Integrating commercial process simulators into engineering courses

Abstract: The aim of this article is to encourage university lecturers to utilize commercial process simulation software in engineering courses. This article provides examples on four different simulation modules which are implemented in chemical and electrical engineering courses at Oslo and Akershus University College. The students have given positive evaluation on the learning through the simulation exercises and considered the simulation tool easy to use. Together with the exam results the student feedback indicates enhanced learning outcom

Large-scale training simulators for industry and academia

How should industrial large-scale simulators be used in academia? Which aspects of industrial training can benefit engineering education? This article demonstrates the use of industrial large-scale simulators for educational and training purposes for both academia and industry. The didactic models of the simulator courses are described and the learning results are evaluated for two case examples using the same industrial oil and gas process simulator. The differences and similarities of the didactic models of the courses are explored and the further possibilities for collaboration between academia and industry are outlined

Novel modeling and control approach for performance improvement of an industrial copper solvent extraction process

More than 20% of the cathode copper is annually produced by copper leaching, solvent extraction and electrowinning processes. The focus in process technology has been on research and capital intensive development of the process equipment and chemicals. However, the financial benefits gained through an advanced control system would be significant. An advanced control system would maximize production by running the process closer to the optimal operating point, and increase the production of the first quality copper cathode by decreasing the variation in key process variables. The lack of adequate dynamic process models for industrial applications has, to date, prevented the development of advanced process control systems. Therefore, the first aim of this thesis is to develop dynamic models to describe the behaviour of an industrial copper solvent process and to facilitate control system development. The second aim of this thesis is to develop an advanced control system for the copper solvent extraction process, and to verify that the performance and profitability of an industrial copper solvent extraction process can be significantly increased by utilizing the advanced process control system. In the process model, the mass transfer of copper in the mixer-settler units is described by means of dynamic, modified ideal mixing and plug flow models. The equilibrium value for the ideal mixing model is calculated on the basis of the steady state McCabe-Thiele diagram. The model utilizes industrial online and offline measurements. The unit process models are combined according to the case plant flowsheet. Based on the process models, a control hierarchy is developed for the case copper solvent extraction process. The optimization level in the hierarchy consists of an optimization algorithm that maximizes the production of the copper solvent extraction process and provides setpoints for the stabilizing control level. The stabilizing control level consists of a single input-single output control strategy employing two PI controllers or, alternatively, a multi input-multi output control strategy using the model predictive control (MPC). The dynamic models are tested by comparing the simulated data with the industrial data. The controller performances are tested for setpoint tracking and disturbance rejection in the simulation environment with step input changes. The benefits of the control system are assessed by comparing the variation in the controlled variables and the total copper production to the data collected from the process under manual control. The dynamic models are tested with two data sets representing the normal operation of the industrial case copper solvent extraction plant. The models follow the output copper concentration trends smoothly for the major input changes in the flow rates and copper concentrations, and the residuals between the simulated data and the industrial measurements are sufficiently small. The average absolute error is 1-3 % of the mean value of the output copper concentrations. The performance of the control system for setpoint tracking and disturbance rejection is very good. As expected, the model predictive controller performs better than the PI controllers. The disturbance rejection capabilities are further improved by adding four feedforward compensators to the control strategies. Compared to manual control, the variation in the rich electrolyte copper concentration was decreased by 70-80 % with the PI controllers and 80-90 % with the model predictive controller. The copper mass production was increased by about 3-5 % with both control strategies. The modeling and control results are very encouraging for the further testing of the control system in an industrial copper solvent extraction plant.Katodikuparista vuosittain yli 20 % tuotetaan kuparin liuotus - uutto - elektrolyysi -menetelmällä. Prosessiteknologian painopisteenä on ollut prosessilaitteiden ja -kemikaalien kehittäminen, joka vaatii paljon tutkimusta ja runsaasti taloudellista pääomaa. Kehittyneitä säätömenetelmiä soveltamalla voitaisiin saavuttaa merkittäviä taloudellisia hyötyjä kuluttamalla huomattavasti vähemmän resursseja. Kehittyneellä säätöjärjestelmällä kuparin uuttoprosessin tuotantoa sekä parhaan katodilaadun osuutta koko tuotannosta voidaan kasvatettaa, koska prosessia voidaan ajaa lähempänä optimaalista operointipistettä ja prosessin laatuparametrien vaihtelua voidaan pienentää. Kuparin uuttoprosessille soveltuvien dynaamisten mallien puute on tähän mennessä estänyt ylemmän tason säätöjärjestemien kehityksen. Tämän työn ensimmäinen tavoite oli kehitettää dynaaminen malli, joka kuvaa teollisen kuparin uuttoprosessin käyttäytymistä ja mahdollistaa säätöjärjestelmän kehityksen. Työn toisena tavoitteena oli kehittää säätöjärjestelmä ja todistaa että sen avulla kuparin uuttoprosessin tehokkuutta ja tuottavuutta voidaan merkittävästi parantaa. Dynaaminen prosessimalli perustuu kuparin massansiirrolle vesi- ja orgaanisen faasin välilla sekoitus-selkeytys-prosessilaitteissa. Sekoittimen malli perustuu modifioituun ideaalisekoitin malliin, jossa tasapaino lasketaan McCabe-Thiele diagrammista. Selkeyttimen malli perustuu tulppavirtaukseen. Prosessimalli laadittiin yhdistelemällä sekoitin-selkeytin-yksikkömalleja teollisen sovellusprosessin virtauskaavion mukaisesti. Tämän mallin perusteella implementoitiin prosessisimulaattori. Prosessimalliin perustuen prosessille kehitettiin säätöhierarkia, joka koostuu optimointitason optimointialgoritmista ja stabiloivan säädön tason yksikkösäätöstrategiasta (PI- ja myötäkytkentäsäätimet) tai monimuuttujasäätöstrategiasta (MPC-säädin). Dynaamisten malleilla saatua simulointidataa verrattiin teolliseen prosessidataan hyvin tuloksin. Simuloitu data seurasi kuparikonsentraatioiden ja virtausten vaihteluista johtuvia muutoksia ja keskimääräinen ero simuloidun ja oikean datan valilla oli noin 1-3% testatuissa kahdessa datajoukossa. Säätösysteemiä testattiin prosessisimulaattorilla, jonka sisääntuloina käytettiin prosessidataa. Manuaaliseen säätöön verrattuna, rikkaan elektrolyytin kuparikonsentraation vaihtelu pienentyi 70-80% PI-säätimillä ja 80-90% MPC-säätimellä. Kuparin tuotanto kasvoi 3-5% käyttämällä kumpaakin säätöstrategiaa. Mallitus- ja säätötulokset luovat vahvan pohjan säätösysteemin testaukselle teollisella kuparin uuttolaitoksella.reviewe

