Optimizing Cooling Tower Performance: Loss Analysis and Efficiency Enhancement Strategies

Abstract

Cooling tower are essential components in industrial heat rejection systems, where performance losses directly affected operational efficiency and energy consumption. This study presents a performance analysis of a mechanical draft cooling tower, focusing on identification and evaluation of major losses. Parameters such as water inlet and outlet temperature, wet-bulb temperature, and flow rates were measured under load condition. Losses due to evaporation, Drift, blow down, and heat exchange inefficiencies were quantified. Results show that these losses contribute to overall efficiency reduction. Based on the findings, improvement strategies such as effective use of drift eliminator, precise fan speed control, and setting blade angle are proposed. Implementation of these measures can enhance efficiency; reduce water wastage and low operating cost. The study provides a practical framework for diagnosing cooling tower losses and guiding efficiency enhancement in industrial applications.

Introduction

Cooling towers are crucial components in power plants, refineries, HVAC systems, and industrial processes. They dissipate low-grade heat from water into the atmosphere, reducing the need for fresh water and improving operational efficiency. Effective cooling tower performance depends on heat transfer efficiency, airflow, fill design, water losses (drift, evaporation, blowdown), and energy use (fan/pump power).

Project Objective

This study analyzes performance losses in cooling towers and explores strategies to enhance efficiency, reduce water and energy consumption, and extend service life. It involves:

• Benchmarking performance under current operating conditions

• Measuring thermal, water, and energy losses

• Implementing optimization measures

• Evaluating improvements in cost and efficiency

Performance Assessment

Cooling Tower Details (RGCCPP, Kayamkulam)

• Type: Induced draft, counterflow

• Cells: 8

• Cooling range: 11°C

• Approach: 5°C

• Fill: Film (PVC)

• Water flow: 23,000 kg/hr

• Year Commissioned: 1999

Measured Performance

• Range = 8.89°C (Inlet: 43.44°C, Outlet: 34.55°C)

• Approach = 8°C (Outlet: 34.55°C, WBT: 26.55°C)

• Effectiveness = 52.63%

• Heat Load = 173.53 kW (592,103 BTU/hr)

Loss Analysis

1. Evaporation Loss

• Formula: 0.001 × Water Flow × Temperature Range

• Result: 3,585.6 L/day

2. Drift Loss

• Before eliminator (0.05%): 201.72 L/day

• After eliminator (0.002%): 8.06 L/day

3. Blowdown Loss

• With C.O.C = 4:
  Blowdown = 1,195.2 L/day

4. Total Make-Up Water Required

• Sum of all losses:
  Total = 4,788.86 L/day

Fan Power Consumption

Light Shaft

• Electric Power Input: 0.692 kW

Heavy Shaft

• Electric Power Input: 0.734 kW

Conclusion

The study on cooling tower performance revealed that evaporation loss is the primary contributor to total water loss, followed by blow down and drift. Optimization through controlled blow down, effective water treatment and improved drift eliminators can significantly enhance efficiency and reduce makeup water demand. These strategies ensure better thermal performance, lower operational costs and promote sustainable operation. The study confirms that targeted optimization leads to reliable and eco-friendly cooling tower performance.

References

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Copyright

Copyright © 2025 Ajith Krishnan K. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.