In the production process of closed calcium carbide furnaces, electrode paste consumption directly impacts production efficiency and cost control. To help you better understand this critical aspect, this article delves into the seven key factors influencing electrode paste consumption, offering insights to optimize production management and enhance economic performance.
The control of electrode immersion depth is central to electrode management in calcium carbide furnaces, essentially involving the management of the length of the three-phase electrodes. The immersion depth refers to the actual insertion depth of the electrode into the furnace, which is the hidden part of the electrode’s working length. Currently, there is no high-tech instrument or precise method to accurately measure the immersion depth, and it is still estimated based on the range of electrode position changes. Although the measurement process is cumbersome and imprecise, the immersion depth is inversely proportional to the consumption rate of electrode paste. The ideal immersion depth should be determined based on local raw material conditions, process control characteristics, and operational strengths, moving away from the traditional belief that greater depth ensures furnace stability. Excessive immersion depth can disrupt the thermal balance, slow the descent of raw materials, reduce power density in the reaction zone, and negatively impact product quality and output. A scientifically reasonable immersion depth should be maintained at 1.1 to 1.25 times the electrode diameter.
The carbon materials used in calcium carbide production vary widely in physical and chemical properties. If the volatile content in carbon materials is estimated manually using probes, deviations can accelerate electrode erosion and directly affect electrode paste consumption. Currently, high-volatile carbon materials like blue coke and anthracite dominate the domestic market, while petroleum coke is less suitable due to its high sulfur dioxide content. High-volatile materials, primarily composed of low-temperature hydrocarbons, not only cause material caking but also accelerate electrode erosion. Therefore, when using blue coke and anthracite, it is essential to adjust the carbon mix and electrical control parameters, particularly managing electrode immersion depth and consumption rate. Our company uses a blend of blue coke and coke at a 7:3 ratio.
The quality of calcium carbide directly reflects the furnace’s reaction conditions. High-quality products indicate optimal furnace temperature, proper electrode length control, and balanced heat distribution, signifying stable furnace operation. Conversely, low-quality products suggest significant fluctuations in electrode immersion depth, disrupted heat distribution, and increased electrode paste consumption. The calcium carbide formation reaction relies heavily on resistive heat, with the arc playing a minor role in the molten pool. Therefore, the carbon in the electrode participates in the chemical reaction, and its consumption must be factored into the raw material mix. When the furnace operates at high temperature, high quality, and high carbon ratio, electrode consumption is relatively low. Otherwise, carbon deficiency leads to poor product quality and accelerated electrode paste consumption.
During normal operation, unplanned equipment failures or production accidents leading to hot shutdowns are inevitable, and even planned shutdowns pose challenges for electrode maintenance. Hot shutdowns often result in inadequate electrode protection, causing surface oxidation and bonding with semi-finished products, which can lead to electrode breakage. Particularly during water leakage incidents, electrode erosion and immersion severely hinder the restoration of ideal working conditions. Frequent opening of observation doors to measure electrode length or handle surface crusts and ash can damage door seals, allowing air ingress, reducing furnace CO concentration, and causing severe electrode oxidation.
Frequent hot shutdowns disrupt the normal sintering process of electrodes. Since heat conduction is the primary heat source for electrode sintering, the furnace’s molten pool cools slowly after a shutdown, causing continued upward sintering of the electrode. This leads to over-sintering, severe arcing upon restart, and a vicious cycle of repeated shutdowns and startups, inevitably increasing electrode breakage and consumption rates.
By scientifically managing the factors influencing electrode paste consumption, you can not only improve the operational efficiency of your calcium carbide furnace but also effectively reduce production costs. We hope this analysis provides valuable insights for your production practices, helping your business stand out in a competitive market.
