Coke oven roof repair or replacement

A method of repairing or replacing a roof of a coke oven battery in operation, said coke oven battery comprising a number of parallel coking chambers separated by heating walls and delimited on top by a ceiling, itself covered by a roof, the roof comprising for each coking chamber a first plurality of charging holes or gas transfer holes above said coking chamber, a second plurality of inspection holes above said separating heating walls, one or two base rings of an ascension pipe connected to one or two gas collecting mains and rail sleepers configured for supporting rails for a coke charging car or charging gas transfer car, the method including the following steps of:

• I.a) if required, taking out of operation at least one coking chamber by discharging any hot coke contained therein and disconnecting said base ring(s) from the gas collecting main(s),
• I.b) removing any damage roof parts above said at least one coking chamber and adjacent heating walls, including one or more charging holes or gas transfer holes, inspection holes, base ring and rail sleepers, optionally providing temporary support for the rails above the at least one coking chamber and adjacent heating walls,
• I.c) providing a set of construction modules, each construction module comprising a set of elements:
• a first plurality of charging hole or gas transfer hole modules, each comprising one or more refractory precast support blocks for charging hole or gas transfer hole and a metal charging or gas transfer hole frame with a metal lid, a second plurality of inspection hole modules, each comprising a refractory precast support block for inspection hole and a metal inspection hole frame with a metal lid, one or two base ring modules, each comprising one or more refractory precast support blocks for base ring and a metal base ring, rail sleeper modules, each comprising one or more refractory precast support blocks for sleeper and a metal sleeper, and a finishing module comprising a third plurality of liner slabs, mortar and refractory castable filler material, wherein said refractory precast support blocks are made of low expansion refractory material,
• I.d) placing the first plurality of charging hole or gas transfer hole modules, and/or the second plurality of inspection hole modules, and/or the base ring module(s) and/or the rail sleeper modules at predetermined respective locations within the space of the roof, and if necessary connecting adjacent refractory precast blocks with the mortar;
• I.e) partially filling a void space within the roof left after steps I.b) and I.d) with liner slabs, and filling the remainder of the void space within the roof by pouring and/or casting the refractory castable material;
• I.f) if previously disconnected, connecting the base ring(s) with the gas collecting main(s) and taking into operation the at least one coking chamber with the repaired or replaced roof, attaching the rails to the sleepers and, if previously installed, removing the temporary support for the rails provided in step I.b), and
• I.g) repeating steps I.a) to I.f) for a further at least one coking chamber, as necessary or desired,
• wherein the method further includes the following step:
• I.d1) waiting for the modules placed in step I.d) and/or the liner slabs placed in step I.e) to exceed a predetermined temperature threshold, thereby enabling said modules and/or liner slabs to undergo thermal expansion, before pouring the refractory castable material;
• and wherein the repairing or replacing is performed while the roof of the coking chamber is exposed to a temperature of at least 200° C.