Operations Research, Systems Engineering and Industrial Engineering Commons^™

Designing And Manufacturing Microelectronic Packages For High-Power Light-Emitting Diodes, Brian Wright, Jianbiao Pan, Richard Savage

Industrial and Manufacturing Engineering

A new microelectronic package was designed for a high-power light-emitting diode (LED). The objective was to build a package that enables the LED to operate with currents as high as 2 Amps. An innovative thin-film interface has been developed to electrically connect the cathode of the LED die to a 22AWG Cu wire. This thin-film interface is wirebondable and solderable, and consists of three layers: Au, Ni93/V7, and Si. Four 1 mil Au wirebonds, supporting 2A of maximum current, connect the Au thin-film to the LED die cathode. Sn96Ag4 solder is used for connecting the Ni93/V7 thin-film to the 22AWG …

In-House Development Of Scheduling Decision Support Systems: Case Study For Scheduling Semiconductor Device Test Operations, Tali Freed, K. H. Doerr, T. Chang

Industrial and Manufacturing Engineering

Most manufacturing processes can benefit from an automated scheduling system. However;: the design of a fast, computerised scheduling system that achieves high-quality results and requires minimal resources is a difficult undertaking. Efficient .. scheduling of a semiconductor device test facility requires an information system that provides good schedules quickly. Semiconductor device testing-is the last stage of the long semiconductor manufacturing process, and therefore. is subjected to customer service pressures. The cost of an off-the-shelf computerised scheduling system may he prohibitive for many companies. In addition, many companies are taken aback by other characteristics of off-the-shelf scheduling systems, such as code …

Fabrication Of Functionally Graded 3a/5a Zeolites By Electrophoretic Deposition, X. Wang, E. A. Olevsky, E. Bruce, M. B. Stern, D. T. Hayhurst

Industrial and Manufacturing Engineering

Functionally graded zeolites of molecular sieve type 3A and 5A are deposited by electrophoretic deposition (EPD) from acetone suspension with 8% volume concentration of n-butylamine as particle charging agent. The EPD characteristics of both 3A and 5A suspensions are studied. Functionally graded zeolite 3A/5A deposits are obtained at 200 V DC. Energy dispersive X-ray dispersion (EDX) analysis results confirm the graded structure. The deposited zeolites are also analysed by scanning electron microscopy (SEM). The factors influencing the deposition process are discussed.

Semester Project For Engineering Management, Paul Savory

Industrial and Management Systems Engineering: Instructional Materials

This is the semester-project for my IMSE 405/805 course on Engineering Management at the University of Nebraska-Lincoln. This team-based project required students to develop an operational plan (facility layout, required staffing, company operating policies, company benefits program) for a specified product.

The Benefits Of Automatic Data Collection In The Fresh Produce Supply Chain, Ryan Charles Panos, Tali Freed

Industrial and Manufacturing Engineering

The potential for RFID based systems to improve the safety and efficiency of a supply chain with rapidly decaying products and strict health standards is creating pressure to adopt RFID in several agricultural industries. A handful of fresh produce industry leaders currently participate in mandated pilot projects, while the industry as a whole is still intimidated by the perceived cost of RFID. Therefore in this study we attempt to validate the correlation between performance and automated data collection, paving the way to economic justification of investment in data collection technologies, such as barcode and RFID.

The majority of product in …

Detection Of Aortic Calcification During Vertebral Fracture Assessment (Vfa) Compared To Digital Radiography, John T. Schousboe, Kevin E. Wilson, Thomas N. Hangartner

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Background: Cardiovascular disease is the most common cause of mortality among post-menopausal women. Our objective was to determine whether or not lateral spine images obtained on a bone densitometer to detect prevalent vertebral fracture can also accurately detect radiographic abdominal aortic calcification (AAC), an important risk factor for cardiovascular disease independent of clinical risk factors.

Methodology/Principal Findings: One hundred seventy four postmenopausal women had bone densitometry, lateral spine densitometry imaging (called vertebral fracture assessment, or VFA), and lateral spine digital radiographs. Radiographs and VFA images were scored for AAC using a previously validated 24 point scale and a simplified, …

Preface, Hans Müller-Steinhagen, M. Reza Malayeri, A. Paul Watkinson

Heat Exchanger Fouling and Cleaning VII

No abstract provided.

