26 research outputs found

    Fossils as Key Resources of Hydrocarbons for the Chemical Industry - The Burning Problem of Industrial Development

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    Intensive research is being pursued world-wide to establish a methodology for industrial development. Many types of changes play an important role in the dynamics of the industrial structure in both large and small economies. The global energy supply and future substitution of crude oil are among the most important and widely investigated constraints. With the existing patterns of production and development strongly determined by the specific conditions in a given region, the development of various raw materials for the chemical industry is of great importance. The impact of changing production methods in feedstock hydrocarbons on industrial development requires further intensive research. A non-uniform demand vector and a variety of possible production processes, with a constrained supply of resources in different economic regions and countries, open a number of possibilities for new and non-conventional solutions. Further, hydrocarbon synthesis for the chemical industry should be a high priority research goal, not only because of the scale of demand, but because of the properties of the substances themselves. Provided the problem of production of hydrocarbon feedstock for the chemical industry can be solved successfully, the same methodology could also be used for the analysis of synfuel production: It would contribute to a better understanding of the dynamics of the industrial structure

    Alternative Routes from Fossil Resources to Chemical Feedstocks

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    The chemical industry depends very heavily on hydrocarbon feedstocks, which are presently derived almost exclusively from crude oil. Although only about seven percent of the hydrocarbons suitable for chemical processing are actually used in this way, it is already clear that there is a potential conflict between the needs of the energy sector and those of the chemical industry: they are competing for increasingly scarce liquid hydrocarbon resources. The authors suggest that the supply of hydrocarbon feedstocks to the chemical industry could be protected against the effects of changing patterns of energy use by modifying the underlying industrial structure. They have developed an approach which takes a variety of production processes (either in use or under development), compares their efficiency their consumption of different resources, etc., and finds the combination of technologies that best satisfies a particular demand while staying within the limits imposed by resource availability. This approach uses the techniques of interactive decision analysis to incorporate the unquantifiable social and political factors that must influence any development decision. By way of illustration, the method is applied to one very small part of the problem area: the different routes to the production of methanol. This report does not attempt to provide any final answer to the problem of feedstock supply, but rather to explain one possible approach to the problem and discuss some intermediate results. It is addressed not only to researchers, but also, and in particular, to all decision makers and industrial consultants facing problems of this type

    Generating Efficient Alternatives for Development in the Chemical Industry

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    Industrial development can be seen as the process of changing the production structure by means of investment over the course of time. To control this development to the benefit of society while maintaining the profitability of the industry, decision makers must learn how socioeconomic changes and market conditions affect the static and dynamic properties of the production structure. This paper reports on the progress of collaborative research into the design of tools which could help decision makers to control development in the chemical industry. The basic approach is to formulate a model of the equilibrium state of the industry or, in the case considered here, of a particular subsector of the industry. The development process is initially described by a static multiobjective optimization problem, from which a dynamic multiobjective optimization problem is then derived. An example illustrating the use of this method for the pesticide-producing sector is given. The optimization problem and method for controlling industrial development put forward in this paper were worked out as part of the research program on Growth Strategy Optimization Systems (GSOS), sponsored by the Ministry of the Chemical Industry in Poland. This program is actually carried out at the Institute for Control and Systems Engineering (ICSE), part of the Academy of Mining and Metallurgy (AMM) in Cracow. The multiobjective optimization method for generating efficient alternatives and the related software were developed by the System and Decision Sciences Area at IIASA. This collaborative research was carried out within the framework of the agreement on scientific cooperation cosigned by IIASA and the AMM in June 1980

    Mass calibration of DES Year-3 clusters via SPT-3G CMB cluster lensing

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    We measure the stacked lensing signal in the direction of galaxy clusters in the Dark Energy Survey Year 3 (DES Y3) redMaPPer sample, using cosmic microwave background (CMB) temperature data from SPT-3G, the third-generation CMB camera on the South Pole Telescope (SPT). Here, we estimate the lensing signal using temperature maps constructed from the initial 2 years of data from the SPT-3G 'Main' survey, covering 1500 deg2 of the Southern sky. We then use this lensing signal as a proxy for the mean cluster mass of the DES sample. The thermal Sunyaev-Zel'dovich (tSZ) signal, which can contaminate the lensing signal if not addressed, is isolated and removed from the data before obtaining the mass measurement. In this work, we employ three versions of the redMaPPer catalogue: a Flux-Limited sample containing 8865 clusters, a Volume-Limited sample with 5391 clusters, and a Volume&Redshift-Limited sample with 4450 clusters. For the three samples, we detect the CMB lensing signal at a significance of 12.4σ, 10.5σ and 10.2σ and find the mean cluster masses to be M 200m = 1.66±0.13 [stat.]± 0.03 [sys.], 1.97±0.18 [stat.]± 0.05 [sys.], and 2.11±0.20 [stat.]± 0.05 [sys.]×1014 M⊙, respectively. This is a factor of ∼ 2 improvement relative to the precision of measurements with previous generations of SPT surveys and the most constraining cluster mass measurements using CMB cluster lensing to date. Overall, we find no significant tensions between our results and masses given by redMaPPer mass-richness scaling relations of previous works, which were calibrated using CMB cluster lensing, optical weak lensing, and velocity dispersion measurements from various combinations of DES, SDSS and Planck data. We then divide our sample into 3 redshift and 3 richness bins, finding no significant discrepancies with optical weak-lensing calibrated masses in these bins. We forecast a 5.7% constraint on the mean cluster mass of the DES Y3 sample with the complete SPT-3G surveys when using both temperature and polarization data and including an additional ∼ 1400 deg2 of observations from the 'Extended' SPT-3G survey

