Operation Of Process Equipment Research Articles

КРИТЕРИАЛЬНАЯ МОДЕЛЬ ОЦЕНКИ УРОВНЯ ПОЖАРНОЙ ОПАСНОСТИ ТЕХНОЛОГИЧЕСКОГО ОБОРУДОВАНИЯ ВОДОРОДНОЙ ЭНЕРГЕТИКИ

The work is aimed at the solving the problem of fire safety by quantitative risk assessment during the operation of process equipment where hydrogen-containing gas is used, transported or stored. Such process areas mainly include hydrogen storage tanks, electrolysis plants, rooms containing hydrogen receivers, hydrogen compressor stations, etc. The list of hydrogen gas fire hazard indicators is presented in the work, the ways of definition of these indicators (parameters of criterial model) for a technological site are described, on the basis of the developed program for electronic computing machine the method of reference of technological object to a certain risk category is offered. This model is applicable only for closed technological sites where apparatuses and (or) pipelines in which hydrogen-containing gas with purity not less than 99,9 % is circulating are placed.

Experimental Study of an Industrial Tower-Type Supporting Frame with Facades Subjected to the Stationary Wind Effect

Aerodynamic studies of canceled structures are important for design of buildings, analysis of air flows inside buildings, evaluation of buildings’ effects on air flow patterns of the adjoining area, and optimal choice of enclosing structures. The analysis of wind effects during the design of canceled structures is governed by codes and standards of general purpose. These statutory documents do not regulate the mounting procedure of wind protection screens, nor do they contain the analysis of wind effects on structures with different angles of attack of an incident wind flow. The codes prescribe aeroelastic model testing in special civil engineering wind tunnels during the design of such structures. The purpose of this research project is to analyze wind effects on the force and torque specification of a canceled structure at different wind effect angles accounting for the mounting sequence of wind protection screens. The subject of the article is an experimental aeroelastic study of wind effects on a canceled structure accounting for sequential mounting of wind protection screens on the structure’s facade. The obtained data will allow for the analysis of effects of the wind flow angle on internal forces of the structure, given that a change in its permeability is taken into account. At the initial design stage, experimental modeling of wind effects in a wind tunnel is thereby considered a structure model validation step. The relevance of the paper lies in the need to identify optimum operating conditions of canceled structures, subjected to a wind effect, to ensure safe and comfortable work of people and reliable operation of process equipment installed inside the facility.

Methods to improve the efficiency of the business process of repairing power-generating equipment

The paper considers the methods to improve the efficiency of the business process of repairing power-generating equipment, as one of the main directions for increasing the efficiency and safety of the company activity as a whole. The efficiency of power generating companies is currently determined by the quality of the field-oriented and supporting business processes arrangement. Companies in the power-generating sector have strict environmental and energy security requirements. Accidents at production and transport facilities can cause irreparable environmental deprivations. Also, the failure of the mains sections can completely stymie the work of large settlements, and endanger the life and health of people in the cold season. The performance of the equipment can be impaired as a result of natural causes (corrosive wear, metal fatigue, and other deformations) and due to violation of the operating mode. The good condition of the processing equipment is ensured by the maintenance and repair works performed in time. Company's experience has proven that, for the safe operation of processing equipment, it is necessary to annually appropriate funds in the amount of at least 2% of the initial cost of the equipment. The main focus should be on planning and arranging the processes involved. Safe operation can also mean availability to purchase equipment necessary for production tasks. Many large power generating companies are trying to act under the principle of technological self-sufficiency. It implies the presence of technological developments in intellectual property, as well as production facilities. The implementation of this principle is possible both through the development of own scientific resources, and through the absorption of industrial enterprises. All this gives a competitive advantage to power generating companies, as well as expands the range of services provided.

Operation of process equipment with crack-like defects

Analysis of the ‘layer separation’ defect of the base metal depending on the depth of its occurrence on the further safe operation of process equipment is carried out. The calculation is performed by the finite element method using ANSYS software package. The obtained results enable one to conclude that the layer separation does not have a significant effect on the bearing capacity of the equipment, while it is local and not being distributed.

