Chemical Engineering Commons^™

Model-Based Energy Analysis Of An Integrated Midrex-Based Iron/Steel Plant, Abdelhamid M. Ajbar, Khalid I. Alhumaizi, Moustafa A. Soliman, Emadadeen Ali

Chemical Engineering

This article presents modeling and simulations of an integrated plant for the production of steel using the direct reduced iron (DRI)=electric arc furnace (EAF) route. In a previous work (Alhumaizi et al., 2012), a comprehensive mathematical model of an iron plant based on MIDREX technology was developed, validated, and simulated. In this article, the model is extended to account for an empirical model of an EAF plant. Numerical simulations were carried out for the effect of different operating parameters of the integrated plant. Useful profiles as well as a summary table were compiled to illustrate the results of the sensitivity …

Studies Of Influencing Factors For Shale Gas Reservoir Performance, Jiaqi Wang

Masters Theses

"Shale gas resource plays a significant role in energy supply worldwide. For economic production of shale gas, technologies of horizontal well and hydraulic fracturing are used for shale gas reservoirs. Therefore, the productivity of the shale gas reservoirs will be influenced by both reservoir condition, and hydraulic fracture properties.

In this thesis, parameters that will influence shale gas production were classified into two categories: reservoir properties and hydraulic fracture properties. Published shale gas simulation studies were surveyed for determining the typical ranges of those properties. CMG-GEM was employed to finish the reservoir simulation work, and CMG-CMOST was used to complete …

Computational Fluid Dynamics (Cfd) Modeling Of Proppant Transport In A Plug-And-Perf Completion With Different Perforation Phasing, Jinlin Zhang

Masters Theses

"Perf-and-plug is a completion technique commonly used in multistage fracturing. Fracture performance modeling assumes that fluid and proppant distributes uniformly among all perforations along the length of the wellbore in a plug and perf completion Crespo et al. (2012) has conducted a limited proppant flow experiment using a 63 foot stage, and three 0.42 inch, zero phased simulated perforations. His work demonstrates proppant does not distribute evenly, but the work is limited to a single perforation scheme.

In this study, Computational Fluid Dynamics (CFD) software has been used to simulate proppant transport and distribution in a single stage of a …

Gold-Magnetite Nanoparticle-Biomolecule Conjugates: Synthesis, Properties And Toxicity Studies, Akshay Pariti

Masters Theses

"This thesis study focuses on synthesizing and characterizing gold-magnetite optically active magnetic nanoparticle and its conjugation with biomolecules for biomedical applications, especially magnetic fluid hyperthermia treatment for cancerous tissue. Gold nanoparticles have already displayed their potential in the biomedical field. They exhibit excellent optical properties and possess strong surface chemistry which renders them suitable for various biomolecule attachments. Studies have showed gold nanoparticles to be a perfect biocompatible vector. However, clinical trials for gold mediated drug delivery and treatment studied in rat models identified some problems. Of these problems, the low retention time in bloodstream and inability to maneuver externally …

Data Mining And Statistical Analysis Of Completions In The Canadian Montney Formation, Mustafa Adil Al-Alwani

Masters Theses

"This thesis documents a data-mining study and statistical analysis of well completion methods and their impact on production for more than 3300 horizontal wells in the Canadian Montney resource play.

The statistical software JMP is used to analyze well and production data for both horizontal Montney gas and oil wells, examining production trends with changes in completion parameters, such as the type of completion, fluid volume pumped, proppant load, number of fracture stages and completion costs. The analysis also provides a general understanding of average treatment characteristics, and how completions have changed with time for the Montney play.

