Podcast
Questions and Answers
EASY Why is propylene glycol used instead of ethylene glycol in certain situations?
EASY Why is propylene glycol used instead of ethylene glycol in certain situations?
- Because it is less toxic (correct)
- Because it is more viscous
- Because it has a longer life span
- Because it is cheaper
What is the primary reason for not mixing ethylene glycol and propylene glycol?
What is the primary reason for not mixing ethylene glycol and propylene glycol?
- They can cause inhibitors to precipitate (correct)
- They have different pH levels
- They have different specific heats
- They have different viscosities
What is the purpose of adding corrosion inhibitors to glycol heat transfer fluids?
What is the purpose of adding corrosion inhibitors to glycol heat transfer fluids?
- To react with oxygen to form organic acids
- To decrease the viscosity of the glycol
- To prevent corrosion caused by the reaction of glycol with oxygen (correct)
- To increase the pH of the system
Why is automotive glycol not recommended for industrial closed loop systems?
Why is automotive glycol not recommended for industrial closed loop systems?
What is the typical pH range of a glycol system with adequate inhibitor?
What is the typical pH range of a glycol system with adequate inhibitor?
What happens to the pH of a glycol system if the inhibitor is consumed?
What happens to the pH of a glycol system if the inhibitor is consumed?
Which glycol requires the most pumping power?
Which glycol requires the most pumping power?
Which glycol has the lowest specific heat?
Which glycol has the lowest specific heat?
What is the advantage of using propylene glycol over ethylene glycol?
What is the advantage of using propylene glycol over ethylene glycol?
What is the minimum glycol concentration recommended to avoid biological fouling?
What is the minimum glycol concentration recommended to avoid biological fouling?
What is the advantage of using glycol systems in remote sites?
What is the advantage of using glycol systems in remote sites?
What happens to the heat transfer capacity of a system when converted from water to glycol?
What happens to the heat transfer capacity of a system when converted from water to glycol?
Why should automatic municipal water make-up not be used in glycol systems?
Why should automatic municipal water make-up not be used in glycol systems?
What type of water should be mixed with glycol according to glycol manufacturers?
What type of water should be mixed with glycol according to glycol manufacturers?
What is the maximum level of chlorides permitted in dilution water for glycol systems?
What is the maximum level of chlorides permitted in dilution water for glycol systems?
Why should glycol not be used directly in a boiler or heater system?
Why should glycol not be used directly in a boiler or heater system?
MEDIUM What is the primary reason for the higher cost of glycol systems compared to water systems?
MEDIUM What is the primary reason for the higher cost of glycol systems compared to water systems?
What is the minimum recommended glycol concentration to prevent biological fouling?
What is the minimum recommended glycol concentration to prevent biological fouling?
Why are glycol systems a better option for remote sites?
Why are glycol systems a better option for remote sites?
What is the purpose of using a special tank and pump system for make-up in glycol systems?
What is the purpose of using a special tank and pump system for make-up in glycol systems?
What is the maximum level of sulfates permitted in dilution water for glycol systems?
What is the maximum level of sulfates permitted in dilution water for glycol systems?
Why is a heat exchanger necessary between the boiler and the closed loop system?
Why is a heat exchanger necessary between the boiler and the closed loop system?
What is the effect of using automatic municipal water make-up in glycol systems?
What is the effect of using automatic municipal water make-up in glycol systems?
What is the recommended range of glycol concentrations for temperatures between −15 to −20°C?
What is the recommended range of glycol concentrations for temperatures between −15 to −20°C?
What is the chemical formula of ethylene glycol?
What is the chemical formula of ethylene glycol?
Why do glycol heat transfer fluids require corrosion inhibitors?
Why do glycol heat transfer fluids require corrosion inhibitors?
What happens when ethylene glycol and propylene glycol are mixed together?
What happens when ethylene glycol and propylene glycol are mixed together?
What is the primary difference between propylene glycol and ethylene glycol in terms of freeze protection?
What is the primary difference between propylene glycol and ethylene glycol in terms of freeze protection?
Why is it important to monitor the pH of a glycol system?
