Improvements in paper machine performance require a high efficiency steam and condensate removal system. An appropriate design allows, also, to reduce the energy consumption and cut the operating costs.
The motive steam, under pressure, enters the thermo-compressor and flows through the nozzle. The motive and the blow through steam are mixed in the thermo-compressor body. Into the diffuser the velocity head of the steam is converted to a static head so that proper discharge pressure can be obtained.
The 1st separator tank receives the two phase flow, condensate and blow through steam, from the Yankee Dryer. The blow through steam is fed to the thermo-compressor and the condensate flows from the bottom of the separator to the boiler.
A 2nd separator is also installed to collect the condensate coming from the steam coil of the Hall Heating and Ventilation System. The condensate is pumped from the 2nd separator to the boiler directly.
The steam pressure in the Yankee Dryer is controlled with a pressure regulator that operates with the thermo-compressor opening and the make up steam control valve connected in split-range. The amount of blow through steam is controlled by a Vortex through dedicated control valves. The thermo-compressor is installed in parallel with make up valve that provides the additional steam required.
A level transmitter controls the condensate level into the separator through a control valve, and an on-off (operate in case of overflow and send the condensate to the hot well).
|TT Milltech S&C||Unit||Value|
|Boiler steam pressure available (min. at thermo-compressor)||bar(g)||18 (max 20)|
|Yankee steam max pressure||bar(g)||10|
|Yankee steam operating pressure||bar(g)||up to 9,2|