The invention provides a closed non-fixed
anode direct-current submerged arc furnace. The closed non-fixed
anode direct-current submerged arc furnace comprises a furnace body, a furnace cover, an
electrode column
system, a feeding
system, a
flue gas leading-out
system, a power supply system, a cooling water system and a hydraulic system, wherein the furnace body is used for containing furnace burden, the
electrode column system is used for heating and melting the furnace burden by utilizing a direct-current arc, comprises a
cathode and an
anode, and the
cathode and the anode can freely adjustthe depth inserted into the furnace burden; and the furnace cover used for ensuring the sealing of the furnace body is arranged above a furnace shell of the furnace body, and the furnace cover and thefurnace shell are subjected to sealing treatment. According to the closed non-fixed anode direct-current submerged arc furnace, a submerged arc furnace gas with relatively high CO concentration is generated after the submerged arc furnace is sealed, can be used as fuel for power generation,
roasting, hot-blast stove and the like after being purified and recycled, so that the utilization value isextremely high, and the comprehensive
energy consumption can be reduced; and almost no air enters a
hearth, the oxidation of the
electrode is slow, the loss is low, both the
cathode and the anode canmove up and down, are inserted into the
solid furnace burden, not in direct contact with a high-temperature molten liquid, the structure is simple, the equipment is reliable in operation and
failure rate is low.