Among the …

Evaluation Of Prosper For Modeling Long Lateral Gas Well Productivity In Toe Up, Toe Down, Horizontal Well Geometry, Abdussalam Mahmoud Mohamed

Masters Theses

"Most horizontal wells are not truly horizontal and may be drilled 'toe-up' or 'toe-down' to follow geological formations or in an attempt to keep the well from loading up. Challenges in directional drilling may also lead to horizontal gas wells with undulating wellbore profiles. This wellbore profile creates natural traps for heavy fluids in the lows and light fluid in the highs, which may result in chocked production. Hence, there is an interest in determining the best wellbore trajectory - toe-up, horizontal, or toe-down - for well unloading.

This study evaluates the capability of the well productivity software PROSPER to …

Numerical Simulations For Wellbore Stability And Integrity For Drilling And Completions, Nevan Christopher Himmelberg

Masters Theses

"Conventional wellbore trajectory planning is commonly based on an Andersonian state of stress [SoS] and the optimum well azimuth and inclination for a specific depth can be determined using stereographic projections of the safe mud weight window. In this thesis a new methodology using the complete stress tensor is developed to determine optimal well trajectories for complex in-situ stress scenarios. This study uses a 3D finite element analysis to simulate the SoS based on an integrated 3D MEM. The model yields the complete stress tensor at every location for a planned future well path. Using standard equations to determine the …

The Effect Of Using Different Rock Failure Criteria In Wellbore Stability Analysis, Reza Rahimi

Masters Theses

"Determination of the appropriate drilling fluid density by rock failure analysis is an essential step to control wellbore instability. To determine wellbore failure stresses, the rock strength has to be known, an appropriate constitutive model has to be selected, and finally an accurate rock failure criterion must be chosen. Linear-poro elastic modeling of the mechanical wellbore failure is the most common approach to investigate wellbore instability. Numerous failure criteria have been used for the rock failure analysis but there is not any commonly accepted agreement of which failure criteria to use. Rock failure criteria differ in two main characteristics. First, …

Preformed Particle Gel Transport Through Fractures, Hao Zhang

Doctoral Dissertations

"Polymer gel treatment is one of the most cost-effective methods to control water production in mature oil fields. The main objective of gel treatments is to reduce water or gas flow through high-permeability channels or fractures without damaging productive zones. Preformed particle gels (PPGs) have been applied for conformance control because they can overcome some potential drawbacks inherent in an in-situ gelation system.

In this study, lab experiments were performed to quantify PPG propagation through fractures and fracture-like channels by using screen models and open fracture models. The main findings in these experiments can guide the selection of best particle …

Study And Pilot Test On A Novel Eor Method - Coupling Ppg Conformance Control And Surfactant Flooding, Farag Awadh Muhammed

Doctoral Dissertations

"The interest in enhanced oil recovery (EOR) methods has re-emerged in recent years; however, significant challenges remain for the widespread deployment of these methods. One major downside to the successful application of EOR technologies in mature reservoirs is conformance problems (e.g. heterogeneity). To mitigate these problems, a novel EOR method which couple preformed particle gel (PPGs) conformance treatment with traditional surfactant flooding in one process is introduced.

This dissertation provides a comprehensive study for the proposed method. A series of laboratory tests were carried out to understand the chemical interaction between PPGs and surfactants. A new method to evaluate PPGs …

Degradable Nanocomposite Preformed Particle Gel For Chemical Enhanced Oil Recovery Applications, Paul Tongwa

Doctoral Dissertations

”This work presents two new materials that can be potentially used in conformance control to increase ultimate oil recovery from mature oilfields.

The first product is a degradable nanocomposite preformed particle gel for enhanced in-depth mobility control. Three different types of degradable nanocomposite preformed particle gels were synthesized. These three nanocomposite hydrogels were made using Laponite XLG, Calcium Montmorillonite, and Sodium Montmorillonite nanomaterials. It was observed that after degradation, Laponite XLG nanocomposite hydrogels had the highest post-degradation viscosity (4437 cp), followed by sodium nanocomposite hydrogels (129 cp), and lastly calcium nanocomposite hydrogels (75.5 cp). Thus, degradable Laponite XLG nanocomposite hydrogels …

