Carbon Brainprint Case Study: optimising defouling schedules for oil- refinerypreheat trains

In an oil refinery, crude oil is heated to 360-370°C before entering a distillation columnoperating at atmospheric pressure where the gas fraction and several liquid fractions withdifferent boiling points (e.g. gasoline, kerosene, diesel, gas oil, heavy gas oil) are separated off.The crude oil is heated in two stages. The preheat train - a series of heat exchangers - heats itfrom ambient temperature to about 270°C when it enters the furnace, known as the coil inlettemperature. The furnace then heats the oil to the temperature required for distillation.The purpose of the preheat train is to recover heat from the liquid products extracted in thedistillation column. Without this, 2-3% of the crude oil throughput would be used for heating thefurnace; with the preheat train up to 70% of the required heat is recovered. It also serves tocool the refined products: further cooling normally uses air or water. Over time, fouling reduces the performance of the heat exchangers, increasing the amount ofenergy that has to be supplied. It is possible to bypass units to allow them to be cleaned, withan associated cost and temporary loss of performance. The cleaning schedule thus has animpact on the overall efficiency, cost of operation and emissions. The group at the Department of Chemical Engineering and Biotechnology at Cambridgedeveloped a scheduling algorithm for this non-linear optimisation problem. It yields a good,though not-necessarily optimal, schedule and can handle additional constraints, such as thepresence of desalters with specific temperature requirements within the preheat train. This isnow being developed into a commercial software product. Data from two refineries - one operated by Repsol YPF in Argentina and the Esso FawleyRefinery in the UK - were used to model the systems and test the algorithm. For the Repsol YPF refinery, when compared with current practice and including a constrainton the desalter inlet temperature, the most conservative estimate of the emissions reductionwas 773 t CO2/year. This assumed a furnace efficiency of 90%. The emissions reductionincreased to 927 t CO2/year at 75% efficiency and 1730 t CO2/year at 40%. These were basedon a stoichiometric estimate of the emissions from the furnace. Using a standard emissionfactor increased them by 7.4%. For Esso Fawley, the estimated emission reduction compared to no maintenance was1435 t CO2/year at 90% furnace efficiency. This increased to 1725 t CO2/year at 75% and3225 t CO2/year at 40% efficien

Effects of cAMP on the composition of berry juice in Muscat Bailey A

In Muscat Bailey A, the increases of organic acids due to cAMP prebloom application 3 weeks before final harvest were accompanied by increases of glucose and fructose, though these increments compared with control diminished toward full maturity. Der Einfluß von cyclischem Adenosin-3' ,5' -monophosphat auf die Zusammensetzung des Beerensaftes bei Muscat Bailey A Wurden die Infloreszenzen der Rebsorte Muscat Bailey A (Vitis labrusca L. x V. vinifera L.) vor der Blüte mit cAMP behandelt, so war 3 Wochen vor der vollen Reife ein Anstieg des Säuregehaltes und ebenso der Glucose- und Fructosekonzentration zu verzeichnen; gegen Ende der Reifephase waren die Unterschiede im Glucose- und Fructosegehalt behandelter und unbehandelter Beeren allerdings ziemlich verwischt

Increase of the acid contents in grape berries by treatment with cAMP

cAMP prebloom application to flower clusters of the grapevine variety Delaware (Vitis labruscana BAILEY) raised the content of organic acids in the repening berries. The total content of amino acids in the juice was raised by postbloom application, alanine, arginine and γ-aminobutyric acid being increased, whereas tyrosine was decreased. Zunahme des Säuregehaltes reifender Traubenbeeren durch Behandlung mit cyclischemAdenosin-3',5' -monophosphat Bei der Rebsorte Delaware wurde durch Behandlung der Infloreszenzen mit cAMP vor der Blüte der Gehalt des Beerensaftes an organischen Säuren erhöht.Durch cAMP-Behandlung nach der Blüte wurde der Gesamtgehalt der Aminosäuren gesteigert, wobei Alanin, Arginin und γ-Aminobuttersäure zunahmen, während die Tyrosinkonzentration verringert war. &nbsp

Evaluation of 4 Outcomes Measures in Microtia Treatment: Exposures, Infections, Aesthetics, and Psychosocial Ramifications.

