Casework 4
Boilers & Steam Distribution Systems
Assignment due: See email from instructor & CANVAS website.
Case Description
A facility is operating for 16 hours/day and 5 days per week, throughout the year. The plant is served by a natural gas supplier. Process steam is required at 300 deg F. The steam generated by a natural gas-fired boiler is for process use only and is being used in six identical steam ovens. The boiler is a fire-tube natural-draft boiler of 60 hp and runs 24×7. The facility conducted an evaluation of the boiler performance and found that the fire tube boiler had a stack temperature of 500 deg F with flue gas containing 9% oxygen. The steam is generated from the boiler at 30 psia. The load factor throughout the year is 80%. Recently due to less production, two steam ovens are not in use but are not isolated properly. The condensate from the machines is sent to the drain at a temperature of 150 deg F. The dew point of flue gas is 160 deg F. The desired temperature of feed water is 180 deg F. The inspection of the system showed that 5 steam traps were faulty and were each venting steam through a 1/8 inch “hole”. Water is supplied by the city waterworks authority at a temperature of 65 deg F. The boiler maintenance company recommended the facility to check the water quality—and the uncontrolled continuous blowdown of water that is done to maintain water quality in the boiler.
Questions
- List all the possible energy-saving opportunities for the above scenario. Write a “Recommended Action” for each opportunity. Just write the verbal recommendation, not the savings Not more than 200 words each. (30 points)
- Calculate the energy savings for any three of these and clearly state the assumptions in your calculations. In other words, do three energy-saving calculations. NOTE: Just calculate the energy and cost savings for one year. List your assumed reasonable fuel cost per Do not calculate the project cost and simple payback. (70 points)
Note
Assume reasonable data. Clearly mention your assumptions and cite references wherever used. If you need to add assumptions not listed above, show them in a general list of assumptions above your calculations.
Do not try to contact any vendor, utility, or company. No collaboration allowed, and irrelevant recommendations will cause a penalty of points.
