Rectification test plant

Figure 6-6. Picture of rectification test plant DN 200, shown as diagram in Fig. 6-5...

The pyrolysis products, together with the fluidizing gas (i.e. the noncondensable pyrolysis gases), leave the reactor via a cyclone, where dry carbon soot and filler materials are precipitated. A cooling system and an electrostatic precipitator condense the liquid fraction of the pyrolysis products. The waste heat is used to heat up the fluidizing gas. A stream of pyrolysis products is branched off the main product cycle and refined in the rectification unit described for the smaller test plant. 

Figure 6-5. Diagram of test plant for investigation of packings used for vacuum rectification. Column diameter ds = 150 and 220 mm, packed bed height H = 1.0-1.7m... 

It is advisable to start a constant-pressure filtration test, like a comparable plant operation, at a low pressure, and smoothly increase the pressure to the desired operating level. In such cases, time and filtrate-quantity data shoulci not be taken until the constant operating pressure is reahzed. The value of r calculated from the extrapolated intercept then reflec ts the resistance of both the filter medium and that part of the cake deposited during the pressure-buildup period. When only the total mass of diy cake is measured for the tot cycle time, as is usually true in vacuum leaf tests, at least three runs of different lengths should be made to permit a rehable plot of 0/V against W. If rectification of the resulting three points is dubious, additional runs should be made. 

Rectification accounts for systematic measurement error. During rectification, measurements that are systematically in error are identified and discarded. Rectification can be done either cyclically or simultaneously with reconciliation, and either intuitively or algorithmically. Simple methods such as data validation and complicated methods using various statistical tests can be used to identify the presence of large systematic (gross) errors in the measurements. Coupled with successive elimination and addition, the measurements with the errors can be identified and discarded. No method is completely reliable. Plant-performance analysts must recognize that rectification is approximate, at best. Frequently, systematic errors go unnoticed, and some bias is likely in the adjusted measurements. 

Further pre-operational testing was considerably impeded and delayed fi om the second half of 1985 until late 1986 by special unexpected events described later. Rectification of these events made it necessary to repeat various testing steps already carried out. Nevertheless, it was possible to inert the primary cell areas in December 1985. The 95% completion already mentioned included approximately 3040 single system and approximately 200 interconnected system tests. Thus in spring 1986, the plant was ready to accept the breeder and fuel... 

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