Procedure, with its corresponding installation, for the integrated use of the pirate ashes. (Machine-translation by Google Translate, not legally binding)

摘要

Procedure with its corresponding installation, for the full use of the pyrite ashes, characterized in that in order to separate the non-ferrous elements and to obtain an agglomerated or pelletized material, oxidized or pre-reduced, the first phase is carried out, the calcination with separation of arsenic in which the pyrite ash is calcined in a mixture with, from 2 to 5% of sodium chloride and from 2 to 5% of carbonic material, in a rotating countercurrent furnace to hot gases that obtained by burning methane or a low-quality fuel, with appropriate excess air, so that the CO/CO2 ratio in the exhaust gases and adjusted to the conditions of the composition of the load must be 1.4 to 1.6, while the load runs through the furnace zones in a duration that is adjusted so that a zone from 1000 to 1200ºC is traveled by the material from 50 to 60 minutes and the second phase gives the chlorine volatilization in which the cleaned load is impregnated with a supplement of Ca Cl2 and in case of nee d ground to obtain a granulation that shows in 70 to 80% under 0.03 millimeters per particle, and the agglomerate or the pellets in countercurrent to the combustible gases that, by burning methane in excess air in a rotary kiln with a predetermined speed, they run through the kiln for a duration of 0.5 to 1 hour and are heated with 100 to 120ºC per minute to approximately 1100ºC, and combustible gases they enter the exit zone of the oven at 1100 to 1150ºC and leave the entrance zone at 600 to 700ºC, then cooling the agglomerated or pelletized material with an acceptable content in S, As, Pb, Cu, Zn in a tray, where it is countercurrent with reduced gases that contain CO and H2 and that are preheated up to 700 to 900ºC and introduced tangentially in the exit area of the rotary kiln, together with the combustible gases, so that an at weakly oxidizing atmosphere in the exit area of the oven and in the cooling tray in order to obtain the finished oxidized product, or a reducing atmosphere in order to obtain a reduced finished product, whereby the atmosphere can be reinforced by introducing it into the upstream furnace with agglomerated or pelletized charge and with an amount of 400 kg/tonne of coke or coal product, with suitable granulation, and gases extracted from the first phase of pyrite ash processing they are selectively cleaned by methods known per se in order to recover Pb, As, S and the gases extracted from the second phase of chlorine volatilization are cleaned in a known way dry or wet in order to keep all the volatile non-ferrous metals to be later recovered by well-known hydrometallurgical methods. (Machine-translation by Google Translate, not legally binding)