    Physics research on the TCV tokamak facility: from conventional to alternative scenarios and beyond

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    The research program of the TCV tokamak ranges from conventional to advanced-tokamak scenarios and alternative divertor configurations, to exploratory plasmas driven by theoretical insight, exploiting the device’s unique shaping capabilities. Disruption avoidance by real-time locked mode prevention or unlocking with electron-cyclotron resonance heating (ECRH) was thoroughly documented, using magnetic and radiation triggers. Runaway generation with high-Z noble-gas injection and runaway dissipation by subsequent Ne or Ar injection were studied for model validation. The new 1 MW neutral beam injector has expanded the parameter range, now encompassing ELMy H-modes in an ITER-like shape and nearly non-inductive H-mode discharges sustained by electron cyclotron and neutral beam current drive. In the H-mode, the pedestal pressure increases modestly with nitrogen seeding while fueling moves the density pedestal outwards, but the plasma stored energy is largely uncorrelated to either seeding or fueling. High fueling at high triangularity is key to accessing the attractive small edge-localized mode (type-II) regime. Turbulence is reduced in the core at negative triangularity, consistent with increased confinement and in accord with global gyrokinetic simulations. The geodesic acoustic mode, possibly coupled with avalanche events, has been linked with particle flow to the wall in diverted plasmas. Detachment, scrape-off layer transport, and turbulence were studied in L- and H-modes in both standard and alternative configurations (snowflake, super-X, and beyond). The detachment process is caused by power ‘starvation’ reducing the ionization source, with volume recombination playing only a minor role. Partial detachment in the H-mode is obtained with impurity seeding and has shown little dependence on flux expansion in standard single-null geometry. In the attached L-mode phase, increasing the outer connection length reduces the in–out heat-flow asymmetry. A doublet plasma, featuring an internal X-point, was achieved successfully, and a transport barrier was observed in the mantle just outside the internal separatrix. In the near future variable-configuration baffles and possibly divertor pumping will be introduced to investigate the effect of divertor closure on exhaust and performance, and 3.5 MW ECRH and 1 MW neutral beam injection heating will be added

    Overview of the TCV tokamak experimental programme

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    The tokamak à configuration variable (TCV) continues to leverage its unique shaping capabilities, flexible heating systems and modern control system to address critical issues in preparation for ITER and a fusion power plant. For the 2019–20 campaign its configurational flexibility has been enhanced with the installation of removable divertor gas baffles, its diagnostic capabilities with an extensive set of upgrades and its heating systems with new dual frequency gyrotrons. The gas baffles reduce coupling between the divertor and the main chamber and allow for detailed investigations on the role of fuelling in general and, together with upgraded boundary diagnostics, test divertor and edge models in particular. The increased heating capabilities broaden the operational regime to include Te/Ti ∼ 1 and have stimulated refocussing studies from L-mode to H-mode across a range of research topics. ITER baseline parameters were reached in type-I ELMy H-modes and alternative regimes with \u27small\u27 (or no) ELMs explored. Most prominently, negative triangularity was investigated in detail and confirmed as an attractive scenario with H-mode level core confinement but an L-mode edge. Emphasis was also placed on control, where an increased number of observers, actuators and control solutions became available and are now integrated into a generic control framework as will be needed in future devices. The quantity and quality of results of the 2019–20 TCV campaign are a testament to its successful integration within the European research effort alongside a vibrant domestic programme and international collaborations.</p

    A Measurement of the CMB Temperature Power Spectrum and Constraints on Cosmology from the SPT-3G 2018 TT/TE/EE Data Set

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    We present a sample-variance-limited measurement of the temperature power spectrum (TTTT) of the cosmic microwave background (CMB) using observations of a  ⁣1500deg2\sim\! 1500 \,\mathrm{deg}^2 field made by SPT-3G in 2018. We report multifrequency power spectrum measurements at 95, 150, and 220GHz covering the angular multipole range 750<3000750 \leq \ell < 3000. We combine this TTTT measurement with the published polarization power spectrum measurements from the 2018 observing season and update their associated covariance matrix to complete the SPT-3G 2018 TT/TE/EETT/TE/EE data set. This is the first analysis to present cosmological constraints from SPT TTTT, TETE, and EEEE power spectrum measurements jointly. We blind the cosmological results and subject the data set to a series of consistency tests at the power spectrum and parameter level. We find excellent agreement between frequencies and spectrum types and our results are robust to the modeling of astrophysical foregrounds. We report results for Λ\LambdaCDM and a series of extensions, drawing on the following parameters: the amplitude of the gravitational lensing effect on primary power spectra ALA_\mathrm{L}, the effective number of neutrino species NeffN_{\mathrm{eff}}, the primordial helium abundance YPY_{\mathrm{P}}, and the baryon clumping factor due to primordial magnetic fields bb. We find that the SPT-3G 2018 T/TE/EET/TE/EE data are well fit by Λ\LambdaCDM with a probability-to-exceed of 15%15\%. For Λ\LambdaCDM, we constrain the expansion rate today to H0=68.3±1.5kms1Mpc1H_0 = 68.3 \pm 1.5\,\mathrm{km\,s^{-1}\,Mpc^{-1}} and the combined structure growth parameter to S8=0.797±0.042S_8 = 0.797 \pm 0.042. The SPT-based results are effectively independent of Planck, and the cosmological parameter constraints from either data set are within <1σ<1\,\sigma of each other. (abridged
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