A steam trap is a device to purge steam condensate from a system without venting uncondensed...
Fantastic news! We've Found the answer you've been seeking!
Question:
Transcribed Image Text:
A steam trap is a device to purge steam condensate from a system without venting uncondensed steam. In one of the crudest trap types, the condensate collects and raises a float attached to a drain plug. When the float reaches a certain level, it "pulls the plug," opening the drain valve and allowing the liquid to discharge. The float then drops down to its original position and the valve closes, preventing uncondensed steam from escaping. a) Suppose saturated steam at 25 bar is used to heat 100 kg/min of an oil from 135°C to 185°C. Heat must be transferred to the oil at a rate of 1.00 \times 10^(4} \mathrm{kJ} / Imathrm{min} to accomplish this task. The steam condenses on the exterior of a bundle of tubes through which the oil is flowing. Condensate collects in the bottom of the exchanger and exits through a steam trap set to discharge when 1200 g of liquid is collected. How often does the trap discharge? b) Especially when periodic maintenance checks are not performed, steam traps often fail to close completely and so leak steam continuously. Suppose a process plant contains 1000 leaking traps (not an unrealistic supposition for some plants) operating at the condition of Part (a), and that on the average 10% additional steam must be fed to the condensers to compensate for the uncondensed steam venting through the leaks. Further suppose that the cost of generating the additional steam is $7.50 per million Btu, where the denominator refers to the enthalpy of the leaking steam relative to liquid water at 20°C. Estimate the yearly cost of the leaks based on 24 h/day, 360 day/yr operation. A steam trap is a device to purge steam condensate from a system without venting uncondensed steam. In one of the crudest trap types, the condensate collects and raises a float attached to a drain plug. When the float reaches a certain level, it "pulls the plug," opening the drain valve and allowing the liquid to discharge. The float then drops down to its original position and the valve closes, preventing uncondensed steam from escaping. a) Suppose saturated steam at 25 bar is used to heat 100 kg/min of an oil from 135°C to 185°C. Heat must be transferred to the oil at a rate of 1.00 \times 10^(4} \mathrm{kJ} / Imathrm{min} to accomplish this task. The steam condenses on the exterior of a bundle of tubes through which the oil is flowing. Condensate collects in the bottom of the exchanger and exits through a steam trap set to discharge when 1200 g of liquid is collected. How often does the trap discharge? b) Especially when periodic maintenance checks are not performed, steam traps often fail to close completely and so leak steam continuously. Suppose a process plant contains 1000 leaking traps (not an unrealistic supposition for some plants) operating at the condition of Part (a), and that on the average 10% additional steam must be fed to the condensers to compensate for the uncondensed steam venting through the leaks. Further suppose that the cost of generating the additional steam is $7.50 per million Btu, where the denominator refers to the enthalpy of the leaking steam relative to liquid water at 20°C. Estimate the yearly cost of the leaks based on 24 h/day, 360 day/yr operation.
Expert Answer:
Answer rating: 100% (QA)
From the passage provided amount of heat transfer 10000 KJmin Data for steam Pressure 5 bar It is gi... View the full answer
Related Book For
Principles of heat transfer
ISBN: 978-0495667704
7th Edition
Authors: Frank Kreith, Raj M. Manglik, Mark S. Bohn
Posted Date:
Students also viewed these chemical engineering questions
-
A double-pipe parallel-flow heat exchanger is used to heat cold tap water with hot water. Hot water (c p = 4.25 kJ/kg·K) enters the tube at 85°C at a rate of 1.4 kg/s and leaves at...
-
An adiabatic heat exchanger is used to heat cold water at 15C entering at a rate of 5 kg/s by hot water at 90C entering at a rate of 4 kg/s. If the exit temperature of hot water is 50C, the exit...
-
A 1-shell-pass and 8-tube-passes heat exchanger is used to heat glycerin (cp = 0.60 Btu/lbm(oF) from 65oF to 140oF by hot water (cp = 1.0 Btu/ lbm(oF) that enters the thin-walled 0.5-in-diameter...
-
For each of the following demand functions, check whether they satisfy the weak axiom of revealed preferences (WARP) (a) "Random Demand". For any pair of prices p and p2 and income m, the consumer...
-
The markup on greeting cards in a drug store is 65% of the selling price. For a card priced at $4.95, determine: a. Its cost. b. The rate of markup on cost.
-
Find the equivalent resistance of the circuit shown at the terminals A-B. 12 kQ 12 kQ 6 kQ 6 kQ RAB 12 kQ 12 kQ 4 kQ
-
Looking at the days (rows) as blocks, rework Exercise 12.5 by the method of Section 12.3. Data From Exercise 12.5 12.5 The following are the numbers of mistakes made in 5 successive days for 4...
-
Westinghouse Electric Corporation entered into uranium supply contracts with 22 electric utilities during the late 1960s. The contract prices ranged from $7 to $10 per pound. The Arab oil embargo and...
-
What is the importance of a comprehensive root cause analysis (RCA) following a safety incident or near-miss? How do RCA techniques contribute to continuous improvement and the prevention of future...
-
In Part III (Appendix 11B) of the audit case, the audit staff of Adams, Barnes & Co. identified specific revenue risks on working paper RA-12 (page 494). However, the Summary of Audit Approach...
-
Grant wants to make meatballs for pasta supper. He needs to defrost 1.56 kg of ground beef .It takes 12 minutes to defrost 2 Lbs of meat, How long will it take for gran's1.56 kg of ground beef to...
-
How do you evaluate the leadership of Wolfgang Keller based on an understanding of leadership? Write a review report for Keller's boss assessing his leadership, what would you say? Write as a draft...
-
The figure shows a uniform electric field E. The distances between pairs of points are: dKM 0.12m, dux -0.09m, dLM -0.15m, The electric potential difference |AV| between points K and M is measured to...
-
What is an embedded operating system? What are two examples of popular embedded operating systems that are used in everyday objects?
-
how do you get direct manufacturing labor for budgeted input for actual output?
-
7. x+1 = 2x-3, find x.
-
Mandated nurse-to-patient ratios affect potentially all hospitals and spark much debate in terms of their merits and feasibility of enforcement. The ratio itself is not precise and is influenced by...
-
What is a manufacturing system?
-
Ball bearings are to be hardened by quenching them in a water bath at a temperature of 37?C. Suppose you are asked to devise a continuous process in which the balls could roll from a soaking oven at...
-
Calculate the rate of heat transfer between a pain of concentric horizontal cylinders 20 mm and 126 mm in diameter. The inner cylinder is maintained at 37C and the outer cylinder is maintained at...
-
Estimate (a) The heat transfer coefficient for a spherical fuel droplet injected into a diesel engine at 80C and 90 m/s. The oil droplet is 0.025 mm in diameter, the cylinder pressure is 4800 kPa,...
-
If task A is an immediate predecessor of task B, what must be true about the sched- uled timing of these two tasks?
-
Why does a project necessarily have to possess some form of deadline? What is the implication of a project without a deadline?
-
What are the likely consequences to managing a highly uncertain project in the predictive style of project management?
Study smarter with the SolutionInn App