What Is Bac Cooling Tower Drift Eliminators

BAC (Baltimore Aircoil Company) cooling tower drift eliminators are critical components designed to capture and return water droplets entrained in the exhaust air, minimizing water loss, chemical loss, and environmental impact.

Below is a clear, BAC-specific technical overview.

1. Function of BAC Drift Eliminators

* Reduce drift loss to typically ≤ 0.001–0.002% of circulating water flow

* Prevent water carryover to:

 * Nearby equipment

 * Structures

 * Walkways

* Maintain water chemistry and reduce makeup water demand

* Help towers meet ASHRAE / CTI drift limits

2. Where Drift Eliminators Are Located

* Installed above the fill and below the fan stack

* Positioned in the air discharge path

* Final component air passes through before leaving the tower

3. BAC Drift Eliminator Types

3.1 PVC Multi-Pass Drift Eliminators (Most Common)

Design features:

* Multi-pass blade profile forces air to change direction multiple times

* Water droplets impact blade surfaces and drain back into the tower

Materials:

* Rigid PVC

* UV-stabilized and corrosion-resistant

Typical performance:

* Drift rate: **≤ 0.001%**

* Low pressure drop

* Long service life

3.2 High-Efficiency Drift Eliminators

Used when:

* Towers are near sensitive areas

* Local regulations require ultra-low drift

Features:

* More blade passes

* Slightly higher pressure drop

* Drift rates as low as ≤ 0.0005%

3.3 FRP or Stainless Steel Eliminators (Special Applications)

* High-temperature water

* Aggressive chemicals

* Industrial process cooling

4. Drift Eliminators by BAC Tower Type

Crossflow Towers (Series V, FXV, CXV)

* Vertical airflow

* Drift eliminators mounted at air discharge

* Removable panel design for maintenance

Counterflow Towers (FXT, VT)

* Air moves upward

* Drift eliminators installed above spray system

* Designed to withstand higher air velocity

5. Key Design Characteristics

* Precision blade spacing

* Integrated drainage channels

* Resistance to:

 * UV exposure

 * Biological growth

 * Chemical attack

* Matched to:

 * Fan velocity

 * Tower thermal duty

6. Common Problems & Causes

Issue	Likely Cause
Visible water plume	Broken or missing eliminators
Excess drift	Improper installation
High fan power	Fouled or warped eliminators
Water loss	Aged or cracked PVC blades

7. Inspection & Maintenance

* Inspect at least once per year

* Check for:

 * Cracks or brittleness

 * Missing blade sections

 * Misaligned panels

* Clean with low-pressure water

* Replace panels in sets to maintain uniform airflow

8. Replacement & Retrofit Guidelines

* Always match:

 * BAC model

 * Cell size

 * Airflow rate

* Avoid mixing old and new eliminator designs

* Ensure proper sealing to prevent air bypass

* Aftermarket eliminators must meet CTI drift certification

9. Drift Eliminators vs Fill (Common Confusion)

Item	Drift Eliminator	Fill
Purpose	Capture water droplets	Heat transfer
Location	Air discharge	Water/air contact zone
Effect on cooling	Indirect	Direct
Replacement frequency	Longer	Shorter