Improved boiler performance through thermodynamic modeling.

摘要

This thesis explores the possibility of improving the boiler's performance via thermodynamics analysis. A second law analysis that can be applied to any industrial thermal process that does not have condensate return to the high temperature reservoirs was developed. Furthermore, an economizer model, based on heat exchanger theory, was developed to simulate heat recovery from hot gases exiting the boiler's stack.; The calculated exergy rates from both the boiler and economizer have determined that the stack gas temperatures have a great impact on the performance. The stack temperature also affected the consumption of the fuel and the amounts of useful heat exhausted into the environment. The average cost savings that resulted from using an economizer to recover 57% of the maximum heat rejected was averaged at {dollar}8. Also, the ratio between the cost savings and steam produced was averaged at {dollar}0.20 per 455 kg of steam. The total cost savings for the eight days considered were {dollar}939. Therefore, it was demonstrated that heat recovery is an important factor that can help improve boiler efficiency and productivity.