Metathesis Reaction Of Ethylene And 2-Butene On Molybdenum-Based Catalysts, Benjamas Netiworaruksa

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation studies and develops the supported molybdenum catalyst for metathesis reaction of ethylene and 2-butene to produce propylene. It was found that the major factor affecting the catalytic performance for metathesis reaction is the catalyst support. From this study, it was firstly revealed that the suitable support for molybdenum-based catalyst is the mixed support of alumina and zeolite. The catalyst containing alumina support prepared from aluminium nitrate physically mixed with HBeta support could provide high selectivity of propylene. The optimum ratio of the composite support of alumina and zeolite was 3:1. However, the most optimum support obtaining propylene selectivity …

การประมาณค่าสภาพด่างฟีนอล์ฟทาลีนและค่าสภาพกรดรวมในกระบวนการเตรียมพื้นผิวชิ้นงานด้วยวิธีการถดถอยบางส่วนกำลังสองน้อยที่สุด, ชลธร ช้างพิงงา

Chulalongkorn University Theses and Dissertations (Chula ETD)

ในกระบวนการเคลือบสี กระบวนการเตรียมพื้นผิวชิ้นงาน (Pretreatment process) เป็นการดำเนินงานที่สำคัญมากงานหนึ่ง ประกอบด้วยขั้นตอนการล้างด่าง (Degreasing step) เพื่อล้างเอาฝุ่นรวมถึงคราบไขมันออกจากชิ้นส่วนผลิตภัณฑ์ และขั้นตอนการเคลือบผิวโลหะ (Coating step) เพื่อเพิ่มพฤติกรรมการต้านทานการกัดกร่อนของโลหะ กระบวนการนี้ใช้สารเคมีเป็นจำนวนมาก ส่งผลให้เกิดมลภาวะทางน้ำ และเกิดค่าใช้จ่ายที่เกี่ยวข้องในการบำบัดน้ำเสีย ความสามารถในการควบคุมเข้มข้นของสารละลายในกระบวนการเตรียมพื้นผิวชิ้นงานให้อยู่ในช่วงที่เหมาะสมก่อให้เกิดการใช้สารเคมีอย่างมีประสิทธิผล และส่งผลถึงคุณภาพของผลิตภัณฑ์ ความเข้มข้นของสารทำความสะอาดในบ่อล้างไขมันสามารถตรวจวัดได้ด้วยการไตเตรทค่าสภาพด่างฟีนอล์ฟทาลีน (Phenolphthalein Alkalinity: P-Alkalinity) และความเข้มข้นของสารละลายบ่อการเคลือบผิวสามารถตรวจวัดได้โดยการไตเตรตค่าสภาพกรดรวม (Total-Acidity) กระบวนการนี้ทำโดยคนนำมาซึ่งความผิดพลาดที่ไม่น่าพอใจ ดังนั้นการควบคุมความเข้มข้นของสารละลายในบ่อทั้งสองจึงกลายเป็นเรื่องที่ยากมากื งานวิจัยนี้จึงมุ่งเน้นการประมาณค่าสภาพด่างฟีนอล์ฟทาลีน และค่าสภาพกรดรวม ซึ่งแสดงถึงความเข้มข้นของสารละลายในบ่อล้างไขมันและบ่อเคลือบผิวตามลำดับ โดยอาศัยตัวแปรที่วัดค่าได้ ค่าความเป็นกรด-ด่าง ค่าสภาพการนำไฟฟ้า ค่าความหนาแน่น และอุณหภูมิ กระบวนเตรียมพื้นผิวชิ้นงานของโรงงานแห่งหนึ่งในอุตสาหกรรมผลิตเครื่องปรับอากาศจะนำมาใช้เป็นกรณีศึกษา วิธีการประมาณนี้จะอาศัยหลักการทางสถิติ และวิธีการถดถอยบางส่วนกำลังสองน้อยที่สุด (Partial Least Squared Regression: PLS) งานวิจัยพบว่าวิธีนี้จะให้ค่าประมาณสภาพด่างฟีนอล์ฟทาลีน และค่าสภาพกรดรวมที่มีค่าความคลาดเคลื่อนสูงสุดอยู่ที่ร้อยละ 7.45 และ 4.29 ตามลำดับ

