Study On Removel Of Binary Components Of Copper And Nickel Ions From Dilute Solution By Foam Separation

Electroplating is a fundamental technology in machinery manufacture,the pollution produced by this technology made people worry,a lot when it promoting the development of economics.So,urgent measures of effective wastewater treatment need to be implemented as early as possible.Foam separation was paid more attentions for its unique advantages of lower cost,simple operation,especially for it can adapt to the change Of water quality and lower concentration solution.In this paper,removal of binary components of copper and nickel ions from dilute solution by foam separation was studied.Different kinds of surfactants were selected by orthogonal design in this paper.The result showed that anion surfactant has a better result than other surfactants.As the flow rate of gas water is 200L/h and the dissolved pressure is 0.24MPa under alkaline condition, the range of sodium dodecyl sulfate when removal of Cu²⁺ and Ni²⁺ were 3.98 and 3.73, and the removal efficiency of Cu²⁺ and Ni²⁺ were 93.50%and 92.15%.Since,the surfactant of sodium dodecyl sulfate was selected as the separating agent during the experiment.Based on orthogonal experiments,The effect of concentration of surfactant,pH value, flow rate of original water,flow rate of dissolved gas water and amount of flocculant were studied by single factor experiment,and the best removal process was determined.The result showed that as the concentration of surfactant is 15mg/L,pH is 11,flow rate of original water is 80L/h,flow rate of dissolved gas water is 250L/h and amount of Al(SO₄)₃ is 15mg/L,the removal efficiency of Cu²⁺ and Ni²⁺ can reach 92.46%and 93.14%.The macrokinetics of removal of Cu²⁺ and Ni²⁺ by foam separation was studied. Based on the equivalence of foam separation with the chemical reaction process,the foam separation was equivalenced to be a chemical reaction process.The equivalence reaction was determined to be one order reaction and the rate constant was k=0.289 through experiment.And the residence time distribution was also studied.The average residence time of t m is 9.089,variance ofσ² is 55.2.23,dimensionless comparison time variance ofσ_θ² is 0.668.Then,the mathematic model of removal efficiency of foam separation with equivalence reaction rate constant and residence time distribution density function was established.The mathematical expression of residence time distribution density function was fitted.