Adaptive control of drilling by identifying parameters of object model under nonstationarity conditions

Purpose. The research is intended to investigate and synthesize adaptive control over drilling by identifying parameters of an object model under non-stationarity conditions. Methods. Under conditions of rapidly changing borehole drilling indices, a two-level adaptive control strategy is applied, combining investigation of drilling and its control. The structure of the control system includes an additional block of forming the model on the basis of data on indirect features. Findings. The research develops a method for seeking the extremum developed for the object whose dynamics is described by a first-order linear differential equation. The method allows to determine the value of the output signal by evaluating the initial phase of the transient process caused by the changed input signal for a set step. Originality. The suggested algorithm of noise-free identification makes it possible to assess the factor of the control object transfer under the action of random disturbances. The data obtained is used to adjust the gain factor of the controller in the closed loop automatic control system of drilling. Practical implications. The suggested structure and algorithm of drilling control allow enhancing drilling efficiency by ensuring relevant mechanical drilling rates through defining corresponding rotation speeds and axial loads of a drilling tool.Мета. Метою роботи є дослідження і синтез адаптивного керування процесом буріння в умовах нестаціонарності на основі ідентифікації параметрів моделі об’єкта. Методика. В умовах показників процесу буріння свердловин, що досить швидко змінюються, використана стратегія дворівневого адаптивного управління, яка полягає в одночасному дослідженні процесу буріння й керуванні даним процесом. При цьому в структуру системи керування додатково включено блок формування моделі на основі інформації про непрямі ознаки. Результати. Розглянуто метод пошуку екстремуму стосовно об’єкта, динаміка якого описується лінійним диференціальним рівнянням першого порядку. Метод дозволяє по початковій ділянці перехідного процесу в об’єкті, викликаного зміною вхідного сигналу на заданий крок, визначити стале значення вихідного сигналу об’єкта. Наукова новизна. Пропонований алгоритм перешкодозахищеної ідентифікації дозволяє оцінити величину коефіцієнта передачі об’єкта керування в умовах дії випадкових перешкод. Отримана інформація використовується для ефективного налаштування коефіцієнта посилення регулятора у замкнутій системі автоматичного керування технологічним процесом буріння. Практична значимість. Запропоновані структура і алгоритм керування процесом буріння, що дозволять підвищити ефективність процесу буріння свердловин, забезпечивши оптимальну механічну швидкість буріння шляхом визначення відповідних значень частоти обертів і осьового навантаження породоруйнуючого інструменту.Цель. Целью работы является исследование и синтез адаптивного управления процессом бурения в условиях нестационарности на основе идентификации параметров модели объекта. Методика. В условиях достаточно быстро изменяющихся показателей процесса бурения скважин использована стратегия двухуровневого адаптивного управления, которая заключается в одновременном исследовании процесса бурения и управлении данным процессом. При этом в структуру системы управления дополнительно включен блок формирования модели на основе информации о косвенных признаках. Результаты. Рассмотрен метод поиска экстремума применительно к объекту, динамика которого описывается линейным дифференциальным уравнением первого порядка. Метод позволяет по начальному участку переходного процесса в объекте, вызванного изменением входного сигнала на заданный шаг, определить установившееся значение выходного сигнала объекта. Научная новизна. Предлагаемый алгоритм помехозащищенной идентификации позволяет оценить величину коэффициента передачи объекта управления в условиях действия случайных помех. Полученная информация используется для эффективной подстройки коэффициента усиления регулятора в замкнутой системе автоматического управления технологическим процессом бурения. Практическая значимость. Предлагаемая структура и алгоритм управления процессом бурения позволяют усилить его эффективность путем обеспечения необходимой скорости механического бурения, определения соответствующих скоростей вращения и осевых нагрузок на бурильный инструмент.The authors express their sincere gratitude to Kryvyi Rih National University for support in conducting research

Improving efficiency of iron ore thickening and deslurrying

Purpose. The research is aimed at improving efficiency of thickening and deslurrying products of iron ore concentration and quality of magnetite concentrate by means of dynamic effects of controlled high-energy ultrasound and the magnetic field impacting ore slurry solids in the output product of the deslimer. Methodology. The research is based on the systemic approach used to define regularities of high-energy ultrasound propagation in heterogeneous media, develop mathematical and simulating models of these processes and methods of improving thickening and deslurrying of iron ore concentrate by combining impacts of the ultrasonic and magnetic fields

Mineralogical analysis of iron ore using ultrasonic wave propagation parameters

Availability, relative simplicity and low cost, combined with ever-increasing capabilities, have led to a significant increase in the use of ultrasonic measurements of mining process variables in recent times. The scope of application varies from the study of the characteristics of raw materials and products of its processing to the operational assessment of the current parameters characterising the state of the process equipment. The purpose of this study is to develop methods for obtaining information about the characteristics of mineral raw materials as a result of ultrasonic logging of wells in a rock mass. The proposed approach makes it possible to improve the quality of information support for the management of technological processes of mining and processing of ore and thereby improve the quality of products supplied to the metallurgical stage and reduce overall production costs

