Optimization of Process for Total Recovery of Aluminum From Smelting Slag 2. Removal of Aluminum Sulfate

Abstract

This paper continues the previous investigations regarding the technology for the Aluminum (Al) recovery as Al sulfate from black Al slag. Leaching is the next compulsory step in the Al extraction process. The paper studies the influence of mother solutions´ (MS) recirculation resulted from the process within the system over the quality of Al sulfate and the siliceous residue (R) and, the aluminum nitride (AlN) hydrolyses in the leaching process. The optimum parameters determined are: *the leaching yield of the slag that registers values between 56÷66 % and for the soluble Al 96-97%; *the quality of the products obtained from this technology which have significant coagulation properties; *the AlN decomposition which continues at the leaching phase but is lower than those achieved in the washing process. Besides, the (R) from the leaching process was inertized employing binder slag-cement or slag-lime into the proportion 7:3 binders: (R) ratio. The flow sheet of entire process is also presented. The experimental results were ultimately the purpose for the feasibility study, the economical analysis and the designing of a pilot plant (600t/year Al slag).

Recovery of Aluminum from Industrial Waste (Slag) by Melting and Electrorefining Processes

“…Generally, the Al slag is a mixture of Al oxide, metals, chloride, fluoride, alloying elements and salts from the fluxing agent, nitride, carbide, sulfides, and other substances, which are the result of molten Al reactions with other elements present in the melting system. In contact with rain water, they can react emanating inflammable or toxic gases, such as methane and ammonia, or may become soluble, infiltrating the soil and finally reaching the groundwater; therefore, they are considered dangerous for the environment [10]. The main purpose of this project is to understand the fundamental knowledge of recovery of aluminum from industrial waste in Iraq and the limitation of recovery.…”

Technological Solution for the Treatment of Wastewater Resulting from Autochthonous Aquacultures in Order to Protect the Marine Water Quality

“…This paper shows the results of the research conducted on the development of a technological solution for the treatment of wastewater resulting from a culture of autochthonous shrimp species (Palaemon elegans). A contemporary theme related to the possibility to obtain an adequate quality of the effluents was addressed simultaneously with the use of compounds (aluminium sulphate) obtained through the recovery of metallurgical slags from secondary aluminium industry [13][14][15]. Palaemon elegenans, popularly known as rockpool shrimp ( fig.…”

“…The substances used for wastewater treatment were: aluminium sulphate recovered from metallurgical slags using a Romanian patented method [13,14], commercially available aluminium sulphate Kemira ALG (EN 878:2004, Kemwater Cristal Comp.) considered as benchmark and a flocculation agent Floerger FR 1023 (anionic polyelectrolyte).…”