Roasting pretreatment process for extracting vanadium pentoxide from high-carbon scherbinaite-containing coal mine and vanadium pentoxide extracting method

Abstract

The invention discloses a roasting pretreatment process for extracting vanadium pentoxide from a high-carbon scherbinaite-containing coal mine and a vanadium pentoxide extracting method, which comprise the following steps that: the stone coal scherbinaite is used as raw materials, the raw materials are crushed and pressed into blocks and are dried, then, the materials are continuously put into a tunnel kiln capable of regulating the air volume and the pushing speed to be roasted, the temperature is controlled between 400 DEG C and 1000 DEG C in the roasting process, the roasting time lasts 7hto 40h, and the pretreatment process is completed after the roasting. The roasting products are crushed, and then, vanadium pentoxide products are obtained sequentially through leaching, neutralization, oxidization, impurity removal, enrichment, ammonium salt vanadium deposition and calcination. The process has the advantages that the application range is wide, the energy consumption is low, the heat value utilization is sufficient, the equipment investment is low, the environment pollution is little, and the like. The method is suitable for being applied to the vanadium pentoxide extraction from the high-carbon scherbinaite-containing coal mine.

Description

technical field [0001] The invention belongs to the technical field of rare metal smelting, and in particular relates to a pretreatment process and an extraction method for extracting vanadium pentoxide from stone coal mines. Background technique [0002] Stone coal is a kind of matrix-corroded anthracite existing in the ancient formations of Sinian, Cambrian and Silurian. It is formed under reducing conditions in shallow sea after the death of low-level organisms such as fungi. Its main characteristics are The ore has high density, compact structure, low calorific value, and is difficult to burn completely. The grade and carbon content of stone coal vanadium vary greatly, generally V 2 o 5 The content of V is between 0.13% and 1.2%, rich ore V 2 o 5 The carbon content can reach more than 2%; the carbon content is 2% to 20%. Vanadium is an important strategic material resource with important uses. More than 80% of vanadium is used in the steel industry to manufacture sp...

AI Technical Summary

Problems solved by technology

[0005]1. Sodium roasting method: also known as salt roasting method, is the oldest stone coal roasting method and vanadium extraction technology. The carbon and vanadium oxidation equipment uses salt as the roasting additive, the roasting time is more than 12 hours, the roasting temperature is 800-850°C, the roasting energy consumption is high, and a large amount of Cl2, HCl and other toxic gases are released. Seriously pollute the surrounding environment; after roasting, the vanadium in the roasting material is leached with water, the vanadium leaching rate is only about 60%, and the final yield is about 45%. Carbon, potassium, aluminum, silicon and other resources are completely ignored, and the pollution of the three wastes is serious. This law has been explicitly banned by the state.

[0006]2. Boiling furnace combustion decarburization, rotary kiln roasting method: use the calorific value of stone coal to burn and decarburize in a fluidized fluid furnace, and the slag after decarburization passes through the rotary kiln Oxidation and roasting at high temperature and heat preservation, and then leaching with dilute sulfuric acid to extract vanadium. Due to the large fluctuations in carbon content and calorific value in stone coal, it is difficult to burn stably. It must reach a higher calorific value before it can be decarburized in a fluidized fluidized furnace. Due to the short time in the furnace for the decarburization process, the low-priced vanadium in the stone coal has not been oxidized in place, and the decarburized stone coal slag needs to be oxidized and roasted at about 900°C in equipment capable of high-temperature roasting such as rotary kilns. 2 to 3 hours to obtain a better vanadium leaching rate. Due to the complexity of the process, the matching of equipment and process has not yet achieved good results.

[0008]4. Rotary kiln decarburization roasting and dilute acid leaching method: This method uses a rotary kiln as a carbon-containing stone coal decarburization and oxidation roasting equipment, and the stone coal is crushed into Powder, or made into small balls and then added continuously from the kiln tail after drying, from the kiln head spray coal powder combustion or burn water gas to heat the stone coal mine to about 900 ° C, decarburization and oxidation roasting are completed in one equipment, due to the material in the rotary kiln The heat conduction and air oxidation mass transfer are greatly affected by the thickness of the material layer and the properties of the material itself. The high temperature decarburization speed of the rotary kiln is not ideal, the processing capacity is low, and due to the difficulty of thermal control, it is difficult to control the decarburization and roasting. Speed ​​and final effect, material sintering, kiln closing, etc. are prone to occur, resulting in low vanadium leaching rate of roasted materials, especially for high-carbon stone coal resources, it is technically difficult to achieve decarbonization and oxidation roasting in the same kiln