Borehole logging based on ultrasonic measurements

The coefficient of ultrasound attenuation is noted for sufficient sensitivity to provide high-quality characteristics of rocks. Efficiency of transforming electromagnetic signals into elastic oscillations of the ferromagnetic rock and backward depends on magnetic permeability of the rock, i.e. the content of the ferromagnetic component. The suggested method enables receiving additional data on concentration and structure of the ferromagnetic component distributed in the rock. To use the method one does not need either borehole liquid or any specific devices to introduce elastic oscillations into the rock, this fact facilitating its extensive application

Formation of the adaptive fuzzy model of the rock geological structure for exploratory drilling

The authors suggest an approach aimed at improving the technology, increasing energy efficiency and quality of controlling borehole drilling in mining various mineralogical-technological types of iron ore through applying a geological structure model based on data of measuring drilling parameters of a drilling rig (drilling rate, torque, energy characteristics) and rock properties on the basis of studying regularities of changing parameters of the specifically formed ultrasonic field. In rapidly changing conditions of borehole drilling, it is offered to apply a two-level adaptive optimization strategy implying a simultaneous investigation into drilling and improvement of control over this process by means of the adaptive fuzzy system

Evaluation of the Sedimentation Process in the Thickener by Using the Parameters of Longitudinal Ultrasonic Oscillations and Lamb Waves

Water is widely used in the mining industry, particularly in mineral enrichment processes. In the process of magnetic separation or flotation of crushed ore, a concentrate (an enriched product), and tailings (a product with a low content of a useful component) are obtained. One of the main tasks of enrichment processes is the efficient use of water resources. This is achieved by reclaiming and subsequent reusing water contained in ore beneficiation products by extracting it in industrial thickeners. Optimizing this process makes it possible to reduce water usage in the mining industry, reduce costs of mineral enrichment processes, and address extremely urgent environmental protection problems. To evaluate the process of sedimentation of the solid phase in the pulp within the thickener, measurements of parameters of longitudinal ultrasonic oscillations and Lamb waves that have traveled a fixed distance in the pulp and along the measuring surface in contact with it are used. The proposed approach allows for the consideration of pulp density, particle size of the solid phase in the ore material and the dynamics of changes in these parameters in the thickener at the initial stage of the sedimentation process. Based on the obtained values, adjustments can be made to the characteristics of its initial product, leading to reduced water usage and minimized loss of a useful component

Sustainable development of mining processes based on mechanochemical leaching of ore

Intensive development of the mining and metallurgical complex results in considerable volumes of waste materials, more than half of which are produced by mining enterprises. Modern mining and processing can provide non-waste production only if mineral extraction and grade recovery from natural and technogenic mineral materials are regarded as a single technological process and the Earth surface preservation becomes a priority in determining parameters of process integration. The research is aimed at improving of the technology of metal leaching in a disintegrator through complex application of metallic ore concentration tailings. A radical step of reducing mining waste hazards is their utilization through introducing technogenic reserves of metallic ore concentration tailings into production, thus creating a new raw material base for the mining industry. Substantiation of the concept of non-waste utilization of off-grade mineral materials depends on the amount of integration of chemical leaching and mechanochemical activation in the disintegrator and is achieved by means of modern information technologies

Increasing efficiency of iron ore magnetic separation by using ultrasonic technologies

The research is aimed at solving the topical problem of enhancing efficiency of iron ore magnetic separation by applying ultrasonic technologies to identify optimal technological parameters of magnetic separation, improving controlled structural parameters of a magnetic separator and pretreating slurry by highenergy ultrasound to clean the ore material surface from fine-dispersed particles of minerals and slime, as well as disintegrate ore aggregates fed to the magnetic separator. The main tasks involve identifying regularities of influence of slurry pretreatment by high-energy ultrasound on properties of iron ore magnetic separation, determining regulations of improving technological and controlled structural parameters of the magnetic separator using ultrasonic methods, developing and substantiating methods to enhance efficiency of iron ore magnetic separation by applying ultrasonic technologies

Formation of information base for controlling settlement of solid-phase ore slurry particles in a thickener

Thickeners are process units that are often used at mining enterprises. There, they are involved in dehydration of mineral con-centration products when water is removed from wet tailings containing metal concentrates. In mineral processing, large quantities of process water are used to separate different minerals from each other, so dehydration plays a major role in ore processing and preparation for concentration. This research aims to develop methods and tools of ultrasonic measurement of characteristics of settlement of solid-phase slurry particles and to assess their possible application to the automatic control system of the thickener to improve its efficiency