• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 224
  • 31
  • 19
  • 18
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 329
  • 329
  • 218
  • 178
  • 178
  • 108
  • 38
  • 23
  • 22
  • 21
  • 18
  • 17
  • 17
  • 17
  • 17
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

On the design of chemical processes with improved controllability characteristics

Meeuse, F. Michiel. January 1900 (has links)
Thesis (doctoral)--Technische Universiteit Delft, 2003. / Includes bibliographical references (p. 153-162).
22

MIMO control performance monitoring based on subspace projections

McNabb, Christopher Alan. January 2002 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.
23

Operability characteristics of reacting systems /

Subramanian, Sivakumar, January 2002 (has links)
Thesis (Ph. D.)--Lehigh University, 2002. / Includes vita. Includes bibliographical references (leaves 143-152).
24

Cyclically optimized electrochemical processes /

Ruedisueli, Robert Louis. January 1997 (has links)
Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [124]-136).
25

Studies in optimizing and regulatory control of chemical processing systems

Garcia, Carlos Enrique. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 269-277).
26

Integrated design of chemical plants with energy conservation (the design of an energy efficient styrene plant)

Saeed, Auday Esmail January 1990 (has links)
Energy consumption is one of the main areas in the study of chemical process design. It is usually referred to as the critical element that is continuously needed for running a chemical process, and is daily effected by the prices of energy. Therefore, poor designs which are not energy integrated normally lead to less profit due to high consumption of energy. These simple economics are the reason for tackling the area of energy integration in process design. A styrene production process is taken to be the model process for carrying out the design work incorporating the various energy integration techniques. A thorough review of the published work in this subject area was the first step in this research work. This has been followed by calculating mass and energy balances around the overall plant and the individual process steps, so that information about flowrates and energy consumed and released was obtained for the base case. After this all the possible distillation sequence configurations were tested in order to find the sequence that required least energy compared with all the other possible sequences. This step is the first part of integrating the distillation train. The second part considered the heat exchanger network associated with the distillation train and this has been taken in the context of overall process integration. "Pinch technology" was used as an aid for targeting the minimum hot and cold utilities required, designing the heat exchanger network that was compatible with the minimum use of utility and to seek further improvements on the process heat exchanger network which made it capable of recovering even more energy. Utility supplies are designed with respect to the process design, hence the next step considered the interaction between the utility and process design. Thus, the utilities were introduced in a more efficient way, resulting in a better heat exchanger network and increasing the interprocess heat exchange. Finally the steam and power system in the styrene plant was tested in order to determine how much this system had benefited due to the overall efficiency of energy supply and demand.
27

The design and evaluation of a digital controller /

Curran, Michael Anthony January 1974 (has links)
No description available.
28

A study of the modelling, dynamic simulation and control of the modern fluid catalytic cracking process

Illes-Smith, Peter C. January 1985 (has links)
No description available.
29

Effect of filtration aid on downstream processing of polymer particles : Effektivisering av avvattningsprocessen av polymerpartiklar

