Potential for energy savings by heat recovery in an integrated steel supply chain

Heat recovery plays an important role in energy saving in the supply chain of steel products. Almost all high temperature outputs in the steel industry have their thermal energy exchanged to preheat inputs to the process. Despite the widespread development of heat recovery technologies within process stages (process heat recovery), larger savings may be obtained by using a wider integrated network of heat exchange across various processes along the supply chain (integrated heat recovery). Previous pinch analyses have been applied to optimise integrated heat recovery systems in steel plants, although a comparison between standard process heat recovery and integrated heat recovery has not yet been explored. In this paper, the potential for additional energy savings achieved by using integrated heat recovery is estimated for a typical integrated steel plant, using pinch analysis. Overall, process heat recovery saves approximately 1.8 GJ per tonne of hot rolled steel (GJ/t hrs), integrated heat recovery with conventional heat exchange could save 2.5 GJ/t hrs, and an alternative heat exchange that also recovers energy from hot steel could save 3.0 GJ/t hrs. In developing these networks, general heat recovery strategies are identified that may be applied more widely to all primary steel production to enhance heat recovery. Limited additional savings may be obtained from the integration of the steel supply chain with other industries.Dr. McBrien’s work on this paper was funded by EPSRC grant EP/G007217/1, and Dr. Serrenho and Professor Allwood were funded by EPSRC grant EP/N02351X/1.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.applthermaleng.2016.04.09

Scrap, carbon and cost savings from the adoption of flexible nested blanking

Steel accounts for 6% of anthropogenic CO2 emissions, most of which arises during steelmaking rather than downstream manufacturing. While improving efficiency in steelmaking has received a great deal of attention, improving material yield downstream can have a substantial impact and has received comparatively less attention. In this paper, we explore the conditions required for manufacturers to switch to a more materially efficient process, reducing demand for steel and thus reducing emissions without reducing the supply of goods to consumers. Furthermore, we present an alternative processing route where parts can be cut in flexible arrangements to take advantage of optimal nesting across multiple part geometries. For the first time, we determine the potential savings that flexible nested blanking of parts could achieve by calculating the potential for grouping orders with tolerably-similar thickness, strengths, ductility and corrosion-resistance. We found that 1,080 kt of CO2 and 710 kt of steel worth € 430M could be saved each year if this scheme was adopted across all European flat steel mills serving the automotive sector

The deformation of metal powder particles: Hardness and microstructure

© 2017 The Authors. Published by Elsevier Ltd. The modelling of powder densification requires knowledge about the material properties of the particles. Some models use the material properties of the material in bulk as inputs for modelling the densification of assemblies of powder particles. It is important to understand how these properties differ when the material is in powder form. Existing works tend to analyse bulk material or powder exclusively and rarely compare properties such as hardness between the two. This work compares the microstructures and hardness of metal powder with bulk material with the aim of guiding the assumptions made in the modelling of metal powder densification. It is expected that the rapid solidification typical in the atomisation of metals results in significant differences in behaviour when compared with material produced via casting and hot/cold working

Industry 1.61803: the transition to an industry with reduced material demand fit for a low carbon future

Arising from a discussion meeting in September 2016, this editorial introduces a special issue on the transition to a future industrial system with greatly reduced demand for material production and attempts to synthesize the main findings. The motivation for such a transition is to reduce industrial greenhouse gas emissions, but unlike previous industrial transformations, there are no major stakeholders who will pursue the change for their own immediate benefit. The special issue, therefore, explores the means by which such a transition could be brought about. The editorial presents an overview of the opportunities identified in the papers of the volume, presents examples of actions that can be taken today to begin the process of change and concludes with an agenda for research that might support a rapid acceleration in the rate of change.The work of J.M.A. and A.C.S. on this paper was funded by EPSRC grant reference EP/N02351X/1 and that of A.C.H.S. by EPSRC grant reference EP/K039326/1

The influence of UK emissions reduction targets on the emissions of the global steel industry

