ANALYSIS OF THE EVAPORATIVE TOWERS COOLING SYSTEM OF A COAL-FIRED POWER PLANT

Abstract

The paper presents a theoretical analysis of the cooling system of a 110 MW oal-fired power plant located in central Serbia, where eight evaporative towers ool down the plant. An updated research on the evaporative tower cooling ystem has been carried out to show the theoretical analysis of the tower heat nd mass balance, taking into account the sensible and latent heat exchanged uring the processes which occur inside these towers. Power plants which are sing wet cooling towers for cooling condenser cooling water have higher design emperature of cooling water, thus the designed condensing pressure is higher ompared to plants with a once-through cooling system. Daily and seasonal hanges further deteriorate energy efficiency of these plants, so it can be oncluded that these plants have up to 5% less efficiency compared to systems ith once-through cooling. The whole analysis permitted to evaluate the optimal onditions, as far as the operation of the towers is concerned, and to suggest an mprovement of the plant. Since plant energy efficiency improvement has become quite common issue today, the evaluation of the cooling system operation was onducted under the hypothesis of an increase in the plant overall energy fficiency due to low cost improvement in cooling tower system.

Keywords

Dates

  • Submission Date2012-04-26
  • Revision Date2012-06-06
  • Acceptance Date2012-09-12

DOI Reference

10.2298/TSCI120426176L

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