Framed Drift Eliminator Replacement on Three BAC VXC Cooling Towers

We completed a drift eliminator replacement on three BAC VXC 250 cooling towers at an ice manufacturing facility in West Sussex, as part of our cooling tower refurbishment service.

The challenge

Over time, the existing drift eliminators had become brittle and damaged, and drift was visibly escaping from the towers. On top of that, the straps holding them down were green with algae and starting to fray.

Drift eliminators are the last line of defence in any cooling tower. Consequently, in this condition they no longer met the requirements of ACOP L8.

Our drift eliminator replacement process

• First, we worked alongside the site’s water treatment provider, taking one tower at a time to limit disruption.
• Next, we removed and disposed of the old drift eliminators and failing straps.
• After that, we installed new stainless steel supports and T-bar air seals.
• We then built and fitted high efficiency cellular PVC drift eliminators in stainless steel framed cassettes, sized to fit each tower.
• Finally, we repeated the work across all three towers and issued full documentation.

When drift eliminators fail, treated water and any bacteria it carries can leave the tower as aerosol. Fortunately, replacing them is a simple, effective fix.

The result

Why it matters to facilities managers

• Compliance with ACOP L8: the new eliminators exceed ACOP L8 requirements, with a drift loss of less than 0.0005% to keep aerosol release to a minimum.
• Lower Legionella risk beyond the site: above all, capturing drift inside the tower protects staff, neighbouring buildings and the public from aerosol carried off site.
• No drift bypass: engineered cassette sizes and T-bar air seals give a tight fit to the tower casing, and as a result, air cannot bypass the eliminators.
• Built to last: stainless steel frames give maximum edge protection, and in addition, the robust welded cellular construction stands up to handling and years of service.
• Easier maintenance, low pressure drop: cassettes are easy to lift out for inspection and cleaning, and a low pressure drop also helps keep fan energy in check.

Drift eliminator replacement FAQs

How often should drift eliminators be inspected?

We check drift eliminators at every routine inspection and at every clean and disinfection. HSG274 Part 1 recognises six-monthly cleaning and disinfection as a common precautionary approach. However, your Legionella risk assessment, operating conditions and any evidence of fouling should set the actual frequency. For this reason, our cooling tower maintenance visits always include a condition check of the eliminators and their fixings.

What are the signs drift eliminators need replacing?

First of all, look for brittle or cracked media, gaps between sections and sagging or failing straps. In addition, heavy fouling, algae or visible drift around the tower all show the eliminators are no longer doing their job.

Can drift eliminators be replaced without shutting the site down?

Usually, yes. On multi-cell or multi-tower sites we work on one unit at a time, just as we did here. As a result, the site keeps cooling capacity throughout the works.