In the process of swimming pool water treatment, selecting the appropriate flocculant is crucial for ensuring the cleanliness and safety of the pool water. Flocculants effectively remove suspended particles and impurities, improving water transparency. However, different stages of pool treatment require different types of flocculants. Proper selection of flocculants not only improves the quality of the pool water but also reduces operating costs. This article provides a detailed exposition of the flocculants required for swimming pool water treatment, helping readers understand more about pool water treatment.
Cleaners that can be used for each step
Stopping and preventing algae growth
Copper sulfate (Blue Vitriol) can be used. It is an algicide, appearing as asymmetric blue crystals or powder, which easily dissolves in water. Besides its bactericidal and inhibitory effects, it can also give the pool water a light blue color, similar to seawater. Use 2-3 kilograms per 1000 cubic meters of water, once or twice a month, or when small insects or algae are observed. After applying copper sulfate, wait for 2 hours before proceeding to the next step.
Adjusting pH value (acidity and alkalinity)
Sodium carbonate (baking soda) and hydrochloric acid can be used for pH adjustment. Sodium carbonate is a white or fine granular substance, soluble in water, and is alkaline. In low pH conditions, 15 grams per cubic meter of water can raise the pH by about 1 degree Celsius. Hydrochloric acid, being strongly acidic, is used when the pH value exceeds 8.2, at 5-10 kilograms per 1000 cubic meters of water. The ideal pH value for swimming pools is between 7.5 and 8.0.
Sterilization and disinfection
The specific reagents and methods for this step vary depending on the water quality conditions and specific requirements. Common disinfectants include aluminum chloride, bleaching powder, etc.
Aluminum chloride is an inorganic disinfectant that works by altering the protein structure of bacteria, providing a bactericidal effect and adapting to different water environments. Normally, add 1-2 kilograms of aluminum chloride per 1000 cubic meters of water. However, excessive use can cause water turbidity, so it is important to control the dosage.
Bleaching powder (calcium hypochlorite): A common swimming pool disinfectant, its main component is calcium hypochlorite, which has a rapid bactericidal effect. First, mix bleaching powder with water in a certain ratio to make a solution, and then evenly disperse it into the pool. Typically, use ten to fifteen kilograms per thousand cubic meters of water. Bleaching powder is sensitive to pH value and temperature, so these factors should be considered when using it. Also, store bleaching powder away from heat or flammable materials.
Sedimentation
Poly Aluminum Chloride (PAC) can also be used. PAC, an inorganic polymer with 30±1% AL₂O₃ content, appears as colorless or yellow resin granules, and its solution is a colorless or yellow-brown transparent liquid. The solid product contains 20-40% aluminum chloride, more than 30% yellow PAC, and about 10% liquid product. It can remove suspended particles, iron, cadmium, fluorine, radioactive pollution, floating objects, etc., from the water, being five times more effective than alum. Use 5 to 10 grams per cubic meter of water.
Therefore, in the process of swimming pool water treatment, it is important to select and use flocculants appropriately to ensure the cleanliness and safety of the pool water. Pool managers must choose the right type and amount of flocculant based on the specific water quality conditions and treatment requirements of the pool. Additionally, swimming pool water treatment is not a simple task but a systematic project. While fully utilizing the role of flocculants, it should be combined with other water treatment reagents and equipment such as disinfectants, pH adjusters, and filtration devices to ensure the overall quality and safety of the pool water.