1. Industrial circulating water treatment-overview
1. Industrial circulating water treatment content:
Water treatment program design; water quality testing; water treatment agent formulation adjustment; provision of water treatment agents; industrial circulating cooling water treatment (sterilization and algae, corrosion and scale inhibition) full service.
2. The business scope includes:
Petrochemical plant circulating cooling water treatment, thermal power plant circulating cooling water treatment, steel plant circulating cooling water treatment, chemical fiber plant circulating cooling water treatment, chemical plant circulating cooling water treatment and other industrial enterprise cooling water system water treatment.
2. Industrial circulating water treatment-main issues
1. The main problems arising during the operation of circulating water:
Scale: As the circulating cooling water evaporates continuously during the cooling process, the salt concentration in the water is continuously increased, and the solubility of some salts is exceeded and precipitated. Common scales include calcium carbonate, calcium phosphate, and magnesium silicate. The texture of scale is relatively dense, which greatly reduces the heat transfer efficiency. A scale thickness of 0.6 mm reduces the heat transfer coefficient by 20%.
Dirt: Dirt is mainly composed of organic matter in the water, microbial colonies and secretions, silt, dust, etc. The texture of the dirt is soft, which not only reduces the heat transfer efficiency but also causes corrosion under the scale and shortens the service life of the equipment.
Corrosion: The corrosion of circulating cooling water to heat exchange equipment is mainly electrochemical corrosion, which is caused by equipment manufacturing defects, sufficient oxygen in water, corrosive ions (Cl-, Fe2+, Cu2+) in water and mucus secreted by microorganisms Factors such as fouling, the consequences of corrosion are very serious, even if the heat exchanger and water pipeline equipment are scrapped in a very short time without control.
Microbial slime: Because the circulating cooling water has sufficient oxygen, suitable temperature and eutrophic conditions, it is very suitable for the growth and reproduction of microorganisms. If it is not controlled in time, it will quickly lead to water quality deterioration, odor, blackening, and a large amount of slime in the cooling tower Deposition or even clogging, the cooling effect is greatly reduced, and equipment corrosion is intensified. Therefore, the circulating cooling water treatment must control the reproduction of microorganisms.
3. Industrial circulating water treatment-solutions
Industrial circulating water treatment is to add chemicals-water treatment chemicals to the water. The water treatment chemicals contain corrosion inhibitors, which can control corrosion and protect equipment; contain scale inhibitors to prevent scaling; contain biocides, which can Prevent the formation of microorganisms and algae.
Various water treatment agents, such as corrosion and scale inhibitors, dispersants, and bactericides are often added to industrial cooling circulating water systems and refrigerant water systems to stabilize the scaling ions in the water. The principle is through chelation, Complexation and adsorption and dispersion, so that calcium and magnesium ions can be stably dissolved in water through chelate complexation, and have a good dispersion effect on colloids such as iron oxide and silicon dioxide. Because the corrosion inhibitor forms a water-insoluble or water-insoluble protective film on the metal surface, it hinders the hydration reaction of metal ions or the dissolved oxygen reaction, and inhibits the corrosion reaction. This method is currently the most commonly used method for industrial circulating water treatment and central air-conditioning water treatment. It is also the most widely used and technologically mature method in industrial water treatment. Practice has proven to be an effective and economical method.
Industrial circulating cooling water treatment can increase the concentration of circulating water and reduce the amount of water supplement. It is done manually or automatically. Because industrial circulating water treatment is a dynamic process, it must be carried out under the state of chemical detection and monitoring. Therefore, the water quality must be analyzed regularly and the amount and variety of water treatment chemicals must be adjusted.