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Automated retrofit targeting of heat exchanger networks

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 630-642页

作者： Timothy G.Walmsley Nathan S.Lal Petar S.Varbanov jiri j.klemes Sustainable Process Integration Laboratory -SPIL NETME CentreFaculty of Mechanical Engineering Bmo University of TechnologyBmo 60190Czech Republic Energy Research Centre School of EngineeringUniversity of WaikatoHamilton 3240New Zealand

The aim of this paper is to develop a novel heat exchanger network (HEN) retrofit method based on a new automated retrofit targeting (ART) algorithm. ART uses the heat surplus-deficit table (HSDT) in combination with the Bridge Retrofit concepts to generate retrofit bridges option, from which a retrofit design may be formulated. The HSDT is a tabular tool that shows potential for improved re-integration of heat source and sink streams within a HEN. Using the HSDT, retrofit bridgesa set of modifications that links a cooler to a heater to save energymay be identified, quantified, and compared. The novel retrofit method including the ART algorithm has been successfully implemented in Microsoft ExcelTM to enable analysis of large-scale HENs. A refinery case study with 27 streams and 46 existing heat exchangers demonstrated the retrofit method's potential. For the case study, the ART algorithm found 68903 feasible unique retrofit opportunities with a minimum 400 kWunit(-1) threshold for heat recovery divided by the number of new units. The most promising retrofit project required 3 new heat exchanger units to achieve a heat savings of 4.24 MW with a favorable annualised profit and a reasonable payback period.

关键词： process retrofit pinch analysis heat exchanger network heat recovery

Spatial targeting evaluation of energy and environmental performance of waste-to-energy processing

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 731-744页

作者： Petar S.Varbanov Timothy G.Walmsley Yee V.Fan jiri j.klemes Simon j.Perry Sustainable Process Integration Laboratory NETME CentreFaculty of Mechanical EngineeringBmo University of Technology61669 Bmo Czech Republic Centre for Process Integration School of Chemical Engineering and Analytical ScienceThe University of ManchesterManchester M I 3ALUK

Waste-to-energy supply chains are important potential contributors to minimising the environmental impacts of municipal solid waste by reducing the amounts of waste sent to landfill, as well as the fossil fuel consumption and environmental footprints. Accounting for the spatial and transport properties of the waste-to-energy supply chains is crucial for understanding the problem and improving the supply chain designs. The most significant challenge is the distributed nature of the waste generation and the household energy demands. The current work proposes concepts and a procedure for targeting the size of the municipal solid waste collection zone as the first step in the waste-to-energy supply chains synthesis. The formulated concepts and the provided case study reveal trends of reducing the net greenhouse gas savings and energy recovery by increasing the collection zone size. Population density has a positive correlation with the greenhouse gas saving and energy recovery performance. For smaller zone size the energy recovery from waste approaches and in some cases may surpass the energy spent on waste transportation. The energy recovery and greenhouse gas savings remain significant even for collection zones as large as 200 km(2). The obtained trends are discussed and key directions for future work are proposed.

关键词： waste-to-energy supply chain optimisation GHG savings energy recovery ratio

Heat Integration retrofit analysis --an oil refinery case study by Retrofit Tracing Grid Diagram

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Frontiers of Chemical Science and Engineering 2015年第2期9卷 163-182页

作者： Andreja NEMET jiri jaromir klemes Petar Sabev VARBANOV Valter MANTELLI Centre for Process Integration and Intensification CPI2 Faculty of Information Technology Egyetem utca 10 8200 Veszprem Hungary IPLOM SpA Via C. Navone 3B 16012 Busalla Genoa Italy

Heat Integration has been established over the last decades as a proven chemical engineering methodol- ogy. Two design implementations are often used in the industry： grassroots and retrofit. Although various methods have been developed for retrofit, it still needs more development to ensure simultaneously thermodynamic feasibility and economic viability. In this paper, a novel graphical approach has been developed to facilitate the understanding of the current situation and scope of improvement. The Retrofit Tracing Grid Diagram presents all streams and heat exchangers in temperature scale and the heat exchangers are clearly separated from each other, enabling clear visualisation of the current state. The tool incorporates the previously developed Cross-Pinch Analysis as well as path approach for retrofit. Additionally, the non-vertical heat transfer can be evaluated. The application of the developed tool has been validated on an oil refinery case study. The applicability of the tool is evident as it can reveal additional options for modification that none of the previous methods considered.