อิทธิพลของสารต้านจุลินทรีย์ซิงค์ออกไซด์และคาร์วาครอลต่อสมบัติของบรรจุภัณฑ์อาหารที่เตรียมจากพอลิบิวทิลีนซัคซิเนต, ศสิณี วิบูรณวงศ์

Chulalongkorn University Theses and Dissertations (Chula ETD)

พอลิบิวทิลีนซัคซิเนต (PBS) เป็นพลาสติกย่อยสลายได้ทางธรรมชาติกลุ่มพอลิเอสเทอร์ ที่มีสมบัติใกล้เคียงกับพลาสติกจากปิโตรเคมี งานวิจัยนี้มุ่งพัฒนาฟิล์มบรรจุภัณฑ์อาหาร PBS ที่สามารถต้านเชื้อจุลินทรีย์ได้โดยการเติมสารต้านจุลินทรีย์ 2 ชนิด คือ ซิงค์ออกไซด์ (ZnO) ซึ่งจัดอยู่ในกลุ่มสารต้านจุลินทรีย์จากสารเคมี และคาร์วาครอล (Carvacrol) ซึ่งเป็นสารต้านจุลินทรีย์จากธรรมชาติ งานวิจัยนี้ศึกษาอิทธิพลของปริมาณสารต้านจุลินทรีย์แต่ละชนิด ร้อยละ 2, 4, 6, 8 และ10 โดยน้ำหนัก ต่อการยับยั้งเชื้อ E.coli (แบคทีเรียแกรมลบ) และ S.aureus (แบคทีเรียแกรมบวก) พร้อมทั้งศึกษาอิทธิพลของความหนาของฟิล์ม PBS ที่ผสมสารต้านเชื้อจุลินทรีย์แต่ละชนิด ระดับความหนา 50 75 และ 100 ไมโครเมตร ต่อสมบัติเชิงกลและการยับยั้งเชื้อ ผลการทดสอบบริเวณยับยั้งเชื้อ (Clear zone) ด้วยวิธีการแพร่ในอาหารเลี้ยงเชื้อแบบแข็ง (Agar diffusion method) พบว่า เริ่มพบบริเวณยับยั้งเชื้อ S.aureus และพบบริเวณยับยั้งเชื้อ E.coli เมื่อเติม ZnO ร้อยละ 6 โดยน้ำหนัก สำหรับฟิล์มหนา 50 ไมโครเมตร ในทำนองเดียวกัน เริ่มพบบริเวณยับยั้งเชื้อ S.aureus เมื่อเติม Carvacrol ร้อยละ 4 โดยน้ำหนัก แต่เริ่มพบบริเวณยับยั้งเชื้อ E.coli เมื่อเติม Carvacrol ร้อยละ 6 โดยน้ำหนัก ผลการทดสอบสมบัติเชิงกล พบว่า ฟิล์ม PBS/ZnO มีระยะยืด ณ จุดขาดและความต้านทานแรงกระแทกลดลง เมื่อปริมาณ ZnO มากขึ้น เพราะอนุภาค ZnO เป็นสารอนินทรีย์ที่มีความแข็งมากกว่า PBS และ ZnO มิได้สร้างพันธะยึดติดกับ PBS ดังยืนยันโดยผลทดสอบ FTIR การตรวจดูระดับจุลภาค พบ ZnO จับตัวเป็นกลุ่มก้อนเมื่อปริมาณ ZnO …

Effect Of Additives In Lubricant On Cobalt-Iron Alloy Lapping, Wiraya Anamnart

Chulalongkorn University Theses and Dissertations (Chula ETD)

