Yes / The slag pit furnace of the Trøndelag tradition for iron production is a very specific cultural-historical tradition in central Norway in the Early Iron Age, but few of these iron production sites have been excavated in their entirety and there is therefore a lack of information about their size, spatial layout and organisation in the landscape. The aim of this paper is therefore to investigate how magnetic geophysical methods can be used as a way of locating, delimiting and characterising activity zones and specific archaeological features associated with this tradition of iron production. The NTNU University Museum in Trondheim performed geophysical surveys of four different iron production sites, combining topsoil volume magnetic susceptibility measurements and detailed fluxgate gradiometer surveys. Analysing and comparing the survey results with sketches and topographic survey results, as well as comparable geophysical survey data from iron production sites elsewhere in Norway, made it possible to gain new and valuable cultural-historical and methodological knowledge. The topsoil volume susceptibility measurements revealed a strong contrast between the main production areas and the natural background measurement values, often in the range of 7–27 times the median background values. The absolute highest measured values were usually in the area closest to the furnaces, and within the slag mounds. Satellites of high readings could be interpreted as roasting sites for iron ore, and even areas with known building remains related to the iron production sites had readings stronger than the median. The fluxgate gradiometer data helped to characterise individual features further, with strong geophysical contrast between features within the iron production sites and the areas surrounding them. Also, by analysing their physical placement, geophysical characteristics such as contrast, magnetic remanence and size, it was possible to gain further insight into the spatial organisation by indicating the potential location of furnaces, the spread of slag and the handling of iron ore. The latter involved both where the roasted iron ore was stored and where it was roasted. The geophysical characteristics of the furnaces were less uniform than situations reported elsewhere in Norway, which can be explained by the reuse of furnaces and slag pits. The spread of highly remanent material in and around the furnaces and elsewhere within the limits of the iron production sites also created a disturbed magnetic picture rendering it difficult to provide an unambiguous archaeological interpretation of all the geophysical anomalies identified. In conclusion, these results showed that the geophysical methods applied made it possible to indicate the physical size, layout and internal spatial organisation of iron production sites of the Trøndelag slag pit furnace tradition.

The aim of this study was to work out whether bloomery activities might have left a geochemical imprint in two mires close to a known bloomery and identify differences between the geochemical signals in the mires. Therefore two peat profiles (140 cm deep) and a series of bulk samples (composite of 10-60 cm) were taken near the remains of a bloomery close to Ängersjö, Hälsingland, which has one documented radiocarbon date of AD 1300-1435. One profile was taken in the fen closest to the bloomery, the other profile was taken close to a nearby lake. Geochemical analysis of the peat samples was performed with X-ray fluorescence spectroscopy (XRF). The results were combined with previously taken data from a sediment profile from the lake ~120 m away and a pollen profile close to the bloomery. The results showed that the activities of the bloomery were visible in the geochemical signals of the peat core closest to the bloomery with two peaks in Pb and Zn, which coincide with the previous reported times of operation (1. AD 1030-1060; 2. AD 1300-1435), which also fits with the pollen record from the nearby peat record. The mire close to the lake, which is hydrologically not connected with the area where the bloomery was, did not show these increases in elements associated with iron processing and only a small peak of Pb was visible. Furthermore, the geochemistry of the bulk samples showed that a disturbance of the mire surrounding the lake was responsible for the geochemical changes observed in the lake,particularly as a source of increases in inferred biogenic Si observed in the sediment record (as increased Si/Al ratios) in association with human-related disturbance in the sediment record during AD 800-1200. Si concentrations in the bulk peat samples in the fen adjoining the lake range as high as 14% (≤23% as SiO2).

In 1886 Hans Hildebrand received a Bronze Age hoard found in a field that belonged to Eskelhem´s rectory. A record was made where Hildebrand presented and documented the artifacts. The following year Oscar Montelius reviewed the artifacts, which he described as horse gears. He compared the horse gears with similar artifacts found in Europe that roughly had the same dating in order to trace the origin of the hoard.  Montelius conclusion was that the hoard was created on Gotland around 500 BC. The entire hoard was made of bronze except for one of the bridles that was made of iron. According to Montelius this would mean that iron and the knowledge of iron making already had been adapted on Gotland in the late Bronze Age. Also the bridles were used so Montelius discussed the presence of horses on Gotland in the late Bronze Age, and if they had been of the race Gotland pony. Over100 years have passed since Montelius made his conclusion. The purpose of this paper is to see if Montelius conclusion on the Eskelhem hoard still holds, due to the progress of science, such as the discovery of new dating methods and all new artifacts that have been found. I will also review if the purpose of the deposition of the Eskelhem hoard was of sacral or profane purpose. In order to answer my questions I will use previous research in the areas of; the presence of horses in the Stone- and Bronze Age, iron making on Gotland during the time before the birth of Christ and hoards on Gotland dated to the late Bronze Age. Also I will use historical maps to create my own spatial analyze in order to see how the hoards were deposited.I have concluded that the Eskelhem hoard were deposited in peat soil, meaning that a connection to water and the Eskelhem hoard should be presumed and that the hoard were sacral. Montelius dating of the hoard to 500 BC are correct and also that the artifacts were used for horses on Gotland, which also means that horses existed on Gotland during the late Bronze Age. Most difficult to answer are the questionsconcerning the making of iron, whether or not the Eskelhem hoard was created on Gotland or not. Difficult due to the poor research made on iron making during the Bronze Age on Gotland. My conclusion is that parts of the hoard were made on Gotland, and parts were imported. The iron bridle was made on Gotland while the raw material used for iron production was imported.

