Treatment method for removing cadmium in electroplating wastewater

Abstract

The invention discloses a treatment method for removing cadmium in electroplating wastewater.Wastewater passes through a water-collecting well, a coarse screen, a primary settling tank, a pH value adjusting pool, a tea seed meal-aeration flotation purification system, a heating and contracting pool, an alkalizing and settling pool, a secondary pH value adjusting pool, a secondary settling pool and a water purifying pool to be treated.According to the treatment method, the cadmium ion flotation characteristic of tea saponin in tea seed meal is utilized creatively, in the condition that the pH value is 5.5-6.5, the saponin in the tea seed meal is combined with cadmium ions in the wastewater to form a molecular structure prone to air floatation, then a great number of air bubbles are introduced to the water through compressed air aeration, and the air bubbles carry the saponin combined with the cadmium ions to be floated on the water surface and gathered to form foams, so that the cadmium ions in the wastewater are removed in a targeted mode; meanwhile the tea seed meal is residues obtained after camellia seeds are subjected to oil expression, cost is low, the tea seed meal is easy to obtain, and material cost of wastewater treatment can be greatly lowered.

Description

technical field [0001] The invention relates to a treatment method for removing cadmium in electroplating wastewater, which belongs to the field of wastewater treatment in environmental protection. Background technique [0002] Heavy metal pollution in water has become one of the environmental problems of widespread concern in the world today. Cadmium is a very common heavy metal ion in industrial electroplating wastewater. It is enriched through the food chain and brings great harm to animals and humans. The "Bone Pain Disease" incident in Toyama, Japan, was that the local aluminum factory discharged cadmium-containing wastewater into the water body. Residents ate cadmium-containing rice and drank cadmium-containing water for a long time. Excessive accumulation of cadmium in the body caused renal dysfunction and bone Calcium is replaced by cadmium, which softens the bones and causes fractures. Cadmium also has carcinogenic, teratogenic, and mutagenic toxic effects. [0...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is the high cost and short service life of the immobilized carrier

[0016] At present, the existing cadmium-containing electroplating wastewater treatment methods have shortcomings such as slow response, narrow scope of application, many control conditions, high cost and easy to cause secondary pollution.

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