The steel industry is the world's largest industrial source of CO$_{2}$ emissions. Recent UK economic policies have led to reduced domestic steel production giving an apparent reduction in national emissions. However, demand for goods made from steel has not reduced. Emissions have thus been transferred not reduced and implementation of UK climate policies may in future expand this ‘carbon leakage.’ This paper explores how future UK demand for goods made from steel might be supplied while satisfying national climate policies, and how this will influence global CO$_{2}$ emissions. Current flows and stocks of steel are estimated from existing databases. Evidence from other developed economies suggests that per capita stocks are tending towards a saturation level so future demand is forecast from population growth and the expected rate of replacement of a stable stock. The carbon intensities of five different steel-making routes are used to predict the allowed scale of future domestic steel production within the industrial emissions allowances set in four energy pathways defined by the UK Government. The remaining requirement for steel must be sourced offshore and the associated emissions are predicted, to give an estimate of the global emissions arising from final demand in the UK. The results show that current UK climate strategy may have a limited effect in reducing the CO$_{2}$ emissions of the global steel industry, unless the UK shifts towards producing more of its own steel products with domestic secondary steel-making. This option would also increase the security of UK supply and support an expansion of UK manufacturing.This work was supported by EPSRC, grant references EP/K011774/1 and EP/K039326/1.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.resconrec.2016.01.00

The paleobiological record of photosynthesis

Fossil evidence of photosynthesis, documented in Precambrian sediments by microbially laminated stromatolites, cyanobacterial microscopic fossils, and carbon isotopic data consistent with the presence of Rubisco-mediated CO2-fixation, extends from the present to ~3,500 million years ago. Such data, however, do not resolve time of origin of O2-producing photoautotrophy from its anoxygenic, bacterial, evolutionary precursor. Though it is well established that Earth’s ecosystem has been based on autotrophy since its very early stages, the time of origin of oxygenic photosynthesis, more than 2,450 million years ago, has yet to be established

Continuous Interaction with a Virtual Human

Attentive Speaking and Active Listening require that a Virtual Human be capable of simultaneous perception/interpretation and production of communicative behavior. A Virtual Human should be able to signal its attitude and attention while it is listening to its interaction partner, and be able to attend to its interaction partner while it is speaking – and modify its communicative behavior on-the-fly based on what it perceives from its partner. This report presents the results of a four week summer project that was part of eNTERFACE’10. The project resulted in progress on several aspects of continuous interaction such as scheduling and interrupting multimodal behavior, automatic classification of listener responses, generation of response eliciting behavior, and models for appropriate reactions to listener responses. A pilot user study was conducted with ten participants. In addition, the project yielded a number of deliverables that are released for public access

A fresh look at the evolution and diversification of photochemical reaction centers

In this review, I reexamine the origin and diversification of photochemical reaction centers based on the known phylogenetic relations of the core subunits, and with the aid of sequence and structural alignments. I show, for example, that the protein folds at the C-terminus of the D1 and D2 subunits of Photosystem II, which are essential for the coordination of the water-oxidizing complex, were already in place in the most ancestral Type II reaction center subunit. I then evaluate the evolution of reaction centers in the context of the rise and expansion of the different groups of bacteria based on recent large-scale phylogenetic analyses. I find that the Heliobacteriaceae family of Firmicutes appears to be the earliest branching of the known groups of phototrophic bacteria; however, the origin of photochemical reaction centers and chlorophyll synthesis cannot be placed in this group. Moreover, it becomes evident that the Acidobacteria and the Proteobacteria shared a more recent common phototrophic ancestor, and this is also likely for the Chloroflexi and the Cyanobacteria. Finally, I argue that the discrepancies among the phylogenies of the reaction center proteins, chlorophyll synthesis enzymes, and the species tree of bacteria are best explained if both types of photochemical reaction centers evolved before the diversification of the known phyla of phototrophic bacteria. The primordial phototrophic ancestor must have had both Type I and Type II reaction centers

Measurement of the cross-section of high transverse momentum vector bosons reconstructed as single jets and studies of jet substructure in pp collisions at √s = 7 TeV with the ATLAS detector

This paper presents a measurement of the cross-section for high transverse momentum W and Z bosons produced in pp collisions and decaying to all-hadronic final states. The data used in the analysis were recorded by the ATLAS detector at the CERN Large Hadron Collider at a centre-of-mass energy of √s = 7 TeV;{\rm Te}{\rm V}$and correspond to an integrated luminosity of$4.6\;{\rm f}{{{\rm b}}^{-1}}$. The measurement is performed by reconstructing the boosted W or Z bosons in single jets. The reconstructed jet mass is used to identify the W and Z bosons, and a jet substructure method based on energy cluster information in the jet centre-of-mass frame is used to suppress the large multi-jet background. The cross-section for events with a hadronically decaying W or Z boson, with transverse momentum${{p}_{{\rm T}}}\gt 320\;{\rm Ge}{\rm V}$and pseudorapidity$|\eta |\lt 1.9$, is measured to be${{\sigma }_{W+Z}}=8.5\pm 1.7$ pb and is compared to next-to-leading-order calculations. The selected events are further used to study jet grooming techniques

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT