Explanation of Boiler Feed Water & Its Treatment | Engineering Chemistry

Summary

Boiler feed water is essential for generating steam in industrial boilers, which is used for power and heating. Natural water sources are unfit due to impurities, necessitating pre-treatment to remove contaminants. This treated water, combined with returned condensate and makeup water, forms the boiler feed. Proper treatment is crucial to prevent scale formation, corrosion, and ensure efficient heat transfer. Key specifications include hardness below 2 ppm, alkalinity levels, and freedom from turbidity, sediments, organic matter, oil, and grease.

Takeaways

• 🔥 Boilers are essential in industries for generating steam, which is used for power and heat production.
• 🔨 The boiler consists of two main components: the furnace, which provides heat by burning fuel, and the boiler proper, where water turns into steam.
• 💧 Modern boilers require high-quality water for efficient operation, which is not readily available from natural sources due to impurities.
• 🌀 Boiler feed water is specially conditioned water that is fed into the boiler to produce steam or hot water.
• 🔄 Steam is condensed after use and returned as pure feed water, mixed with fresh water or makeup water to form boiler feed water.
• 🚰 The quality of boiler feed water depends on the makeup water and the amount of condensate returned to the boiler.
• 🧹 Impurities can accumulate at the bottom of the boiler, which can be removed by the blowdown operation, discharging water to the drain.
• 🛡️ Proper treatment of boiler feed water is crucial to prevent the concentration of dissolved solids that can cause poor heat transfer and boiler corrosion.
• 📋 Boiler feed water should meet specific specifications, including hardness below 2 ppm, and alkalinity within certain ppm ranges.
• 🌿 The water must be free from turbidity, sediments, organic matter, oil, and grease to avoid fouling.
• 🚰 In thermal power stations, feed water is stored, preheated, and conditioned before being pumped into the boiler.

Q & A

What is the primary purpose of a boiler in an industrial setting?

The primary purpose of a boiler in an industrial setting is to generate steam, which is then used to generate power and heat.

What are the two main components of a boiler?

The two main components of a boiler are the furnace, which provides heat by burning fuel, and the boiler proper, where water is converted into steam due to heat.

Why is boiler feed water important for the efficient operation of modern boilers?

Boiler feed water is important because modern boilers require high-quality water to operate efficiently, and natural sources of water contain impurities that make them unfit for use in boilers.

What is the process of treating water to make it suitable for use in boilers called?

The process of treating water to make it suitable for use in boilers is called pre-treatment, which involves various techniques to remove impurities.

What is the difference between boiler feed water and return water?

Boiler feed water is the specially conditioned water fed into the boiler to generate steam or hot water, while return water is the steam that has been condensed after use and is returned as pure feed water.

What is the purpose of blowdown operation in a boiler system?

The purpose of blowdown operation is to remove impurities that have settled at the bottom of the boiler by discharging some water to the drain.

Why is it necessary to treat boiler feed water properly?

Proper treatment of boiler feed water is necessary to prevent the concentration of dissolved solids that can form deposits, leading to poor heat transfer and reduced boiler efficiency, as well as to protect the boiler from corrosion caused by dissolved gases like oxygen and carbon dioxide.

What are the typical specifications for boiler feed water hardness and alkalinity?

The hardness of boiler feed water should be below 2 parts per million, and its total alkalinity should be between 15 and 45 parts per million, while soda alkalinity should be between 45 and 1 part per million.

What should boiler feed water be free from to avoid forming deposits?

Boiler feed water should be free from turbidity, sediments, organic matter, oil, and grease to avoid forming deposits.

How is feed water typically stored and conditioned before being fed into the boiler in thermal power stations?

In thermal power stations, feed water is usually stored, preheated, and conditioned in the feed water tank before being forwarded into the boiler through the boiler feed water pump.