Внедрение и оценка эффективности системы предварительной осушки газа при эксплуатации технологического оборудования установки комплексной подготовки газа

Внедрение и оценка эффективности системы предварительной осушки газа при эксплуатации технологического оборудования установки комплексной подготовки газа

Wet clay adhesion to antistick coatings: effects of binder type and surface roughness

The handling of sticky raw material can cause problems during operation of process equipment in the cement production industry. These handling problems are generally observed when raw material (e.g., wet clay) sticks to machine walls and causes blockage of outlets. This leads to frequent production shutdowns and expensive cleaning operations. In this work, the effects of surface material and process parameters on the friction forces between wet clay and surface were investigated. Various surface materials and clay impact speeds were investigated. The results demonstrate that not only the equipment surface material but also the surface roughness influences the observed frictional behavior. The ranking of the materials in terms of effective static friction coefficients fell in two groups with equal performance within the group: (1) Two Teflon-based coatings (Accofal 2G54 and Accolan LB), polished AISI 304 stainless steel, Matrox lining, and a polyurethane-based coating (best performing surfaces), (2) Mild steel, a silicone-based coating, and AISI 304 stainless steel (worst performing surfaces). However, the friction coefficients of the two groups only varied by a factor of two, suggesting that adhesion of wet clay to surfaces is difficult to avoid by the use of coatings.

Development of optimal modes and mathematical models of energy performance of electric steelmaking production

The article deals with the issues of determining the optimal modes of electric steelmaking production on the basis of analysis of the graph of changes in the average power and voltage of the arc furnace in one meltdown cycle. In addition, empirical equations for determining the flow rate and specific energy consumption during the operation of process equipment under normal conditions were obtained for the main equipment of the electric arc-furnace shop using the mathematical method.

About the need of carrying out researches of wear resistance of groups of mating parts for ensuring anticipatory scheduling of repair influences

The article shows the role of scientifically substantiated system of planning as the function of management of technical maintenance and repair of the equipment on the basis of the analysis of the factors influencing durability of operation of processing equipment of the industrial enterprises. It is shown that the use of system of fixed-schedule maintenance allows: to prepare the controllable and predictable over a long time period repair program according to the types of repair, the types of equipment , the workshops and the whole enterprise; to predict material, financial and labor resources, necessary capital investments in development of production base of repair service; to carry out preliminary preparation of repair work, to carry out them in the minimum terms; it increases the quality of repair and, finally, increases the reliability of the equipment.

Advancements in hydrate phase equilibria and modeling of gas hydrates systems

Reliable hydrate phase behavior predictions are critical to petroleum and natural gas processing and design, and operation of process equipment. Inaccurate predictions of phase equilibria can also lead to erroneous design of process facilities and subsequently may cause safety hazards and flow assurance issues. This work reviews the experimental data on hydrate phase equilibria in the presence of inhibitors (Salts + Organic Inhibitors). The statistical thermodynamic model of van der Waals and Platteeuw for hydrate phase equilibria prediction is also critically reviewed. Recent studies have shown that the basic assumptions of the van der Waals and Platteeuw model, including the spherical symmetry of molecules, no guest–guest interactions, and no lattice distortions (due to guest molecules) can introduce errors in the predicted results. In addition, the limitations of the fluid phase models, which do not account for the effect of hydrogen bonding and electrolyte contributions, can lead to severe prediction errors in hydrate forming systems containing polar hydrate formers, inhibitors, and salts, especially at high concentrations. Thermodynamic predictions of gas hydrate phase equilibria for polar hydrate formers and inhibited systems (e.g., NaCl, KCl, CaCl2, and also methanol, ethanol, Ethane-1,2-diol) are of major concern because of the large errors in fluid phase equilibrium predictions. The unavailability of phase equilibria data, an appropriate electrolyte model, and an associative equation of state as well leads to various problems in predicting the properties of aqueous associating fluids and inhibited systems.