To maintain this flying height of read-write head (called slider) at 12 nm across the disk, read and writer elements will be lapped to meet designed surface roughness, surface topography, as well as magnetic property. The writer element was made from cobalt-iron alloy (CoFe). Final lapping process of sliders uses lubricant to control surface morphology and to avoid corrosion. The aim of this study was to determine the effect of additives on corrosion protection of CoFe. The corrosion was studied by potentiostat technique and atomic force microscopy (AFM). Water content was determined by Karl Fischer method. Thin film passivation was …

A Post-Installed Subsea Monitoring System For Structural And Flow Assurance Evaluation, David Brower, Alexis Brower, John Hedengren, Reza Asgharzadeh Shishavan

Faculty Publications

This paper describes major advancements for deploying sensing systems on existing subsea structures as part of the Clear Gulf study. In the past, a major shortcoming of post-installed monitoring systems has been poor coupling between the sensor and structure; this study provided methods to overcome this problem. Both subsea field testing and laboratory testing were performed to verify these advancements. The Clear Gulf study is a collaboration between the offshore energy industry and NASA with the goals of risk mitigation, safety, efficiency and environmental concerns in the offshore energy industry. The study is ongoing and has investigated new methods to …

Co2 Char Gasification Rates Of Sawdust, Switchgrass, And Corn Stover In A Pressurized Entrained-Flow Reactor, Thomas H. Fletcher, Aaron D. Lewis, Emmett G. Fletcher

Faculty Publications

An entrained-flow flat-flame burner reactor was used to measure apparent CO2 gasification rates of near-spherical biomass chars of poplar sawdust, switchgrass, and corn stover using particle residence times1258−1891 K and 6.1− 13.5 atm, respectively. A new method was developed to produce near-spherical particles from nonspherical biomass chars. The apparent CO2 gasification rates for the three biomass chars with mean diameters near 100 μm were fit to a global first-order model, and the optimal kinetic parameters are reported. The measured gasification rate of poplar sawdust was about 3.9 times faster than that of switchgrass char, but only about 20% faster than …

Co2 Gasification Rates Of Petroleum Coke In A Pressurized Flat-Flame Burner Entrained-Flow Reactor, Aaron D. Lewis, Emmett G. Fletcher, Thomas H. Fletcher

Faculty Publications

Two petcoke samples were gasified by CO2 at total pressures of 10 and 15 atm in a high-pressure flat-flame burner reactor at conditions where the bulk phase consisted of either 40 or 90 mol % CO2 with gas temperatures up to 1909 K. Particle diameters of 45−75 μm were used in the experiments. The morphology of the two petroleum coke chars was drastically different and evaluated using scanning electron microscopy images of the chars. The mass release data caused by CO2 gasification of the petcoke chars were fit to a global first-order model, and the optimal kinetic parameters are reported. …

Application Of L-Systems To Geometrical Construction Of Chamise And Juniper Shrubs, Dallan R. Prince, Marianne E. Fletcher, Chen Shen, Thomas H. Fletcher

Faculty Publications

Improved models of fire spread and fire characteristics are desired for live shrub fuels, since the majority of existing research efforts focus on either dead fuel beds or crown fires in trees. Efforts have been made to improve live fuel modeling, including detailed studies of individual leaf combustion, with results incorporated into a shrub combustion model for broadleaf species. However, this approach was not well-suited to non-broadleaf shrubs since their fuel consists of long needle-covered branches rather than easily discretized leaves. Methods were therefore developed to simulate the branching structure of chamise (Adenostoma fasciculatum) and Utah juniper (Juniperus osteosperma). The …

Simulation Of The Swelling Of High-Volatile Bituminous Coal During Pyrolysis, He Yang, Sufen Li, Thomas H. Fletcher, Ming Dong

