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Benefits associated with filtering cooling tower water with liquid bag filters.


Improving the efficiency of cooling towers in many ways can be accomplished by a very simple process.

Filtering the cooling water and removing particulates capable of potential damage and contamination is a primary goal for many industries world-wide. Bag filters are a common and cost effective option for this type of application.

Usually, water with a percentage of glycol is filtered by using bag filters to clean the non-contact cooling liquid. This method is very effective in eliminating contaminants and particulates in open cooling ponds and older cooling systems that have never had filtration.

Whether it is an older cooling system or new cooling system removing particles of 10 micron and larger are needed to keep equipment downtime, poor performance and higher operating costs at a minimum. Pipe scale and a lack of clean makeup water can not only introduce unwanted solid material into the system but increase bad performance, costly repairs and added downtime.

Liquid filter bag systems are commonly used method for removing particles because they can achieve the filtration level easily and are cost efficient. Bag filters are sized accordingly to the housing and strainer basket they are supported by. Filter media can be made in various types of fabrics. Under normal conditions, bags should be changed infrequently because they have a large dirt holding capacity.


The flexibility of using filter bag housings for older systems that have never had any filtration, is they can use the step down approach in the filter system. The application can start with a 100 or larger micron fabric media to initially capture the larger particulates. Over time, when the bags are lasting longer in the housing bags with smaller micron fabric can be used to continue capturing the finer particulates until the proper 10 micron bags can be maintained. The inside to outside flow inside the housing prevents the contaminants from exiting the filter during operation and removal of the filter change out.

Other applications, certain types of specialty bags can be used to maximize the bag filter effectiveness:

Oil-Absorption Filter bags can be used in certain cooling systems to prevent the buildup of oil. The bag material is constructed of a lofted Polypropylene fiber that attracts and holds on to oil particles. The material swells as it captures oil that it comes in contact with. As the bag material swells, the filtration efficiency of the bag increases. Oil absorption bags are used in applications where oil molecules are between 25 – 500 ppm.

Pleated Filter bags are used to increase the amount of time in between filter bag changes. The surface area of the filter is increased 5-10 times of a standard filter bag giving it have a higher level of dirt holding capacity reducing downtime for filter servicing. This option reduces the operating expenses and employees time for servicing filtration units and production downtime.

Magnetic Rod Inserts for filter bags to capture metals and ferrous materials will reduce equipment downtime, potential equipment failure, maximizes the life of the disposable bags and filtering efficiency. Magnetic Rods can remove more mass than a filter bag alone which in turn increases the operating time in between filter changes. When the filter bag needs changing, the rod is simply removed and wiped clean with rag. The material wiped from the rod can be then disposed of and the cleaned rod can be reinserted with the new bag for continued and repeated use.

To find out more information on filter bag uses and other filter housing applications, please contact Vince Paglino, Industrial Specialist at Filter Pure Systems, Inc 800-942-7873

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