Applied Linear Analysis for Chemical Engineers

<div class="htmlview paragraph">This paper discusses the transfer of engineering analytical technology between the automobile and aerospace industries. The role of predictive analysis within both industries is addressed, with a particular emphasis on secondary safety. The use of non linear computer analysis techniques is discussed with particular reference to an accident involving a Boeing 737-400 in the UK in 1989. The accident resulted in the author's organisation performing correlated injury studies by occupant kinematic analysis, which are described in outline.</div>

Forensic Chemical Engineering Investigation and Analysis

During this reporting period, primary efforts were expended on process system properties, chemical engineering and economic analysis. Analysis of process system properties was continued for silicon source materials under consideration for producing silicon. The following property data are reported for dichlorosilane which is involved in processing operations for silicon: critical constants, vapor pressure, heat of vaporization, heat capacity, density, surface tension, thermal conductivity, heat of formation and Gibb's free energy of formation. The properties are reported as a function of temperature to permit rapid engineering usage. Major efforts were expended on completion of the preliminary economic analysis of the BCL Process (Battelle Columbus Laboratories). Cost analysis results for the process (Case A-two deposition reactors and six electrolysis cells) are presented based on a preliminary process design of a plant to produce 1000 metric tons/year of silicon. Fixed capital investment estimate for the plant is $12.47 million (1975 dollars) ($17.47 million, 1980 dollars). Product cost without profit is %8.63 $/kg of silicon (1975 dollars) (12.1 $/kg, 1980 dollars).

Politeknik Katolik Mangunwijaya (Polteka Mangunwijaya) is a higher education institution formed by the merger of three academies in Semarang. These three academies combined to become popular study programs among the community, offering Diploma III programs in Chemical Engineering, Pharmacy, and Health Analysis. Over time, Politeknik Katolik Mangunwijaya encountered challenges in managing inventory to support organizational effectiveness and decision-making by the structural leadership. To optimize asset management, a web-based inventory information system application was developed. The choice of the web platform was based on its compatibility with all devices. The system was built using the Rapid Application Development (RAD) method with PHP programming language, the Laravel framework, Tailwind CSS, and a MySQL database. This application primarily supports the vice director, superadmin, and program study admins in stock recording, item identification using barcodes, and detailed inventory transaction reporting. This system replaces the manual recording method, which was previously considered inefficient and prone to data loss or inaccuracies. After functional testing and user acceptance, the system has proven to operate smoothly as planned and provides an effective solution for managing inventory at Politeknik Katolik Mangunwijaya.

Engineering systems modeling and analysis based on the bond graph approach has been applied to biomolecular systems. In this context, the notion of a Faraday-equivalent chemical potential is introduced which allows chemical potential to be expressed in an analogous manner to electrical volts thus allowing engineering intuition to be applied to biomolecular systems. Redox reactions, and their representation by half-reactions, are key components of biological systems which involve both electrical and chemical domains. A bond graph interpretation of redox reactions is given which combines bond graphs with the Faraday-equivalent chemical potential. This approach is particularly relevant when the biomolecular system implements chemoelectrical transduction - for example chemiosmosis within the key metabolic pathway of mitochondria: oxidative phosphorylation. An alternative way of implementing computational modularity using bond graphs is introduced and used to give a physically based model of the mitochondrial electron transport chain To illustrate the overall approach, this model is analyzed using the Faraday-equivalent chemical potential approach and engineering intuition is used to guide affinity equalisation: a energy based analysis of the mitochondrial electron transport chain.

The employment of chemometric methods is becoming increasingly widespread in several sciences, such as analytical chemistry, engineering and environmental chemistry. Response surface methodology based on statistical design of experiments has several important advantages over univariate analysis for the elucidation of the environmental relevance of photochemical reactions and their contribution to the abiotic transformation of contaminants, including a reduced number of experiments and possibilities to evaluate interactions among variables. The latter is very important considering the complicated indirect photolysis mechanisms that govern the overall fate of organic micro-pollutants. The theoretical background and several critical issues of the discussed chemometric methods are explained, while experimental work with regards to the photolytic transformation of diuron, in natural water as well as in the presence of a variety of photosensitizers, is comprehensively presented.

In the process design of chemical production plants, dynamic simulation plays an important role. This paper gives a short introduction to the process modeling tool ProMoT and the simulation tool Diana. Both are open‐source programs intended for the dynamic analysis of chemical engineering and biological systems. They support the implementation and analysis of large nonlinear differential algebraic systems. An overview is given on the functionality of ProMoT and Diana. The use of the tools is illustrated by their application to an innovative fluidized bed crystallization process.

Through an iterative process over nine semesters, the freshman Chemical Engineering Analysis course in Mississippi State University's Swalm School of Chemical Engineering has evolved into a problem-based design experience using the LEGO NXT® robotics kits integrated with Vernier® sensor technology and auxiliary bench-scale equipment (e.g. pumps, valves, piping and tanks). Integrating a variety of skills important to engineering practice, this course engages students in critical thinking; team-building; integration of mathematics, chemistry and physics; a systems approach to open-ended problem solving; and, the application of concepts, data collection and analysis with actual systems construction and testing. The use of the reasonably-priced LEGO NXT® robotics kits allows replication of multiple robotically-controlled “mini plant” units across a large class (60+), enabling student design teams to simultaneously, yet creatively and uniquely develop solutions to a variety of process design problems.

