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INTRODUCTION

Now, in connection with a forthcoming Russia's accession to the World Trade Organization, for the domestic enterprises performance of requirements of standards of series ISO 9000 on maintenance maximum «identifiabilities, observabilities and controllability» productions is rather actual.

Maintenance of these requirements concerning process of rectification of oil is rather a challenge as except dynamism (presence of permanent and essential time histories), complexity and distribution of parametres in space and time for this process characteristicly application of a special kind of raw materials - the oil, which in itself is difficult and dynamical physical and chemical system. Despite a significant amount of works on control improvement over process, there is an actual problem of incomplete observability and, accordingly, incomplete controllability of process of primary division of oil. On top levels of management factory oil refining widely applies now modern systems of technical and economic modelling and optimisation (PIMS, RPMS, etc.) which on the basis of economic criteria, marketing conditions and the average reading on quality of manufactured petromixes give out optimum tasks for level of separate installations. However on installations of rectification of oil actual selections of fractions, as a rule, are considerably wedged from optimum tasks. Principal causes of it consists in the following:

• distinctions of planned - and actual quality of raw materials; absence of methods and the algorithms allowing operatively to receive an authentic pattern of division of oil and by that to provide the full and unconditional control over process.

The economic sense of a problem of observability of process of primary division of oil consists available on installations of rectification of a superfluous stock on quality, that is unprofitable redistribution of fractions in favour of invaluable products. This stock depends on degree of perfection of the equipment and makes on various installations from 1-2 to 6-8 % May. In recalculation on oil. Similar

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The stock called sometimes "dynamic", inevitably arises in the conditions of incomplete observability as a result of the most various technological manipulations on process control for indemnification operators not observed and uncontrollable them of perturbation. Therefore the economic target of the present research consists in revealing and the instructions of paths of decrease in this stock on quality, and gains in yield of main products by approach of actual selections to optimum values.

The basic tool for representation of the information on process and realisation of operating influences are the distributed automatic control systems of technological processes (ASUTP), representing a complex technical and programmno and algorithmic means. The total of parametres which are going and deduced on monitors of workplaces of operators-technologists, reaches several thousand. The quantity of the information on process in the form of separate measurements is so great, that operative and their correct interpretation in a mode of real time without use of special algorithms is practically excluded. The last, apparently from table 1 data, is the basic moment worsening quality of management.

Table 1 - Degree of an inaccuracy of the decision of the operator depending on time released on the decision

Time which has been released on the decision, minute 1 5 30 120 Share of errors, % 99 90 9 1 Apparently from table data, simple informing, let even operative, does not yield guarantees of the correct decision and, on the contrary, glut of the operator by the information in the conditions of deficiency of time result ins so-called "information" illness.

For this reason it is necessary to provide correct interpretation of the key information and data with representation of results in a kind of estimation of a condition of process as much as possible integrated and adapted for perception.

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Any interpretation demands a conceptual basis, i.e. model of interaction of the planned purpose, observable object and environment (sources of perturbation), i.e. assumes the obligatory pre-award decision of a problem tseleukazanija. Besides, as local process "is built in" the general schema of petroleum refineries (NPZ), ways of interaction of local technological process with technical and economic НПЗ environment surrounding it, i.e. a correct way of decomposition of global criterion of optimisation on the local should be defined. This question as having special methodological importance should be evolved in the decision of a separate problem. Therefore the choice of the criterion allowing operatively to estimate degree of an optimality of a mode of division of oil on products of set assortment should become the major research problem.

Oil as raw materials of process and a source of the basic perturbation of process is the independent and extremely difficult dynamic system which supervision of properties in a real time mode is separate and rather uneasy problem. In it the main difference of process of rectification of oil from rektifi-katsii the limited number of precisely identified components. The same values of integrated parametres of quality (such as density, temperature for-styvanija viscosity, etc.) which serve now as the main criteria the management purposes, can be received at various selections and superpositions of adjacent fractions, i.e. at different conditions of process. Thus, the decision of the general problem of the control of process of primary distillation has as though «the doubled complexity» in comparison with rectification of the limited number of components and accordingly includes two groups of problem problems:

Operative estimation (identification) of properties of oil;

Operative estimation (identification) of a condition of process.

The problem of incomplete observability and controllability of process of rectification of oil, being the basic hardle for economically effective intensification and oil refining optimisation, makes a subject of the present research.

