# 3.3 Temperature profiles, inspection zones (optimisation of an arrangement of gauges)

One of essential lacks of domestic practice of rectification, and also its designing, the insufficient attention to questions of observability and controllability of process is. Research of ways of operative indirect measurements of key parametres of process should become a necessary stage of increase of efficiency of operating process.

Temperature the rectification column profile is the major index of a duty of a column, easily accessible to the control.

The inspection zone (or a plate) is understood as such plate on which the greatest sensitivity of change of temperature to change of any entrance parametre is observed. Generally position of a control plate in a column is not constant size, its site depends on parametre and perturbation size. However within normal operation of a column displacement it is not so significant, that allows to define area of plates, the most sensitive to perturbation by carrying out of a minimum quantity of experiments on mathematical model of process. Practically any perturbation of a separation process can be transformed to equivalent change of selection from potential. Therefore a variation of selections round basic value (for example, design) most easier to define area of the maximum changes of a profile of temperatures. Any plate can serve in this area as a control plate. This simple principle is taken by authors as a principle a technique of definition of inspection zones applied in yielded work. The example of application of offered methodology of optimisation of an arrangement of gauges is resulted more low.

In drawings 3.3 - 3.5 temperature profiles of work of columns are presented at various selections (letter N on the specified graphs designates numbers of plates). In drawings 3.6 and 3.7 examples of results of processing, a drawing of deviations temperature a profile of columns К-404 and К-101 from basic are presented at various selections. We will consider more in detail. If for a basic mode on selection to take over design, corresponding to selection less potential (for example,

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D/DonT = 0.98) the area of the most sensitive plates on temperature in this case is between 30 and 45 plates in exhaustive shell of column according to drawing 3.6. As a control plate can serve 35. If for the basic mode to take over a mode corresponding to selection more potential, area of the most sensitive plates on temperature moves in fortifying shell of column and settles down between 83 and 93 plates and as the control 90th plate can serve.

For the basic mode corresponding to selection, equal potential, the area of the most sensitive plates is as in settling (45 plate), and in fortifying (65-80 plates) column sections. For column К-404 the mode of potential selection is primary by all criteria, and for this column control plates should be defined at the basic selection equal to the potential.

In drawing 3.8 influence of hydrodynamics on areas of control plates is presented. From drawing it is visible, that for valving plates of change of temperature of inspection zones are expressed much more strongly (approximately in 4 times), than for the screen. It means, that the wiper type considerably influences observability of object. This moment is noted in the considered publications on rectification.

From data of subsection and graphs in drawings 3 it is possible to draw a conclusion, that observability of process of rectification can be improved essentially, if by offered methodology of mathematical experiments on process models

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To define localisation of inspection zones temperature a profile. Application of the developed technique of experiments on models for the purpose of mode optimisation has allowed the author during works under the contract №2222 between Open Society "СвНИИНП" and Open Society «Achinsk NPZ» to yield recommendations [153] on decrease in reflux-to-product ratioes on GFU Open Society "Achinsk NPZ", equivalent to decrease in power inputs on 35-40 %.

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Plate number

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SS SS 70 72

74 7 AND 70