114 Questions
EASY What is one of the main reasons for boiler water treatment?
To prevent corrosion or pitting caused by high dissolved gases
What is a result of inefficient heat transfer in the boiler tubes?
Overheating and possible tube rupture
Which of the following is NOT a benefit of proper boiler water treatment?
Increased waste
What can happen if boiler drum water and suspended solids are carried over?
Tube failure or overheating
What is another term for the effect of sludge forming in boiler or steam drums and tubes?
Insulation
What can cause corrosion or pitting in boilers?
All of the above
Why is it important to install properly engineered water treatment equipment?
To save money on chemicals
What is the main goal of a water treatment program in a boiler system?
To protect the boiler investment
What is the typical problem that results from impurities in boiler water?
Sludge produced elsewhere but carried along by flowing water, will deposit on the boiler heat transfer surfaces.
What is the main goal of external treatment of boiler water?
To remove impurities from the raw water prior to entering the boiler.
What is the definition of suspended solids?
Substances that are held or suspended in the water.
What is the method of determining the concentration of suspended solids?
By running a given sample of the water through a standard 2 µm filter.
What is the typical method of reducing the levels of suspended solids?
Internal treatment using gravity settling and pressure filtration.
What is the definition of dissolved solids?
Ionic compounds dissolved in water.
What type of water has a higher concentration of suspended solids?
Surface water.
What is the purpose of boiler blowdown?
To remove suspended solids that have accumulated in the boiler.
What is the typical problem that results from dissolved solids in boiler water?
Formation of scales from salts.
What is the type of water that contains high dissolved salt concentrations, but less than the concentration of sea water?
Brackish water.
What is the primary cause of pitting in boilers?
Improperly treated feed water
What happens to the solubility of oxygen in water as the temperature rises?
It decreases towards zero
What is the purpose of a deaerator in boiler water treatment?
To raise the water temperature and remove dissolved oxygen
What is the effect of dissolved carbon dioxide in boiler water?
It forms carbonic acid, which can cause corrosion
What is the pH range of water from a municipal source?
6.75 to 8.0
What is the effect of high pH boiler water on the magnetite coating?
It dissolves the magnetite coating, causing caustic corrosion
What is the result of the reaction between CO2 and water in the boiler?
Formation of carbonic acid
What is the safe range of pH for boiler water?
8.5 to 12.7
What is the result of the decomposition of calcium bicarbonate at high temperatures?
Liberation of CO2
What is the effect of acidic water on boiler corrosion?
It increases corrosion
What do calcium and magnesium salts appear as when conducting hardness tests?
Dissolved solids
What is the equivalent unit of measurement for PPM in liquids?
mg/L
What is the primary problem caused by hardness in boiler water?
Boiler tube scaling
What type of hardness is caused by the bicarbonates of calcium and magnesium?
Temporary hardness
What is the primary method for removing silica ions from water?
Lime softening
What is the result of sludge and scale buildup in a boiler?
Decreased heat transfer
What is the primary cause of foaming in a boiler?
Oils or suspended solids
What is the purpose of blowing down the boiler mud drum?
To remove sludge
What is the primary concern of dissolved gases in boiler water?
Boiler corrosion
What is the typical method for removing dissolved solids from water?
All of the above
MEDIUM What is the primary consequence of inefficient heat transfer in a boiler system?
Tube rupture
What is the primary purpose of a water treatment program in a boiler system?
To protect a facility's boiler investment
What is the effect of high concentrations of dissolved or suspended solids on boiler operation?
Inefficient heat transfer and tube insulation
What is the primary consequence of carryover of boiler drum water and suspended solids?
Overheating of tube surfaces or tube failure
What is the primary benefit of installing properly engineered water treatment equipment?
Considerable savings on maintenance and labour
What is the primary source of impurities in boiler water?
All of the above
What is the primary consequence of corrosion or pitting in boilers?
Tube rupture
What is the primary objective of a water treatment program in a boiler system?
To ensure the required level of steam purity
What is the primary problem caused by hardness in boiler water?
Boiler tube scaling
What is the equivalent unit of measurement for PPM in liquids?
Mg/L
What type of hardness is caused by the bicarbonates of calcium and magnesium?
Temporary hardness
What is the primary method for removing silica ions from water?
Reverse osmosis
What is the result of sludge and scale buildup in a boiler?
Reduced boiler efficiency
What is the primary cause of foaming in a boiler?
Oils or suspended solids
What is the purpose of blowing down the boiler mud drum?