The present Energy Analysis and Diagnostic Centers program, sponsored by the U.S. Department of Energy is in transition from providing industrial energy audits to providing industrial assessments. This paper presents the perspective of one of the centers which is currently undergoing this transition. This process of transition includes a change from the point of view of training future energy engineers. Currently, the focus is on energy management engineering for the U.S. manufacturing sector. The new focus will include multi-facet assessments for energy savings, waste minimization, and process improvements. The expanded role of the newly-converted centers combines an interdisciplinary approach of engineering analysis which includes the traditional engineering disciplines of electrical, mechanical, chemical, and industrial engineering. These newly-converted centers have the responsibility to perform industrial assessments, hence the new name for these centers is Industrial Assessment Centers indicating the transition from recommending energy conservation opportunities to broader-based assessments. This paper will give examples of the expanded scope in assessments for various technologies showing the role of each of the three facets, i.e. energy savings, waste minimization and process improvements. The technologies include alternative refrigerants, reclamation & recycling, pollution prevention technologies, natural gas opportunities and new high-efficiency products. Illustrations from future casemore » studies might show some compounding effects for opportunities which were not previously diagnosed as economically feasible, which are now becoming more attractive. The compounding effects are not limited to the interdependence of energy savings and waste minimization but also the improved process gains.« less

This paper evaluates the seismic resistance and vulnerability of an existing unreinforced masonry (URM) building in Zagreb's Folnegovićevo neighborhood. The building with potentially low seismic resistance was erected in the 60s, a period characterized by the introduction of the first seismic code in practice. It has a rectangular plan 36.9 m x 10.7 m and consists of a basement, a ground floor and four floors totaling 17 m in height. The solid brick walls with variable thickness are evenly distributed in both directions and they run continuously from the foundation to the top. The reinforced concrete slabs are 14 cm thick rigid diaphragms made of MB 20 concrete class with smooth rebars GA 240/360.Two structural variants were analyzed: one with reinforced tie-beams and one without. Equivalent Static Analysis was conducted manually and , a Time-History Linear Dynamic Analysis was performed with the Tower Radimpex software for preliminary assessment. This method provided a basic assessment of the building’s seismic resistance, while also comparing manual and numerical results. Two advanced methods, Nonlinear Time-History Analysis (NLTH) and Pushover Analysis, were conducted with Diana FEA software employing Engineering masonry constitutive law to describe the highly nonlinear behavior of masonry walls which can crush, crack, or fail in shear. NLTH simulated the building's response to the 2020 earthquake, identifying critical structural components and potential damage. The Pushover Analysis evaluated how the building responded to increasing lateral loads, focusing on seismic resilience and collapse mechanisms.This research provides an in-depth comparison of different analytical approaches, contributing to the methodology for assessing and strengthening existing buildings. Conclusions drawn from these analyses emphasize recommendations for modifications to improve structural performance and safety.

本研究は，太子食品工業株式会社とともに, 豆類加工プロセスを食品化学工学的手法で評価・定量し，高効率な生産加工技術を確立することを目的に実施した一連の共同研究の成果である．まず，緑豆スプラウトの高密度従属栄養栽培手法の確立を目的に，有効係数を指標とすることで散水条件の効果の定量化を試みた．その結果，散水流量を制御することにより物質移動の寄与を高めることで高密度栽培でも単一個体栽培に匹敵する効率を維持できることを実験的に明らかにした．次に，豆乳チーズ様食品開発のための製造技術確立を目的に，高圧処理による発酵プロセスの加速化について検討した．高圧処理ではいずれの条件においても前指数因子の自然対数と活性化体積には線形関係が認められ，エンタルピー・エントロピー補償効果が観察された．この結果に基づき，加圧条件を最適化することで発酵プロセスを1週間程度に短縮することに成功した．

The role of Computer Aided Process Engineering in physiology and clinical medicine

The chemical engineering analysis and stress analysis for design of the 30-Mw intermediate heat exchanger and steam generator for service with a liquid- sodium heattransfer fluid are presented. The chemical engineering analysis includes the inert-cover-gas system, control of liquid level, and design provisions for system pressure relief. Consideration is given to possible hazards resulting from a steam-to-sodium leak. The stress analysis section covers those thermal transients that would be physically possible with this intermediate heat exchanger and steam generator design. Attention was given to methods of operation that would minimize the magnitude and frequency of thermal shocks. A structural design basis for handling stress analysis of combined mechanical, hydrostatic, and thermal stresses and conditions for using creep and stress-rupture properties is included. (M.C.G.)