Cover Page, Hans Müller-Steinhagen, M. Reza Malayeri, Paul Watkinson

Heat Exchanger Fouling and Cleaning VII

No abstract provided.

Table Of Contents, Hans Müller-Steinhagen, M. Reza Malayeri, Paul Watkinson

Heat Exchanger Fouling and Cleaning VII

No abstract provided.

Applying Technology Advancements To Improve Heat Exchanger Economic And Environmental Performance In Refinery Crude Preheat Trains, Himanshu Joshi, Fred Hoeve, Eric Van Der Zijden

Heat Exchanger Fouling and Cleaning VII

Fouling of heat exchangers in crude preheat trains is a major refinery operations business factor. It is realised that fouling cannot be completely eliminated, but considerable economic and environmental benefits are available with the proper application of improved technology in both the equipment and software asset management tools areas. This paper presents a technology update of refinery applications of a heat exchanger network analysis software to identify optimal crude preheat train cleaning.

Free Alkali-Index For Optimizing The Fuel Mixture In Biomass Co-Firing, T.E. Blomberg

Heat Exchanger Fouling and Cleaning VII

Co-firing biomass with fossil fuels provides a cheap and efficient reduction of the CO2 emissions in electricity generation. One of the main challenges in co-firing is the increased fouling and corrosion rates of the heat transfer surfaces when biomass is added to the fuel mixture. Optimization of the fuel mixture from the fouling and corrosion point of view would be an easier task, if some fuel properties would provide correlation with the fouling and corrosion rates. Currently there is no clear understanding of the most useful fuel indices. The fouling indices used in coal firing have proved to be less …

Designing Two-Phase Flow Heat Exchangers For Mitigating Fouling, C.B. Panchal, Blazo Ljubicic

Heat Exchanger Fouling and Cleaning VII

Significant progress has been made in understanding the underlying mechanisms of hydrocarbon fouling and characterizing the effects of physical and chemical parameters in single-phase flows. However, the interactive effects of two-phase flows and fouling mechanisms are poorly understood. Many of the industrial heat exchangers in refining and petrochemical processing operate under multiphase flow conditions with varying flow regimes. Fouling and localized corrosion are generally experienced due to maldistribution of vapor and liquid phases in such heat exchangers. This is because design methods are inadequate to determine localized process conditions that could induce severe fouling locally, which could also lead to …

Crystallization Fouling Behaviour Of Uranium Oxide And Alumnosilicate Scale In High Level Nuclear Waste Medium, Jonas Addai-Mensah, Jun Li, Bill Wilmarth

Heat Exchanger Fouling and Cleaning VII

During high level nuclear waste (HLNW) liquor processing in evaporators operating in the temperature range 30 - 140 °C, dissolved silica, alumina, sodium hydroxide, uranium-235 and transuranic species (e.g. plutonium-238) invariably become concentrated. As the liquor evaporation proceeds, the sodium aluminosilicate (SAS) and radionuclides may exceed their solubility limits and co-precipitate, fouling the tubes and walls of the evaporator. If the fouling process is not effectively controlled or mitigated, radionuclide scale accumulation exceeding the critical mass necessary for self-sustaining nuclear fission reaction may proceed at an alarming rate, posing a serious criticality concern. To probe the mechanisms underpinning uranium oxide-sodium …

Precipitation And Fouling In Heavy Oil–Diluent Blends, E Hong, A. Paul Watkinson

Heat Exchanger Fouling and Cleaning VII

Heavy oil fractions rich in asphaltenes were mixed with diluents containing from 0.6-25% aromatics, and the resulting blends subjected to batch precipitation experiments at 85°C, and thermal fouling tests at surface temperatures in the range 230-310ºC. Deposit compositions were determined, and are compared with suspended asphaltene composition. When the heavy oils were blended with the most aromatic diluents, precipitation and fouling were negligible. As the aromaticity of the diluents was decreased, the extent of asphaltene precipitation and the fouling rates increased. The solubility parameter of the blends, δmix, and the flocculation solubility parameter for asphaltenes, δf , were determined from …