关键词： Heat Integration retrofit Pinch Analysis,thermodynamic approach oil refinery

Process synthesis with simultaneous consideration of inherent safety-inherent risk footprint

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 745-762页

作者： Andreja Nemet jiri j.Kleme Zdravko Kravanja Faculty of Chemistry and Chemical Engineering University of Maribor2000 MariborSlovenia Sustainable Process Integration Laboratory NETME CentreFaculty of Mechanical EngineeringBmo University of Technology61669 Brno Czech Republic

Process plants should be designed to be economically viable and environmentally friendly, while also being operable and maintainable during process implementation. The safety of processes is among the most important considerations in obtaining results that are more acceptably realistic, as it is linked to the availability and reliability of the process. Inherent safety can effectively be enhanced in the early stages of the design, when the main decisions on process design are made. The aim of this study is to enhance and select the appropriate risk assessment method and to incorporate it into process synthesis, using a mathematical programming approach. A mixed-integer, nonlinear programming (MINLP) model was used for the synthesis of a methanol production process, considering risk assessment during the synthesis. Risk assessment is performed simultaneously with the MINLP process synthesis, where the risk is determined either for the whole process as overall risk, or on a per unitof- a-product basis. For the latter, a new measurement is proposed: the inherent risk footprint. The results of a case study led to two main conclusions: (i) Significantly safer designs can be obtained at negligible economic expense, and (ii) at higher production capacities, a lower inherent risk footprint can be achieved. The results also indicate that designs obtained using this method can have significantly increased inherent safety, while remaining economically viable.

关键词： inherent safety process design simultaneous risk assessment risk footprint methanol process

Improved theory of projectile trajectory reference heights as characteristics of meteo-ballistic sensitivity functions

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Defence Technology（防务技术） 2017年第3期13卷 177-187页

作者： Vladimir Cech jiri jevicky Department of Weapons and Ammunition University of Defence Oprox Inc. Department of Mathematics and Physics University of Defence

Projectile trajectories calculated under non-standard conditions are considered to be perturbed. The tools utilized for the analysis of perturbed trajectories are weighting factor functions(WFFs) which are a special kind of sensitivity functions. WFFs are used for calculation of meteo ballistic elements mB(ballistic wind wB, virtual temperature tB, pressure pB, density rB, speed of sound a) as well. An effect of weapon system parameters can be incorporated into calculations through the reference height of *** are also calculated from WFFs. Methods based on RHT are far more effective than traditional methods that use weighting factors *** have found that the existing theory of RHT has several shortcomings due to we created an improved theory of generalized RHT which represent a special sensitivity parameters of dynamical systems. Using this theory will improve methods for designing firing tables, fire control systems algorithms, and meteo message generation algorithms.

关键词：灵敏度函数气象要素弹道风特征动力系统理论消防控制系统加权因子生成算法

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Improved theory of generalized meteo-ballistic weighting factor functions and their use

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Defence Technology（防务技术） 2016年第3期12卷 242-254页

作者： Vladimir CECH jiri jEVICKY Department of Weapons and Ammunition University of Defence Oprox Inc. Department of Mathematics and Physics University of Defence

It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire error budget *** calculated under non-standard conditions are considered to be *** tools utilized for the analysis of perturbed trajectories are weighting factor functions(WFFs)which are a special kind of sensitivity *** are used for calculation of meteo ballistic elements B(ballistic wind w B,densityρB,virtual temperatureτB,pressure p B)as *** have found that the existing theory of WFF calculation has several significant *** aim of the article is to present a new,improved theory of generalized WFFs that eliminates the deficiencies *** this theory will improve methods for designing firing tables,fire control systems algorithms,and meteo message generation algorithms.

关键词： Exterior ballistic Non-standard projectile trajectory Perturbation Meteoconditions Sensitivity function (Generalized) weighting (factor) function(curve) (Generalized) effect function Norm effect

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Applicability limits of the DAX test in plastic bonded explosives

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Defence Technology（防务技术） 2024年第6期36卷 64-70页

作者： Martin Künzel jindrich Kucera jiri Pachman OZM Research Bliznovice 32Hrochuv Tynec 53862Czech Republic Institute of Energetic Materials Faculty of Chemical TechnologyUniversity of PardubiceStudentska 95Pardubice 53210Czech Republic

The Disc Acceleration e Xperiment(DAX)is one of the most recent experimental methods of performance characterization of new energetic materials.A cylindrical explosive charge accelerates a thin metallic disc and its velocity is measured continuously using photonic Doppler *** detonation velocity is measured *** DAX test can be used to obtain the Chapman-jouguet(Cj)detonation pressure and to describe detonation products expansion using reduced amount of explosive.A series of DAX tests was performed at various charge diameters and disc thicknesses with Semtex 1 A plastic bonded explosive and sensitized *** DAX-like evaluation was also applied to previously measured data of Semtex 1A and A-IX-1 *** optimum disc thickness is determined by the disc to explosive mass ratio of *** repeatability of the Semtex 1 A detonation pressure results is about four times lower compared to the pressed and liquid explosives.