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The work purpose - increase of accuracy of performance of optimum tasks of top level of management (systems PIMS. RPMS, etc.) by a choice and a substantiation of ways of correct decomposition of global criterion of optimisation of oil refining on the local. Creation on the basis of the chosen criteria of a complex of methodical and algorithmic means, for optimum control of technological process of rectification of oil.

The primary goals of research was the following:

Definition of typical properties of static characteristics of rectification columns (structural and parametrical identification of typical models of a statics of process of rectification in columns of various type) and the analysis of features of a nonlinear problem of minimisation of power inputs of rectification for the purpose of search of the most rational ways of its decision.

Working out of technical and economic criterion (the management concept) for rectification of the oil, the positioned modes of rectification columns considering typical property and features of an optimising problem of minimisation of power inputs of rectification.

Working out of algorithm of optimum control by process of primary division of oil with use of the chosen local criteria of the optimisation providing correct unequivocal linking to global optimisation of all schema of petroleum refining at factory.

Working out of ways of operative identification of key properties of oil.

Working out of algorithms of an estimation (supervision) of target parametres of process inaccessible to direct measurements, including actual temperatures of partition and superpositions of adjacent fractions, selections from potential, etc.

The basic results of the made work Scientific novelty:

1. For the first time the criterion of an optimality of process of rectification of oil on the basis of the connected pair key parametres - «partition temperatures» and "superpositions" of the adjacent fractions is offered, allowing to keep set (optimal -

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noe) distribution of close-cut fractions in products of division of oil invariantno to fluctuations of quality of raw materials.

On the basis of the positioned features of typical number-density distributions of manufactured petromixes the identification models, allowing to estimate fractional composition of manufactured petromixes in a real time mode for the first time are offered.

It is offered dekompozirovannaja model of quality of the oil, allowing operatively to predict yields of main products of the set assortment.

On protection are taken out:

Methods and means of operative identification of the basic properties of oil and mineral oil;

Model of integrated properties of the oil, allowing operatively to predict yields of main products of the set assortment;

Method and criterion of an estimation of a local optimality of process of rectification of oil;

Algorithms and programmno a software for optimum control of rectification of oil on the basis of the chosen criterion, and for the determined and statistical modelling of processes;

Technique of modelling and optimisation of the positioned process conditions of rectification.

The personal contribution of the author

Working out of criteria and algorithms of optimisation (mathematical and the software), working out and introduction of a programmno-software for ASUTP on the basis of controllers "Remikont", working out of a method and lips

rojstva for an estimation of composition of a multicomponent mixture, working out and introduction of a programmno-mathematical complex for construction of the integrated pattern of division on the atmospheric block. Participation (working out of separate modules) in working out of a package of the determined modelling «POLIFUN». Problem statement, a management, participation in working out and a choice of settlement formulas for a package «PREDICT ASSAY».

Economic benefit.

Application of the technique of optimisation study developed by the author on-zvolilo to give out and realise recommendations about optimisation of a mode of rectification of oil on installation ГК-3 Open Society "АНХК", namely to reduce losses of the most valuable products with auxiliary (black oil) on 41 %. Thus expenses for optimisation (inspection, calculations have, etc. made about 700 thousand roubles while the alternative variant - reconstruction was estimated by Open Society "АНХК" management in 1,5-2 million dollars). For installation GFU Open Societies «Achinsk NPZ» are yielded the recommendation about improvement of systems of the regulation, allowing to reduce power inputs on 35 %.

The offered model of properties of oil and the technique of the forecast of yields of products developed on its base at rectification of oil taking into account assortment requirements, and also program module PREDICT ASSAY realising it allow to set optimum temperatures of partition of adjacent fractions and operatively to estimate potentials of products. Technique application allows to increase efficiency in comparison with technique VNIINP applied now approximately in 400 times.

Developed on the basis of identification model of oil a hardware-software complex "ITK", implanted on installation АВТ-11 Open Society «NK NPZ», allows to estimate key parametre of quality of oil (fractional composition).

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A source: Kuznetsov Viktor Georgievich. ALGORITHMIZATION AND OPTIMIZATION OF THE TECHNOLOGICAL PROCESS OF RECTIFICATION OF OIL. DISSERTATION for the degree of candidate of technical sciences. 05.13.06 - Automation and management of technological processes and production (industry). Samara-2005. 2005

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