Specifications

1.Yield will be enhanced
2.Smelting time reduced
3.Energy saved a lot

Qingdao antai heavy industry

Furnace Flue Gas Capturing Technology

At present, the matured method of furnace flue gas capturing is semi-closed cover type and diversion roof cover type. The diversion roof cover is actually combined by one semi-closed hood and roof cover.

Semi-closed cover

The semi-closed is composed of fixed cover and movable cover, the movable cover can remove to the top of transformer. Semi-closed cover is widely used in dust removal system of medium and small electric furnaces in recent years. Compared with roof cover, the advantages are: the system drafting amount is smaller, flue gas collection efficiency is higher, investment and operating costs are relatively low. Semi-closed cover can completely capture the flue gas during furnace smelting, however, its capturing efficiency of flue gas produced material loading and unloading is not satisfied and opening, closing of the semi-closed cover has certain impact for the smelting period.

Diversion roof cover

The diversion roof cover is composed of diversion cover and roof cover.

The diversion cover is composed of fixed cover and movable cover, the former is installed at material unloading side and at the back of furnace, while the latter is installed at the top of transformer behind furnace. The movable diversion cover will be moved to the top of transform during material feeding and be moved out of furnace proper during smelting. The fixed and movable diversion covers surround electric furnace, forcing the flue gas arising within the diversion cover area. After flue gas rises to the diversion cover hole, the distance between gas and cover is only 5m, which minimize the bad effect of transverse flue gas. After commissioning, the movable cover can be fixed and only be moved during maintenance so as to decrease operation procedures. The roof cover is inner and outer double layers structure. The inner cover will collect the flue gas flowed out from diversion cover along diffusion corner, while the outer cover will collect the overflowed flue gas.

The diversion roof cover can remove flue gas produced in smelting, which is environmental friendly and easy to be operated, but the disadvantages are that air discharging amount is large and investment, operation cost is high.

flue gas collection technology of LF furnace

At present, the mature methods of furnace flue gas capturing are semi-closed cover type and furnace cover type. The structure of semi-closed cover is same with that of electric furnace. The furnace cover is that the top of water cooling furnace cover of LF furnace is equipped with one round gas exhausting cover, which spares electrode incoming and outgoing holes in the middle position, the furnace cover and electrode moves simultaneously. Another kind of furnace cover is that gas exhausting pipes are connected to the sides of water cooling furnace cover. There is 100 mm space between furnace cover and gas exhausting pipe.

Flue gas flow produced during LF furnace smelting is not large, which can be eliminated by the furnace cover, besides, the dedusting system is of low investment and operation cost.

Flue gas collection technology of AOD furnace

Compared with the common converter, AOD converter has the following characteristics: long smelting time, low oxygen blowing intensity, low decarburization speed and low CO content; therefore the flue gas recovery of AOD converter is .of little value.

Flue gas of AOD converter is collected by the movable cover. The cover top is made of stainless steel plate and the cover inner wall is painted with refractory material. The CO-containing flue gas produced during smelting, fully combusts with induced air at the furnace hole, resulting high temperature flue gas up to 900 ~ 1600 °C. AOD converter will produce certain dust during feeding and steel solution unloading. At the mean time, the high temperature flue gas should be cooled down by mixed air, so that AOD converter is specially equipped with the secondary dust collection device, which uses diversion roof cover, and mix the secondary flue gas with roof exhaust gas.

Performance comparison of various dust collector

	Furnace cover	Rotary cover	Large closed cover	Roof cover	Traveler passing cover
Gas discharging outside of the furnace	Processed	Processed	Processed	Processed	Processed
Gas discharging inside of the furnace	Not processed	Processed	Processed	Not processed	Not processed
Dust collection rate	50%	70%	95%	40%	85%
Whole process collection	Poor	Poorer	Better	Good	Good
Affect the operation	Poor	Poor	Better	Good	Good
Occupied space	Small	Smaller	Bigger	Big	Big
Endurable capacity	Poor	Poorer	Better	Good	Good
Noise and heat radiation proof	Poor	Better	Good	Poor	Poor
Air flow dealing	Small	Medium	Larger	Higher	Larger
Installation cost	Low cost	Medium	High	Highest	Higher
Operation cost	Low cost	Medium	High	Higher	Higher