4BE3 U6 C1 Obj 5 EMH

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

EASY What happens to the steam in the condenser section of a deaerator?

It is used to control the pressure

It is used to heat the water

It condenses and falls back into the deaerator (correct)

It is vented to the atmosphere

What is the purpose of the steam pressure controller?

To regulate the steam flow (correct)

To vent the gases to the atmosphere

To heat the water

To control the level of water in the deaerator

What is the function of the overflow valve?

To regulate the water level (correct)

To control the pressure in the deaerator

To heat the water

To vent the gases to the atmosphere

What is the purpose of the level alarm low?

To indicate low water level Signup and view all the answers

How does a tray-type deaerator work?

By trickling water down over a series of trays Signup and view all the answers

What is the purpose of the internal vent condenser?

To condense the steam and remove gases Signup and view all the answers

What is the function of the steam flow gauge?

To measure the steam flow Signup and view all the answers

What is the purpose of the safety valve?

To prevent overpressure Signup and view all the answers

How does a bubbling tray deaerator work?

By forcing steam up through perforated panels Signup and view all the answers

What is the function of the level control valve?

To control the water level Signup and view all the answers

What happens to dissolved gases in water as the temperature rises?

Their solubility decreases Signup and view all the answers

Why are deaerators used in boiler feedwater systems?

To remove dissolved gases from the water Signup and view all the answers

What is the purpose of scrubbing the water with steam in a deaerator?

To help sweep away released gases Signup and view all the answers

What is the effect of increasing temperature on the solubility of dissolved gases in water?

It decreases the solubility Signup and view all the answers

What is the purpose of the trays in a tray-type deaerator?

To increase the surface area of the water Signup and view all the answers

What is the difference between a tray-type and spray-type deaerator?

The method of water-steam contact Signup and view all the answers

What is the purpose of the spray nozzles in a spray-type deaerator?

To break up the water into small particles Signup and view all the answers

What is the result of not removing dissolved gases from boiler feedwater?

Corrosion of the boiler Signup and view all the answers

MEDIUM What is the primary benefit of increasing the surface area of the water in a deaerator?

To promote greater water-steam contact and improve degassing efficiency Signup and view all the answers

What is the role of turbulence in a deaerator?

To ensure efficient mixing in support of gas scrubbing Signup and view all the answers

What happens to the oxygen and carbon dioxide in the deaerator?

They are vented to the atmosphere Signup and view all the answers

What is the effect of residence time on a deaerator's efficiency?

It increases the efficiency of the deaerator Signup and view all the answers

What is the purpose of the condenser section in a deaerator?

To condense and vent the steam Signup and view all the answers

What is the function of the Level Control Valve?

To control the water flow Signup and view all the answers

What is the purpose of heating the water in a deaerator?

To reduce the solubility of dissolved gases Signup and view all the answers

Which of the following is a key difference between a tray-type and spray-type deaerator?

The method of increasing the surface area of the water Signup and view all the answers

What is the purpose of the steam in a deaerator?

To scrub the water and remove dissolved gases Signup and view all the answers

What is the difference between an internal vent condenser and an external vent condenser?

One is mounted inside the deaerator vessel and the other is mounted outside Signup and view all the answers

What is the result of removing dissolved gases from boiler feedwater?

Reduced corrosion in the boiler Signup and view all the answers

Why is it important to vent the released gases from the deaerator?

To prevent the released gases from re-dissolving in the water Signup and view all the answers

What is the purpose of the combination deaerator?

To combine the spray and tray principles Signup and view all the answers

What is the purpose of combining the steam flow with the water in a deaerator?

To create turbulence and promote efficient mixing Signup and view all the answers

What is the effect of increasing the water temperature in a deaerator?

It decreases the solubility of dissolved gases Signup and view all the answers

What is the purpose of the perforated panels in a bubbling tray deaerator?

To force steam up through the water Signup and view all the answers

What is the purpose of the safety valve in a deaerator?

To prevent overpressure in the deaerator Signup and view all the answers

What is the result of deaerating the water in a deaerator?

The water becomes less prone to corrosion and scaling Signup and view all the answers

What is the primary factor that affects the solubility of dissolved gases in water?

Temperature Signup and view all the answers

Which of the following operating parameters is not directly affected by the design of the deaerator?

Temperature Signup and view all the answers

What is the primary benefit of using a combination deaerator?

Flexibility in operation Signup and view all the answers

Which of the following is a disadvantage of the spray-type deaerator compared to the tray-type deaerator?

Lower surface area Signup and view all the answers

What is the primary purpose of the scrubber in a deaerator?

To remove dissolved gases Signup and view all the answers

What is the effect of increasing the residence time in a deaerator?

Increased efficiency Signup and view all the answers

Which of the following is a characteristic of the tray-type deaerator?

Increases the surface area of the water Signup and view all the answers

HARD What is the primary reason for venting the released gases from the deaerator?

To prevent corrosion Signup and view all the answers

What is the primary function of the steam in the deaerator during the heating process?

To increase the water temperature Signup and view all the answers

What is the purpose of the trays in a combination deaerator?

To increase the surface area of the water Signup and view all the answers

What is the effect of increasing the residence time in a deaerator?

It increases the deaeration efficiency Signup and view all the answers

What is the purpose of the internal vent condenser in a combination deaerator?

To condense the steam and vent the gases Signup and view all the answers

What is the role of the overflow valve in a deaerator?

To regulate the water flow Signup and view all the answers

What is the primary benefit of using a bubbling tray deaerator?

It increases the deaeration efficiency Signup and view all the answers

What is the purpose of the thermometer in a deaerator?

To measure the water temperature Signup and view all the answers

What is the effect of increasing the water temperature in a deaerator?

