| 摘要 |
<p>The present invention relates to a method and system for heat recovery from a gas flow (2), in which method gas is led into a boiler unit (3) comprising at least an evaporator connected to a fluid circuit for generating steam. In order to increase the efficiency of steam production by way of heat recovery from the same gas flow the method employs at least two evaporators. Gas is led in the direction of the gas flow (2) past a first evaporator (4) connected to a first fluid circuit (41) and subsequently past a second evaporator (5) connected to a second fluid circuit (51), whereby the first evaporator (4) is used to generate a high pressure steam and the second evaporator (5) is used to generate a low pressure steam. High pressure steam and low pressure steam are led to a steam ejector (7) for raising the pressure of the low pressure steam in order to generate steam having a given desired pressure, useful e.g. in an industrial process or for a steam turbine. Advantageously a third evaporator (6) is placed between the first evaporator (4) and second evaporator (5) in the direction of the gas flow (2) for generating steam of a given desired pressure, whereby steam generated by the steam ejector (7) may be brought together with steam generated by the third evaporator (6) in order to further raise efficiency.</p> |