Airborne PM2.5 characteristics in semiconductor manufacturing facilities

This study aimed to elucidate the concentrations and physicochemical properties of airborne PM2.5 during the normal operation of process equipment and scrubber in semiconductor manufacturing facilities, including the clean room (CR), plenum, clean sub fab (CSF), and facility sub fab (FSF). Number and mass concentrations of PM2.5 in the main facilities, such as the CR, plenum and CSF ranged ND-4.766 #/cm3 and ND-1.072 µg/m3, respectively, and for FSF, ranged 9.261–134.088 #/cm3 and 0.574–25.941 µg/m3. The concentration levels of PM2.5 in the FSF (excluding CR, plenum, and CSF) were partially affected by the PM levels in outdoor air. The particles of 0.3–1.0 µm corresponding to PM1 for number and mass concentrations accounted for 98.44–99.67% and 75.00–96.43%, respectively, of PM2.5, which contains 0.3–2.5 µm particles. In all particles, O and Si were detected in common, and also Al, F, Fe, Mg, K, Ca, and Ti elements were intermittently detected according to the sample. The elemental compositions of airborne particles in the FSF were almost coincident with those of the particles sampled in outdoor air. No particles were evident on the filter media in the CR and CSF. The morphology of the observed particles was spherical and nearly spherical based on the primary particle, and the size ranged approximately 1.5–6.0 µm, which means that particles were likely to be formed by the agglomeration and/or aggregation of primary particles of less than 100 nm. These results can provide useful information for the development of alternative strategies to improve the work environment and worker’s health in the semiconductor industry.

Mining Equipment Technical Condition Monitoring

The Earth, being the main object and operational basis for mining, is exposed to the greatest impact because of extracting minerals. Protection of elements of the biosphere, including subsoil, should provide for the provision of scientifically based and economically justified completeness and complexity of use. The article discusses the need to monitor the technical condition of mining equipment, as applied to assessing its technical condition and reducing energy consumption by this equipment. The dependence of energy consumption on vibration parameters and temperature of equipment surfaces is shown. The data of the results of vibration parameters monitoring are given. Criteria are given for estimating the energy efficiency of operation of process equipment and, accordingly, the influence of these parameters on the environment.

On slug frequency in concurrent high viscosity liquid and gas flow

Slug frequency is an important input parameter in most mechanistic and semi-mechanistic models used for estimating slug flow characteristics such as pressure gradient, slug length and slug holdup. It is also essential in the design and sizing of transport and/or production pipelines, process flow control, design and operation of process equipment, etc. This study experimentally investigates slug frequency in two horizontal pipelines with internal diameters (ID) of 0.0254 and 0.0764 m. Test liquids used in the study were mineral oil (with viscosity ranging from 1.0 to 4.0 Poise) and water while compressed air is the gas phase. Effects of liquid viscosity, gas superficial velocity, liquid superficial velocity, pipe internal diameter, pipe length and pressure gradient are discussed. Results indicate that slug frequency increased with increase in oil viscosity; decreased with increase in pipe diameter; and reduces along the length of the pipe. For gas Reynolds number, ReSG≤2500, slug frequency increased with increase in gas superficial velocity, when ReSG>2500, slug frequency decreased with increase in gas superficial velocity. A new slug frequency correlation that accounts for liquid viscosity and gas superficial velocity, hitherto not included in other correlations was proposed. A comparative analysis of the proposed models and existing slug frequency correlation on a high viscosity databank showed that the proposed correlation gave the best prediction with an average absolute percentage error (AAPE) of 19.91%.

