Chemical recovery boiler

A chemical recovery boiler, the boiler comprising:

• a furnace for recovery of chemicals and thermal energy generated in a burning process and comprising:
• a front wall,
• a back wall, the back wall comprising a nose arch, and
• at least one superheater arranged in an upper part of the furnace, and
• a screen pipe system comprising:
• an obliquely arranged screen pipe section positioned before/under the at least one superheater in the furnace, the obliquely arranged screen pipe section comprising screen pipes ascending either:
• (i) from the front wall to the back wall, and arranged to turn back in a turn from the back wall and extend obliquely upwards from the back wall, or
• (ii) from the back wall to the front wall, and arranged to turn back in a turn from the front wall and extend obliquely upwards from the front wall, and
• a vertically arranged screen pipe section extending from the obliquely arranged screen pipe section, wherein screen pipes of the vertically arranged screen pipe section extend parallel with the at least one superheater in the upper part of the furnace,
• wherein the obliquely arranged screen pipe section is positioned to penetrate through the either the front wall or the back wall, such that the turn, where the obliquely arranged screen pipe section turns back into the furnace, is placed outside of the furnace.