Reducing gas injection system

A reducing gas injection system for a blast furnace comprising a blast furnace wall, wherein the reducing gas injection system comprises

• a reducing gas distribution pipe,
• one or more injectors mounted to the blast furnace wall at a shaft level,
• wherein the reducing gas distribution pipe is attached to the blast furnace wall or a supporting structure thereof,
• wherein said injector(s) comprise(s) a nozzle body with a peripheral wall extending along a longitudinal axis from a front portion, with at least one injection hole, to an opposite rear portion with an inlet port, wherein the nozzle body includes an inner gas channel for guiding reducing gas from said inlet port to said injection holes(s);
• wherein said nozzle body is mounted through an aperture in said blast furnace wall in such a way that the front portion with the injection hole(s) is located on an inner side of said blast furnace, whereas said rear portion with the inlet port is outside of said blast furnace wall,
• wherein said nozzle body comprises a peripheral mounting portion configured for connecting said injector in a gas tight manner to said aperture in said blast furnace wall,
• wherein the inlet port is in fluidic connection with the reducing gas distribution pipe by means of an injector stock, said injector stock comprising a feeding pipe connected to the reducing gas distribution pipe, an elbow connected to said feeding pipe and an injector pipe connected to said elbow, said injector pipe being flange mounted in a gas tight manner to the inlet port of the injector and said injector pipe and/or an outlet of the elbow comprising at least one cardan compensation joint.