Alkaline Pressure Oxidation Processing Lead And Copper Gun Technology Research

In view of the existing lead-copper matte process which is high power consumption and serious pollution, this paper developed and studied on alkaline pressure oxidative processing of lead-copper matte. It succeeded in the recovery of copper, selenium, lead, silver, and no waste gases and slags, opening up a new channel for the treatment of lead-copper matte, at the same time, the clean production have been achieved.In the early studies, we proceeded to a conclusion through pressure oxidative experiment in several different alkaline systems, and chose the sodium hydroxide system as the alkaline system.The influence of Six factors, which are beginning temperature, excess ratio of sodium hydroxide, pressure of oxygen, Stirring Speed, time and V/W, was investigated in the single factor experiment of sodium hydroxide pressure oxidative processing. It was concluded that the optimized condition was beginning temperature 125℃, excess ratio of sodium hydroxide 0.08, pressure of oxygen 0.3-0.8MPa, Stirring Speed 1000r/min, V/W 4:1 and time 1.5h. In this condition, the leaching ratio was S98.03%, Se96.96%, Pb4.15%, As0.45%, respectively.Carried on the single factor experiment of sulphuric acid leaching into alkaline slag which was obtained from pressure oxidative processing under the optimized conditions, the influence of the concentration of sulphuric acid, the ending pH of leaching and the temperature was investigated. It was concluded that the concentration of sulphuric acid was an important factor, which determining the trend of the main metallic element and impurities. The method of controlling ending pH of sulphuric acid solution acquired remarkable achievement. The optimized condition of sulphuric acid leaching was ending pH 2.5, temperature 60℃, at this time, the leaching ratio of copper was almost 98.52%, the leaching ratio of iron and silver was just 1.66%,0.72%,in the slag, the content was Cu 1.44%, Pb 54.57%,Ag 11.28%, Fe 0.4136%,lead and silver were enriched by two times. The influence of the current density, temperature, the beginning concentration of acid and the concentration of ferri ion for current efficiency was investigated by the electrolytic deposition of copper sulphate solution. The optimized condition was current density 320A/m2,temperature 50℃, when the electrolytic voltage rised smartly, it was the end of electrolytic deposition.Generally, the ending concentration of copper ion is 15g/L, the purity of cathode copper is more than 99%.According to the result of 1L autoclave experiment, the plant test was developed, it contained the alkaline pressure oxidative processing of lead-copper matte, the sulphuric acid leaching of the alkaline leached slag, the electrolytic deposition of copper sulphate solution and the returning leaching of the residuary electrolytic solution. The result of the plant test was basically consistent to which of laboratory.