Catalytic Reaction Engineering – CHEN30051&30041&30251: Coursework Assignment 1 Catalytic Reaction Engineering CHEN 30051 & 30041 & 30251 Coursework: Continuous Assessment Task This coursework is related to the following ILOs: x ILO4 – Apply analytical and numerical methods to determine reactor behaviour and analyse the results. x ILO5 – Design (size) heterogeneous chemical reactor and optimise operating conditions. The aim of this coursework is for you to understand how we can apply the fundamental basics of CRE to chemical engineering design, and to undertake extra research into the design of a packed bed reactor system. This coursework is mainly focused on Topic 4 (Software packages as a tool in reactor design) and Topic 5 (Solid-fluid reactor design – Packed bed reactors). The coursework is worth 30% of the unit assessment. Further reading: x Fogler, Elements of Chemical Reaction Engineering, 5th Edition. x Luyben, Chemical Reactor Design and Control, 2007. 1. Introduction Consider the elementary heterogeneous gas phase catalytic reaction in an ideal packed-bed reactor: A + B o C The rate of reaction is given by: ′ = ′ (in kmol s–1 kg-catalyst –1) where PA and PB are the partial pressures (in bar) of A and B respectively and k’ is the specific rate constant (in kmol s–1 bar –2 kg-catalyst –1). Catalytic Reaction Engineering – CHEN30051&30041&30251: Coursework Assignment 2 Table 1. Key kinetic and physical parameters. Heat of reaction ‘HR kJ kmol–1 -23,237 Activation energy E kJ kmol–1 69,710 Pre-exponential factor A kmol s–1 bar–2 (kg-catalyst) –1 0.19038 Heat capacities CPA kJ kmol–1 K-1 30 CPB kJ kmol–1 K-1 40 CPC kJ kmol–1 K-1 70 Molecular weights MA kg kmol–1 15 MB kg kmol–1 20 MC kg kmol–1 35 Gas viscosity P kg m–1 s–1 0.18 x 10–4 Heat transfer coefficient U kW m–2 K–1 0.227 Table 2. Operating and design parameters (unique for each group). Inlet Conditions: Pressure P0 bar Temperature T0 K Total molar inlet flow rate FT0 kmol s–1 mol-fraction of A yA0 – mol-fraction of B yB0 – Catalyst Properties: Porosity (void fraction) I – Catalyst particle size Dp m Catalyst bulk density Ucatalyst, bulk kg m–3 Reactor Information: Reactor diameter Dreactor m Reactor length Lreactor m Cooling temperature Ta K 4 . 6 357 0 . 62 0 . 37 0. 63 0. 46 00 15 000 Catalytic Reaction Engineering – CHEN30051&30041&30251: Coursework Assignment 3 2. Assignment 2.1 Main task Develop and design packed bed reactor units for the following three scenarios: CASE A: Single adiabatic PBR CASE B: Adiabatic reactor with interstage cooling CASE C: Cooled PBR with constant cooling medium temperature The following information should be included: x Justification of various underlying assumptions used in making the design calculations. x Justification that the design will work, e.g., does it follow key rules of thumb. x Develop of source code: user-friendly (including comments, guidance etc.) for reuse by another design engineer and effectiveness in coding methods. x Profile plots for temperature, composition, conversion, pressure, etc. down the length of the reactor. Analyse and evaluation of each case should be discussed from an operational and economic viewpoint: CASE A: Single adiabatic PBR Use the operating and design parameters provided to your group in Table 2 and discuss the effect of the following variables on the different profiles: x Inlet temperature is varied. x Inlet pressure is varied. x Particle diameter is changed: Consider at what particle size pressure drop becomes important for the same catalyst weight (assume the porosity doesn’t change). x Reactor diameter and length is changed for the same overall weight of catalyst. CASE B: Adiabatic reactor with interstage cooling Use two (2) cooling stages with the same conditions as in CASE A (same overall weight of catalyst) and discuss the effect of the following variables on the profiles: x Cooling temperature: How does the temperature of the cooling in each stage effect the profiles x Inlet temperature is varied. x Reactor diameter and length is changed (keeping the catalyst weight the same). CASE C: Cooled PBR with constant cooling medium temperature Use the same conditions as in CASE A (same overall weight of catalyst) but with a cooling temperature Ta and discuss the effect of the following variables on the profiles: x Cooling temperature is varied. x Inlet temperature is varied. x Reactor diameter and length is changed (keeping the catalyst weight the same). Catalytic Reaction Engineering – CHEN30051&30041&30251: Coursework Assignment 4 2.2 Deliverables Specifically, you are to prepare the following for submission (submission will be done through blackboard): 1. A written coursework report. Please submit your report file as “_report.pdf”, example for the group Gary it will be Gary_report.pdf. 2. A copy of your source code (Matlab/Python/Polymath). Please submit all relevant code files that clearly include your groupname. 2.3 Written report One report should be submitted per group. The written report should comply to the page limit for each section. Formatting should be Arial-font, font size 11, line spacing single and text alignment as justified. The following sections should at least be included: x Title page (maximum 1 page) o Group name and number o Students names and numbers (alphabetical order) x Section 1 – Results and Discussion: Case A (maximum of 2 pages) This section presents all the relevant results obtained and interpretation thereof for Case A. x Section 2 – Results and Discussion: Case B (maximum of 2 pages) This section presents all the relevant results obtained and interpretation thereof for Case B. x Section 3 – Results and Discussion: Case C (maximum of 2 pages) This section presents all the relevant results obtained and interpretation thereof for Case C. x Section 4 –Discussion: (maximum of 2 pages) Discuss advantages and disadvantages of all the cases together from an operational and economic standpoint. Are there any alternative configurations to consider Draw a flowsheet for one of the CASE B or CASE C that include ancillary equipment. . x Section 5 – Source code and file names submitted (no pag