Johansson, Emma January 2019 (has links)
Polymer particles are expandable and produced by Nouryon. The production consists of polymerization, dewatering and drying. Dewatering of polymer particlesis an important part of the production process and have a large impact on how efficient the downstream process can be performed. An efficient dewatering enablesa fast and effective drying process and is therefore of great importance for a fastproduction process. Here, today, there are big variations. For mostpolymer particlegradesthe dewatering aid DEW1is added to the slurry. DEW1is a non-ionic surfactant that greatly increases dewatering abilities of slurry and thus increases speedof the downstream process. But, DEW1cannotbeused for allpolymer particlegrades due to regulations. Therefore, thosepolymer particlesdemand longer downstream times with higher production costs and higher energy consumption following. The aim ofthisdiploma work was to find an alternative dewatering aid which can be used for all polymer particle grades, has a good environmental profile and increases speed of the drying process. Several compounds weretestedin laboratory scaleduring this studyto investigatetheir effect ondry contentafter dewatering.One ofthem, DEW2, showedpromising features as an alternativedewatering aid which isalso bio-based. The highestdry content ofdewatered polymer particleslurrywith DEW2as dewatering aidwasXwt% dry polymer particles.This was2.2wt% higher dry content thanthe results achieved with DEW1.Also, the effect of heated polymer particleslurry and wash water on dry content wasinvestigatedduring this study. A strong relation between higher temperatures of especially wash water and increased dry content of dewatered polymer particleswasdetected. The highest dry content achieved was Xwt% dry polymer particlesfrom a test with slurry 20 °Cand wash water 80 °C. This was an increase in dry content with 26.9 % compared to the lowest dry content achieved. The lowest value was obtained when both slurry and wash water temperature was 20 °C, which during these tests gave a dry content of Xwt%. However, polymer particlesfrom testswith high temperatures showed signs of agglomerationof polymer particles on dispersion testwhich is not accepted for polymer particles of good quality.Two full scale production trialswere performed with wash water heated to 40 °C. No agglomerated polymer particleswereseen in the dried product, and the production speed increased with 18 respectively 11 % / Polymerpartiklar är expanderbara och producerade av Nouryon. Produktionen består av polymerisation, avvattning samt torkning.Avvattning avpolymerpartikelslurry är en stordel av efterbehandlingsprocessenoch det är viktigt att den kan genomföras effektivtför att minska tids-och energiåtgång. En väl fungerande avvattning främjar en snabb och effektiv torkprocess och är därför av stor betydelse för en snabb produktionsprocess. Idag finns stora variationergällande tidsåtgång beroende påvilken polymerpartikelskvalitet som produceras. Till de flesta polymerpartikelskvalitetertillsättsDEW1som fungerar somavvattningshjälpmedel. DEW1är en non-jonisk tensid som avsevärt förbättrar avvattningskapacitetenför polymerpartikelslurrynoch därmed förkortar efterbehandlingstidenoch därmed den totala produktionstiden. Dock kan inte DEW1användas föralla typer av polymerpartiklar.Det medför att produktionstidenförlängsför dessa kvaliteter, vilketleder till högre produktionskostnader samt en högre energiförbrukning. Syftet med det här examensarbetet varatt hitta ett alternativt avvattningshjälpmedelsom är miljövänligt,ökarhastigheten på avvattning-och torkningsprocessenoch som kan användas för alla typer av polymerpartiklar. Ett antal substansertestadesunder examensarbetet laborativt för att utvärdera deras effekt påtorrhalt på polymerpartiklarefter avvattning. Det biobaseradeavvattningshjälpmedlet DEW2såglovande ut med goda avvattningsegenskaper. Resultaten från försök med DEW2gav2.2wt% högre torrhaltän DEW1. Andra försök gjordes under examensarbetetför att undersöka sambandet mellan temperatur på polymerpartikelslurryoch tvättvatten mot torrhalt på avvattnade polymerpartiklar. Högre temperatur på speciellt tvättvatten gavhögre torrhalt, och den högsta torrhalten som uppnåddes vid försöken varXwt%med en slurrytemperatur på 20 °Coch tvättvattentemperatur på80 °C.Jämfört med det sämsta resultatet för torrhalt var det en ökningmed26.9%mot resultatet från tester utförda med slurry och tvättvattentemperatur 20 °C, som gav torrhalten Xwt%. Dessvärre visadedispersionstesterfrån testerutförda med temperaturer mellan 50 till 80 °Catt agglomerat bildatsi torkade polymerpartiklar.Två produktionstester utfördes där tvättvattnet värmdes till 40 °C. Här sågs inga problem med agglomerat i färdig produktoch produktionshastigheten ökade med 18 respektive 11 %.
30

Dynamic data reconciliation using process simulation software and model identification tools

Alici, Semra 14 March 2011 (has links)
Not available / text

Page generated in 0.0886 seconds