| There is a significant amount of glass fiber adhering to the cathode surface deposit during the suspension electrolysis of lead paste from used lead-acid batteries.This affects the crystallization and electrical conductivity of the material,which in turn impacts lead recovery.Diaphragm fibers are broken down into very tiny fibers and combined with the lead paste as the used lead-acid batteries are mechanically crushed.Sieving and cleaning the elements do not separate them.High concentrations of sulfuric acid and soluble impurity ions like sodium and iron are present in the electrolyte used in the lead paste electrolytic recovery process.These ions are difficult to separate and purify due to their complicated chemical makeup.However,the most widely used concentration recovery technique for recovering sulfuric acid requires a lot of energy and is laborious in its steps,making it unable to better resource the use of diluted sulfuric acid.In this paper,we select the processes of flotation to separate the fibers in lead paste and diffusion dialysis to recover the purified sulphuric acid from lead paste electrolyte,which is helpful to improving the efficiency and precision of subsequent suspension electrolytic regeneration of lead paste and realizing the regeneration preparation of dilute sulphuric acid by-product.The main focus of the investigation is the impact of dispersant and trapping agent on flotation effect;diffusion of sulfuric acid ions and impurity ions is examined through diffusion dialysis simulation experiments to serve as a foundation for industrial acid recovery simulation calculations;and the safety of the sulfuric acid recovery process is also assessed.Through multi-level flotation experiments,it was demonstrated that the tannic acid-dodecylamine flotation agent system had a substantial impact on the separation of fibers by analyzing the wettability,particle size distribution,and adsorption mechanism of the flotation products.The tannic acid-dodecylamine flotation solution in the strong acid system was more enhanced by fiber adsorption,selectively removing the fibers;at a trap concentration of 90 mg/L,the flotation efficiency was maximum and the fiber recovery was 85.36%.Lead paste electrolyte waste underwent static diffusion dialysis with an acid recovery of roughly 46.1% for one part and 75.2% for two sections.The dialysis simulation experiments confirmed that the diffusion dialysis method has a positive impact on acid recovery and impurity removal.In the dialysis procedure,greater temperatures promoted the diffusion of iron and sodium ions while inhibiting the diffusion of sulfate ions.While higher sulfuric acid concentrations hindered sodium ions from diffusing,the concentration of sulfuric acid had no impact on the diffusion of iron ions.Based on the experimental data parameters,a two-stage cyclic dialysis experiment with the same concentration difference was used to simulate an ideal condition,and the sulfuric acid recovery was 91.75%.This needed a total sulfuric acid residence duration of 12 hours.Impurity sodium ions leaked at a rate of 7.3%,while iron ions leaked at a rate of 9.7%.The permeation coefficients based on static diffusion dialysis experiments were obtained from the simulated dynamic diffusion dialysis acid recovery experiments,and an empirical model of the recovered acid concentration was created for a particular LE-He AM-I membrane by utilizing gauge analysis and semi-empirical analogy.It serves as a reference for the industrial recovery of a variety of waste acids and serves as a useful manual for the investigation of inter-membrane ion movement behavior.Semi-quantitative analysis of the impact of the hazards in the diffusion dialysis process on the safe operation of the system by means of pre-hazard analysis and hazards analysis of working conditions,and suggests safety measures for hazards associated with the diffusion dialysis procedure,providing a scientific basis for the stable and safe operation of the diffusion dialysis acid recovery process. |
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