Faculty Publications

In this paper, a model is established to predict the swelling ratio of high-volatile bituminous coal during pyrolysis, based on the assumption that the structure of bubble distribution in the particle at the beginning of the plastic stage is a central bubble surrounded by many surrounding bubbles. The initial number and size of the bubbles when the particles become plastic are calculated by the pressure in the particle. The chemical percolation devolatilization (CPD) model is used to describe pyrolysis. The pyrolysis of eight types of high-volatile bituminous coals is simulated, and the results are compared with experimental results to verify …

Differences In Burning Behavior Of Live And Dead Leaves, Part 1: Measurements, Thomas H. Fletcher, Dallan R. Prince

Faculty Publications

Burning behaviors of individual live and dead leaves were measured in a well-instrumented, well-controlled flat-flame burner. Manzanita (Arctostaphylos glandulosa) branches were harvested from the Chaparral near Riverside, California. Leaves were conditioned to several moisture contents. Two “live” (i.e., not fully dried) groups remained above the fiber saturation point at 34% moisture content (MC; dry basis) and 63% MC. Two “dead” groups were dried to about 4% MC, and one was rehydrated back up to 26% MC. Distinct plateaus in surface temperatures at 175◦C were observed while burning live leaves, but dead leaves showed weaker plateaus, if any. Evidence of high …

Characterization Of Macromolecular Structure Elements From A Green River Oil Shale, I. Extracts, Mark S. Solum, Charles L. Mayne, Anita M. Orendt, Ronald J. Pugmire, Jacob Adams, Thomas H. Fletcher

Faculty Publications

This paper is the first of two associated papers describing the structural details of three sections of an oil shale core taken at the Skyline 16 mine in the Utah Uinta Basin. Bitumen was extracted from the shale using methanol/dichloromethane. Kerogen was isolated from the shale, using a nine-step extraction procedure using HCl and HF. Bitumen samples from the three cores were analyzed using high-resolution ¹³C NMR liquid-state spectroscopy, showing carbon aromaticities of 7%−11%. Aliphatic carbons were dominated by methylene structures, with average aliphatic chain lengths of 24 carbons. The three parent shales and the demineralized kerogens were each …

Coke Deposition On Wox/Sio2 Catalyst Physically Mixed With Magnesium Oxide For Metathesis Reaction Of Ethylene And 2-Butene, Thidaya Thitiapichart

Chulalongkorn University Theses and Dissertations (Chula ETD)

The presence of MgO physically mixed with silica supported tungsten oxide catalysts was investigated in metathesis reaction using ethylene and trans-2-butene as feeds. Adding MgO could enhance the conversion of trans-2-butene and propylene yield, comparing with a catalyst mixed with SiO2 as a referenced one. However, the presence of MgO with silica supported tungsten oxide catalysts surprisingly elevated the coke deposition. The coke precursor was formed by MgO from isomerization of undesired products like C5+ and moved to deposit on the acid sites of silica supported tungsten oxide catalysts which is a coke site of the catalysts. Furthermore, the distance …

Modification Of W/Sio₂ Catalysts By Second Metal For Metathesis Of Ethylene And 2-Butene, Narongrat Poovarawan

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, the main goals were to study the effect of the dispersion of the tungsten active phase and the modification of WO3/SiO2 catalyst by a second metal for metathesis reaction of the mixture of cis/trans-2-butene and ethylene. The silica supported tungsten catalyst was used as the base catalyst and lanthanum, cerium, yttrium were used as the second metal in this study. It was found that the dispersion of the tungsten active phase would affect the catalytic performance of the WO3/SiO2 catalyst, when the mixture of cis/tran-2-butene was use as feed.The second metal was used to midify the dispersion …

Comparison Of Role Of Nano-Sized Extra Supports On Pt-Based Catalyst For Propane Dehydrogenation And Wox-Based Catalyst For Propene Metathesis, Adisak Guntida

