Reconstruction of the vanadium-pulp leaching and filtration section in the chemicals division of the ferroalloys shop at the Chusovoi Metallurgical Plant

Abstract

The main bottleneck in the chemicals division of the Chusovoi Metallurgical Plant is the leaching and filtration section.There are two main reasons for the problems being encountered in the operation of the section:1) the use of filtration equipment of an old design (drum-type vacuum filters with an internal filtering surface), which consumes a substantial amount of time in replacing the filter cloth while producing a filtrate with excess suspended solids and a filter cake with excess moisture;2) the use of a three-stage leaching system that employs a large number of pieces of equipment -vacuum filters, mixing tanks, collectors, settling tanks, and concentrators -and does not achieve the required performance indices.With the market for ferrovanadium now growing, the leaching and filtration section has become an impediment to increasing product output. This has become especially apparent in the last two years. To resolve the problem, the plant has enlisted the help of specialists from the Vostochnaya Ukraina Scientific-Industrial Association to determine the feasibility of filtering the pulp with a new generation of press filters (chamber-type press filters of type FKMg, with top-suspended slabs). Scientific research on this subject has determined the following: the productivity and number of press filters required; their cyclograms; the possibility of combining the processes of filtration, washing, and leaching of the vanadium and drying of the filter cake in One unit. The results of this work were used to generate initial data for the design of the filtration and leaching section. One of the organizations involved in developing the specifications was the institute Giprostal' (Kharkov, Ukraine) -the lead organization involved in the original design of existing ferroalloys shop No. 2.To reduce capital costs, it was decided to build the new section in the building that currently houses the third roasting furnace after the existing equipment and metal structures have been dismantled and the building has been renovated.The design of the new filtering and leaching section, completed in 2000, provides for the following operations: filtering of the pulp created during water leaching; a first washing with water; sulfuric-acid leaching in the recirculation regime; a second washing with water; drying of the filter cake with air. All of the operations will be performed in one unit in the automatic regime. The plan also entails an eventual increase in production capacity to 30% above the present level. The equipment will be installed in a compact configuration at one level. The facility that houses the existing leaching section will be freed for other uses. In particular, it might be used as the site for a complex that can treat waste water. The work stations will be equipped in accordance with the requirements of the production process and the organization of the various tasks.The new equipment can also be used for other technologies, including a changeover to water leaching. 2000.Chusovoi Metallurgical Plant and the United...