Impact of Poor Microbiological Control

Uncontrolled microbiological growth in cooling and process water systems is a multi-billion £ problem for businesses each year. The primary cause of this expensive problem is biofilm.

BioFilm content imageTypical problems caused by biofilm in cooling water systems

Biofilms form when bacteria and other microorganisms found in the bulk water attach to exposed surfaces and begin to produce a mass of biopolymers known as extracellular polymeric substance (EPS). The EPS provides a sticky, protective barrier that allows complex communities of bacteria to thrive and exponentially grow. Bulky, biofouling deposits can quickly form as the EPS traps dirt, corrosion by-products, and other debris suspended in the water, leading to blockages.

The protective barrier formed by biofilm is hard to penetrate with traditional biocide programs, making it very problematic in systems. Once established, biofilms can cause a multitude of problems including flow restrictions, reduced heat transfer, microbiologically-influenced corrosion (MIC) and promote the proliferation of serious pathogens like Legionella. These issues can lead to poor heat transfer efficiency associated with increased greenhouse gas emissions, lost production, even catastrophic equipment failures and system shut-downs.

Current Monitoring Methods

Monitoring for microbiological control is an essential part of the water treatment program. Typical monitoring methods like dip slides or laboratory plate cultures only measure the planktonic (free floating) bacteria in the water sample from the system and not the bacteria growing within the biofilm, which can account for as much as 90% of all microbial activity in a system! The absence of bacteria using these methods does not necessarily indicate that a system does not have a biofouling problem.

Innovations in Microbiological Monitoring

To address the missing link in microbiological monitoring in the water treatment industry, Chem-Aqua developed a new biofilm monitor. The bioDART® is an automatic, real-time monitor that measures a systems potential to form biofouling deposits. A system’s biofouling index (BFI) reading provides a quantitative and predictive indicator of its potential to form biofilm that can be used to gauge microbiological control. Sudden spikes or rapid increases in the BFI can be indicators of high levels of biofouling bacteria or changes in system operations.

Examples include:

  • Offline chillers being brought online
  • Upsets in biocide feed
  • Mechanical upsets or process leaks (Glycol, process water, other contaminants)

bioDART Banner

On line monitoring with bioDART allows Chem-Aqua to identify high risk events and early warning signs of biofouling  and work in partnership with our customers to fix problems before serious and costly problems occur.

In recognition its potential to be used a simple, yet effective predictive tool to detect and control biofilm , in 2019 bioDART was nominated winner of the prestigious R&D 100 award.

Find out more about Chem-Aqua’s bioInnovations and how they helped our customers improve their operational efficiencies and cut costs here.


Written by: John Bychkowski and Simona Vasilescu