Costs Due To Utility Fouling In China, Xu Zhi-Ming, Zhang Zhong-Bin, Yang Shan-Rang

Heat Exchanger Fouling and Cleaning VII

This paper puts forward a method for evaluating the fouling costs of boilers and turbines in power plants. Furthermore, the Huaneng Dalian Power Plant and Changshan Power Plant are taken as examples for analyzing the costs of fouling. Based on data of on-site measurements in the above Power Plants, the costs due to fouling such as excess surface area, product loss, operating maintenance and increase of product costs are calculated. Results show that the total economical loss due to boiler and turbine fouling in China reaches 4.68 billion dollars, which covers is about 0.169% GDP of China in 2006.

Crude Oil Fouling In A Pilot-Scale Parallel Tube Apparatus, B. D. Crittenden, S. T. Kolaczkowski, T. Takemoto, D. Z. Phillips

Heat Exchanger Fouling and Cleaning VII

Maya crude oil fouling reveals a seemingly straightforward dependency of initial fouling rate on surface temperature but a maximum is found in the initial fouling rate – velocity relationship which mirrors that found in a model chemical system of styrene polymerization. The linear dependency of the logarithm of the pre-exponential factor on apparent activation energy for the crude oil is also found in the styrene system. The apparent activation energy for the crude oil ranged from 26.4 kJ/mol at 1.0 m/s to 245 kJ/mol at 4.0 m/s. Such strong dependencies of apparent activation energy on velocity, even at high velocity, …

Crude Oil Fouling: Petronas Refineries Experience, M.S. Rafeen, M.F. Mohamed, M.Z. Mamot, N.A. Manan, Dr A. Shafawi, Dr M. Ramasamy

Heat Exchanger Fouling and Cleaning VII

Managing crude oil fouling has been a challenge in PETRONAS refineries. Over the past several years, numerous initiatives have been conducted in order to have better control of the situation [1][2][3][4]. The control strategy currently implemented is to periodically clean the heat exchanger based on the heat exchanger monitoring parameter and supported by antifouling chemical injection program. A review was conducted in one of PETRONAS’ refineries in order to come up with a better fouling control strategy. The review is separated into two parts. Firstly, the plant operational data for two selected hot pre-heat exchanger trains was analyzed. From the …

Scale Deposits In Porous Media And Their Removal By Edta Injection, J. Moghadasi, H. Müller-Steinhagen, M. Jamialahmadi, A. Sharif

Heat Exchanger Fouling and Cleaning VII

Formation damage has been observed in several oil reservoirs and production equipment in Iranian oil fields. Laboratory and field testing confirmed that the primary cause of damage was the build-up of calcium carbonate, calcium sulfate and strontium sulfate scale either in the perforation tunnels or in the formation sandstone nears the wellbore. Conventional acid treatments could dissolve this scale, but scale precipitation from the spent acid caused rapid productivity decline. A scale removal treatment with Na2H2EDTA has been developed that can effectively dissolve scale and chelate the dissolved metal ions. Chelation of the dissolved scale prevents scale reprecipitation. This study …

The Effect Of Fouling On Heat Transfer, Pressure Drop And Throughput In Refinery Preheat Trains: Optimisation Of Cleaning Schedules, E. M. Ishiyama, W. R. Paterson, D. I. Wilson

Heat Exchanger Fouling and Cleaning VII

Optimising cleaning schedules for refinery preheat trains requires a robust and reliable simulator, reliable fouling models and the ability to handle the thermal and hydraulic impacts of fouling. The interaction between thermal and hydraulic effects is explored using engineering analyses and fouling rate laws based on the ‘threshold fouling’ concept; the potential occurrence of a new phenomenon, ‘thermo-hydraulic channeling’ in parallel heat exchangers, is identified. The importance of the foulant thermal conductivity is highlighted. We also report the development of a highly flexible preheat train simulator constructed in MATLAB&#;/Excel&#;. It is able to accommodate variable throughput, control valve operation and …

Formation Of Gum And Deposits In An Oxygenated Naphtha Stream, Yonghua Li, Paul Watkinson, Patricio Herrera, Feridoun Fahiminia, Morgan James

