Please show system sketches and related energy flows for all problems. Solve the following:The utility providing the electricity to the boiler in problem 1.1 uses the same fuel as that used in problem 1.4 and has an efficiency of 0.35. The cost of the electric boiler is, $3,000 with a 15 year lifetime. The cost of the fuel based boiler system is $5000 and has a lifetime of 20 years. The fuel cost is $0.10/kg and the cost of electricity is $0.20/kWh. There is a tax charge of $0.50/kg of CO2 emission that is passed on to the user whether the utility based electrical system or gas fired system is used. The unit is used for 10 hours per day, 280 days per year. Which process would you recommend in terms of fuel consumption, exergy production, carbon dioxide emission and theroeconomic cost? There is no cost associated with the water input. Note the total amount of fuel consumed is directly related to the carbon dioxide emission from each process. Show below are the problems described in the above question:1.1 Determine the electrical power supplied to a boiler when the temperature of the entering water is 20 C and the exiting temperature is 89 C. The flow of.the pressured water is 2 Kg/s. There is a negligible pressure drop through this boiler and it operates at a constant pressure of 3 bars. The specific heat is c = 4,370 J/(Kg K). There is a 1.5(105 ) W rate of heat loss from the boiler during this process to a surrounding at 293.2 k. Consider steady state conditions.1.4 Calculate the mass flowrate of fuel (natural gas, CH4) required to heat the water flow to the conditions of problem 1.1 if the electrical heating device is replaced with a gas fired boiler. The high heating value (HHV) of the fuel is 50.02 MJ/kg.

Question
Asked Dec 6, 2019
246 views

Please show system sketches and related energy flows for all problems. Solve the following:

The utility providing the electricity to the boiler in problem 1.1 uses the same fuel as that used in problem 1.4 and has an efficiency of 0.35. The cost of the electric boiler is, $3,000 with a 15 year lifetime. The cost of the fuel based boiler system is $5000 and has a lifetime of 20 years. The fuel cost is $0.10/kg and the cost of electricity is $0.20/kWh. There is a tax charge of $0.50/kg of CO2 emission that is passed on to the user whether the utility based electrical system or gas fired system is used. The unit is used for 10 hours per day, 280 days per year. Which process would you recommend in terms of fuel consumption, exergy production, carbon dioxide emission and theroeconomic cost? There is no cost associated with the water input. Note the total amount of fuel consumed is directly related to the carbon dioxide emission from each process.

 

Show below are the problems described in the above question:

1.1 Determine the electrical power supplied to a boiler when the temperature of the entering water is 20 C and the exiting temperature is 89 C. The flow of.the pressured water is 2 Kg/s. There is a negligible pressure drop through this boiler and it operates at a constant pressure of 3 bars. The specific heat is c = 4,370 J/(Kg K). There is a 1.5(105 ) W rate of heat loss from the boiler during this process to a surrounding at 293.2 k. Consider steady state conditions.

1.4 Calculate the mass flowrate of fuel (natural gas, CH4) required to heat the water flow to the conditions of problem 1.1 if the electrical heating device is replaced with a gas fired boiler. The high heating value (HHV) of the fuel is 50.02 MJ/kg.

check_circle

Expert Answer

Step 1

Consider the following diagram for the boiler system, the heat input is ...

help_outline

Image Transcriptionclose

Pin t= 362K Ti=293K (2 oiler Inlet (-5(105) w Los

fullscreen

Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in

Engineering

Mechanical Engineering

Related Mechanical Engineering Q&A

Find answers to questions asked by student like you
Show more Q&A
add
question_answer

Q: To make 200 cast iron tool holders as shown in Figure 2 per order, two orders per year expected, and...

A: Consider the machining of harder material; this machining process induces high degree of stress and ...

question_answer

Q: A frictionless piston-cylinder device contains saturated liquid water at 40-psia pressure. Now 400 B...

A: The pressure of the saturated liquid water P1 = 40 psiaThe amount of heat transferred Q = 400 BtuThe...

question_answer

Q: For the system illustrated below, find the natural frequency.

A: Consider the free body diagram of the block, after displacing the x1 and x2 distance to the blocks.

question_answer

Q: I need the answer for problem number 8. I asked this questiona few days ago and received the answer ...

A: When the pilot valve (5) is vented, its spring returns and shifts the valve to its normal position. ...

question_answer

Q: An iron block of unknown mass at 185°F is dropped into an insulated tank that contains 0.8 ft of wat...

A: At first, determine the mass of water, mw, in which the iron block is dropped.

question_answer

Q: Three return steam lines in a chemical processing plant enter a collection tank operating at steady ...

A: Under steady state conditions of tank, the mass flow rate for the entire system should remain consta...

question_answer

Q: What is the tensile strength? Given: Material: aluminum Beam length: 9.75in Beam width:  .4155in Bea...

A: Given data as per question

question_answer

Q: 16. A roller-coaster car (Fig. P6.16) has a mass of 500 kg when fully loaded with passengers. The pa...

A: (a)Consider point A. The force due to gravity (weight) acts in the downward direction and normal for...

question_answer

Q: I need these 3 parts answered for a review activity.

A: (1)ASME standard is concerned with geometric irregularities of the surface. ASME standard includes r...