21 resultados para GTL


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Although the production of liquid fuels from coal, natural gas (CTL and GTL processes) and other carbon sources has been discovered 90 years ago, the interest was renewed in the last years motivated by stranded gas reserves and by petroleum market instability. This review intends to show the scenario of these technologies nowadays, discussing the applied technologies, the steps in an industrial plant, the ways to produce syngas and liquid fuels, the catalysts used, the type of reactors and the operating plants with their respective capacities, besides the technical, economical and environmental viability, challenges and perspectives for Brazil.

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With growing demand for liquefied natural gas (LNG) and liquid transportation fuels, and concerns about climate change and causes of greenhouse gas emissions, this master’s thesis introduces a new value chain design for LNG and transportation fuels and respective fundamental business cases based on hybrid PV-Wind power plants. The value chains are composed of renewable electricity (RE) converted by power-to-gas (PtG), gas-to-liquids (GtL) or power-to-liquids (PtL) facilities into SNG (which is finally liquefied into LNG) or synthetic liquid fuels, mainly diesel, respectively. The RE-LNG or RE-diesel are drop-in fuels to the current energy system and can be traded everywhere in the world. The calculations for the hybrid PV-Wind power plants, electrolysis, methanation (H2tSNG), hydrogen-to-liquids (H2tL), GtL and LNG value chain are performed based on both annual full load hours (FLh) and hourly analysis. Results show that the proposed RE-LNG produced in Patagonia, as the study case, is competitive with conventional LNG in Japan for crude oil prices within a minimum price range of about 87 - 145 USD/barrel (20 – 26 USD/MBtu of LNG production cost) and the proposed RE-diesel is competitive with conventional diesel in the European Union (EU) for crude oil prices within a minimum price range of about 79 - 135 USD/barrel (0.44 – 0.75 €/l of diesel production cost), depending on the chosen specific value chain and assumptions for cost of capital, available oxygen sales and CO2 emission costs. RE-LNG or RE-diesel could become competitive with conventional fuels from an economic perspective, while removing environmental concerns. The RE-PtX value chain needs to be located at the best complementing solar and wind sites in the world combined with a de-risking strategy. This could be an opportunity for many countries to satisfy their fuel demand locally. It is also a specific business case for countries with excellent solar and wind resources to export carbon-neutral hydrocarbons, when the decrease in production cost is considerably more than the shipping cost. This is a unique opportunity to export carbon-neutral hydrocarbons around the world where the environmental limitations on conventional hydrocarbons are getting tighter.

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Biomass Refinery is a sequential of eleven thermochemical processes and one biological process with two initial basic treatments: prehydrolysis for lignocellulosics and low temperature conversion for biomass with medium-to-high content of lipids and proteins. The other ten processes are: effluent treatment plant, furfural plant, biodiesel plant, cellulignin dryer, calcination, fluidized bed boiler, authotermal reforming of cellulignin for syngas production, combined cycle of two-stroke low-speed engine or syngas turbine with fluidized bed boiler heat recovery, GTL technologies and ethanol from cellulose, prehydrolysate and syngas. Any kind of biomass such as wood, agricultural residues, municipal solid waste, seeds, cakes, sludges, excrements and used tires can be processed at the Biomass Refinery. Twelve basic products are generated such as cellulignin, animal feed, electric energy, fuels (ethanol, crude oil, biodiesel, char), petrochemical substitutes, some materials (ash, gypsum, fertilizers, silica, carbon black) and hydrogen. The technology is clean with recovery of energy and reuse of water, acid and effluents. Based on a holistic integration of various disciplines Biomass Refinery maximizes the simultaneous production of food, electric energy, liquid fuels and chemical products and some materials, achieving a competitive position with conventional and fossil fuel technologies, as well as payment capacity for biomass production. Biomass Refinery has a technical economical capability to complement the depletion of the conventional petroleum sources and to capture its GHGs resulting a biomass + petroleum ""green"" combination.

