Acheson furnace

Fig. 5. The Acheson furnace. Courtesy of UCAR Carbon Technology Corp.

The product may then be finally heat-treated in an Acheson furnace at temperatures up to 3000°C to produce electro-graphite in which... 

D structure, healing of defects within the graphene layers occurs.63 Especially, the Acheson furnace technology is known to provide synthetic graphite materials with high crystallinity.64-66... 

Achieving the required degree of desulfurization dictated electrothermal heating. Fixed-bed electrothermal furnaces of the Acheson type were initially considered for use directly with granular coke but the test results were disappointing. The product of the Acheson furnace was not uniform in its sulfur content. Adaptation of the Acheson Process, which is a batch process, presented problems in materials handling that were considered very difficult to resolve at the 10,000 tons per year capacity determined to be the... 

In Acheson furnaces articles with very different shapes can be graphitized, making the process very versatile. The capacities of currently operated furnaces range up to net loads of 100 t or more. A typical Acheson furnace is 12 to 15 m long and 3 to 3.5 m wide and is loaded with 35 to 55 t of carbon articles. After a heating time of 3 days final... 

Castner furnaces are smaller than Acheson furnaces. Heating up and cooling down phases are significantly shorter than in the Acheson process. Also here there is a switch to continuous operation. 

After cooling, the graphitized blocks are removed from the furnace, cleaned, and inspected to determine whether property specifications have been met. Typical load-to-load cycles of an Acheson furnace are 30 days, making the process both time and capital intensive. After machining and finishing, the blocks are ready for delivery to the customer. For some materials the total manufacturing time may be as much as 5 months. 

A hard material used as an abrasive and refractory. SiC is made in an Acheson furnace carbon and silicon are packed round a core of carbon through which a large current is passed, raising the temperature to around 2000°C. (For less pure samples, coke and silica are used.)... 

Abrasive and refractory grade silicon carbide is produced industrially by the car-bothermal reduction of silica, according to the reaction in Eq. (3), from high-purity quartz sand (99.5% Si02) and petroleum coke, in electrically heated resistance furnaces (Acheson furnace) [47]. The reaction is strongly endothermic the heat of formation is 618 kj mol SiC, corresponding to 4.28 kWh kg SiC. 

Impervious graphite is manufactured by processing graphite at temperatures above 2000"C using Acheson furnaces (Section 10.2.10), evacuating the pores, and impregnating with a phenolic resin. The impregnation seals the porosity. 

Acheson Furnace. An enclosed electric resistance furnace, of the type first used by Acheson in 1891 to make silicon carbides from carbon and sand, which can attain temperatures of 2500 °C. Acicular. see morphology. 

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