Condensate collection systems reuse

The interaction of a steam reboiler with its condensate collection system can be very simple or very complex. Simple in the sense that the plant operators are satisfied to drain the steam condensate to the sewer from the channel head of the steam reboiler or feed preheater. Complex if the operators are trying to route the condensate back to the steam generation (boiler house) for recovery and reuse. 

Fossil Fuel-Fired Plants. In modem, fossil fuel-fired power plants, the Rankine cycle typically operates as a closed loop. In describing the steam—water cycle of a modem Rankine cycle plant, it is easiest to start with the condensate system (see Fig. 1). Condensate is the water that remains after the steam employed by the plant s steam turbines exhausts into the plant s condenser, where it is collected for reuse in the cycle. Many modem power plants employ a series of heat exchangers to boost efficiency. As a first step, the condensate is heated in a series of heat exchangers, usually sheU-and-tube heat exchangers, by steam extracted from strategic locations on the plant s steam turbines (see HeaT-EXCHANGETECHNOLOGy). 

Within any particular facility, steam is expected to be delivered to various points of use safely and at controlled temperatures and pressures through relatively long-lasting distribution networks. Where the steam is not excessively contaminated or directly consumed in a process as live steam, it should be condensed, collected, and returned to the boiler for reuse. Thus, the post-boiler section of a boiler plant essentially relates to the systems concerned with steam distribution and condensate return (CR). 

Steam is used in the largest quantities in the evaporation of caustic and, sometimes, brine. A system for the collection and reuse of steam condensate goes hand-in-hand with steam supply. In this chapter, we also consider the use of steam as a source of mechanical power. This is of growing importance as more of the industry adopts cogeneration. 

In a mercury diffusion pump, the mercury is heated to the point of vaporization. This vapor travels up into the condenser area where it is ejected at supersonic speeds from little holes. The vapor knocks any wandering gas molecules down toward the mechanical pump outlet which can then expel them from the system. The vapor later condenses and collects in the heating pot for reuse. 

Disc rotation can be automatically triggered from the GPC upon injection or at some preset delay so sample collection is virtually unattended. The speed of rotation of the disc is adjusted to match the time of the evolution of the sample from the chromatograph. At a speed of 10 deg/min, 36 min of sample collection can take place on each disc. The Ge discs are easily cleaned and can be reused. After collection, the disc is removed and placed in a 3X beam condenser within the PTIK optics cabinet. The beam condenser is designed to provide an optical match between the FTIR beam size, which is mm, and the size of the deposited sample, 3 mm. Once seated on the platform in the beam condenser, the disc is rotated beneath the IR beam and spectra of individual samples collected. If the FTIR system has the capability of continually collecting spectra, then the spectra of the polymer deposit can be displayed continuously, thus generating an IR chromatogram. If this software is not available, the spectra may be individually collected and displayed by scanning the disc from point to point. 

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