This bachelor thesis examines changes in the spatial organization of iron production sites and charcoal pits, in the county of Dalarna during the period 1-1050AD. The purpose is to try to gain an understanding, about how the spatial changes reflect changes in the importance of the iron production in the iron age society, by discussing the iron production and its importance through a biographical perspective. 14C dates of 81 iron production sites and 32 charcoal pits have been analyzed in GIS. The analysis indicates that the early iron production sites, before 550AD, were in close connection with graves, while the later sites, mainly during the Viking age, had a close connection to waterways. This change could reflect a transition in the importance of the iron production, in the iron age society. During the early phase, the importance was mainly seen from the symbolical aspects of the iron production, while during the later phase, it was mainly seen from the economic aspects. The analysis also indicates a change in the spatial organization of the charcoal pits, during the later part of the iron age. During the period 790-1000AD they were positioned in close connection to the iron production sites, and after 1000AD, they were instead positioned in close connection to the water ways. This change could indicate a change in the functional organization of the iron productions process. The charcoal started to get shipped along the waterways to iron production sites, instead of positioning the charcoal pits close to the iron production sites. Not all the iron production sites were however located at rational economical positions in the landscape, during the later phase. At certain locations, iron was produced during a long period of the iron age, even though the locations had no connection to the waterways. This could indicate that some sites had special meanings, which stretched far back in time. In other words, their own biographies.

The most widely used process to reduce iron ore and to produce pig iron is the blast furnace. The blast furnace is a large source of CO2 emissions since it is a coal based process and due to that the main energy source and reducing agent is coke, it is difficult to reduce these further. IRONARC is a new method used to produce pig iron by reducing iron ore and all the energy used for heating comes from electricity, which gives the opportunity to use renewable resources. The process uses plasma generators that inject gas at high temperature and velocity into a slag that consists of iron oxides. The iron oxides are reduced in two steps that appear by using gas as reduction agent in the first step and carbon in the second step.   It exists in a smaller pilot plant scale and this project was the first step in the future upscaling of the IRONARC process. Computational Fluid Dynamics (CFD) modelling was used and the goal was to determine the penetration depth of the IRONARC pilot plant process by numerical simulation in the software ANSYS FLUENT. The penetration depth is of importance because to be able to scale up the process it is important to know the flow pattern and the structure of the flow in the process, which is dependent on how far into the slag the gas reaches. Two numerical models were made. First an air-water model that described the initial penetration of air injected into water. The air-water simulation was made with parameters and data from an experiment found in literature. This was done to build an accurate CFD model for the penetration depth in FLUENT and validate the model with the results of the penetration depth from the experiment. The air-water simulation gave good and promising results and yielded the same result regarding the penetration depth as the experiment.  The model for the penetration depth was then used with the IRONARC geometry and parameters. After simulation the penetration depth of the IRONARC process was determined. For the future, the penetration depth of the pilot plant needs to be measured and compared with the simulated result for the penetration depth.

Although concentrated solar power can be used to produce power using traditional electricity generation, energy storage has become a problem due to the intermittent supply of solar energy. By using solar energy in chemical production processes, the solar energy can be stored in a useful chemical product. The purpose of this thesis will be to examine the possibilities of a new solar chemical cycle the produces iron and ethylene from hematite (a form of iron oxide) and ethane using concentrated solar power. These two products are important stepping stones in the production of steel and polymers. This process could allow for the current process of steel production to move away from processes using coal and towards a more sustainable process using the hydrogen formed from the ethane cracking process and solar energy. The thesis will include: (1) the development of a new solar powered iron and ethylene combined cycle, (2) a feasibility study of a Concentrated Solar Heat Supply System (CSHSS) being developed at Georgia Tech, and (3) an assessment of the proposed cycle. The assessment will include an estimate of production including a thermodynamic ASPEN model, assessment of research to realize actualization of the theoretical cycle, an exergy analysis, and a heat exchanger analysis for the exchange of heat between the CSHSS and the chemical process.