Why is it important to monitor the pH of a glycol system?
What is a common problem that can occur in glycol systems if the pH drops below 7?
What is a common problem that can occur in glycol systems if the pH drops below 7?
What is the main reason why propylene glycol is more viscous than ethylene glycol?
What is the main reason why propylene glycol is more viscous than ethylene glycol?
What is a common service offered by glycol suppliers to help maintain the effectiveness of their products?
What is a common service offered by glycol suppliers to help maintain the effectiveness of their products?
HARD What is the primary reason why glycol systems require corrosion inhibitors?
HARD What is the primary reason why glycol systems require corrosion inhibitors?
What is the effect of mixing ethylene glycol and propylene glycol together?
What is the effect of mixing ethylene glycol and propylene glycol together?
Why is it important to monitor the pH of a glycol system?
Why is it important to monitor the pH of a glycol system?
What happens to the pH of a glycol system if the inhibitor is consumed?
What happens to the pH of a glycol system if the inhibitor is consumed?
Why is propylene glycol more viscous than ethylene glycol?
Why is propylene glycol more viscous than ethylene glycol?
What is a common problem that can occur in glycol systems if the pH drops below 7?
What is a common problem that can occur in glycol systems if the pH drops below 7?
What is a service offered by some glycol suppliers?
What is a service offered by some glycol suppliers?
What is the primary reason why glycol systems require less monitoring compared to water systems?
What is the primary reason why glycol systems require less monitoring compared to water systems?
What happens to the heat transfer capacity of a system when converted from water to glycol?
What happens to the heat transfer capacity of a system when converted from water to glycol?
Why is corrosion a concern in glycol systems?
Why is corrosion a concern in glycol systems?
What is the purpose of using a special tank and pump system for make-up in glycol systems?
What is the purpose of using a special tank and pump system for make-up in glycol systems?
What is the recommended minimum glycol concentration to prevent biological fouling?
What is the recommended minimum glycol concentration to prevent biological fouling?
What is the maximum level of total hardness permitted in dilution water for glycol systems?
What is the maximum level of total hardness permitted in dilution water for glycol systems?
Why should glycol not be used directly in a boiler or heater system?
Why should glycol not be used directly in a boiler or heater system?
What is the primary reason why propylene glycol is more expensive than ethylene glycol?
What is the primary reason why propylene glycol is more expensive than ethylene glycol?
What is the recommended concentration range of ethylene glycol for temperatures between −35 to −40°C?
What is the recommended concentration range of ethylene glycol for temperatures between −35 to −40°C?
Flashcards are hidden until you start studying
Study Notes
Glycol in Closed Systems
- Glycol is added to prevent freezing damage in closed system heating or cooling water.
- There are two main types of glycol: ethylene glycol [(CH2OH)2] and propylene glycol [C3H8O2].
- Ethylene glycol is toxic, while propylene glycol is not, making it suitable for use where food products are involved.
Characteristics of Glycols
- Glycols are more viscous than water, requiring more pumping power.
- Propylene glycol is the most viscous and requires a higher concentration to provide the same freeze protection as ethylene glycol.
- Both glycols have lower specific heats than water, with propylene having the lowest.
- Propylene glycol is more expensive than ethylene glycol.
Recommended Glycol Concentrations
- Table 3 shows the recommended glycol concentrations to achieve desired freeze protection:
- Temperature range −35 to −40 °C: 45-55% ethylene glycol, 50-54% propylene glycol
- Temperature range −15 to −20 °C: 30-35% ethylene glycol, 35-40% propylene glycol
- Glycol concentrations should never be less than 20% to prevent biological fouling.
Converting to Glycol Systems
- Glycol systems require less monitoring and are suitable for remote sites.
- Glycol solutions transfer less than half the heat of water, reducing heat transfer capacity by over 50%.
- Converting a water system to a glycol system increases costs and requires greater pumping power.
Maintenance and Inhibitors
- Glycol reacts with oxygen to form organic acids, increasing corrosion.
- Corrosion inhibitors are added to glycol heat transfer fluids.
- pH levels indicate the presence of adequate inhibitor, with a pH range of 9-9.5 being optimal.