Outlines

00:00

🔥 Boiler Feed Water and Its Importance

This paragraph explains the concept of boiler feed water and its significance in industrial processes. Boilers are used to generate steam for power and heating, consisting of a furnace for heat production and a boiler where water turns into steam. Modern boilers demand high-quality water, which is pre-treated to remove impurities found in natural sources. The treated water, known as boiler feed water, is a blend of return water from steam condensation and fresh makeup water. The paragraph also touches on the issue of impurities settling in the boiler, which are managed through a blowdown operation. The importance of proper water treatment is emphasized to prevent heat transfer inefficiencies and corrosion due to dissolved solids and gases.

Keywords

💡Boiler

A boiler is a closed vessel in which water or other fluid is heated to generate steam. In the context of the video, boilers are essential in industries for generating steam that is then used to produce power and heat. The script mentions that a boiler consists of two main parts: the furnace, which provides heat by burning fuel, and the boiler proper, where water is converted into steam.

💡Boiler Feed Water

Boiler feed water refers to the water that is fed into the boiler to generate steam or hot water. The script emphasizes that modern boilers require high-quality water to operate efficiently, which is why the feed water must be pre-treated to remove impurities. The quality of boiler feed water is crucial for the boiler's efficiency and longevity.

💡Furnace

The furnace is the part of the boiler system that provides heat by burning fuel. It is mentioned in the script as the component responsible for supplying the necessary heat to the boiler proper, where the water is turned into steam. The furnace's efficiency directly impacts the boiler's overall performance.

💡Steam

Steam is the gaseous phase of water that is produced when water is heated in a boiler. The script explains that steam is used in various industrial processes for power generation and heating applications. The production of steam is the primary function of a boiler, making it a central concept in the video's theme.

💡Impurities

Impurities are substances that are not wanted in the boiler feed water because they can cause problems such as scale formation and corrosion. The script states that natural water sources contain impurities that make the water unfit for use in boilers, necessitating pre-treatment to ensure the water is suitable for steam generation.

💡Pre-treatment

Pre-treatment is the process of treating water to remove impurities before it is used as boiler feed water. The script mentions that pre-treatment is necessary to ensure the water is of high quality and suitable for use in boilers, highlighting the importance of this process in maintaining boiler efficiency.

💡Return Water

Return water is the steam that has been condensed after use and is returned to the boiler system as pure feed water. The script explains that return water is combined with fresh water or makeup water to form the boiler feed water, emphasizing the role of return water in the boiler's water cycle.

💡Makeup Water

Makeup water is the fresh water that is added to the return water to compensate for the water that has been evaporated during the steam generation process. The script mentions that the combination of return water and makeup water is what constitutes the boiler feed water, illustrating the continuous need for replenishing the boiler's water supply.

💡Blowdown

Blowdown is the process of discharging some water from the boiler to the drain to remove impurities that have settled at the bottom of the boiler. The script describes blowdown as a method to prevent the accumulation of impurities, which can otherwise lead to poor heat transfer and reduced boiler efficiency.

💡Hardness

Hardness refers to the concentration of dissolved calcium and magnesium ions in water. The script specifies that boiler feed water should have a hardness below 2 parts per million, indicating that low hardness is a critical specification for preventing scale formation and maintaining boiler efficiency.

💡Alkalinity

Alkalinity is the measure of a water's ability to neutralize acids and is an important parameter for boiler feed water. The script mentions two types of alkalinity: carbonate (between .15 and 45 parts per million) and soda (between 45 and 1 part per million), which are crucial for maintaining the correct chemical balance in the boiler system.

💡Turbidity

Turbidity is the cloudiness or haziness in a fluid caused by individual particles that are generally invisible to the naked eye. The script states that boiler feed water should be free from turbidity and sediments, which is essential for preventing the buildup of particles that can interfere with the boiler's operation.

💡Organic Matter

Organic matter refers to any substance that contains carbon and is derived from living organisms. The script emphasizes that boiler feed water should be free from organic matter, oil, and grease to avoid forming deposits that can foul the boiler and reduce its efficiency.