<p>This is a story about Lao Pako. Lao Pako is located on a small hill on the southern bank of the river Nam Ngum in central Laos. Four seasons of archaeological fieldwork have yielded considerable amounts of pottery, metallurgical remains, glass beads, stone artefacts, spindle whorls as well as other material and structural information that have created a foundation for interpretation. The archaeological interpretation presents Lao Pako as a place where people came to perform rituals c. 1500 years ago. In these rituals, sophisticated combinations of pottery depositions, infant burials and iron production produced a narrative about what it means to be in the world. Things in and on the ground created, and continue to create, non-verbal sentences about life and death, fertility, decay and worldly reproduction. </p><p>The archaeological interpretation is, however, not the only valid story about Lao Pako. This is a place where spirits are; it is also a tourist resort and a national treasure. These other stories all work to create Lao Pako as a place of interest and are used in this thesis to define the archaeological story, and to visualize the aims and agendas inherent in the production of archaeological knowledge. </p><p>Using the conceptual apparatus of postcolonial and other critical theory, the thesis aims to critically deconstruct the archaeology performed by the author and others. It entails an explicit critique of the deterministic temporal unilinearity that is inherent in the archaeological narrative of the evolution of humankind, as well as against essentialist notions of culture and the dissociation of the past as exotic otherness. Thus, the stories about Lao Pako demonstrate the need to critically revise the role of archaeology in a postcolonial world, and create archaeological stories by which we are touched, moved and disturbed, without resorting to imperialist notions of time and progress.</p>

This is a story about Lao Pako. Lao Pako is located on a small hill on the southern bank of the river Nam Ngum in central Laos. Four seasons of archaeological fieldwork have yielded considerable amounts of pottery, metallurgical remains, glass beads, stone artefacts, spindle whorls as well as other material and structural information that have created a foundation for interpretation. The archaeological interpretation presents Lao Pako as a place where people came to perform rituals c. 1500 years ago. In these rituals, sophisticated combinations of pottery depositions, infant burials and iron production produced a narrative about what it means to be in the world. Things in and on the ground created, and continue to create, non-verbal sentences about life and death, fertility, decay and worldly reproduction. The archaeological interpretation is, however, not the only valid story about Lao Pako. This is a place where spirits are; it is also a tourist resort and a national treasure. These other stories all work to create Lao Pako as a place of interest and are used in this thesis to define the archaeological story, and to visualize the aims and agendas inherent in the production of archaeological knowledge. Using the conceptual apparatus of postcolonial and other critical theory, the thesis aims to critically deconstruct the archaeology performed by the author and others. It entails an explicit critique of the deterministic temporal unilinearity that is inherent in the archaeological narrative of the evolution of humankind, as well as against essentialist notions of culture and the dissociation of the past as exotic otherness. Thus, the stories about Lao Pako demonstrate the need to critically revise the role of archaeology in a postcolonial world, and create archaeological stories by which we are touched, moved and disturbed, without resorting to imperialist notions of time and progress.