- Test kits are available to check inhibitor levels.
Important Considerations
- Automotive glycol should not be used in industrial closed-loop systems.
- Ethylene glycol and propylene glycol should not be used together.
- Glycol should not be used directly in boiler or heater systems.
- A heat exchanger should be used between the boiler and the closed-loop system.
Glycol in Closed Systems
- Glycol is added to prevent freezing damage in closed system heating or cooling water.
- There are two main types of glycol: ethylene glycol [(CH2OH)2] and propylene glycol [C3H8O2].
- Ethylene glycol is toxic, while propylene glycol is not, making it suitable for use where food products are involved.
Characteristics of Glycols
- Glycols are more viscous than water, requiring more pumping power.
- Propylene glycol is the most viscous and requires a higher concentration to provide the same freeze protection as ethylene glycol.
- Both glycols have lower specific heats than water, with propylene having the lowest.
- Propylene glycol is more expensive than ethylene glycol.
Recommended Glycol Concentrations
- Table 3 shows the recommended glycol concentrations to achieve desired freeze protection:
- Temperature range −35 to −40 °C: 45-55% ethylene glycol, 50-54% propylene glycol
- Temperature range −15 to −20 °C: 30-35% ethylene glycol, 35-40% propylene glycol
- Glycol concentrations should never be less than 20% to prevent biological fouling.
Converting to Glycol Systems
- Glycol systems require less monitoring and are suitable for remote sites.
- Glycol solutions transfer less than half the heat of water, reducing heat transfer capacity by over 50%.
- Converting a water system to a glycol system increases costs and requires greater pumping power.
Maintenance and Inhibitors
- Glycol reacts with oxygen to form organic acids, increasing corrosion.
- Corrosion inhibitors are added to glycol heat transfer fluids.
- pH levels indicate the presence of adequate inhibitor, with a pH range of 9-9.5 being optimal.
- Test kits are available to check inhibitor levels.
Important Considerations
- Automotive glycol should not be used in industrial closed-loop systems.
- Ethylene glycol and propylene glycol should not be used together.
- Glycol should not be used directly in boiler or heater systems.
- A heat exchanger should be used between the boiler and the closed-loop system.
Glycol in Closed Systems
- Glycol is added to prevent freezing damage in closed system heating or cooling water.
- There are two main types of glycol: ethylene glycol [(CH2OH)2] and propylene glycol [C3H8O2].
- Ethylene glycol is toxic, while propylene glycol is not, making it suitable for use where food products are involved.
Characteristics of Glycols
- Glycols are more viscous than water, requiring more pumping power.
- Propylene glycol is the most viscous and requires a higher concentration to provide the same freeze protection as ethylene glycol.
- Both glycols have lower specific heats than water, with propylene having the lowest.
- Propylene glycol is more expensive than ethylene glycol.
Recommended Glycol Concentrations
- Table 3 shows the recommended glycol concentrations to achieve desired freeze protection:
- Temperature range −35 to −40 °C: 45-55% ethylene glycol, 50-54% propylene glycol
- Temperature range −15 to −20 °C: 30-35% ethylene glycol, 35-40% propylene glycol
- Glycol concentrations should never be less than 20% to prevent biological fouling.
Converting to Glycol Systems
- Glycol systems require less monitoring and are suitable for remote sites.
- Glycol solutions transfer less than half the heat of water, reducing heat transfer capacity by over 50%.
- Converting a water system to a glycol system increases costs and requires greater pumping power.
Maintenance and Inhibitors
- Glycol reacts with oxygen to form organic acids, increasing corrosion.
- Corrosion inhibitors are added to glycol heat transfer fluids.
- pH levels indicate the presence of adequate inhibitor, with a pH range of 9-9.5 being optimal.
- Test kits are available to check inhibitor levels.
Important Considerations
- Automotive glycol should not be used in industrial closed-loop systems.
- Ethylene glycol and propylene glycol should not be used together.
- Glycol should not be used directly in boiler or heater systems.
- A heat exchanger should be used between the boiler and the closed-loop system.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