Highlights

Boilers are used in industries to generate steam for power and heat production.

Boilers consist of a furnace for heat and a boiler for water-to-steam conversion.

Modern boilers require high-quality water for efficient operation.

Natural water sources contain impurities making them unsuitable for boilers.

Boiler feed water is pre-treated to remove impurities for use in boilers.

Steam produced in boilers is condensed and returned as pure feed water.

Return water combined with makeup water forms the boiler feed water.

Impurities can accumulate at the bottom of the boiler and are removed through blowdown operations.

Proper treatment of boiler feed water is crucial for efficient boiler operation and maintenance.

Concentrated dissolved solids from steam production can lead to boiler deposits and poor heat transfer.

Dissolved gases like oxygen and carbon dioxide can cause corrosion in boiler systems.

Boiler feed water should be treated to protect against contaminants.

Hardness of boiler feed water should be below 2 parts per million.

Custic alkalinity should be maintained between .15 and 45 parts per million.

Soda alkalinity should be between 45 and 1 parts per million.

Boiler feed water must be free from turbidity, sediments, organic matter, oil, and grease.

In thermal power stations, feed water is stored, preheated, and conditioned before being fed into the boiler.

Transcripts

explain boiler feed water and give its

specifications generally boilers are

used in Industries to generate steam

which in turn is used to generate power

and heat thus boiler is a device for

generating

steam it consists of two main parts

furnace and boiler

proper furnace provides Heat by burning

the

fuel and boiler proper is a device where

water changes into steam due to

heat this steam or hot fluid is then

recirculated out of the boiler to be

used in various processes in heating

applications the water which is fed into

the boiler is called the boiler feed

water these days modern boilers require

high quality water to operate

efficiently but such water can never be

obtained from any of the natural sources

as it contains certain

impurities the presence of impurities in

the water makes it unfit for use in the

boilers so to make the water fit for use

in boilers it should be pre-treated

using various

techniques thus we can say that boiler

feed water is specially conditioned

water which is fed into the boiler to

generate steam or hot

water it is generated through a system

of heat

economy steam produced in the

boiler is condensed after

use and is returned as pure feed water

called the return

water then some fresh water or makeup

water is added to this return

water it is this combination of return

turn

water and make up

water which is fed into the

boiler as the boiler feed water to

generate steam note that boiler feed

water depends upon the quality of the

makeup water and the amount of

condensate returned to the

boiler sometimes we see that some

impurities settle down at the bottom of

the boiler after the steam is produced

we know that steam which escapes from

the boiler normally contains liquid

droplets and gases so the remaining

water at the bottom of the boiler might

pick up all the foreign matter from the

water that was converted to steam this

results in the accumulation of

impurities at the bottom of the boiler

these impurities can be removed by

discharging some water from the boiler

to the

drain such process of blowing the

impurities from the boiler to the drain

is called blowdown

operation in order to operate and

maintain a boiler system efficiently it

is important to treat the boiler feed

water properly this is because when

steam is produced the dissolved solids

become concentrated and form deposits

inside the

boiler this leads to poor heat transfer

and reduces the efficiency of the

boiler also the dissolved gas such as

oxygen and carbon dioxide react react

with the metals in the boiler system and

this leads to boiler

corrosion thus to protect the boiler

from such contaminants the boiler feed

water should be treated properly through

external or internal

treatment let us now discuss the

specifications of boiler feed water

before using the boiler feed water in

the boiler it should be made sure that

it meets the following specifications

its hardness should be below 2 parts per

million its costic alkalinity should be

between .15 and 45 parts per million its

soda alkalinity should be between 45 and

1 parts per million it should be free

from turbidity and

sediments and it should be free from

organic matter oil and grease to avoid

forming note that in thermal power

stations feed water is usually stored

preheated and conditioned in the feed

water tank and then forward it into the

boiler through the boiler feed water

pump related terms

are