Heat Exchanger Fouling and Cleaning VII

Gums formed when organic fluids are in contact with air can cause fouling of process equipment. The oxidation and formation of gum in a naphtha stream was studied in a stirred batch reactor as a function of temperature (96 to 130ºC) and at a total pressure of 584 kPa. Mixtures of air and nitrogen in the pressurizing gas gave dissolved oxygen contents in the range 10-270 ppm wt. Peroxide and existent (dissolved) gum contents were measured over periods of up to 80 hours. Rates of reaction were low, with maximum concentrations of peroxide typically below 4 meq/L, and gum formation …

Observation Of An Isokinetic Temperature And Compensation Effect For High Temperature Crude Oil Fouling, C. A. Bennett, R. S. Kistler, K. Nangia, W. Al-Ghawas, N. Al-Hajji, A. Al-Jemaz

Heat Exchanger Fouling and Cleaning VII

The initial fouling rates of four crude oils were determined at a nominal bulk temperature of 315 °C, an initial heated wall shear stress of 13 Pa, and initial surface temperatures between 375 and 445 °C. These initial fouling rates ranged from 1.3(10-6) to 7.8(10-5) m2 K/kJ. Corresponding Arrhenius plots were linear with the initial fouling rates passing through an isokinetic temperature of 407.5 °C. A plot of the natural logarithm of the preexponential factors (7.6(104) – 5.2(1015) m2 K/kJ) versus the apparent activation energies (128 – 269 kJ/mol) was also linear, confirming the validity of the isokinetic temperature and …

Investigation Of The Mechanisms Of Heat Exchanger Corrosion In A Municipal Waste Incineration Plant By Analysis Of The Raw Gas And Variation Of Operating Parameters, C. Deuerling, J. Maguhn, H. Nordsieck, B. Benker, R. Zimmermann, R. Warnecke

Heat Exchanger Fouling and Cleaning VII

The detailed mechanism of high temperature chlorine corrosion, the dominant cause of corrosion in a municipal solid waste incinerator (MSI), has still to be clarified (Schroer, 2002). Upon its way through the boiler the raw gas is subject to various physical and chemical processes and interactions. Of these, sulphation of chlorides is supposed to have the major impact on chlorine corrosion (Neumann, 1997). The physical and chemical mechanisms of corrosion were investigated at a municipal solid waste incinerator. Both, the particulate and gas phase of the flue gas, were chemically and physically analyzed during their way through the boiler, at …

Study Of An Organic Crystallization Fouling Problem, Hirofumi Inokuchi, Mitsutaka Nakamura, Yoshio Koga

Heat Exchanger Fouling and Cleaning VII

One of the aromatic compound plants in Mitsubishi Chemical Corporation has a heavy crystallization fouling problem. We have been studying the crystallization process using the shell and tube heat-exchanger. In order to solve our fouling problem of the heat exchanger, we developed the specified evaluation equipment (crystallization fouling simulator : CFS) which consists of a single tube heatexchanger (Tube size: ID=10.3mm Length=500mm). The result of the modeling for describing the crystallization fouling rate and the countermeasure of the fouling problem are discussed in this work. It can be possible to describe the fouling rate as one equation which has two …

Milk Protein Fouling In A Tubular Heat Exchanger: Effect Of Milk Temperature And Reynolds Number, D.H.G. Pelegrine, K.F. Oliveira, M.T.M.S. Gomes

Heat Exchanger Fouling and Cleaning VII

In the present work, β-lactoglobulin fouling phenomenon was studied, when milk flowed in a tubular heat exchanger, where hot water was used to raise milk temperature. Experiments have been carried out to determine the effect of Reynolds number and fluid temperature in whey protein fouling, in a tubular heat exchanger and the results showed that fouling increases as the fluid temperature increases. In addition, as the Reynolds number increases, the total amount of fouling (obtained by integrating the whole amount of deposit down the tube dividing by the total area) decreased.

