Cause analysis of high electrode paste consumption in closed calcium carbide furnace
1.1 Quality of electrode paste
The quality of electrode paste directly affects the baking quality and consumption index of electrode, and also affects the safe and stable operation of furnace.
Ash content is a strictly controlled quality index, because it has a direct impact on the baking speed, conductivity, oxidation resistance, sintering density and consumption speed of the electrode. It is particularly important to strictly control the ash quality index of the electrode paste. At the same time, avoid the misunderstanding that the lower the ash, the better. It is not that the lower the ash, the better. The ash is too low and the baking strength of the electrode is not enough, Too high ash content is easy to cause hard breaking of the electrode, which will increase the consumption of electrode paste. Reasonably control the product quality of electrode paste to ensure the long-term stable operation of calcium carbide furnace.
1.2 Electrode accident
Due to improper operation during electrode adjustment, electrode accidents are easy to occur in the roasting electrode stage, which destroys the heat balance of electrode roasting and is very difficult to re-establish the normal roasting order. Moreover, under the condition of high current, the electrode with forced roasting has high quality porosity and poor mechanical strength, and its consumption speed will be accelerated. Due to the frequent hot shutdown caused by electrode accident, the output of calcium carbide is reduced, and the consumption of electrode paste is greatly affected. Electrode accident is a main factor affecting the high consumption of electrode paste.
1.3 Electrode paste column height
The ideal paste column height control range of calcium carbide furnace is 3.5m ~ 4.5m from the upper end of conductive element, and the pressure per unit area of electrode paste is generally 0.35kg ~ 0.45kg.
If the electrode paste column is added too high, in addition to the increased load of the electrode holder, which is not conducive to the safe production of the calcium carbide furnace, it is mainly prone to the overall liquefaction in the electrode shell, resulting in the particle precipitation during the baking process of the electrode paste. When it is added again, it is easy to destroy the normal sintering procedure of the electrode paste, resulting in the deterioration of the electrode working condition and the increase of the consumption of the electrode paste.
The control of electrode paste column is too low, which is easy to cause over speed sintering, and the sintering delamination tensile strength attenuation of electrode is easy to occur in the electrode shell, which lays a hidden danger for the hard breaking accident of electrode; Because the control of electrode paste column is too low, the bearing pressure per unit area decreases, the sintering density of electrode decreases, and the consumption of electrode paste is bound to increase.