What is the cooling tower water treatment programme?
Cooling tower water treatment system minimises scaling and fouling in the cooling tower system. It is an essential step of the process to keep cooling systems running fine. The water treatment programme for cooling towers typically involves removal of detrimental impurities from the feed water, circulation water or blowdown.
Components of cooling tower water treatment system
The cooling tower components depend on the feed water quality and circulatory water chemistry with the needed water quality for the specific cooling tower. However, a basic cooling tower water treatment system generally includes the following components and steps:
Cooling tower makeup water intake
Makeup water or the evaporated and leaked water from the cooling tower is firstly exerted from its source be it raw water, city water, city treated effluent, well water, in-plant wastewater recycle or any other surface water source. The quality of the source water will determine if you would need the water treatment here. If the system requires water treatment at this part of the cooling tower process, then it is the technology that will remove hardness and silica from the water or stabilize and adjust the pH.
This stage of the process allows the proper treatment to optimize the tower evaporation cycles and cut back on the water bleed rate to drain.
Filtration and ultrafiltration
Running the cooling tower water through some kind of filtration removes any suspended particles like sediment, turbidity and some organic matter. Doing it early on in the process ensures the removal of suspended solids upstream can keep membranes and ion exchange resins from fouling later on in the pretreatment process. The suspended particles can be removed down to under one micron depending on which type of filtration you are using for the procedure.
Ion exchange or water softening
There are ways to soften the hard water when you find the source/makeup water has high hardness. The hardness of water is caused due to the presence of compounds like calcium and magnesium.
High hardness in your makeup water may demand the treatment for the removal of hardness. The process of softening the water will require a softening resin instead of lime, strong acid cation exchange process where the resin is charged with a sodium ion and as the hardness penetrates it has a higher accord for calcium, magnesium and iron so it will attract and grab that molecule and release the sodium molecule into the water.
This step of the process typically makes use of chemicals like corrosion inhibitors for neutralizing acidity and protecting metal components, algaecides and biocide for reducing the growth of microbes and biofilms, scale inhibitors for preventing contaminants from forming scale deposits.
Ensuring that your cooling tower manufacturer provides a rigorous treatment before reaching this stage can reduce the amount of chemicals needed in treating water at this point in the process. However, this is considered ideal, as too many chemical treatments can be expensive.
A side-stream filtration unit is accommodating when it comes to removing any problematic contaminants if the cooling tower water will be recirculated through the system. These contaminants may have entered through drift contamination or leak. As a matter of fact, about 10% of the circulating water will filter through if your cooling tower water treatment system needs to have a side-stream filtration.
Don’t Miss to Read: The Process Of Industrial Cooling Tower Water Treatment
The final step of the treatment required for cooling tower water treatment is blowdown treatment. Plants will choose to recycle and recover the water through post-treatment in the form of ion exchange or reverse osmosis, especially in those places where water might be insufficient. This process allows the liquid and solid waste to be concentrated and removed, and the treated water can be returned to the cooling tower and reused.
You may have to ensure the discharge your system creates meets all regulatory requirements if the water from your blowdown needs to be discharged. There is a possibility of having larger sewer connection fees in specific areas where water is scarce, and demineralization systems may be a cost-effective solution in such cases as they help reduce the cost to connect water and sewer lines. The cooling tower blowdown discharge has to meet local municipal discharge regulations if your outflow is returned to the environment or publicly owned treatment works.
Appropriate water treatment is extremely important for cooling towers. Tower tech India is one of the leading cooling tower manufacturers in India, providing an ideal solution for your cooling tower needs. With the experience of over three decades, we are capable enough to offer you a detailed guideline for cooling tower requirements. Reach out to us for your cooling tower needs like water treatment programme in the system.