It decreases the solubility of dissolved gases Signup and view all the answers

What is the purpose of the safety valve in a deaerator?

To prevent overpressure in the deaerator Signup and view all the answers

What is the primary difference between an internal vent condenser and an external vent condenser?

The location of the condenser Signup and view all the answers

Study Notes

Boiler Feedwater Systems and Deaerators

Dissolved gases, such as oxygen and carbon dioxide, have lower solubility in water as the water temperature rises.
Deaerators are used to remove dissolved gases from boiler feedwater to prevent corrosion in boilers.

Deaerator Operating Parameters

Temperature: an increase in temperature reduces the solubility of dissolved gases.
Turbulence: steam flow ensures efficient mixing in support of gas scrubbing.
Surface Area: the use of trays increases the surface area of the water, which improves the degassing efficiency.
Time: a deaerator's efficiency is a function of the residence time.

Deaerator Configurations

Tray Type: inlet water is directed into a steam chamber, where it heats up and then cascades down several trays to increase the surface area of the water.
Spray Type: inlet water is broken up into small particles with spray nozzles to promote water-steam contact.

Deaerator Components and Control Mechanisms

Steam Supply
Steam Flow Gauge
Level Control Valve
Relief Valve
Level Alarm Low and Low-Low
Pressure Gauge
Air Vent
Condensate Safety Valve
Thermometer
Vent

Deaerator Process

Inlet water is heated and scrubbed with steam to release dissolved gases.
Released gases and steam are vented from the deaerator.
Degassed water is stored in the deaerator and withdrawn continuously as needed by the boiler feedwater pump.

Tray-Type Deaerator

Water flow is broken up by trickling down over a series of trays.
Entering steam scrubs the water in the lower trays and heats the water in the upper tray section.
Released gases and remaining steam pass to the internal vent condenser, where most of the steam is condensed and the gases are vented to atmosphere.

Combination Deaerator

Water is first sprayed into the upper heating section of the deaerator.
Then, it trickles over a series of steam-swept trays.
Released gases and remaining steam pass through the incoming water spray on their way to the vent opening, causing most of the steam to condense.

Boiler Feedwater Systems and Deaerators

Dissolved gases, such as oxygen and carbon dioxide, have lower solubility in water as the water temperature rises.
Deaerators are used to remove dissolved gases from boiler feedwater to prevent corrosion in boilers.

Deaerator Operating Parameters

Temperature: an increase in temperature reduces the solubility of dissolved gases.
Turbulence: steam flow ensures efficient mixing in support of gas scrubbing.
Surface Area: the use of trays increases the surface area of the water, which improves the degassing efficiency.
Time: a deaerator's efficiency is a function of the residence time.

Deaerator Configurations

Tray Type: inlet water is directed into a steam chamber, where it heats up and then cascades down several trays to increase the surface area of the water.
Spray Type: inlet water is broken up into small particles with spray nozzles to promote water-steam contact.

Deaerator Components and Control Mechanisms

Steam Supply
Steam Flow Gauge
Level Control Valve
Relief Valve
Level Alarm Low and Low-Low
Pressure Gauge
Air Vent
Condensate Safety Valve
Thermometer
Vent

Deaerator Process

Inlet water is heated and scrubbed with steam to release dissolved gases.
Released gases and steam are vented from the deaerator.
Degassed water is stored in the deaerator and withdrawn continuously as needed by the boiler feedwater pump.

Tray-Type Deaerator

Water flow is broken up by trickling down over a series of trays.
Entering steam scrubs the water in the lower trays and heats the water in the upper tray section.
Released gases and remaining steam pass to the internal vent condenser, where most of the steam is condensed and the gases are vented to atmosphere.

Combination Deaerator

Water is first sprayed into the upper heating section of the deaerator.
Then, it trickles over a series of steam-swept trays.
Released gases and remaining steam pass through the incoming water spray on their way to the vent opening, causing most of the steam to condense.

Boiler Feedwater Systems and Deaerators

Dissolved gases, such as oxygen and carbon dioxide, have lower solubility in water as the water temperature rises.
Deaerators are used to remove dissolved gases from boiler feedwater to prevent corrosion in boilers.

Deaerator Operating Parameters

Temperature: an increase in temperature reduces the solubility of dissolved gases.
Turbulence: steam flow ensures efficient mixing in support of gas scrubbing.
Surface Area: the use of trays increases the surface area of the water, which improves the degassing efficiency.
Time: a deaerator's efficiency is a function of the residence time.

Deaerator Configurations

Tray Type: inlet water is directed into a steam chamber, where it heats up and then cascades down several trays to increase the surface area of the water.
Spray Type: inlet water is broken up into small particles with spray nozzles to promote water-steam contact.

Deaerator Components and Control Mechanisms

Steam Supply
Steam Flow Gauge
Level Control Valve
Relief Valve
Level Alarm Low and Low-Low
Pressure Gauge
Air Vent
Condensate Safety Valve
Thermometer
Vent

Deaerator Process

Inlet water is heated and scrubbed with steam to release dissolved gases.
Released gases and steam are vented from the deaerator.
Degassed water is stored in the deaerator and withdrawn continuously as needed by the boiler feedwater pump.

Tray-Type Deaerator

Water flow is broken up by trickling down over a series of trays.
Entering steam scrubs the water in the lower trays and heats the water in the upper tray section.
Released gases and remaining steam pass to the internal vent condenser, where most of the steam is condensed and the gases are vented to atmosphere.

Combination Deaerator

Water is first sprayed into the upper heating section of the deaerator.
Then, it trickles over a series of steam-swept trays.
Released gases and remaining steam pass through the incoming water spray on their way to the vent opening, causing most of the steam to condense.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Learn about the importance of deaerators in boiler feedwater systems and how they prevent corrosion by removing dissolved gases from the water.