MODEL VOLUMETRIC DOSING OF GROUND COFFEE ON THE BASIS OF SCADA-SYSTEM LABVIEW

About automation and mathematical model of volumetric dosing of ground coffee on the basis of SCADA - system and programming language LabView. The algorithms and functional diagram of the automation process of dispensing the ground coffee and described in the form of transfer functions of the process control parameters. This model differs from others in that it allows the use of dimensional algorithmic and computational description of data processing to produce the control signals to the drive system and the metering feeder at a presentation of the results as dynamic graphical objects by means of multi-window interface SCADA system. Product level speed drive dispenser weight in the package are controlled parameters of the system. Factors affecting as a disturbance on the accuracy of dosing with the physical and mechanical properties of the product are the degree of fullness of the hopper and the uneven flow of product to the dispensing mechanism. A more preferred method of research is the study of the process with the use of simulation techniques, than the construction of differential models. The developed control system allows you to monitor the dosing process, the level and doses of ground coffee in the migration of physical and mechanical properties and the motor controller rotary displacement metering is useful for analysis and further interpretation of the human operator in the formation of a decision on an operation of process equipment in the achievement of management objectives

Novel Design of Collaborative Automation Platform Using Real-Time Data Distribution Service Middleware for an Optimum Process Control Environment

Refining and petrochemical processing facilities utilize various process control applications to raise productivity and enhance plant operation. Client–server communication model is used for integrating these highly interacting applications across multiple network layers utilized in distributed control systems. This paper presents an optimum process control environment by merging sequential and regulatory control, advanced regulatory control, multivariable control, unit-based process control, and plant-wide advanced process control into a single collaborative automation platform to ensure optimum operation of processing equipment for achieving maximum yield of all manufacturing facilities. The main control module is replaced by a standard real-time server. The input/output racks are physically and logically decoupled from the controller by converting them into distributed autonomous process interface systems. Real-time data distribution service middleware is used for providing seamless cross-vendor interoperable communication among all process control applications and distributed autonomous process interface systems. Detailed performance analysis was conducted to evaluate the average communication latency and aggregate messaging capacity among process control applications and distributed autonomous process interface systems. The overall performance results confirm the viability of the new proposal as the basis for designing an optimal collaborative automation platform to handle all process control applications. It also does not impose any inherent limit on the aggregate data messaging capacity, making it suitable for scalable automation platforms.

Tolerance Synthesis When in Operation of Process Equipment for Electroplated Coating Application

The relevance of studying product quality control as based on optimization of process input values parameters is shown. The paper explores the tolerance synthesis method of technological process input parameters based on regression dependences. Electrolytic chromium plating process simulation has been performed enabling to optimize input parameter tolerances and upgrade process equipment. As a result of the modernization the galvanic bathtubs were outfitted for control parameters of the electrolyte, heating of the electrolyte. The modernization of electrolytic chromium plating process allowed finding of values of input parameters being within the required limits and providing for the quality of the products.

MODELING OF SCENARIOS OF DEVELOPMENT OF EMERGENCIES FOR NON-STATIONARY HAZARDOUS PRODUCTION FACILITIES OF AN OIL AND GAS COMPLEX

Results of the analysis and researches of not stationarity of technological processes and processing equipment are given in article and need of their account at design and safe operation of the hazardous production facilities (HPF) of an oil and gas complex is shown. Research and the analysis of results of inspection of conditions of emergence and development of emergencies are carried out taking into account the analysis of not stationarity of conditions of emergence and development of emergencies in the main technological modules of the ELOU-AVT installation. According to inspection the formalized models of trees of refusals and trees of events taking into account not stationarity of risks for head OPO were constructed. The analysis of development of scenarios of accidents by means of the formalized models of trees of refusals and trees of events is a component of system of the analysis and management of minimization of the risk allowing to consider influence of the striking factors, to estimate zones of defeat and to develop organizational and technical actions for early prevention of emergencies at a design stage and operation. Algorithmic providing an assessment of a relative indicator of danger of the processing equipment allowing to estimate total potential fire danger, potential of explosion and reliability of the equipment taking into account not stationarity of operation of OPO is developed. The assessment of degree of danger of OPO taking into account their not stationarity allows to develop the control system of minimization of technical risk providing safe operation of processing equipment on this basis.

