Electroplating wastewater comes from plating cleaning water, Water Treatment Chemicals，waste plating solution, equipment cooling water and other wastewater.
Characteristics of sewage, this kind of wastewater is generally strong acid water quality, water quality is complex, the composition is not easy to control, which contains chromium, cadmium, nickel, copper, zinc, gold, silver and other heavy metal ions and cyanide, some belong to carcinogenic, teratogenic, mutagenic highly toxic substances.
After these heavy metals enter the water body, they have an amplified effect on the food chain, and can accumulate in some organs of the human body to cause chronic poisoning and endanger human health.
In the treatment of electroplating wastewater, because the wastewater contains many expensive heavy metals, if the heavy metals in the wastewater as a resource to recover, not only to solve the pollution of heavy metals, but also has a certain economic benefits.
At present, the commonly used heavy metal wastewater treatment methods mainly include chemical precipitation, reduction, adsorption, membrane separation, coagulation, ion exchange, electrochemical method and so on. It is found that the polyacrylamide selection results of the wastewater treatment are directly related to the ph value of the wastewater, because most of the wastewater is carried out under strong acid conditions.
The best use of polyacrylamide for electroplating wastewater and its precautions
1, polyacrylamide through a small test to determine the best model, and the best amount of the product.
2, the product is prepared into 0.1% (refers to solid content) concentration of aqueous solution, with no salt neutral water is appropriate.
3. When dissolving water, evenly sprinkle the product into the stirred water, and the appropriate heating (<60℃) can accelerate the solution.
4, solid products with polypropylene woven bag packaging, lined with plastic bags, each bag 25kg.
5, solid products to avoid scattering on the ground, to prevent the product after absorbing moisture to make the ground slippery.
6, preparation of PAM aqueous solution, should be in enamel, galvanized, aluminum or plastic barrels, can not be prepared and stored in iron containers.
7, when dissolving, it should be noted that the product should be evenly and slowly added to the dissolver with stirring and heating measures, solidification should be avoided, the solution is prepared at the appropriate temperature, and the mechanical shear should be avoided for a long time. It is recommended that the mixer 60-200 RPM /min, otherwise it will lead to polymer degradation and affect the use effect.
When most of the electroplating wastewater is under strong acid conditions, we generally choose cationic type, coagulation under alkaline conditions, and generally choose ultra-high molecular weight anionic polyacrylamide as coagulant aid.
It should be noted here that due to the characteristics of electroplating wastewater itself, its ph value is relatively high, before selecting the agent, it is best to select the water sample for beaker experiment, and determine the selection and dosage.
Each thousand tons of electroplating wastewater to be treated generally requires 20-100 kg of product. The amount of polyacrylamide treatment electroplating wastewater is about 2-10 grams. The number of polyacrylamide agents used in electroplating wastewater should be determined by considering the turbidity of sewage, the molecular weight of polyacrylamide agents, and the specific situation of the water impurities. Other
Water Treatment Chemicals Aluminum Sulfate ,Polyaluminum Chloride
Henan Hongze Environmental Protection Technology Co., Ltd
