor and liquid for efficient separation.

Answer 16

bubble cap tray

Question 17

are more suitable for low capacity operations

Answer 17

packed columns

Question 18

are particularly useful in the field of vacuum distillation

Answer 18

packed columns

Question 19

For separating heat sensitive materials ——————- are useful because the liquid hold up is low

Answer 19

packed columns

Question 20

when corrosion is a problem, the only solution is?

Answer 20

packing

Question 21

Pressure drop per unit length is less.

Answer 21

packed columns

Question 22

Types of Structure Packing (3)

Answer 22

-knitted Wire STructured Packing
-gauze
-corrugated structured packing

Question 23

multitude of small wires, offer a large surface area and efficient mass transfer.

Answer 23

Knitted Wire Structured Packing

Question 24

can be formed into other shapes, such as rolled into cylinders or wrapped to form a solid block.

Answer 24

KNitted wire structured packing

Question 25

is used for applications that require the low

Answer 25

gauze

Question 26

It is ideal for processing pharmaceuticals and other chemicals that require a specific temperature range.

Answer 26

gauze

Question 27

a type of tray tower that are high in capacity, turndown ratio, and efficiency

Answer 27

valve tray

Question 28

a type of tray tower that are high in pressure drop and entrainment.

Answer 28

bubble cap tray

Question 29

a type of tray tower that are high in efficiency alone and cheapest.

Answer 29

sieve tray

Question 30

Sheet metal is often used in applications such as vacuum distillation and high-pressure absorption. Because it is stronger and more durable than knitted packing and gauze.

Answer 30

corrugated structured packing

Question 31

it can process much higher volumes of liquid and vapor.

Answer 31

corugted structured packing

Question 32

its smooth, open surface has some resistance to chemical fouling. This quality makes these types of packing ideal for wastewater and other fouling-prone environments.

Answer 32

corrugated structured packing

Question 33

is used to increase surface area for vapor/liquid contact so that chemical separation is more efficient.

Answer 33

random packing

Question 34

The small pieces of random packing in an absorption column are designed to form a ?

Answer 34

large surface area

Question 35

is designed to maximize the surface-to-volume ratio and minimize pressure drop.

Answer 35

random packing

Question 36

The efficacy of random packaging depends upon a few factors (3)

Answer 36

-efficiency -pressure drop -capacity

Question 37

in random packing, ------------------- pressure drop is ideal because high pressure drop diminishes both performance and efficiency.

Answer 37

low

Question 38

random packing materials were made of ?

Answer 38

ceramic

Question 39

today, random packing are made of?

Answer 39

metal and plastic, with some other used in specialized applications

Question 40

types of Random Packing (5)

Answer 40

-Raschig Rings -Pall Rings -saddle rings -lessing rings -tri-packs

Question 41

makes use of small pieces of tube to make a packing bed. These small tubes are usually about as long as they are wide.

Answer 41

raschig rings

Question 42

belong to an earlier, less sophisticated generation of packing material. They are smooth, without holes, grooves, ribbing or other textured elements. They have low capacity and low efficiency, and they tend to cost more than other types of random packing.

Answer 42

raschig rings

Question 43

have such high cost in comparison to their efficacy, applications for this type of packing are limited.

Answer 43

raschig rings

Question 44

In situations where corrosive material is being separated, however, ceramic material for this type of rings are effective thanks to their high corrosion-resistance.

Answer 44

raschig rings

Question 46

are similar to Raschig rings but come with added sophistication.

Answer 46

pall rings

Question 47

include added internal support structures and external surfacing. The texture within the ring walls allows for points of internal dripping that significantly increase the capacity and the efficiency of the packing.

Answer 47

pall rings

Question 48

work particularly well for distillation and absorption applications.

Answer 48

pall rings

Question 49

come in two primary types — Berl saddles and Intalox® saddles.

Answer 49

saddle rings

Question 50

As their name suggests, they’re shaped like tiny saddles. They differ from Raschig and Pall rings in that their length exceeds their diameter.

Answer 50

saddle rings

Question 51

are often shorter, with a more traditional saddle shape.

Answer 51

smooth berl saddles

Question 52

are significantly longer, shaped much like pieces of macaroni halved lengthwise into long, open curved pieces. They also offer small holes and grooves for increased surface area and contact opportunity.

Answer 52

intalox saddles

Question 53

with their increased surface area for liquid and vapor contact, offer increased capacity and efficiency. They are ideal for chemical distillation, stripping and absorption.

Answer 53

saddle rings

Question 54

are made of ceramic. They have internal partitions to increase surface area and enhance efficiency. Like all ceramic packing pieces, they are highly resistant to heat and corrosion. These qualities make them ideal for applications such as regenerative oxide systems.

Answer 54

lessing rings

Question 55

were first developed in the late 70s and are now broadly used. 

Answer 55

tri-packs

Question 56

offer many advantages over older types of packings.

Answer 56

tri-packs

Question 57

Thanks to their spherical shape, they are not prone to nesting and settling. The interior ribs also maximize surface area and wetting qualities. To achieve low pressure drop and high-mass transfer rates.

Answer 57

tri-packs

Question 58

are commonly offered in a range of plastics, providing corrosion and temperature resistance. 

Answer 58

tri-packs

Question 59

a type of column which is high in capacity, large in diameter, less expensive, easier to maintain, less vapor liquid contact, available sie stream.

Answer 59

tray column

Question 60

a type of column which is low in capacity, small in diameter, expensive, difficult to maintain, and have more vapor liquid contact.

Answer 60

packed column

Question 61

a type of column who have high pressure drop and can handle high temperature, not safe for toxic and flammable liquids, appropriate for fouling liquids, and not reccomended for foaming systems.

Answer 61

tray column

Question 62

a type of column who have lower pressure drop and cannot handle high temperature, safe for toxic and flammable liquids, not appropriate for fouling liquids, and reccomended for foaming systems.

Answer 62

packed column

Question 63

no liquid flow

Answer 63

dry packing

Question 64

the pressure drop is similar to that of dry packings.

Answer 64

at low to moderate velocity

Question 65

the gas starts to hinder the liquid downflow, and local accumulations or pools of liquid start to appear in the packing

Answer 65

loading point

Question 66

Upper limit to the rate of gas flow

Answer 66

flooding point

Question 67

the liquid flows downward through the packing

Answer 67

low gas velocity

Question 68

For optimum design, the recommended gas velocity is --------------% of the gas flooding velocity

Answer 68

50-70%