According to this invention, the as-shipped anode or needle coke particles are initially screened into two fractions, with a coarse-grain fraction containing particles larger than 5 mm. The coarse grain fraction is then online-fed into a mill having stronger milling-paddles and yielding grains of 200 μm to 3 mm. In parallel, a fine-grain fraction is fed into a mill designed for finer grains and providing particles of 25 μm to 300 μm size. The two fractions are then joined once more and the resulting powder contains coke particles with a Gaussian particle size distribution between 25 μm and 3 mm.
 The power is pre-heated to 100-125° C. in a rotating-drum heating unit and then mixed at 150 to 160° C. in an intensive mixer, such as an Eirich mixer (Maschinenfabrik Gustav Eirich GmbH & Co KG, Hardheim, Germany), together with 15% (w/w) binder pitch.
 In one further embodiment, up to 5% (w/w) graphite dust from machining of graphite electrodes and green scrap from other operations may be added to the intensive mixer as well.
 Other ingredients that may be incorporated into the blend at low levels include carbon nanofibers or carbon fibers to provide additional mechanical strength or to adjust the CTE (coefficient of thermal expansion) of the final electrode as well as oils or other lubricants to facilitate extrusion of the blend.
 The resulting so-called green mixture is then forwarded to a press or extrusion unit where the so-called green electrodes are shaped to their final format.
 The green electrode is then baked at a temperature of between approx. 700° C. and approx. 1100° C., more preferably between about 800° C. and about 1000° C., to carbonize the pitch binder to solid coke, to give the electrode permanency of form, high mechanical strength, good thermal conductivity, and comparatively low electrical resistance. The baking step is carried out in the relative absence of air at a heating rate of about 1 K to about 5 K per hour to the final temperature. After baking, the electrode may be impregnated one or more times with coal tar or petroleum pitch, or other types of pitches known in the industry, to deposit additional pitch coke in any open pores of the electrode. Each impregnation is then followed by an additional baking step.
 After baking, the electrode—referred to at this stage as a carbonized electrode—is then graphitized by heat treatment for a time sufficient to cause the carbon atoms in the calcined coke and pitch coke binder to transform from a poorly ordered state into the crystalline structure of graphite. If anode coke is used as the starting material, the graphitization is carried out at a final temperature between 2100° C. to 2700° C., more preferably between 2200° C. to 2500° C. Because of the purity of the anode coke, the comparably low graphitization temperatures are sufficient to reach the required final electrode ash contents. If needle coke is used as the raw material, graphitization is performed at a temperature of between about 2700° C. and about 3200° C. At these high-temperatures, all elements other than carbon are volatilized and escape as vapors. The time required for maintenance at the graphitization temperature is no more than about 12 hours, preferably about 30 min to about 3 hours. Graphitization can be performed in Acheson furnaces or in lengthwise graphitization (LWG) furnaces, the latter can also be operated in a continuous mode. After graphitization is completed, the finished electrode can be cut to size and then machined or otherwise formed into its final configuration.
 A comparative conventional graphite electrode was manufactured by using needle coke with particles up to about 25 millimeters (mm) in average diameter. The crushed, sized and milled coke was mixed with 15% (w/w) coal-tar pitch in a Z-arm kneader. The resulting green mixture was subsequently processed into an graphite electrode as described above.
 The present invention offers numerous advantages over the art. It provides electrodes with required mechanical strength without the need for any sieving or blending operational steps. Due to the shortened manufacturing sequence, the quality of the final graphite electrode can be kept at a very defined level with fewer rejections and the same production line can have more throughput than conventional lines. Electrode type GEanode coke GEneedle coke GEconventional Bulk Density (g/cm3) 1.76 1.78 1.73 Open Porosity (%) 22 14 17 Specific electrical (μOhm m) 10 4 6 resistivity Flexural strength (N/mm2) 20 26 14 Iron content (%) 0.07 0.25 0.2
 The above description is intended to enable the person skilled in the art to practice the invention. It is not intended to detail all of the possible variations and modifications that will become apparent to the skilled worker upon reading the description. It is intended, however, that all such modifications and variations be included within the scope of the invention that is defined by the following claims. The claims are intended to cover the indicated elements and steps in any arrangement or sequence that is effective to meet the objectives intended for the invention, unless the context specifically indicates the contrary.