Best Available Techniques (BAT) Reference Document:for:Iron and Steel Production:Industrial Emissions Directive 2010/75/EU:(Integrated Pollution Prevention and Control)

The BREF entitled ‘Iron and Steel Production’ forms part of a series presenting the results of an exchange of information between EU Member States, the industries concerned, non-governmental organisations promoting environmental protection and the Commission, to draw up, review, and where necessary, update BAT reference documents as required by Article 13(1) of the Directive. This document is published by the European Commission pursuant to Article 13(6) of the Directive. This BREF for the iron and steel production industry covers the following specified in Annex I to Directive 2010/75/EU, namely: • activity 1.3: coke production • activity 2.1: metal ore (including sulphide ore) roasting and sintering • activity 2.2: production of pig iron or steel (primary or secondary fusion) including continuous casting, with a capacity exceeding 2.5 tonnes per hour. The document also covers some activities that may be directly associated to these activities on the same site. Important issues for the implementation of Directive 2010/75/EU in the production of iron and steel are the reduction of emissions to air; efficient energy and raw material usage; minimisation, recovery and the recycling of process residues; as well as effective environmental and energy management systems. The BREF document contains 13 chapters. Chapter 1 provides general information on the iron and steel sector. Chapter 2 provides information and data on general industrial processes used within this sector. Chapters 3 to 8 provide information on particular iron and steel processes (sinter plants, pelletisation, coke ovens, blast furnaces, basic oxygen steelmaking and casting, electric arc steelmaking and casting). In Chapter 9 the BAT conclusions, as defined in Article 3(12) of the Directive, are presented for the sectors described in Chapters 2 to 8.JRC.J.5-Sustainable Production and Consumptio

Assembly of the 68- and 72-kD Proteins of Signal Recognition Particle with 7S RNA

Signal recognition particle (SRP), the cytoplasmic ribonucleoprotein particle that mediates the targeting of proteins to the ER, consists of a 7S RNA and six different proteins. The 68- (SRP68) and 72-(SRP72) kD proteins of SRP are bound to the 7S RNA of SRP as a heterodimeric complex (SRP68/72). Here we describe the primary structure of SRP72 and the assembly of SRP68, SRP72 and 7S RNA into a ribonucleoprotein particle. The amino acid sequence deduced from the cDNA of SRP72 reveals a basic protein of 671 amino acids which shares no sequence similarity with any protein in the sequence data libraries. Assembly of SRP72 into a ribonucleoprotein particle required the presence of 7S RNA and SRP68. In contrast, SRP68 alone specifically bound to 7S RNA. SRP68 contacts the 7S RNA via its NH2-terminal half while COOH-terminal portions of SRP68 and SRP72 are in contact with each other in SRP. SRP68 thus serves as a link between 7S RNA and SRP72. As a large NH2-terminal domain of SRP72 is exposed on SRP it may be a site of contact to other molecules involved in the SRP cycle between the ribosome and the ER membrane

Silicon uptake and isotope fractionation dynamics by crop species

That silicon is an important element in global bio-geochemical cycles is widely recognised. Recently, its relevance for global crop production has gained increasing attention in light of possible deficits in plant-available Si in soil. Silicon is beneficial for plant growth and is taken up in considerable amounts by crops like rice or wheat. However, plants differ in the way they take up silicic acid from soil solution, with some species rejecting silicic acid while others actively incorporate it. Yet because the processes governing Si uptake and regulation are not fully understood, these classifications are subject to intense debate. To gain a new perspective on the processes involved, we investigated the dependence of silicon stable isotope fractionation on silicon uptake strategy, transpiration, water use, and Si transfer efficiency. Crop plants with rejective (tomato, Solanum lycopersicum, and mustard, Sinapis alba) and active (spring wheat, Triticum aestivum) Si uptake were hydroponically grown for 6 weeks. Using inductively coupled plasma mass spectrometry, the silicon concentration and isotopic composition of the nutrient solution, the roots, and the shoots were determined We found that measured Si uptake does not correlate with the amount of transpired water and is thus distinct from Si incorporation expected for unspecific passive uptake. We interpret this lack of correlation to indicate a highly selective Si uptake mechanism. All three species preferentially incorporated light Si-28, with a fractionation factor 1000 x ln(alpha) of -0.33 parts per thousand (tomato), -0.55 parts per thousand (mustard), and -0.43 parts per thousand (wheat) between growth medium and bulk plant. Thus, even though the rates of active and passive Si root uptake differ, the physico-chemical processes governing Si uptake and stable isotope fractionation do not. We suggest that isotope fractionation during root uptake is governed by a diffusion process. In contrast, the transport of silicic acid from the roots to the shoots depends on the amount of silicon previously precipitated in the roots and the presence of active transporters in the root endodermis, facilitating Si transport into the shoots. Plants with significant biogenic silica precipitation in roots (mustard and wheat) preferentially transport silicon depleted in Si-28 into their shoots. If biogenic silica is not precipitated in the roots, Si transport is dominated by a diffusion process, and hence light silicon Si-28 is preferentially transported into the tomato shoots. This stable Si isotope fingerprinting of the processes that transfer biogenic silica between the roots and shoots has the potential to track Si availability and recycling in soils and to provide a monitor for efficient use of plant-available Si in agricultural production