关键词： Flyer plate Detonation pressure Photonic Doppler velocimetry Semtex

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Clinical outcomes of radiofrequency catheter ablation of atrial fibrillation in octogenarians lO-year experience of a one high-volume center

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journal of Geriatric Cardiology 2017年第9期14卷 575-581页

作者： Alan Bulava jiri Hanis Ladislav Dusek Department of Cardiology Ceske Budejovice Hospital Ceske Budejovice Czech Republic Faculty of Medicine and Dentistry Palacky University Olomouc Czech Republic Faculty of Health and Social Sciences University of South Bohemia in Ceske Budejovice Czech Republic Institute of Biostatistics and Analyses Faculty of Medicine Masaryk University Brno Czech Republic

Background Prevalence of atrial fibrillation （AF） increases with age. Radiofrequency catheter ablation （RFCA） is an establishedtreatment option superior to antiarrhythmics （AAs）. In this study, we investigated safety and efficacy of RFCA of AF in *** From our database, we extracted procedural and follow-up data for patients 〉 80 years with symptomatic AF undergoing RFCAand compared this population to RFCA patients 〈 50 years. All patients underwent pulmonary vein isolation （PVI） supplemented by linearlesions in PVI-nonresponders. Arrhythmia-free survival was assessed using seven day Holter every three months post procedure. All patientscompleted their 12 months follow-up. Results Fifty patients aged ≥80 years （80.5 ± 1.6 years） were compared to 259 patients aged 〈 50years （43.5±5.5 years）. The RFCA complication rate did not vary between groups. No differences in procedural characteristics were seenafter being analyzed by type of AF. Among patients with paroxysmal AF, 71.4% octogenarian vs. 84.7% young patients was free of anyarrhythmia, without AAs, after single procedure. For non-paroxysmal AF, arrhythmia-free survival without AAs, was considerably lower（58.6% octogenarians vs. 81.2% younger patients, P = 0.023）. If AAs were used, arrhythmia-free survival for paroxysmal AF increased to90.5% and 92.1% in octogenarians and younger patients, respectively; and in non-paroxysmal AF it increased to 79.3% vs. 88.4%. ConclusionsRFCA is a safe and effective strategy to achieve normal sinus rhythm in a highly selected group of octogenarians. Paroxysmal AF ablation inoctogenarians has similar clinical effectiveness as that seen in much younger patients. Non-paroxysmal AF ablation has lower, but still rea-sonable clinical effectiveness.

关键词： Atrial fibrillation Catheter ablation Effectiveness Octogenarians Safety The elderly

The effect of neodymium substitution on the structural and magnetic properties of nickel ferrite

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Progress in Natural Science:Materials International 2015年第3期25卷 215-221页

作者： ?srafil ?abiko?lu Levent Paral? Ondrej Malina Petr Novak josef Kaslik jiri Tucek jiri Pechousek jakub Navarik Oldrich Schneeweiss Celal Bayar University Faculty of Arts&SciencesDepartment of Physics 45140 Muradiye Celal Bayar University Department of Electronics and Automation Regional Centre of Advanced Technologies and Materials Department of Experimental Physics and Physical ChemistryFaculty of SciencePalacky University Institute of Physics of Materials of the Academy of Sciences of the Czech Republic

Nickel ferrite Ni Fe2O4 is a typical soft magnetic ferrite with high electrical resistivity used as high frequency magnetic material. Neodymium(Nd3+) doped Ni Fe2O4 materials were fabricated using solid state reaction. The properties of the obtained material were investigated by X-Ray Diffraction(XRD), Scanning Electron Microscope(SEM), Fourier-Transform Infrared Spectroscopy(FT-IR), magnetic measurements on SQUID and M?ssbauer spectroscopy. It was found that the material consists of two different phases: Nd3+doped Ni Fet2O4and Nd Fe O3. The Nd3 ions occupy cation sites of the Ni Fe2O4 inverse spinel structure. NdFeO3 phase occurred when the level of Nd3+atoms exceed a percolation *** presence of both phases was confirmed by SEM observations. The M?ssbauer spectra analysis showed two sextets, which can be ascribed to iron atoms in tetrahedral and octahedral positions. From their intensities it is concluded that Nd3+occupies octahedral sites in the spinel structure of Ni Fe2O4, which were originally occupied by Ni2+.

关键词： NiFe2O4 Neodymium Solid-state reaction Magnetic properties M?ssbauer spectroscopy