To remove sludge
What is the primary concern of dissolved gases in boiler water?
Corrosion
How do calcium and magnesium salts appear when conducting hardness tests?
As dissolved solids
What is the common method for removing dissolved solids from water?
All of the above
What is the primary cause of pitting corrosion in boilers?
Dissolved oxygen in the feed water
What is the purpose of a deaerator in boiler water treatment?
To remove dissolved oxygen from the feed water
What is the effect of high pH boiler water on the magnetite coating?
It dissolves the magnetite coating
What is the safe range of pH for boiler water?
8.5 to 12.7
What is the result of the reaction between CO2 and water in the boiler?
Formation of carbonic acid
What is the effect of acidic water on boiler corrosion?
It increases the rate of corrosion
What is the result of the decomposition of calcium bicarbonate at high temperatures?
Liberation of CO2
What is the purpose of removing dissolved oxygen from the feed water?
To reduce the risk of corrosion
What is the effect of dissolved carbon dioxide in boiler water?
It decreases the pH of the boiler water
What is the typical pH range of water from a municipal source?
6.75
What is the primary reason why impurities in boiler water need to be removed?
To prevent corrosion and catastrophic failure
What type of impurities are carried along suspended in the flow of water?
Suspended solids
What is the result of scale formation from salts in boiler water?
Reduced efficiency of the boiler
What is the purpose of internal treatment of boiler water?
To add chemicals that target problematic impurities
What is the typical method of measuring the concentration of suspended solids?
By running a sample of the water through a standard 2 µm filter
What is the effect of suspended solids on the boiler heat transfer surfaces?
It reduces the heat transfer rate
What is the primary method of removing dissolved solids from water?
Ion exchange
What is the result of carryover from impurities in boiler water?
Negatively affected purity of the steam
What type of water is more likely to have higher concentrations of suspended solids?
Surface water
What is the purpose of boiler blowdown?
To remove suspended solids that have accumulated in the boiler
HARD What is the primary consequence of inefficient heat transfer in a boiler system due to impurities?
All of the above
What is the primary benefit of external treatment of boiler water?
Removal of suspended solids and dissolved gases
What is the primary concern with dissolved gases in boiler water?
Corrosion and pitting
What is the primary method for reducing the levels of suspended solids in boiler water?
Gravity settling and pressure filtration
What is the primary problem caused by hardness in boiler water?
Scale formation and corrosion
What is the primary purpose of internal treatment of boiler water?
Addition of chemicals to target problematic impurities
What is the primary consequence of carryover of boiler drum water and suspended solids?
Contamination of superheaters and turbines
What is the primary cause of pitting corrosion in boilers?
Oxygen carried over with the steam
What is the effect of dissolved oxygen on boiler water?
It causes pitting corrosion in the boiler metal
What is the primary reason for removing dissolved solids from boiler water?
To prevent boiler tube scaling and increase heat transfer efficiency
What is the primary method for removing dissolved solids from water?
Reverse osmosis and deionization
What is the most common method used to remove silica ions from water?
Lime softening
What is the purpose of a deaerator in boiler water treatment?
To remove oxygen and carbon dioxide from the feed water
What is the primary cause of corrosion or pitting in boilers?
Dissolved oxygen and carbon dioxide
What is the primary benefit of proper boiler water treatment?
All of the above
What is the effect of acidic water on boiler corrosion?
It increases the corrosion rate of the boiler metal
What is the primary consequence of sludge and scale buildup in a boiler?
Decreased boiler efficiency and increased risk of overheating
What is the primary concern of dissolved gases in boiler water?
Production of ferrous metal corrosion
What is the safe range of pH for boiler water?
8.5 to 12.7
What is the primary method used to remove dissolved solids from water?
All of the above
What is the effect of high pH boiler water on the magnetite coating?
It dissolves the magnetite coating
What is the result of the reaction between CO2 and water in the boiler?
Formation of carbonic acid
What is the primary benefit of properly engineered water treatment equipment?
Improved boiler water quality and reduced maintenance
What is the primary purpose of boiler blowdown?
To remove sludge from the boiler mud drum
What is the effect of dissolved carbon dioxide in boiler water?
It forms carbonic acid in the condensate lines
What is the primary consequence of carryover of boiler drum water and suspended solids?
Contamination of the steam and potential damage to turbines
What is the primary cause of corrosion in copper and copper-bearing alloys?
