Electroplating wastewater source plating bath cleaning water, waste plating solution, equipment cooling water and other wastewater.

   The characteristics of sewage, such wastewater is generally strong acid water, complex water quality, difficult to control ingredients, including chromium, cadmium, nickel, copper, zinc, gold, silver and other heavy metal ions and cyanide, some of which are carcinogenic, teratogenic, Mutant highly toxic substances.

   After entering the water body, these heavy metals have a magnifying effect on the food chain, which can be accumulated in certain organs of the human body to cause chronic poisoning and endanger human health.

   When treating electroplating sewage, because the wastewater contains many expensive heavy metals, if the heavy metal in the wastewater is recovered as a resource, it not only solves the pollution of heavy metals, but also has certain economic benefits.

   At present, the commonly used heavy metal wastewater treatment methods mainly include chemical precipitation method, reduction method, adsorption method, membrane separation method, coagulation method, ion exchange method, electrochemical method and the like. It was found that the results of polyacrylamide selection for treating this type of wastewater have a direct relationship with the pH of the wastewater, since most of the wastewater is under strong acid conditions.

   The best polyacrylamide use method and precautions for electroplating wastewater

1. Polyacrylamide is tested through small tests to determine the best model and the optimum amount of the product.

2. The product is formulated into an aqueous solution with a concentration of 0.1% (referred to as solid content), and neutral water containing no salt is preferred.

3. When dissolving water, spread the product evenly into the stirred water. Accelerate the solution by heating (<60 °C).

4. Solid products are packed in polypropylene woven bags lined with plastic bags, 25kg per bag.

5, solid products to avoid spreading on the ground, in order to prevent the product from slipping after the moisture absorption.

6. When preparing PAM aqueous solution, it should be carried out in enamel, galvanized, aluminum or plastic drum. It should not be prepared and stored in iron container.

7. When dissolving, care should be taken to slowly add the product to the dissolver with stirring and heating measures. Avoid solidification, prepare the solution at a suitable temperature, and avoid mechanical shearing for a long time. It is recommended that the stirrer be 60-200 rpm, otherwise the polymer will be degraded and the effect will be affected.

   When most of the electroplating wastewater is under strong acid conditions, we generally use a cationic type to coagulate under alkaline conditions, and an ultrahigh molecular weight anionic polyacrylamide is generally used as a coagulant.

   It should be noted here that due to the characteristics of the electroplating wastewater itself, the pH value is relatively high. Before selecting the agent, it is best to select the water sample for the beaker experiment, and determine the selection and dosage.

   Electroplating wastewater to be treated per kiloton typically requires 20-100 kg of product. The amount of polyacrylamide treated electroplating wastewater is about 2-10 grams. The specific polyacrylamide agent for electroplating wastewater should be determined by considering the turbidity of the sewage, the molecular weight of the polyacrylamide agent, and the impurities in the water.