Economic benefits of training simulators

Use of operator training simulators (OTS) is claimed to be one of the best ways to train new operators and to refresh the skills of experienced ones, providing numerous benefits to the companies. What is the value of an operator training simulator in oil & gas industry? What are the economical and HSE benefits of successful simulator training? How much can be earned or saved by the use of training simulators? How large increase in productivity and effectiveness can be gained? This article reviews the OTS practices and quantifies the benefits of the OTS use based on a survey conducted in the Norwegian Oil & Gas industry during fall 2011

Randomized controlled trials in de-implementation research : a systematic scoping review

Background: Healthcare costs are rising, and a substantial proportion of medical care is of little value. De-implementation of low-value practices is important for improving overall health outcomes and reducing costs. We aimed to identify and synthesize randomized controlled trials (RCTs) on de-implementation interventions and to provide guidance to improve future research. Methods: MEDLINE and Scopus up to May 24, 2021, for individual and cluster RCTs comparing de-implementation interventions to usual care, another intervention, or placebo. We applied independent duplicate assessment of eligibility, study characteristics, outcomes, intervention categories, implementation theories, and risk of bias. Results: Of the 227 eligible trials, 145 (64%) were cluster randomized trials (median 24 clusters; median follow-up time 305 days), and 82 (36%) were individually randomized trials (median follow-up time 274 days). Of the trials, 118 (52%) were published after 2010, 149 (66%) were conducted in a primary care setting, 163 (72%) aimed to reduce the use of drug treatment, 194 (85%) measured the total volume of care, and 64 (28%) low-value care use as outcomes. Of the trials, 48 (21%) described a theoretical basis for the intervention, and 40 (18%) had the study tailored by context-specific factors. Of the de-implementation interventions, 193 (85%) were targeted at physicians, 115 (51%) tested educational sessions, and 152 (67%) multicomponent interventions. Missing data led to high risk of bias in 137 (60%) trials, followed by baseline imbalances in 99 (44%), and deficiencies in allocation concealment in 56 (25%). Conclusions: De-implementation trials were mainly conducted in primary care and typically aimed to reduce low-value drug treatments. Limitations of current de-implementation research may have led to unreliable effect estimates and decreased clinical applicability of studied de-implementation strategies. We identified potential research gaps, including de-implementation in secondary and tertiary care settings, and interventions targeted at other than physicians. Future trials could be improved by favoring simpler intervention designs, better control of potential confounders, larger number of clusters in cluster trials, considering context-specific factors when planning the intervention (tailoring), and using a theoretical basis in intervention design. Registration: OSF Open Science Framework hk4b2.Peer reviewe

