Integrating production with steam

In the area of simplification of heat transport, chemical compatibility among heat transport working fluids (e g., Na and Ar-N Pb-Bi and steam or CO2) is introduced so that an intermediate circuit is eliminated and integral (in-vessel) steam generators or heat exchangers can be employed, e.g., like in the BN GT-300 (17), SSTAR (24), STAR-LM (25), and STAR-H2 (29). Natural circulation of the primary coolant at full power is used for many concepts. In the lead-bismuth cooled ENHS (19), a gas lift pump option is considered as an alternative to either natural circulation or mechanical or electromagnetic pumps. Similar approach, coupled with direct contact production of steam is employed in a lead-bismuth cooled PBWFR (23). 

A much improved ORC-process can be obtained with heat recovery steam (HR-steam) from the TMP-steam reboilers. An integrated mill with a TMP-plant combined with a paper machine is taken here as an example. Paper grade is newsprint with a basis weight of 40 g absolute dry web/m. With a machine speed of 1700 m/min and a sheet width of 10 m the production of paper is 12.3 kg/s air-dry paper with 92 % dry solids. The paper... 

Conventional heat recovery from paper machine exhaust air streams can be designed optimally with respect to the climate at the mill location and the type of drying process involved. Different heat pump types can be applied, for example absorption heat transformers, to elevate the stream temperatures above the temperature of the excess heat. In an integrated mill with impingement drying the eventual excess low-pressure steam from the TMP-heat recovery, before or after the reboilers, can be utilised in an organic Rankine cycle for production of electrical power. The next step is to study the design and economic aspects of different types of ORC-plants. 

III-13. As a consequence of the steam line break, the integrity of the steam generator tubes, which depends on the pressure difference between the primary and the secondary sides, needs to be assessed. If the structural integrity of the steam generator tube cannot be assured, the amount of primary water that could enter the secondary side needs to be estimated. After the shutdown of the reactor, the radionuclide content of the leaking water may increase with time owing to the effects of fission product spiking, as discussed in Annex II. 

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