BackgroundIn craniofacial microsomia, microtia and canal atresia pose formidable reconstructive challenges. We review our institutional experience in treating microtia and atresia to identify variables associated with 4 outcomes measures: complications, surgical revisions, aesthetic outcomes, and psychosocial function.MethodsCraniofacial microsomia patients treated at the University of California Los Angeles Craniofacial Clinic between 2008 and 2014 greater than 13 years of age (n = 68) were reviewed for microtia and atresia treatment and outcomes.ResultsIn total, 91.2% of patients diagnosed with craniofacial microsomia presented with microtia, affecting 75 ears. Both a male and right-sided predominance were observed. Fifty-six patients (90.3%) underwent autologous external ear reconstruction at an average age of 8.5 years. Age, type of incision, and size of cartilage framework did not predict total number of surgeries or complications. Severity of ear anomalies correlated with increased number of surgeries (P < 0.001) and decreased aesthetic outcomes (P < 0.001) but not complications. In total, 87.1% of patients with microtia had documented hearing loss, of which the majority were conductive and 18.5% were mixed sensorineural and conductive. Hearing deficits were addressed in 70.4% of patients with external hearing aids, bone anchored hearing aids, or canaloplasty. Of all variables, improvement of psychosocial function was correlated only to hearing loss treatment of any type (P = 0.01).ConclusionsOn evaluation of surgical and patient characteristics, severity of microtia predicted the total number of surgical revisions performed and aesthetic ratings. In addition, we found that the only factor that correlated with improved patient and parent-reported psychosocial outcomes was treatment of hearing loss

Change of Electronic Structure Induced by Magnetic Transitions in CeBi

The temperature dependence of the electronic structure of CeBi arising from two types of antiferromagnetic transitions based on optical conductivity ($\sigma(\omega)$) was observed. The $\sigma(\omega)$ spectrum continuously and discontinuously changes at 25 and 11 K, respectively. Between these temperatures, two peaks in the spectrum rapidly shift to the opposite energy sides as the temperature changes. Through a comparison with the band calculation as well as with the theoretical $\sigma(\omega)$ spectrum, this peak shift was explained by the energy shift of the Bi $6p$ band due to the mixing effect between the Ce $4f \Gamma_8$ and Bi $6p$ states. The single-layer antiferromagnetic ($+-$) transition from the paramagnetic state was concluded to be of the second order. The marked changes in the $\sigma(\omega)$ spectrum at 11 K, however, indicated the change in the electronic structure was due to a first-order-like magnetic transition from a single-layer to a double-layer ($++--$) antiferromagnetic phase.Comment: 4 pages, to be published in J. Phys. Soc. Jpn. 73 Aug. (2004

Measurements of the Total Reaction Cross Section in 12C, 13C, 14N, 15N, 16O + 28Si Systems

開始ページ、終了ページ: 冊子体のページ付

Carbon brainprint - An estimate of the intellectual contribution of research institutions to reducing greenhouse gas emissions

This is the accepted manuscript of a paper published in Process Safety and Environmental Protection (Chatterton J, et al., Process Safety and Environmental Protection, 2015, 96, 74-81, doi:10.1016/j.psep.2015.04.008). The final version is available at http://dx.doi.org/10.1016/j.psep.2015.04.008Research and innovation have considerable, currently unquantified potential to reduce greenhouse gas emissions by, for example, increasing energy efficiency. Furthermore, the process of knowledge transfer in itself can have a significant impact on reducing emissions, by promoting awareness and behavioural change. The concept of the ‘carbon brainprint’ was proposed to convey the intellectual contribution of higher education institutions to the reduction of greenhouse gas emissions by other parties through research and teaching/training activities. This paper describes an investigation of the feasibility of quantifying the carbon brainprint, through six case studies. The potential brainprint of higher education institutes is shown to be significant: up to 500 kt CO2e/year for one project. The most difficult aspect is attributing the brainprint among multiple participants in joint projects.The Carbon Brainprint project was supported by the Higher Education Funding Council for England (HEFCE) under its Leading Sustainable Development in Higher Education programme, with support for case studies from Santander Universities. HEFCE, Research Councils UK and the Carbon Trust were members of the Steering Committee, which provided guidance, but did not direct the research. The Carbon Trust also advised on best practice in carbon footprinting. We are grateful to the many university staff at Cranfield, Cambridge and Reading Universities who shared their work with us so enthusiastically. We also thank the external partners and clients for the projects on which these case studies are based: Rolls-Royce plc, the ETI NOVA consortium, IGD, the Environment Agency, Esso, Repsol YPF, Carnego Systems Ltd. and Newera Controls Ltd