Randomized controlled trials in de-implementation research : a systematic scoping review

Background: Healthcare costs are rising, and a substantial proportion of medical care is of little value. De-implementation of low-value practices is important for improving overall health outcomes and reducing costs. We aimed to identify and synthesize randomized controlled trials (RCTs) on de-implementation interventions and to provide guidance to improve future research. Methods: MEDLINE and Scopus up to May 24, 2021, for individual and cluster RCTs comparing de-implementation interventions to usual care, another intervention, or placebo. We applied independent duplicate assessment of eligibility, study characteristics, outcomes, intervention categories, implementation theories, and risk of bias. Results: Of the 227 eligible trials, 145 (64%) were cluster randomized trials (median 24 clusters; median follow-up time 305 days), and 82 (36%) were individually randomized trials (median follow-up time 274 days). Of the trials, 118 (52%) were published after 2010, 149 (66%) were conducted in a primary care setting, 163 (72%) aimed to reduce the use of drug treatment, 194 (85%) measured the total volume of care, and 64 (28%) low-value care use as outcomes. Of the trials, 48 (21%) described a theoretical basis for the intervention, and 40 (18%) had the study tailored by context-specific factors. Of the de-implementation interventions, 193 (85%) were targeted at physicians, 115 (51%) tested educational sessions, and 152 (67%) multicomponent interventions. Missing data led to high risk of bias in 137 (60%) trials, followed by baseline imbalances in 99 (44%), and deficiencies in allocation concealment in 56 (25%). Conclusions: De-implementation trials were mainly conducted in primary care and typically aimed to reduce low-value drug treatments. Limitations of current de-implementation research may have led to unreliable effect estimates and decreased clinical applicability of studied de-implementation strategies. We identified potential research gaps, including de-implementation in secondary and tertiary care settings, and interventions targeted at other than physicians. Future trials could be improved by favoring simpler intervention designs, better control of potential confounders, larger number of clusters in cluster trials, considering context-specific factors when planning the intervention (tailoring), and using a theoretical basis in intervention design. Registration: OSF Open Science Framework hk4b2.Peer reviewe

Effect of remdesivir post hospitalization for COVID-19 infection from the randomized SOLIDARITY Finland trial

We report the first long-term follow-up of a randomized trial (NCT04978259) addressing the effects of remdesivir on recovery (primary outcome) and other patient-important outcomes one year after hospitalization resulting from COVID-19. Of the 208 patients recruited from 11 Finnish hospitals, 198 survived, of whom 181 (92%) completed follow-up. At one year, self-reported recovery occurred in 85% in remdesivir and 86% in standard of care (SoC) (RR 0.94, 95% CI 0.47-1.90). We infer no convincing difference between remdesivir and SoC in quality of life or symptom outcomes (p > 0.05). Of the 21 potential long-COVID symptoms, patients reported moderate/major bother from fatigue (26%), joint pain (22%), and problems with memory (19%) and attention/concentration (18%). In conclusion, after a one-year follow-up of hospitalized patients, one in six reported they had not recovered well from COVID-19. Our results provide no convincing evidence of remdesivir benefit, but wide confidence intervals included possible benefit and harm.Peer reviewe

Integrating commercial process simulators into engineering courses

Abstract: The aim of this article is to encourage university lecturers to utilize commercial process simulation software in engineering courses. This article provides examples on four different simulation modules which are implemented in chemical and electrical engineering courses at Oslo and Akershus University College. The students have given positive evaluation on the learning through the simulation exercises and considered the simulation tool easy to use. Together with the exam results the student feedback indicates enhanced learning outcom

Constructive Assessment Method for Simulator Training

Industrial operator assessment is a very controversial subject in the scientific community, as determining the most suitable, objective and effective means of giving feedback on an operator’s performance is a great challenge. This paper presents a proposal on assessment methods for simulation training. The development is based on the results from simulator training courses held at Oslo and Akershus University College of Applied Sciences (HiOA) from 2010 to 2014. The results and course evaluation were analyzed to identify where new methods could be applied that would lead to improvement. The method proposed consists of an automatic assessment procedure, which will give feedback to the simulator course participants during the simulator session and help the students to achieve the learning outcomes. The proposed method will be tested in the simulator training courses at HiOA in spring 2017 and the results will be presented in a later paper