METHOD FOR OPERATING A HEATING SYSTEM FOR A DRYING SECTION OF A MACHINE FOR PRODUCING OR TREATING A FIBROUS WEB, AND HEATING SYSTEM

摘要

Heating system for a machine for producing or treating a fibrous web, in particular a paper or cardboard web, and method for operating such a heating system, wherein the heating system comprises at least a first and a second heating group and the latter each comprise at least two steam-heated drying cylinders (60-66), wherein the first heating group (52) is the one which comprises the first drying cylinder (60-66), as seen in the web running direction, wherein provision is made of a separator (70) which, following flow through the drying cylinder (60-66) of the first heating group (52), separates residual steam from the condensate, and wherein provision is made of a thermocompressor (74) which sucks in the residual steam downstream of the first heating group (52), compresses said residual steam with propellant steam to the pressure level that prevails upstream of the first heating group (52), and feeds said steam back to the first heating group (52) as heating steam, wherein the propellant steam is at a pressure which is not greater than the pressure of the main heating steam of the heating system.