Cold-pressing pallet production process of chromium fine ore

Abstract

The invention discloses a cold-pressing pallet production process of a chromium fine ore. The production process includes the following steps that 1) raw materials are pre-homogenized, and by weight, 75-95 parts of chromium fine ore with the grain size less than or equal to 5mm, 1-5 parts of quicklime and 10-14 parts of dedusting powder are mixed uniformly to be processed; 2) by weight, 90-99 parts of the raw materials, 1-5 parts of agglomerant and 0.5-5 parts of solid additive in the raw materials after being pre-homogenized are sufficiently mixed to form mixtures; 3) cold-pressing palletizing is carried out on the mixtures to form pallets; 4) the pallets are taken out and naturally aired to form finished product pallets, or the pallets are conveyed into drying equipment to become the finished product pallets. The chromium fine ore, layered material distribution and pre-homogenization are carried out on the quicklime and the dedusting powder which are needed in high carbon ferrochrome production through a loader, the quicklime absorbs moisture in the chromium fine ore, so the moisture content of the fine ore is reduced, and a needed moisture content range for the finished product pallets is obtained.

Description

technical field [0001] The invention relates to the technical field of metal smelting, in particular to a production process of chrome powder ore cold-pressed pellets. Background technique [0002] At present, the methods for pretreatment of chromium powder ore mainly include cold-pressed pelletizing method, SRC method, DRC method, Outokumpu method, COBO method, sintering method and so on. Advantages of SRC method: add reducing agent in the pellets to pre-reduce chromium ore, save coke and smelting electricity, and increase production; disadvantages are large investment, more power consumption for grinding, which is harmful to chromium ore and coal Powder requirements are strict and production management is difficult. The characteristics of the DRC method: the difference from the SRC method is that the pellets are not reduced in the rotary kiln but in the rotary bed reduction furnace; the pelletizing part of this method is the same as that of the SRC method, but the compreh...

AI Technical Summary

Problems solved by technology

Outokumpu method: The characteristic of this process is that no carbon reducing agent is added to the ball, only a small amount of dust and coke powder is added, the power consumption is low, the output is high, and it is very useful for high gangue and low grade; disadvantages: complex process, management quite difficult

At present, the production process of cold-pressed pellets in my country's metallurgical industry includes the following steps: After the chromium ore powder is pretreated (dry explosion, sieving), the particle size <3mm enters the batching bin by a belt conveyor, and the coke powder and The slaked lime powder is hoisted into the batching bin by the crane, and the material is weighed according to the ratio by the electronic weighing hopper, and then sent to the mixing mill for mixing and grinding, during which binder is added, and the mixed grinding material is sent to the counter roller by the elevator Ball briquetting mechanism balls, the pellets made are sent to the grate machine by the cloth belt conveyor, and pre-consolidated in the gas with a CO2 content of 8% and a temperature of about 200°C in the machine, and then enter the consolidation tank. For final consolidation, the cold-pressed pellets made by this process have a large decrease in grade, poor high temperature resistance, high pulverization rate, and the production and application process of the pellet binder is complicated, which affects the production output. Chromium powder in the production process The moisture in the mine is difficult to control, resulting in poor quality of finished balls