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Introducció: El bypass gàstric en Y de Roux laparoscòpic (BGYRL) és la tècnica quirúrgica d’elecció per al tractament de l’obesitat mòrbida. La gastrectomia tubular laparoscòpica (GTL) és una tècnica bariàtrica restrictiva amb resultats molt prometedors en relació a la pèrdua de pes, però se’n desconeixen els efectes metabòlics i endocrins. L’objectiu d’aquest estudi és l’avaluació de les diferències en la resposta del metabolisme de la glucosa i la secreció d’hormones intestinals entre ambdós procediments. Material i mètodes: Es va dissenyar un estudi prospectiu i aleatoritzat per la realització del BGYRL i la GTL, ambdós realitzats via laparoscòpica. Totes les pacients es varen avaluar abans, i als 3 i 12 mesos de la intervenció. Se’ls va prendre una mostra de sang venosa després d’un dejuni de 12 hores i als 10 i 60 minuts després de la ingesta d’Ensure® 420 kcal per realitzar les determinacions dels nivells plasmàtics de glucosa, insulina, grelina, leptina, pèptid relacionat amb glucagó (GLP-1), pèptid YY (PYY) i polipèptid pancreàtic (PP). Resultats: Es varen incloure 15 pacients (totes de gènere femení, edat mitja de 48±9 anys, IMC de 44±2.7 kg/m2 amlitat preoperatòria) dels quals 7 van ser aleatoritzats a BGYRL i 8 a GTL. No hi van haver diferències entre ambdós grups en edat, IMC preoperatori, classificació ASA i determinacions hormonals preoperatòries. Després de la cirurgia, s’observa un descens de la glicèmia i insulinèmia, amb una reducció de l´índex HOMA-IR en ambdós grups. Postoperatòriament, es detecta una disminución de les concentracions de la leptina en dejú i després de la ingesta, significativament menor en el grup de BGYRL. Mentre que els nivells de grelina en dejú només descendeixen de forma significativa en el grup de la GTL. Després de la ingesta es produeix una augment dels nivells de GLP-1, significativament major en el grup de BGYRL. Conclusions: Tan el BGYRL como la GTL s’associen a una significativa pèrdua de pes, encara que aquesta fou significativament superior en el BGYRL. Ambdós procediments han millorat notablement l’homeostasi de la glucosa. Només la GTL va rehuir els nivells de grelina tan en dejú com després de la ingesta, mentre que els nivells de GLP-1 i PYY s’elevaren després de la cirurgia, sense diferències estadísticament significatives entre ambdues tècniques.

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Co/Al(2)O(3) Fischer-Tropsch synthesis catalysts promoted with different quantities of Group 11 metals (Cu, Ag, Au) were characterized and tested. The presence of relatively small quantities of such metals enhanced Co reducibility and, in the cases of Ag and Au, improved the surface Co metal active site densities. EXAFS experiments with the most loaded catalyst samples show that only Co-Co and Me-Me (Me = Cu, Ag and Au) coordination could be observed. This suggests that the greater fraction of the metals form different phases. However, the reduction promoting effect of the Group 11 metal is severely hampered once the catalyst receives a mild passivation treatment following primary reduction. An explanation in terms of promoter segregation during primary reduction is proposed. At lower promoter levels (0.83%Ag and 1.51%Au) and higher Ag levels (2.76%), significant gains in Co active site densities were achieved resulting in improved CO conversion levels relative to the unpromoted catalyst. Moreover, slight decreases in light product (e.g., CH(4)) selectivity and slight increases in C(5)+ selectivity were achieved. At high Au loading (5.05%), however, too much Au was loaded which, although significantly increasing the fraction of Co reduced, blocked Co surface sites and resulted in decreased Co conversion rates. While Cu facilitated Co reduction, the increased fraction of reduced Co did not translate to improved active site densities. It appears that a fraction of Cu tended to cover the rim of Co clusters, resulting in decreases in CO conversion rates and detrimental increases in light product selectivity. (C) 2009 Elsevier B.V. All rights reserved.

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The current natural gas production of 52 Mm3d-1 and the large projects for its expansion has been setting new boundaries for the Brazilian industry of oil and gas. So far, one of the biggest challenges regards to the logistics for gas transportation from offshore fields. Therefore, the transformation of natural gas into gasoline, diesel and/or olefins via Fischer-Tropsch synthesis would be an alternative to this matter. In this work, the production of hydrocarbons by Fischer-Tropsch synthesis in a slurry reactor was investigated and a perovskite-type catalyst (LayCu0,4Fe0,6O3 ± d) was used with y varying from 0 to 1 on a molar basis. In addition, Nb2O5 support was also applied in order to observe the selectivity of the produced hydrocarbons by the Fischer-Tropsch process. It is shown that the hydrogen conversion was influenced by the support as well as the different phases of the samples. The kinetic results for the CO2 production suffered great influence with the introduction of the Nb2O5 support throughout the series of samples studied. The catalysts allowed obtaining welldefined cuts of hydrocarbons in the range of C1-C6 and C17-C28, and these results were clearly influenced by the support and the lanthanum content. The higher olefin/paraffin ratio obtained was 1.8 when using a non-supported perovskite with y equal to 0.8. This would indicate the suitability of using this material for the production of olefins