e limits) This section presents all the source code develop to solve the coursework and the relevant file names. Only source code. Please keep to the report section lengths; if the section lengths are exceeded, when marking we will stop marking that section at the page limit. Catalytic Reaction Engineering – CHEN30051&30041&30251: Coursework Assignment 5 3. Assessment Criteria The coursework will be evaluated according to the following main criteria in the design report: 1. Analysis and Evaluation of Scenarios i. Discussion on CASE A ii. Discussion on CASE B iii. Discussion on CASE C iv. Discussion on all cases 2. Effective Communication of Design Report. 3. Code to solve ODEs After completion of this assessment the group will receive feedback on their performance in the form of a feedback report that looks like the one given below: Group Name: Criteria of evaluation Assessment weighting Group mark / % Design Report- 1. Analysis and Evaluation of Scenarios: i. CASE A 15% ii. CASE B 15% iii. CASE C 15% iv. All cases 15% 2. Overall Structure, Style, and Presentation 20% 3. Code to Solve ODEs* 20% Total: 100% *Take note your welcome to use any software such as MATLAB, Python, Polymath, etc. Catalytic Reaction Engineering – CHEN30051&30041&30251: Coursework Assignment 6 Criteria 1: Analysis and Evaluation of Scenarios Range Description CASE A Mark CASE B Mark CASE C Mark ALL CASES High 1st (≥80%) Exceptional representation of results with figures and/or tables that are clear, easy to read, consistent and aid effective communication. The discussion part demonstrates a high level of critical evaluation that is supported with insightful and comprehensive interpretation and deep understanding of the results. High-quality analysis of constrains justification. The results are rigours and very convincing sound/valid. 1st (70%-79%) Good representation of the results with figures and/or tables that are clear, easy to read, consistent and aid effective communication. The discussion part demonstrates a good critical evaluation that is supported with insightful interpretation and understanding of the results. Strong independent lines of argument presented. High level of discussion and analysis of constrains. The results are sound/valid. Upper 2nd (60%-69%) Good representation of results with figures and/or tables that are clear, easy to read, consistent and aid effective communication. The discussion part demonstrates a good evaluation of results with adequate interpretation and understanding. Adequate analysis and justification of results, assumptions and calculations with some faults/shortcomings. The results are arguable convincing. Lower 2nd (50%-59%) The results are adequately representation with figures and/or tables that are clear, easy to read, consistent and aid effective communication. The results are adequately explained. Some conceptual ability and grasp of analysis and justification. Calculations with few weaknesses. The results are nearly plausible. Pass/3rd (40%-49%) Representation of the results with figures and/or tables is reasonably clear and easy to follow. Basic level of analysis and justification of results and calculations with some significant weaknesses. Some errors in the results and interpretation are evident. Fail (<40%) Bad or no attempt of presenting the results. Inability to obtain solutions using standard design procedures, rules of thumb, etc. Insufficient analysis and justification or no attempt of presenting analysis and calculations. Superficial understanding of concepts and significant gaps and/or errors in the results. Comments Catalytic Reaction Engineering – CHEN30051&30041&30251: Coursework Assignment 7 Criteria 2: Overall Structure, Style, and Presentation Range Description Mark High 1st (≥80%) Exceptional quality that is highly reader-friendly and contains no grammatical or spelling mistakes. 1st (70%-79%) Excellent written report with almost no blunders. There is a high level of coherence throughout the report, with a clear flow and logical links between the sections. All the figures and tables are clear and aid effective communication. Upper 2nd (60%-69%) Good written report with a clear English style, minor grammar, and spelling mistakes. Structure, figures, and tables are clear, consistent and aid effective communication. Lower 2nd (50%-59%) Adequately written report with several grammar and spelling mistakes. Inconsistencies in structure but the majority of the report retains a clear exposition that can be followed and understood. Pass/3rd (40%-49%) The report is poorly written with poor grammar, many spelling mistakes and little attempt to adhere to the instructions. Errors impede effective communication. Fail (<40%) The report is badly written that is lacking in logical structure, difficult to read and no attempt has been made to adhere to the instructions for the report. Comments Criteria 3: Code to solve ODEs Range Description Mark High 1st (≥80%) The numerical source code is working with no errors. Source code representation is excellent, clear and easy to following with detail comments and guidance new users. An exceptional way of code developed that is well- structured, easy to follow and user friendly to change for different scenarios. (The numerical results are very convincing sound/valid.) 1st (70%-79%) The numerical source code is working with no errors. Good source code representation that is clear and easy to following with comments for guidance. A user-friendly way of code development for analysis purposes. (The numerical results are very convincing sound/valid.) Upper 2nd (60%-69%) The numerical source code is working with no errors. The code is clear and easy to following (generally user-friendly) with some comments. (The numerical results are arguably valid.) Lower 2nd (50%-59%) The numerical source code is working with minor mistakes. Source code is clear and adequate to follow and understand. (The results are nearly plausible.) Pass/3rd (40%-49%) The source code is poor (incorrect) with significant gaps or errors. Fail (<40%) No source code (software-files) is handed in or the source code is very bad (do not work) with major errors and gaps. Comments