Phosphating pickling burnishing Water purification plants
Phosphating is a chemical process where the surface of the processed metal is modified to create a chemical resistance to corrosion and to prepare the product for other possible treatments such as industrial painting.
Phosphating uses several chemical solutions, zinc, nickel phosphate manganese, etc..
Burnishing is a chemical treatment that colours the metal and provides protection against oxidation creating an improvement in the aesthetic appearance.
Pickling is a chemical treatment that removes the surface layer of metals, pickling eliminates the oxide layer preparing the material in the best possible way to deal with the subsequent processes both protective passivating and galvanic coating or electrochemical surface treatment.
All these chemical processes develop polluted wastewater that must be suitably treated with water purification plants designed to create a specific purification treatment.
In these industrial sectors the most used treatment plant is the continuous chemical-physical purification plant or the chemical-physical purification plant in batch, these purification plants consider the high salinity that contains these wastewaters to be treated such as sulphate nitrite and nitrates, and adopt the correct chemical contrast reactions to ensure the compliance of the wastewater or their recovery even partially.
Ion exchange resin plants are also used, these water treatment plants are used in the last stages of processing to optimize the quality of the washings and eliminate any trace or saline stain on the processed pieces.
The water purification plants are completed in some specific cases by vacuum water evaporation plants, these treatments are carefully evaluated as they are resolutive to eliminate the problem of concentrates and wastewater with very high salinity and pollution.
The water treatment plants normally proposed in the galvanic sector are:
- Continuous chemical and physical purification plants
- Plant stages for the abatement of sulphate nitrate sulphate salts
- Chemical-physical water treatment plants in batch
- Sludge dewatering plants with filter presses
- Ion exchange resin purification plants with total recycling counter-flow ion exchange resins
- Plants for concentration or vacuum evaporation of eluates and concentrates