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Summary Many scholars of industrial ecology have focused on the institutional and organizational challenges of building and maintaining regional industrial symbiosis through the synergistic integration of material and energy flows. Despite the promise that these intellectual developments hold for the future dematerialization of industrial production, they rarely address the actual regulatory obstacles of turning wastes into raw materials. In this article we introduce a potential future industrial symbiosis around the Gulf of Bothnia between Finland and Sweden, and assess the regulatory bottlenecks related to waste by‐product consideration. We find that although the Gulf of Bothnia region has technological and economic potential for industrial symbiosis, the regulatory support for this is insufficient. We suggest a common pool resource‐based governance system that could utilize market and regulatory mechanisms in a regional‐level cross‐border system of governance. Importantly, the suggested governance system would protect the users of potential raw materials from unpredictable waste regulation, market risks related to large‐scale material flows, and societal risks of hazardous waste treatment.

The distribution, structural, and textural features, and behavior of alkali-bearing (K and Na) minerals are characterized from coking coals to feed coke and blast furnace (BF) coke. In coals, they are mostly represented by phyllosilicates (illite, montmorillonite, biotite, and muscovite) and feldspars. During the coking process, phyllosilicates retain a layered texture of their aggregates. Under coking conditions, feldspars keep the original outlines of mineral grains and bulk composition. There are no substantial changes in the volume of mineral grains and these alkali-bearing minerals have no physical effect on the coke matrix at coking temperatures. Thermodynamic calculations have shown that there are two major alkali-bearing mineral phases left in the system toward the end of the coking processalbite and leucite. Under BF conditions, Na is fully transferred to the molten phase above 1000 8C, while K partly occurs in leucite up to 1434 8C. The formation of intercalation compounds under BF conditions starts at 1127-1136 8C. Since K is referred to as a main intercalate phase in coke, then attention should primarily be focused on the presence of K-bearing minerals in coking coals. The quality of coals is assessed by the amount of K-bearing phyllosilicates and K-feldspars.[ Ã ] Dr.

The utilization of biomass fly ash and lime was investigated as cement replacements in blast furnace briquetting. Sample characterization included chemical (XRF) and mineralogical (XRD) analysis, particle size determination, and thermal behaviour (TGA/DSC-TGA). Additionally, the mechanical performance and fly ash, lime, and fly ash/lime mixtures as cement replacements were determined by incorporation in mortars tested by standardized methods (EN 196-1). Based on the results, detrimental alkali, sulphur, and chlorine contents of the biomass fly ashes do not seem to restrict use in briquetting. However, the utilization of fly ashes as cement replacements resulted in significant decline of 28 day compression strength values. The two different fly ash samples attested to 28 day compression strength of app. 72% and 55% of the respective control. Inferior mechanical performance was related to moisture absorption according to XRD and DSC-TGA and relatively larger particle size. Respectively, lime additions encouraged fly ash strength development only in the case of inferior fly ash performance related to the aforementioned effects. The results provide important information for the forthcoming manufacture of blast furnace test briquettes, which is to commence in the near future.

The behavior of sulfur-bearing minerals is characterized from coking coals to the feed coke and the blast furnace (BF) coke using field emission scanning electron microscope and thermodynamic calculations. In coals, they are represented by sulfides (pyrite, sphalerite, galena, chalcopyrite, and arsenopyrite) and sulfates (anhydrite and barite). During coking process, the minerals undergo phase transformations, but sulfur will be retained in the coke in mineral form for most of the minerals until the end of the coking process. Depending on the initial mineral in the coal, sulfur-bearing minerals will be transformed at the end of coking process into the following phases: pyrrhotite, wurtzite, Cu-Fe-S melt, CaS, and BaS. The amount of sulfur that will be kept in the coke in mineral form increases in the following order:gas flow under BF conditions facilitates liberation of sulfur from mineral phases in the Fe-S and Zn-S system. CaS and BaS are the most stable sulfur-bearing phases formed after sulfur-bearings minerals. The coals with elevated amounts of anhydrite and barite, or with high concentrations of Ca and Ba combined with S should be avoided for coking purposes. Complete elimination of mineral-related sulfur from coke under BF conditions occurs above 2000 C. Tools and MethodsThe samples of coals, feed coke, and BF coke we obtained from SSAB Europe Ltd., Raahe, Finland. The coals are represented by Jas Mos coal from Poland, Willow Creek coal from Canada, Riverside coal from Australia, and Severnaya-Vorkuta coal from Russia. The samples of BF coke were obtained by tuyere drilling. The length of the drill core (depth of drilling to the BF) was about 2 m. The supplied coals have, in general, relatively low content of sulfur, which usually do not exceed 0.5-0.6% (O. Kerkkonen, personal communication).Figure 4. Transformations of sulfur-bearing mineral phases (left column), and concentration of sulfur (right column) in mineral-carbon-gas (BF) system at 1000-2000 C. a) pyrhhotite, b) sphalerite-wurtzite, c) molten sulphide (Cu-Fe-S melt), d) CaS, e) BaS. www.advancedsciencenews.com www.steel-research.de steel research int. 2018, 89, 1700470

The effect of high-density polyethylene (HDPE) on the textural features of experimental coke was investigated using polarized-light optical microscopy and wavelet-based image analysis. Metallurgical coke samples were prepared in a laboratory-scale furnace with 2.5%, 5.0%, 7.5%, 10.0%, and 12.5% HDPE by mass, and one sample was prepared by 100% coal. The amounts and distribution of textures (isotropic, mosaic and banded) and pores were obtained. The calculations reveal that the addition of HDPE results in a decrease of mosaic texture and an increase of isotropic texture. Ethylene formed from the decomposition of HDPE is considered as a probable reason for the texture modifications. The approach used in this study can be applied to indirect evaluation for the reactivity and strength of coke.

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During coking processes, certain coal-associated minerals undergo various chemical changes, amongst which are dehydration, dehydroxylation, and decarbonation. In order to evaluate the character of CO 2 and H 2 O emission by a particular mineral, thermodynamic calculations for theoretical gas production were performed. Observations showed that the behavior of carbonates in respect of CO 2 emission vary substantially and, for that reason, their influence on the properties of coke differ. The amount of mineral-associated CO 2 released during the coking process is smaller than that which is produced by a carbonbased matrix. For each ton of coal, containing 1 wt% of carbonates, there will be c. 17.6-22.0 m 3 of CO 2 present at the stabilization stage of the coking process. However, the impact of a mineral-related gas phase should not be underestimated (in particular, for porosity development and cracks formation), mostly when the grain size of the minerals is quite large. The major CO 2 -related impact on coke properties can be referred to dolomite, magnesite, and calcite.