The order-disorder transition of a sphere-forming block copolymer thin film was numerically studied through a Cahn-Hilliard model. Simulations show that the fundamental mechanisms of pattern formation are spinodal decomposition and nucleation and growth. The range of validity of each relaxation process is controlled by the spinodal and order-disorder temperatures. The initial stages of spinodal decomposition are well approximated by a linear analysis of the evolution equation of the system. In the metastable region, the critical size for nucleation diverges upon approaching the order--disorder transition, and reduces to the size of a single domain as the spinodal is approached. Grain boundaries and topological defects inhibit the formation of superheated phases above the order--disorder temperature. The numerical results are in good qualitative agreement with experimental data on sphere-forming diblock copolymer thin films.
 Received: 22 August 2017, Accepted: 12 December 2017; Edited by: R. Dickman; Reviewed by: A. Peters, Dept. Chemical Engineering, Louisiana Tech Univ., Ruston, USA; DOI: http://dx.doi.org/10.4279/PIP.100001
 Cite as: L R Gómez, N A García, R A Register, D A Vega, Papers in Physics 10, 100001 (2018)
 This paper, by L R Gómez, N A García, R A Register, D A Vega, is licensed under the Creative Commons Attribution License 4.0.

The growing concern of many countries globally about the greenhouse gas emissions have emphasized interest towards dry reforming of methane (DRM). For an oil and gas based economy such as the state of Qatar, CO2 emission is a big challenge, as it has rendered Qatar as the highest CO2 emitting country per capita in the world. The potential of DRM process for integration in the existing infrastructure of Qatar is a key aspect of this research as a part of exceptional proposal granted to Dr. Nimir Elbashir by QNRF aimed at CO2 fixation. DRM is a heterogeneous chemical reaction in which the two greenhouse gases; CH4 and CO2 are converted to synthesis gas. Synthesis gas or ‘syngas’ is a precursor to a large variety of value added chemicals including hydrocarbons via Fischer-Tropsch Synthesis (FTS). In addition to CO2, steam can also be used to reform methane into syngas in a process known as steam reforming of methane (SRM). Steam Reforming of Methane (SRM) ΔH298 = 206 kJ/mol (1) Dry Reforming of Methane (DRM) ΔH298 = 247 kJ/mol (2) In addition to these two processes, there is also an exothermic reforming process, known as the partial oxidation of methane (POX), where methane is combusted to yield syngas. DRM process is beset by numerous major process limitations including its high endothermicity, high rate of catalyst deactivation (due to carbon formation) and low-quality syngas yield ratio (H2:CO⇐1:1). These challenges have posed severe obstruction towards widespread commercialization of this technique. A synergistic amalgamation of the reforming of methane as DRM+SRM, DRM+POX and DRM+SRM+POX have been recommended in the literature as a way to tackle the intrinsic limitations of the DRM process. In the current work, such combinations of methane reforming processes have been simulated thermodynamically using direct Gibbs free energy (GFE) minimization method. Energy valuations of various case scenarios have been carried out under varying operating conditions (temperature, presssure and feed mole ratios) assuming both ideal gas conditions and non ideal regimes using cubic equations of state (Peng Robinson (PR), Redlich Kwong (RK) and Soave Redlich Kwong). The main objective of the thermodynamics aspect of this study is to find optimized condition of reduced energy requirement and reduced carbon deposition while maintaining considerable CO2 fixation in a combined reforming process. In order to completely understand the system, a one-dimensional pseudo-homogeneous fixed bed reactor model which incorporates all the transport limitations (heat, mass and momentum) for combined SRM/DRM processes is developed. Reaction kinetics utilizing Langmuir-Hinshelwood Hougen-Watson (LHHW) type rate expressions published in the literature for SRM and DRM under analogous operating conditions have been used in the reactor bed model. These model results will be further validated against the experimental data published in literature. The kinetic conversion profiles are then compared with the thermodynamic results to systematically determine the regimes of kinetic deviation (from equilibrium) for the combined SRM/DRM system. This approach of carrying out both thermodynamic and reaction engineering analysis is advantageous in understanding the reforming process in a broader view and will also help in setting base for experimental investigations. These modeling results will be used as pre-experimental initial findings for the NPRP exceptional project aimed towards development of highly effective and coke resistant catalysts.ReferencesPakhare, D. and J. Spivey, A review of dry (CO2) reforming of methane over noble metal catalysts. Chemical Society Reviews, 2014. 43(22): p. 7813-7837.Song, C., Tri-reforming: a new process for reducing CO2 emissions. Chemical Innovation, 2001. 31: p. 21-26.Jiang H, Li H, Zhang Y., Tri-reforming of methane to syngas over Ni/Al2O3—thermal distribution in the catalyst bed. Journal of Fuel Chemistry and Technology 2007. 35: p. 72-78.Noureldin, M.M.B., N.O. Elbashir, and M.M. El-Halwagi, Optimization and Selection of Reforming Approaches for Syngas Generation from Natural/Shale Gas. Industrial & Engineering Chemistry Research, 2014. 53(5): p. 1841-1855.