Raw material screening of trolley furnace

Raw material screening of trolley furnace can improve the raw material situation. Through the screening of raw materials under the tank, raw materials are the basis. The good and bad screening is closely related to the furnace condition. Add a set of raw ore vibrating screen (once the raw ore was not screened directly into the furnace) to screen the powder below 5 ~ as far as possible. Control the feeding quantity of coke and sinter from 20kg / s to 10kg / s, extend the screening time as much as possible and improve the screening effect.

Strengthen the screening under the tank. The foreman on duty is required to check the raw fuel four times per shift and make records. The winch man cleans the screen surface more than twice per shift.

Formulate detailed process operation rules and try to unify the three shifts

(1) Set up a furnace condition treatment team, select three experienced foremen with high operation level to carry out three shifts of operation in the whole plant, and the criterion adjustment shall be determined after discussion by the team;

(2) Normal operation:

A. The control of air volume and pressure is mainly stable, and blind air charging is not allowed. The blast furnace is in short pressure, and it should be withdrawn in time;

B. Constant pressure difference operation, try to control the upper limit of ventilation index in the normal range;

C. The furnace temperature shall be properly high controlled, the temperature of molten iron required shall not be lower than 1460, the low furnace temperature shall be strictly prohibited, and an analysis meeting shall be held if any;

D. Alkalinity control, generally not higher than 1.10, control between 1.05-1.10.

Manual cleaning of trolley furnace:

The washing of the trolley type furnace is carried out by the way of combining the dispersive adding of human washing agent and the collective adding of human washing agent. The washing agent is manganese ore and fluorite, and the proportion is 2:1.

Add people to wash the furnace separately, add manganese ore, fluorite evenly to each batch of materials, the quantity accounts for about 5% of the ore batch, distribute to the edge of the furnace, and continue to wash the furnace for one week.

Gather and wash the furnace irregularly according to the furnace condition. The intention is to recover the furnace condition quickly, improve the air permeability of the material column and reach the active hearth. In the process of handling the abnormal furnace condition of No.5 blast furnace, gather and wash the furnace 5 times, add 20 vehicles (2000kg per vehicle) of coke purification each time, with fluorite and manganese ore. the load is calculated as 1.0. After washing the furnace, remarkable effect has been achieved. The temperature of the furnace body rises again, and water is used When the temperature difference reaches the normal range, the surrounding temperature difference tends to be uniform.

Adjustment of loading criteria

The main reason of high-temperature furnace is the lack of coke in the center for a long time, resulting in poor air permeability of the central column, and the lack of wind energy for a long time, resulting in severe accumulation of the center. Therefore, the idea of firmly opening the center in the distribution and air flow control, the main methods are as follows:

(1) Reduce the ore batch weight. The ore lot was reduced from 24 tons to 23.1 tons.

(2) Coke and ore move 2 degrees to the center as a whole, loosen the margin properly, and ensure the smooth running.

(3) The coke quantity in the center of the furnace is added, and the coke ore platform is reduced at the same time.

With the addition of central coke amount, the central material column gets loose, the central temperature of the furnace increases, the air volume increases, the use of gas improves, and the furnace condition improves rapidly. Through the above measures, the furnace condition of No In a good case, the service factor is stable above 3.5V (M3. D), and the coke ratio is lower than 400kg / T.