Ammonia in the boiler water
What is the purpose of adding neutralizing agents to the boiler water?
To inhibit carbonic acid formation in the condensate lines
What is the primary problem caused by hardness in boiler water?
Boiler tube scaling and reduced heat transfer efficiency
What is the equivalent unit of measurement for PPM in liquids?
Mg/L
What is the primary consequence of inefficient heat transfer in a boiler system due to scale formation?
Overheating of tube surfaces or even tube failure
What is the primary benefit of removing dissolved gases from boiler water?
Reducing the risk of corrosion or pitting
What is the primary consequence of carryover of boiler drum water and suspended solids?
Inefficient heat transfer and possible tube failure
What is the primary purpose of a water treatment program in a boiler system?
To protect the boiler investment and ensure efficient operation
What is the primary consequence of corrosion or pitting in boilers?
Inefficient heat transfer and possible tube failure
What is the primary source of impurities in boiler water?
From the water source itself
What is the primary benefit of installing properly engineered water treatment equipment?
Savings on maintenance and labor costs
What is the primary consequence of sludge forming in boiler or steam drums and tubes?
Inefficient heat transfer and possible tube failure
Study Notes
Importance of Boiler Water Treatment
- Prevents scale formation on boiler tubes, which can cause inefficient heat transfer, overheating, and tube rupture
- Prevents sludge formation in boiler and steam drums, which can cause inefficient heat transfer, overheating, and tube failure
- Prevents corrosion and pitting caused by high dissolved gases, concentrations of dissolved or suspended solids, and high or low pH levels
- Prevents carryover of boiler drum water and dissolved or suspended solids, which can affect steam purity
- Ensures required level of steam purity, which is critical for efficient equipment operation, increased boiler life expectancy, reduced fuel use, optimized water use, reduced waste, and considerable savings on maintenance and labor
Impurities in Boiler Water
- Suspended solids: small particles that are insoluble in water, such as clay, sand, silica, and organic material
- Can form deposits on boiler heat transfer surfaces, reducing heat exchange and leading to metal failure or under deposit corrosion
- Can cause foaming, which results in carryover or priming from the steam drum
- Dissolved solids: ionic compounds dissolved in water, such as calcium and magnesium salts
- Can react chemically with other ions and precipitate on heating surfaces, causing local hot spots and tube rupture
- Can cause hardness in boiler water, leading to scaling and reduced heat transfer efficiency
- Dissolved gases: gases that are in solution, such as oxygen, ammonia, and carbon dioxide
- Can cause corrosion, pitting, and damage to boiler surfaces and condensate return lines
- Can affect steam purity and lead to corrosion in copper and copper-bearing alloys
Types of Impurities and Their Effects
- Calcium salts:
- Can cause scaling and reduced heat transfer efficiency
- Can cause local hot spots and tube rupture
- Magnesium salts:
- Can cause scaling and reduced heat transfer efficiency
- Can cause local hot spots and tube rupture
- Silica:
- Can form colloidal silica, which can cause foaming and carryover
- Can be removed using lime softening, reverse osmosis, and ion exchange
- Oxygen:
- Can cause pitting and corrosion in ferrous metals
- Can be removed using deaerators and internal treatment methods
- Carbon dioxide:
- Can cause corrosion in copper and copper-bearing alloys
- Can form carbonic acid, which can cause grooving on metal surfaces
pH and Acidic Conditions
- Measured on the pH scale, with a neutral pH of 7
- Acidic conditions can cause corrosion in boiler steels
- pH range of 8.5 to 12.7 is considered "safe" for boiler operation
- Outside this range, corrosion can be significant
- High pH boiler water can dissolve magnetite coating, causing caustic corrosion and boiler metal failure
Importance of Boiler Water Treatment
- Prevents scale formation on boiler tubes, which can cause inefficient heat transfer, overheating, and tube rupture
- Prevents sludge formation in boiler and steam drums, which can cause inefficient heat transfer, overheating, and tube failure
- Prevents corrosion and pitting caused by high dissolved gases, concentrations of dissolved or suspended solids, and high or low pH levels
- Prevents carryover of boiler drum water and dissolved or suspended solids, which can affect steam purity
- Ensures required level of steam purity, which is critical for efficient equipment operation, increased boiler life expectancy, reduced fuel use, optimized water use, reduced waste, and considerable savings on maintenance and labor
Impurities in Boiler Water
