Types of graphite cathode carbon blocks

The cathode carbon block is a carbon block made from high-quality anthracite, coke, graphite, etc. It is used as the cathode of an aluminum electrolytic cell. It is laid at the bottom of the electrolytic cell and is also called the bottom carbon block. The cathode carbon block has the dual functions of conducting electricity and forming the inner lining of the electrolytic cell. The requirements for aluminum electrolysis production specify that the cathode carbon block should have high temperature resistance, resistance to molten salt erosion, good electrical and thermal conductivity, high mechanical strength, good thermal shock resistance, and strong resistance to sodium erosion. This is conducive to energy conservation in aluminum electrolysis production and the extension of cell lifespan.

The types of cathode carbon blocks in China are basically divided into three categories based on the quality requirements of the product, the selected raw materials, and the process conditions: ordinary cathode carbon blocks, semi-graphite carbon blocks, and graphite carbon blocks. Ordinary cathode carbon blocks are mainly made from anthracite that is calcined at 1250-1350℃. The resistance of ordinary cathode carbon blocks is 40-60 μΩm.

Physical and chemical indicators are as follows:

1. Ordinary aluminum use cathode carbon blocks:

Ash content ≤ 6, compressive strength ≥ 35, resistance ≤ 55, bulk density ≥ 1.54, true density ≥ 1.86

2. Semi-graphite aluminum use cathode carbon blocks

Ash content ≤ 6, compressive strength ≥ 32, resistance ≤ 40, bulk density ≥ 1.58, true density ≥ 1.92, electrolytic expansion rate ≥ 1.0

3. High graphite aluminum use cathode carbon blocks

Ash content ≤ 5, compressive strength ≥ 24, resistance ≤ 33, bulk density ≥ 1.55, true density ≥ 1.92, flexural strength ≥ 8.0

4. Dimensions: 450mm*740mm*3830mm, 515mm*580mm*3350mm; Various types and specifications of irregular carbon blocks can be processed according to customer requirements.

5. Packaging: ordinary wooden pallets or fumigated pallets, steel band packaging.

Our company mainly engages in the import and export business of carbon products, graphite carbon brick products, various self-baked and pre-baked carbon blocks for mineral furnaces, aluminum cathode carbon blocks, electrode paste, carbonized clay, cold mixing paste, and carbonizing agent, electrically calcined coal, petroleum coke, activated carbon, silicon carbide, etc.