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this thesis, the role of nano-sized extra supports was studied. The different types of nano-sized supports (ZrO2, TiO2, Al2O3, and SiO2) were physically mixed with WOx-based catalysts for propene metathesis reaction and Pt-based catalysts for propane dehydrogenation reaction as extra support. The dispersions of active sites were improved in both metathesis and dehydrogenation catalysts by the addition of nano-sized extra supports. The migration of active sites from the main catalyst onto the nano-sized extra support during thermal treatment via thermal spreading is a key for this improvement. The surface energy of nano-sized extra support and concentration of metal active …

Suitable Catalyst Bed Arrangement Of Silica-Based Supported Tungstenand Hydrotalcite Catalysts For Propylene Production From 1-Butene, Sirada Sripinun

Chulalongkorn University Theses and Dissertations (Chula ETD)

The research studied the design of suitable catalyst beds of hydrotalcite and the modified silica supported tungsten for propylene production from 1-butene. The study started with performing reactions at various values of gas hourly space velocity, feed composition and temperature. Then the reaction rate expressions for each catalyst were determined. It was found that the models could predict well the experimental results. The models were further used to simulate the reaction performance of reactors packed with different catalyst beds. The performance was shown in terms of molar flow rate of propylene and yield of propylene. The performance of the catalyst …

The Effects Of Additives In Ethylene Glycol Based Lubricant On Slider Lapping Process, Patara Paranusorn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Lapping process is a key technology in magnetic recording head manufacturing process. Thin film of metal alloys and metal oxides are fabricated on ceramic substrate called wafer to create the recording heads. In order to control surface properties of the recording head, the precise chemical mechanical nano grinding process is used. In this process the recording heads are treated to achieve the designed surface properties by using lubricants to control the selectivity of material removal. The aim of this study was to determine the effects of additives in ethylene glycol based lubricant on the selectivity of material removal of slider …

Polydopamine As Active Templates For Fabrication Of Conductive Of Copper Line Pattern, Raweewan Thongprachan

Chulalongkorn University Theses and Dissertations (Chula ETD)

In this research, copper conductive patterns were fabricated on polyethylene terephthalate (PET) substrate by combination of spray drying of polydopamine nanoparticles, and consequently electroless plating process. The polydopamine nanoparticle ink was synthesized by self-polymerization of dopamine hydrochloride at different initial pH 8, 8.5, 9 and 10. The patterns were deposited by site-selective Cu electroless plating process on top of the PDA pattern at the controlled temperature 30 C. The effects of plating time in electroless plating and storage time were studied. Moreover, the adhesion and aspect ratio were also investigated. The conductive lines fabricated were characterized by two-point probe measurement, …

Design Of Plantwide Control Structure Of A Small-Scale Concentrated Solar Power Process Cooperated With Organic Rankine Cycle And Thermal Storage Systems, Pathawut Bua-Ngam

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work presents a study on control system design of a small-scale electricity generation process for household applications using plantwide control technique. The process are of three sections including parabolic trough solar collector, thermal energy storage, and organic Rankine cycle system. Synthetic oil Dowtherm©A and acetone were chosen as heat transfer fluid and working fluid, respectively. In terms of control objectives, the control structure can keep the process operation at maximum efficiency and response the required work load. Control performance of the control structure proposed is tested under various disturbance changes by using dynamic simulator (SIMSCI DYNSIM). The scenarios investigated …

Simulation Of Temperature Distribution In A Thermal Drying Oven Based On Three Dimensional Cfd Model, Patsarawan Lipikanjanakul

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research presents a study of air velocity in a thermal drying oven in drying zone. To reduce a heat loss, a mass flow rates are decreased from 100% to 10%. The effect of the mass flow rate can be divided into three parts; air velocity, air temperature, and concentration of solvent. A three-dimensional CFD with a non-isothermal model and a transport of diluted species were simulated by using COMSOL. For ensuring the result, all results are compared with MATLAB program by focusing in two-direction (length-height). The parameters of air velocity that uses in this program is the results of …