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The research of new advanced processes for syngas production is a part of a European project for the production of a new Gas to Liquid Process (NextGTL). The crucial points in the production of GTL process are the energy required for the air separation used in autothermal reforming or the heat required for steam reforming and the efficiency in carbon utilization. Therefore a new multistep oxy-reforming process scheme was developed at lower temperature with intermediate H2 membrane separation to improve the crucial parameter. The process is characterized by a S/C of 0.7 and O2/C of 0.21 having a smoothed temperature profile in which kinetic regime is easily obtained. Active catalysts for low temperature oxy-reforming process have been studied working at low pressure to discriminate among the catalyst and at high pressure to prove it on industrial condition. It allows the selection of the Rh as active phase among single and bimetallic VIII group metal. The study of the matrix composition and thermal treatment has been carried out on Rh-Mg/Al hydrotalcite selected as reference catalyst. The research to optimize the catalyst lead to enhanced performances through the identification of a limitation of the Rh reduction from the oxides matrix as key point to increase the Rh performances. The Rh loading have been studied to allow the catalyst scale up for pilot process in Chieti in a shape of Rh-HT on honeycomb ceramic material. The developed catalyst has enhanced methane conversion in a inch diameter monolith reactor if compared with the semi-industrial catalyst chosen in the project as the best reference.

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MET, also known as hepatocyte growth factor receptor (HGFR), is a receptor tyrosine kinase with an important role, both in normal cellular function as well as in oncogenesis. In many cancer types, abnormal activation of MET is related to poor prognosis and various strategies to inhibit its function, including small molecule inhibitors, are currently in preclinical and clinical evaluation. Autophagy, a self-digesting recycling mechanism with cytoprotective functions, is induced by cellular stress. This process is also induced upon cytotoxic drug treatment of cancer cells and partially allows these cells to escape cell death. Thus, since autophagy protects different tumor cells from chemotherapy-induced cell death, current clinical trials aim at combining autophagy inhibitors with different cancer treatments. We found that in a gastric adenocarcinoma cell line GTL-16, where MET activity is deregulated due to receptor overexpression, two different MET inhibitors PHA665752 and EMD1214063 lead to cell death paralleled by the induction of autophagy. A combined treatment of MET inhibitors together with the autophagy inhibitor 3-MA or genetically impairing autophagy by knocking down the key autophagy gene ATG7 further decreased cell viability of gastric cancer cells. In general, we observed the induction of cytoprotective autophagy in MET expressing cells upon MET inhibition and a combination of MET and autophagy inhibition resulted in significantly decreased cell viability in gastric cancer cells.

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An approach was developed for the quantification of subtle gains and losses of genomic DNA. The approach relies on a process called molecular combing. Molecular combing consists of the extension and alignment of purified molecules of genomic DNA on a glass coverslip. It has the advantage that a large number of genomes can be combed per coverslip, which allows for a statistically adequate number of measurements to be made on the combed DNA. Consequently, a high-resolution approach to mapping and quantifying genomic alterations is possible. The approach consists of applying fluorescence hybridization to the combed DNA by using probes to identify the amplified region. Measurements then are made on the linear hybridization signals to ascertain the region's exact size. The reliability of the approach first was tested for low copy number amplifications by determining the copy number of chromosome 21 in a normal and trisomy 21 cell line. It then was tested for high copy number amplifications by quantifying the copy number of an oncogene amplified in the tumor cell line GTL-16. These results demonstrate that a wide range of amplifications can be accurately and reliably quantified. The sensitivity and resolution of the approach likewise was assessed by determining the copy number of a single allele (160 kb) alteration.

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Poster presented in the 11th Mediterranean Congress of Chemical Engineering, Barcelona, October 21-24, 2008.

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Mode of access: Internet.

