A carbon electrode used for an arc discharge for manufacturing a quartz glass crucible, wherein at least one of a concave pattern and a convex pattern is formed on a surface of the carbon electrode in at least a range of 50 mm to 130 mm in a longitudinal direction of the carbon electrode from an end portion where the arc discharge takes place. Consequently, a carbon electrode that can suppress agglomeration of silica fume on the carbon electrode while manufacturing a quartz glass crucible is provided.

A method produces a molded part from carbon containing carbon fibers in an amount of less than 20% by weight. The method includes comminuting waste parts or scrap parts formed from a carbon fiber-reinforced synthetic material, a carbon fiber reinforced carbon or a carbon fiber reinforced concrete. A mixture is produced from the comminuted product, a binder such as pitch, a carbon material such as coke and optionally one or more additives, wherein the mixture contains less than 20% by weight of fibers. The mixture is molded into a molded part and the molded part is carbonized. Optionally, the molded carbonized part is impregnated with an impregnating agent. Finally and optionally, the molded carbonized part or the molded part impregnated part is graphitized.

A method produces a molded part from carbon containing carbon fibers in an amount of less than 20% by weight. The method includes comminuting waste parts or scrap parts formed from a carbon fiber-reinforced synthetic material, a carbon fiber reinforced carbon or a carbon fiber reinforced concrete. A mixture is produced from the comminuted product, a binder such as pitch, a carbon material such as coke and optionally one or more additives, wherein the mixture contains less than 20% by weight of fibers. The mixture is molded into a molded part and the molded part is carbonized. Optionally, the molded carbonized part is impregnated with an impregnating agent. Finally and optionally, the molded carbonized part or the molded part impregnated part is graphitized.

A graphite electrode includes a pole having a socket in an internal screw shape at an end portion, and a nipple in an external screw shape that can be fastened to the socket, wherein a value obtained by subtracting an effective diameter on a small diameter end side of the nipple from an effective diameter on a small diameter end side of the socket is 0.05 to 0.7 mm, and a value obtained by subtracting a taper angle of the socket from a taper angle of the nipple is ?2 minutes to ?3 minutes 30 seconds.

A graphite electrode includes a pole having a socket in an internal screw shape at an end portion, and a nipple in an external screw shape that can be fastened to the socket, wherein a value obtained by subtracting an effective diameter on a small diameter end side of the nipple from an effective diameter on a small diameter end side of the socket is 0.05 to 0.7 mm, and a value obtained by subtracting a taper angle of the socket from a taper angle of the nipple is ?2 minutes to ?3 minutes 30 seconds.

A method for the production of polygranular graphite bodies including the step of provisioning a mixture including a high-temperature treated anthracite having a high vitrinite content and a petroleum-based needle coke and/or a pitch-based needle coke, and provisioning at least one binder coke precursor. The method also includes the steps of forming a green body from the mixture from the provisioning step, and carbonizing and graphitizing the green body.

A method for the production of polygranular graphite bodies including the step of provisioning a mixture including a high-temperature treated anthracite having a high vitrinite content and a petroleum-based needle coke and/or a pitch-based needle coke, and provisioning at least one binder coke precursor. The method also includes the steps of forming a green body from the mixture from the provisioning step, and carbonizing and graphitizing the green body.

A pitch product having a petroleum-derived distillation residue and a coal tar-derived distillation residue, said pitch product characterized by a concentration of at least 84% asphaltenes (SARA). Further, the present invention is directed to a pitch binder including said pitch product useable in manufacturing of graphite electrodes for electric arc furnaces, and carbon anodes and Soederberg paste for aluminum production. The present invention is further directed also to a graphite electrode having said pitch binder, as well as to a carbon anode comprising said pitch binder. The present invention also provides a process for producing a pitch product including a petroleum-derived distillation residue and a coal tar-derived distillation residue, said process including a petroleum vacuum distillation process step for obtaining said petroleum-derived distillation residue, and a process for manufacturing a graphite electrode or a carbon anode including said process for producing a pitch product.

A pitch product having a petroleum-derived distillation residue and a coal tar-derived distillation residue, said pitch product characterized by a concentration of at least 84% asphaltenes (SARA). Further, the present invention is directed to a pitch binder including said pitch product useable in manufacturing of graphite electrodes for electric arc furnaces, and carbon anodes and Soederberg paste for aluminum production. The present invention is further directed also to a graphite electrode having said pitch binder, as well as to a carbon anode comprising said pitch binder. The present invention also provides a process for producing a pitch product including a petroleum-derived distillation residue and a coal tar-derived distillation residue, said process including a petroleum vacuum distillation process step for obtaining said petroleum-derived distillation residue, and a process for manufacturing a graphite electrode or a carbon anode including said process for producing a pitch product.

An embodiment disclosed herein includes a monolithic graphite electrode. The electrode has a main body having a length of more than 3050 mm. Another embodiment disclosed herein includes an electrode column comprising a plurality of monolithic graphite electrodes. The column has a length of more than 3050 mm of electrode per joint. A further embodiment discussed herein is the practice of increasing the length of the electrode to minimize the occurrence of an electrode joint in the electrode column for a given length. This practice will improve efficiencies for both electrode manufacturers as well as electric arc furnace operators.