Preventing Legionnaire’s Disease – Process Water Cooling

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Process Water Cooling To Prevent Legionnaire’s Disease

Process water is water that is the result of any industrial process or has come into contact with an industrial process. Different processes produce different process water however the common issue is that they all need to be dealt with. If the process involved the water becoming heated, then it is necessary to use Process Water Cooling to deal with this before it is released into the environment.

Where Is Process Water Cooling Needed?

A lot of industries use processes that make the water involved hot, however the energy industry and chemical refineries are the main places where the technique is needed. This due to a lot of processes being involved in energy production mostly involving the combustion of raw materials which results in water as a by-product.

Process cooling equipment means that the cycle can be made both more efficient and also more environmentally friendly be cooling the steam and process water and recycling it allowing it to be reused. This in turn means less energy is required and less is spent on water bills as well as not draining as much water from the mains system. This is usually done via wet cooling towers which cool the by-products before releasing them into the air.

What are the problems with wet cooling towers?

Wet cooling towers used for process water cooling are at risk of allowing bacteria to build up inside them due to the nature of the environment. One of these potential bacteria is Legionella which can lead to deadly legionnaires disease. If the right conditions emerge, then due to a process called  drift (also known as windage) this can make its way into the air and get into the nearby environment.

Bacteria build up is an issue, as if it makes its way into the environment the Legionella bacteria can cause serious health problems in humans – especially those that are more vulnerable in the form of Legionnaires disease. This is a type of lung infection which results in fever, chest pains and breathing difficulties, from breathing in droplets of contaminated water

An incident in France in 2006 resulted in Legionella escaping from a petrochemical plant using wet cooling towers near Calais and causing 86 cases of Legionnaires – 21 of which resulted in fatalities.

What Measures Can Be Taken During Process Water Cooling to Prevent The Spread Of Legionnaires?

One thing that has been done already is that government agencies in a large number of countries have put steps in place to ensure that it is compulsory for water in a wet cooling tower to be treated  with bactericidal agents to ensure that bacteria doesn’t develop. This in theory should limit the growth of any harmful bacteria that could make its way into the environment.

Alongside this, it has become common for special fills to be used in a cooling tower. These are designed to further prevent the growth of bacteria n a cooling tower. Additionally, adding in a drift eliminator, will prevent any bacteria that does form from being easily carried by wind and making contact with the outside world.

Drift Eliminators prevents excess water produced during the process water cooling from becoming airborne and getting into the environment, as was the case in France. Drift Eliminators can have a number of forms, and are usually also treated with bactericidal chemicals to prevent any spread of disease. If the Process Water Cooling Equipment is treated appropriately, then incident s such as the one in France or more recently in Scotland are less likely to occur.

Larger process water cooling systems need additional precautionary measures, as their complex systems allow for bacteria to spread more easily and grow more rapidly. If this is the case than the dangerous effects can be more widespread.

Therefore in industries where a lot of water technology is used, especially where there is process water cooling taking place on a big scale, then having the right process cooling equipment is important, because it is a legal requirement and also because it is for the greater good of the workers of the plant and the environment in general.