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Napjaink informatikai világának talán legkeresettebb hívó szava a cloud computing, vagy magyar fordításban, a számítási felhő. A fordítás forrása az EU-s (Digitális Menetrend magyar változata, 2010) A számítási felhő üzleti modelljének részletes leírását adja (Bőgel, 2009). Bőgel György ismerteti az új, közműszerű informatikai szolgáltatás kialakulását és gazdasági előnyeit, nagy jövőt jósolva a számítási felhőnek az üzleti modellek versenyében. A szerző – a számítási felhő üzleti előnyei mellett – nagyobb hangsúlyt fektet dolgozatában a gyors elterjedést gátló tényezőkre, és arra, hogy mit jelentenek az előnyök és a hátrányok egy üzleti, informatikai vagy megfelelőségi vezető számára. Nem csökkentve a cloud modell gazdasági jelentőségét, fontosnak tartja, hogy a problémákról és a kockázatokról is szóljon. Kiemeli, hogy a kockázatokban – különösen a biztonsági és adatvédelmi kockázatokban – lényeges különbségek vannak az Európai Gazdasági Térség és a világ többi része, pl. az Amerikai Egyesült Államok között. A cikkben rámutat ezekre a különbségekre, és az olvasó magyarázatot kap arra is, hogy miért várható a számítási felhő lassabb terjedése Európában, mint a világ más részein. Bemutatja az EU erőfeszítéseit is a számítási felhő európai terjedésének elősegítésére, tekintettel a modell versenyképességet növelő hatására. / === / One of the most popular concept of the recent web searches is cloud computing. Several authors present detailed description of the new service model and it's business benefits and cite the optimistic prognoses of the cloud experts regarding the competition of information system service models. The author analyses the operational benefits of the cloud application and give a detailed description of the inhibitors of the fast expansion of the service modell. He also analyses the pros and cons of the cloud for a business manager, an information and a compliance officer. When understanding the advantages of the cloud, it is equally important to review the problems and risks associated with the model. The paper gives a list of the expected cloud-specific risks. It also explains the differences in security and data protection approach between the European Economic Area and the rest of the world, including the USA. The explains why slower expansion of the cloud modell is expected in Europe than in the rest of the world. The efforts of the EU Committee in helping to spread the cloud model is also presented, as the EU's officers consider the model as an important element of competitiveness.

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Számos hazai kutatás foglalkozik az innováció alacsony szintjével a hazai vállalatoknál. Az innováció nemzetközi szakirodalma a fejlődés egyik fő tendenciájaként emeli ki a nyitott innováció (open innovation), a korai bevonás (early involvement) és a párhuzamos fejlesztés gyakorlatát. Ezek a megoldások (kutatásunk szempontjából közelítve a beszerzés és a beszállító bevonása az innováció korai szakaszába) hatékonyabbá teheti az innovációs folyamatot, mivel erőforrásokat vonhat be feloldva az innováció előtti akadályokat. Tanulmányunk a beszerzés szerepét elemzi az innovációban, igyekszik feltárni azokat a motivációs illetve gátló tényezőket, amelyek ezt a szerepet erősíthetik vagy gátolhatják. Vizsgálatunk kiterjed a vállalaton belüli és a beszállítói környezetre is. Vizsgáljuk azt az eszközrendszert is, amellyel a beszerzés az innováció támogatni, elősegíteni tudja. ____ Literature on innovation management highlight the role of early supplier involvement, open innovation and parallel model of innovation. Collaboration within the company and with suppliers is a common part of these concepts which makes innovation process more effective. This paper aims to investigate those factors that promotes and hinders the involvement of purchasing and suppliers into the innovations process. Based on literature review and interviews this paper aims to structure the supporting factors and applicable tools.

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A személy-környezet összeillés elméletei szerint az emberek viselkedésmintázata és a specifi kus környezeti feltételek között összefüggés áll fenn (Dúll, 1998). Ahogyan Gump (1990) rámutat, két ember hasonlóbban viselkedik egy adott helyen, mint ugyanazon ember két eltérő helyen. Brighem (1991) mindezt azzal magyarázza, hogy az egyén és a környezet között kialakuló interakció során illeszkedés alakul ki az egyén céljai és a környezet elrendezése között. A fi zikai környezet felépítése hatással van a társas interakciók kibontakozásának lehetőségére is, ezáltal befolyásolják az ott élők megküzdési stratégiáit (Evans et al., 1996, in: Dúll, 2009). Az interakciókat gátló helyek ennek megfelelően a személyek közötti kommunikáció hiányához, egymástól való elidegenedéshez vezethetnek. Az így kialakuló kollektív szemlélet hiánya számos, fenntarthatósági szempontból fontos viselkedés gátját képezheti (például javak megosztott igénybevétele, közösségi javak felelős használata). Mindez magyarázatul szolgálhat olyan esetekben is, ahol azt láthatjuk, hogy ugyanazon személy eltérő fogyasztási és viselkedési mintákat követ más-más helyszínen. Turisztikai szempontból azonban fontosabb annak vizsgálata, hogy egy adott desztináció milyen hatással van az odaérkező vendégek viselkedésére, módosítja-e azt, és ha igen, milyen irányba és miért.