The Thermo-Hydrodynamics Of A Concentric Ohmic Heater For Processing Dairy Fluids, H.J. Tham, X.D. Chen, B. Young, B. Bansal, L. Zhang, G. Duffy

Heat Exchanger Fouling and Cleaning VII

The thermo-hydraulic performance of a 300W concentric annular ohmic heater was investigated. To minimize possible electrochemical reactions and corrosion, a higher frequency was applied and factors of field strength and frequency were studied. 2D computer simulation solving momentum, thermal and electrical energy was performed using the FlexPDE software. A good agreement between experimental and analytical analysis of static heating was obtained. There were significant differences between calculated and measured wall temperature near the entrance. The calculated outlet temperature was however in reasonable agreement with the experiment value.

Influence Of Different Surface Materials On Nucleation And Crystal Growth In Heat Exchangers, T. Geddert, S. Kipp, W. Augustin, S. Scholl

Heat Exchanger Fouling and Cleaning VII

The influence of different materials on the fouling tendency in saline calcium sulfate solution was investigated. The effects of the untreated material on the crystallization process have been studied experimentally in the micro- and macroscopic scale. The crystallization in the induction period was visualized with SEM and AFM to locate preferred nucleation spots and to visualize the crystal growth. The different materials are showing different crystal growth behavior (number and size of the crystals). These results are corresponding with the macroscopic fouling results with limited shear stress. Also different roughness values on stainless steel have been studied with respect to …

Fouling In A Centritherm Evaporator With Whey Solutions, R. S. Jebson, H. Chen, O. H. Campanella

Heat Exchanger Fouling and Cleaning VII

Fouling caused by sweet cheese whey and reconstituted whey powder solutions was studied in a Centritherm evaporator, the behaviour being estimated by measuring the change in the overall heat transfer coefficients with the time. It was found that there was no fouling detectable for the reconstituted whey powder solution. For sweet cheese whey, the fouling rate was linked strongly with the evaporating temperature and temperature difference. Visual observation showed that the deposit layer on the evaporator surface was very thin and soft, and like the type A milk deposit described by other investigators. A high velocity of liquid film delayed …

Simulation Of Calcium Phosphate Deposition On Stainless Steel Surfaces: A New Approach Based On Cellular Automata, F. G. Martins, T. Campos, R. Rosmaninho, L. F. Melo

Heat Exchanger Fouling and Cleaning VII

Fouling caused by calcium phosphate upon heating is basically a crystallization/precipitation process, which starts with the formation of stable clusters of ions or molecules in a process called nucleation that occurs either in the bulk liquid or at the surface. The cellular automata are useful tools to model complex systems of the universe. They could be considered as a good alternative to differential equations and have been used to model many physical/biological systems. In this preliminary work, a two dimensional space was considered where the cellular automata lattice was represented as a grid of squares, with each square representing a …

Experimental Investigation Of Crystallization Fouling On Grooved Stainless Steel Surfaces During Convective Heat Transfer, A. Al-Janabi, M.R. Malayeri, H. Müller-Steinhagen

Heat Exchanger Fouling and Cleaning VII

The beneficial aspects of enhanced or extended heat transfer surfaces may be off-set if operated under fouling conditions. In the present paper, preliminary experimental results for crystallization fouling of CaSO4 solutions onto surfaces with different structures are reported. Flat stainless steel plates (50 mm x 59 mm) with 'V' shaped grooves on the side of fluid flow were used as heat transfer surfaces. Experiments were carried out both under clean and fouling conditions to discern how the same surface structures perform under such circumstances. In addition, the impact of both, the direction of grooves with respect to fluid flow (crossed, …

A Real Time Monitoring Model Of The Calcium Carbonate Fouling Induction Period Based On The Conductance Titration, S.R. Yang, S.X. Cao, L.J. Chen, Z.M. Xu, M.L. Yu, W.H. Sun, K.L. Zheng

Heat Exchanger Fouling and Cleaning VII

A new method has been developed to monitor the calcium carbonate fouling induction period (CCFIP) in real time. Based on the conductance titration, this paper investigated the forming process of CCFIP by a staticdynamic combined simulation experiment unit. With the help of titration analysis (that is titrimetry), an accurate definition of CCFIP and the corresponding real time monitoring model were built up. The investigation results show that the proposed model applies not only to measure the CCFIP in real time, but also applies to an investigation of the influence of various factors on the CCFIP.