- Suspended solids: small particles that are insoluble in water, such as clay, sand, silica, and organic material
- Can form deposits on boiler heat transfer surfaces, reducing heat exchange and leading to metal failure or under deposit corrosion
- Can cause foaming, which results in carryover or priming from the steam drum
- Dissolved solids: ionic compounds dissolved in water, such as calcium and magnesium salts
- Can react chemically with other ions and precipitate on heating surfaces, causing local hot spots and tube rupture
- Can cause hardness in boiler water, leading to scaling and reduced heat transfer efficiency
- Dissolved gases: gases that are in solution, such as oxygen, ammonia, and carbon dioxide
- Can cause corrosion, pitting, and damage to boiler surfaces and condensate return lines
- Can affect steam purity and lead to corrosion in copper and copper-bearing alloys
Types of Impurities and Their Effects
- Calcium salts:
- Can cause scaling and reduced heat transfer efficiency
- Can cause local hot spots and tube rupture
- Magnesium salts:
- Can cause scaling and reduced heat transfer efficiency
- Can cause local hot spots and tube rupture
- Silica:
- Can form colloidal silica, which can cause foaming and carryover
- Can be removed using lime softening, reverse osmosis, and ion exchange
- Oxygen:
- Can cause pitting and corrosion in ferrous metals
- Can be removed using deaerators and internal treatment methods
- Carbon dioxide:
- Can cause corrosion in copper and copper-bearing alloys
- Can form carbonic acid, which can cause grooving on metal surfaces
pH and Acidic Conditions
- Measured on the pH scale, with a neutral pH of 7
- Acidic conditions can cause corrosion in boiler steels
- pH range of 8.5 to 12.7 is considered "safe" for boiler operation
- Outside this range, corrosion can be significant
- High pH boiler water can dissolve magnetite coating, causing caustic corrosion and boiler metal failure
Importance of Boiler Water Treatment
- Prevents scale formation on boiler tubes, which can cause inefficient heat transfer, overheating, and tube rupture
- Prevents sludge formation in boiler and steam drums, which can cause inefficient heat transfer, overheating, and tube failure
- Prevents corrosion and pitting caused by high dissolved gases, concentrations of dissolved or suspended solids, and high or low pH levels
- Prevents carryover of boiler drum water and dissolved or suspended solids, which can affect steam purity
- Ensures required level of steam purity, which is critical for efficient equipment operation, increased boiler life expectancy, reduced fuel use, optimized water use, reduced waste, and considerable savings on maintenance and labor
Impurities in Boiler Water
- Suspended solids: small particles that are insoluble in water, such as clay, sand, silica, and organic material
- Can form deposits on boiler heat transfer surfaces, reducing heat exchange and leading to metal failure or under deposit corrosion
- Can cause foaming, which results in carryover or priming from the steam drum
- Dissolved solids: ionic compounds dissolved in water, such as calcium and magnesium salts
- Can react chemically with other ions and precipitate on heating surfaces, causing local hot spots and tube rupture
- Can cause hardness in boiler water, leading to scaling and reduced heat transfer efficiency
- Dissolved gases: gases that are in solution, such as oxygen, ammonia, and carbon dioxide
- Can cause corrosion, pitting, and damage to boiler surfaces and condensate return lines
- Can affect steam purity and lead to corrosion in copper and copper-bearing alloys
Types of Impurities and Their Effects
- Calcium salts:
- Can cause scaling and reduced heat transfer efficiency
- Can cause local hot spots and tube rupture
- Magnesium salts:
- Can cause scaling and reduced heat transfer efficiency
- Can cause local hot spots and tube rupture
- Silica:
- Can form colloidal silica, which can cause foaming and carryover
- Can be removed using lime softening, reverse osmosis, and ion exchange
- Oxygen:
- Can cause pitting and corrosion in ferrous metals
- Can be removed using deaerators and internal treatment methods
- Carbon dioxide:
- Can cause corrosion in copper and copper-bearing alloys
- Can form carbonic acid, which can cause grooving on metal surfaces
pH and Acidic Conditions
- Measured on the pH scale, with a neutral pH of 7
- Acidic conditions can cause corrosion in boiler steels
- pH range of 8.5 to 12.7 is considered "safe" for boiler operation
- Outside this range, corrosion can be significant
- High pH boiler water can dissolve magnetite coating, causing caustic corrosion and boiler metal failure
This quiz covers the reasons why boiler water treatment is necessary, including preventing scale and sludge formation, and corrosion. Learn about the importance of efficient heat transfer and preventing overheating.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