IMPROVING THE SAFETY PRODUCTION OF THE SULFURIC ACID ALKYLATION

In connection with the transition to gasoline production of the new standard, is increasingly used sulfuric acid alkylation and regeneration of spent acid, which is obtained alkylate - High-quality components for gasoline 4-5 class. Installation designed to produce high octane alkylate from the alkylation process of light olefins with isobutane in the presence of a catalyst - sulfuric acid. One of the most dangerous areas of the production pipeline is transporting sulfuric acid, which in the case of a leak can cause chemical burns and poisoning her pairs. A detailed analysis of the existing polymeric materials capable of preventing fusion in contact with the membrane. Analysis showed that the Teflon coating for use as a layer between the membrane and the spindle is optimal and meets the requirements of this unit when operating in an acidic medium and high temperatures. In this paper we consider the problem of the danger of leakage, explosion and pollution at rupture of the membrane valves, poisoning attendants in manufacturing sulfuric acid alkylation. The analysis occurred in the past year showed a significant number of emergency situations involving leakage of sulfuric acid, which in some cases led to the affected people. Thus, the proposed method for eliminating leaks by applying a Teflon coating in place of clamping the membrane will eliminate the possibility of its destruction, which in turn will ensure the safe operation of process equipment in an aggressive environment and preserve the life and health of staff.

Mechanistic based DEM simulation of particle attrition in a jet cup

The attrition of particles is a major industrial concern in many fluidization systems as it can have undesired effects on the product quality and on the reliable operation of process equipment. Therefore, to accommodate the screening and selection of catalysts for a specific process in fluidized beds, risers, or cyclone applications, their attrition propensity is usually estimated through jet cup attrition testing, where the test material is subjected to high gas velocities in a jet cup. However, this method is far from perfect despite its popularity, largely due to its inconsistency in different testing set-ups. In order to better understand the jet cup testing results as well as their sensitivity to different operating conditions, a coupled computational fluid dynamic (CFD)–discrete element method (DEM) model has been developed in the current study to investigate the particle attrition in a jet cup and its dependence on various factors, e.g. jet velocity, initial particle size, particle density, and apparatus geometry.

Safety management is a virtue

AbstractIt is undeniable that safe operation and process reliability are not only compatible but highly interrelated. Reliable production units rarely have safety incidents, whereas unreliable ones tend to repeatedly experience abnormal operation. To prevent incidents, personnel, procedures, and equipment must be aligned to facilitate rapid identification and response to failures of the control system and protective safeguards. Safe and reliable performance requires minimization of the root causes that lead to abnormal and emergency operation. The challenges to accomplishing this in a timely manner are considerable, but not insurmountable.This article discusses various challenges to sustaining safe operation of process equipment. Each challenge is introduced using a philosophical saying from a Chinese fortune cookie to remind the reader that the barriers against progress are not new but have existed from many years. In most cases, the solutions are also well known and generally require deployment of robust equipment, proven techniques, and competent resources. © 2009 American Institute of Chemical Engineers Process Saf Prog 2009

Carbonaceous Material Deposition from Heavy Hydrocarbon Vapors. 1. Experimental Investigation

The unwanted deposition of carbonaceous layers can compromise the efficient operation of processing equipment, particularly for the upgrading of heavy hydrocarbons. An experimental investigation was undertaken to study deposition from the vapor in a tubular test section downstream of a bench-scale continuous bitumen coking reactor. Results of the effects on deposition of coker reactor temperature, steam addition, vapor velocity, and heating or cooling of the produced vapor are presented. Evidence suggests that physical condensation of heavy hydrocarbon species rather than vapor-phase chemical reaction is the primary cause of deposit formation. Entrained droplets of partially converted bitumen also contribute to the deposit. Morphological and chemical characteristics of the deposits are described. Preliminary data are presented on the aging of the amorphous hydrocarbon deposit into coke.