Radial distribution of sap flux density in trunks of a mature beech stand

In a mature beech stand located in north-eastern Germany, xylem sap flux measurements were continuously performed during the 2002-2004 growing seasons. Ten representative trunks were studied using heated thermal dissipation probes. The measurements aimed at identifying principles governing radial profiles of xylem flux in beech trunks. The measurements were taken up to a trunk depth of 132 mm. The sap flow density in the pericambial xylem was found to vary among trees of different diameters, but was not considerably smaller in suppressed trees. A model for the radial distribution of sap flux density was formulated relating trunk radius and sap flow density. The model takes into account different trunk diameter. About 90% of the sap flux was found to occur in the outer two fifths of the trunk. Using this model, an adequate estimate of transpiration can be achieved at tree and stand level, even when the sap flux measurements are restricted to the outer trunk sectors.Distribution radiale du flux de sève dans les troncs d'un peuplement de hêtres. Nous avons mesuré les densités de flux de xylème dans le tronc de 10 individus représentatifs d'un peuplement de hêtres du nord-est de l'Allemagne. Ces mesures ont été conduites pendant les périodes de végétation de 2002 à 2004 en utilisant des sondes à dissipation de chaleur. Le but était de décrire les gradients radiaux de flux de sève dans le tronc des hêtres. Les mesures ont été réalisées jusqu'à une profondeur de 132 mm. La densité de flux de sève du xylème de la zone cambiale variait d'arbre en arbre en fonction du diamètre, mais cette densité ne diminuait pas sensiblement dans les arbres dominés. Un modèle de distribution radiale de la densité de flux de sève a été mis au point dans lequel le diamètre du tronc et la densité du flux de sève sont mis en relation. Le modèle prend en considération les arbres ayant des troncs de diamètres différents. Environ 90 % de l'eau circule dans les deux cinquièmes extérieurs du tronc. De cette façon, il est possible de calculer de manière suffisamment exacte la transpiration de l'arbre ou du peuplement tout entier, même si les mesures du flux de sève se limitent à la zone externe du tronc

What regulates the rhizodeposition of winter oilseed rape during growth?

PURPOSE: The goal of this work was to contribute to a better understanding of the process of rhizodeposition in crops and to find helpful approaches for creating a simple model of rhizodeposition. For this purpose, we tested three hypotheses about the relationships and changes in the relative C partitioning coefficients and their ratios. In particular, we analyzed the relationships between root growth, belowground respiration, rhizodeposition and other traits during plant growth. METHODS: The ranges of variation in 14 C partitioning coefficients and various plant traits were determined after 14 C labeling of four winter oilseed rape genotypes in three developmental stages. RESULTS: For all genotypes, we found very strong and significant correlations between the percentages of freshly assimilated C used for rhizodeposition and root growth. In addition, we showed that the ratios of the relative 14 C fluxes in the root-soil-soil gas system changed significantly during plant development and that the relative and absolute C fluxes of rhizodeposition followed different trends. The root growth rate and the change in the ratio of the percentages of 14 C in rhizodeposition and root tissue over time were the key factors that determined the absolute amount of rhizodeposited C. We also found that the C partitioning in a taproot system leading to root growth and rhizodeposition was similar to that of an adventitious root system. CONCLUSION: Based on our results, we conclude that using the identified key factors in combination with a root growth model, a simple model can be generated to describe rhizodeposition

Site-directed mutagenesis to deactivate two nitrogenase isozymes of Kosakonia radicincitans DSM16656T

Biological nitrogen fixation (BNF) is considered one of the key plant growth-promoting (PGP) factors for diazotrophic organisms. Whether the Fe and the FeMo nitrogenases of Kosakonia radicincitans contribute to its PGP effect is yet to be proven. Hence, for the first time we conducted site-directed mutagenesis in K. radicincitans to knock out anfH and/or nifH as means to deactivate BNF in this strain. We usedThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Methanol utilizers of the rhizosphere and phyllosphere of a common grass and forb host species

BACKGROUND: Managed grasslands are global sources of atmospheric methanol, which is one of the most abundant volatile organic compounds in the atmosphere and promotes oxidative capacity for tropospheric and stratospheric ozone depletion. The phyllosphere is a favoured habitat of plant-colonizing methanol-utilizing bacteria. These bacteria also occur in the rhizosphere, but their relevance for methanol consumption and ecosystem fluxes is unclear. Methanol utilizers of the plant-associated microbiota are key for the mitigation of methanol emission through consumption. However, information about grassland plant microbiota members, their biodiversity and metabolic traits, and thus key actors in the global methanol budget is largely lacking. RESULTS: We investigated the methanol utilization and consumption potentials of two common plant species (Festuca arundinacea and Taraxacum officinale) in a temperate grassland. The selected grassland exhibited methanol formation. The detection of 13C derived from 13C-methanol in 16S rRNA of the plant microbiota by stable isotope probing (SIP) revealed distinct methanol utilizer communities in the phyllosphere, roots and rhizosphere but not between plant host species. The phyllosphere was colonized by members of Gamma- and Betaproteobacteria. In the rhizosphere, 13C-labelled Bacteria were affiliated with Deltaproteobacteria, Gemmatimonadates, and Verrucomicrobiae. Less-abundant 13C-labelled Bacteria were affiliated with well-known methylotrophs of Alpha-, Gamma-, and Betaproteobacteria. Additional metagenome analyses of both plants were consistent with the SIP results and revealed Bacteria with methanol dehydrogenases (e.g., MxaF1 and XoxF1-5) of known but also unusual genera (i.e., Methylomirabilis, Methylooceanibacter, Gemmatimonas, Verminephrobacter). 14C-methanol tracing of alive plant material revealed divergent potential methanol consumption rates in both plant species but similarly high rates in the rhizosphere and phyllosphere. CONCLUSIONS: Our study revealed the rhizosphere as an overlooked hotspot for methanol consumption in temperate grasslands. We further identified unusual new but potentially relevant methanol utilizers besides well-known methylotrophs in the phyllosphere and rhizosphere. We did not observe a plant host-specific methanol utilizer community. Our results suggest that our approach using quantitative SIP and metagenomics may be useful in future field studies to link gross methanol consumption rates with the rhizosphere and phyllosphere microbiome