Key points of silico-manganese alloy process

(1) Technical conditions of raw materials:

①Requirements for chemical composition of manganese ore:

Alloy grade

Manganese ore particle size: 10 mm~80 mm, less than 10 mm not more than 10%; ②Coke requirements: should meet the metallurgical coke conditions, fixed carbon ≥ 84%, ash ≤ 14%; particle size requirements 5 mm ~ 25 mm. The CaF2 in fluorite is ≥70%, and the particle size is 5 mm~40 mm. The requirements for raw materials are related to the capacity of the electric furnace.

(2) Requirements for smelting parameters: Under the conditions of a submerged arc furnace with a transformer rated capacity of 12,500 kVA: ①The commonly used voltage level is 143 V; ②A suitable electrode working end length is 1700 mm~2000 mm; ③Maintain three-phase current and voltage balance; ④ Control proper slag basicity, control dual basicity R2=0.5~0.7, SiO235~43%, MgO5~9% in the slag; ⑤The material surface has good air permeability, uniform fire, and large area sinking of the charge balance (closed electric furnace makes The pressure in the furnace is stable) and the electrode is inserted deep and steadily into the charge. This is an important indicator of the normal furnace conditions during the smelting process; ⑥Sufficient amount of reducing agent, insufficient reducing agent, will easily lead to slag turning, load fluctuations and insufficient power transmission. The content of Si and Mn in the alloy decreases. [3]

Silico-manganese alloy is produced by reducing manganese oxide and silicon dioxide in manganese ore (including manganese-rich slag) and silica with charcoal in a submerged arc furnace. The production of manganese-silicon alloy is carried out in a submerged arc furnace, using carbonaceous reducing agent, manganese ore, manganese-rich slag, sintered manganese ore, roasted manganese ore and silica as raw materials, and lime, dolomite, fluorite, etc. as fluxes for continuous production in the electric furnace