Abstract This thesis explores early modern industrial dynamics and especially the long-term performance of iron production and its localisation in Central Sweden during the period 1368-1910. Iron production, iron export and localisation in a national perspective as well as the regional industrial development in Central Sweden during the period 1805-1910 are studied. The production and localisation changes of the industry in the early modern period were investigated by processing easily available but scattered data. The study of the iron industry in the period 1805-1910 was based census data on employment structure in the Central Swedish parishes in four benchmark years, 1805, 1855, 1890 and 1910 and was carried out with the help of statistical cluster analysis. The first important result is that the Swedish iron export increased rapidly in the 16th the 17th centuries. This had to do with the breakthrough of bar iron which soon replaced the old form of iron called osmund iron. The export continued to increase up to the 1740s. From the 1740s there was stagnation till the 1820s when an expansion commenced and in the rest of the period under study the export grew fourfold. The distribution of iron production showed variations as to geographical patterns over time and there were rather distinct chronological phases as well. An expansion of established ironworks and tilthammers commenced in the end of the 16th century and reached its highest annual average in the 1630s. The localisation of new establishments in the 16th and early 17th centuries was mainly concentrated to the interior of Central Sweden. The localisation became more and more scattered over the country in the early modern period. Thus, the tendency towards diffusion outside the administrative Bergslagen became more and more obvious in the 18th century with new ironworks and tilthammers in Northern and Southern Sweden. In the late 19th century the number of industrial parishes had increased and so had the share of employed in manufacturing industry. Furthermore, the industrial parishes were concentrated to a large cluster which covered the inner parts of Central Sweden. However, the analysis of industrial branches also showed a diversification where the wood, paper and pulp industries and above all the metal industries were fast growers. The metal industries also proved a geographical closeness to the traditional iron and steel industry The second main outcome of the investigation has to do with the continuity concerning the localisation of the iron industry. The historical continuity and the confinement to a certain area are evident from the analyses of various localisation factors in which a number of logit-models were employed. The status of a parish as industrial at one time point was to a great extent decisive for its status as industrial at a later date. The existence of iron ore mining in the parish and if the parish was situated inside the institutional region of Bergslagen also enhanced the probability for it to be defined as an industrial community also long after the institutional regulation had been abolished in the 1850s. In a long-term perspective, the analysis revealed that there was a marked continuity between the early modern patterns of localisation of the iron industry and the localisation of the engineering industrial firms in the 20th century. However, the early modern localisation did not show a significant connection with the industrial parishes’ localisation in 1855, 1890 and 1910, which means that the results are not unambiguous. The third main result of the study is that geographical vicinity of communities to others with industrial activities contributes to industrial growth. In this way industrial communities tend to concentrate geographically and thereby to form clusters. For 1855 this was not significant but for 1890 it was evident. For 1910 it was shown that if a parish had more than one neighbouring industrial community, the probability of its being industrial was great. In a long-term perspective it seems that agglomerations of industrial activities form an environment which can cope with episodes of increasing transformation pressure in a better way than isolated units. Geographical concentrations which, historically seen, are characterised by “industry in the air” have a high propensity to adapt to changes in the industrial environment.

In the iron production processes, sinters and pellets are mostly used as raw materials due to their consistency with respect to physical and chemical properties. However, natural iron ores, as mined, are rarely used directly as a feed material for iron processing. This is mainly due to the fact that they have small contents of iron and high concentration of impurities. Moreover, they swell and disintegrate during the descent in the furnace as well as due to low melting and softening temperatures. This work involves an investigation of the parameters that influence the use of natural iron ores as a direct feed material for iron production. Furthermore, it points out ways in which these can be mitigated so as to increase their direct use in iron production. Natural iron ore from Muko deposits in south-western Uganda was used in this study. Initially, characterisation of the physical and chemical properties was performed, to understand the natural composition of the ore. In addition, investigations were done to study the low temperature strength of the ore and its behaviour in the direct reduction zone. Also, simulations were performed with three models using the experimental data from the direct reduction experiments in order to determine the best model for predicting the direct reduction kinetics of natural iron ores. Chemical analyses showed that the Muko ore represents a high grade of hematite with an Fe content of 68% on average. The gangue content (SiO2+Al2O3) in 5 of the 6 investigated iron ore samples was &lt; 4%, which is within the tolerable limits for the dominant iron production processes. The S and P contents were 0001-0.006% and 0.02-0.05% respectively. These can be reduced in the furnace without presenting major processing difficulties. With respect to the mechanical properties, the Muko ore was found to have a Tumble Index value of 88-93 wt%, an Abrasion Index value of 0.5-3.8 wt% and a Shatter Index value of 0.6-2.0 wt%. Therefore, the ore holds its form during the handling and charging processes. Under low temperature investigations, new parameters were discovered that influence the low temperature strength of iron oxides. It was discovered that the positioning of the samples in the reduction furnace together with the original weight (W0) of the samples, have a big influence on the low temperature strength of iron oxide. Higher mechanical degradation (MD) values were obtained in the top furnace reaction zone samples (3-25% at 500oC and 10-21% at 600oC). These were the samples that had the first contact with the reducing gas, as it was flowing through the furnace from top to bottom. Then, the MD values decreased till 5-16% at a 500oC temperature and 6-20% at a 600oC temperature in the middle and bottom reaction zones samples. It was found that the obtained difference between the MD values in the top and other zones can be more than 2 times, particularly at 500oC temperature. Furthermore, the MD values for samples with W0 &lt; 5 g varied from 7-21% well as they decreased to 5-10% on average for samples with W0 ≥ 5 g. Moreover, the MD values for samples taken from the top reaction zone were larger than those from the middle and bottom zones. During direct reduction of the ores in a H2 and CO gas mixture with a ratio of 1.5 and a constant temperature, the reduction degree (RD) increased with a decreased flow rate until an optimum value was established. The RD also increased when the flow rate was kept constant and the temperature increased. An optimum range of 3-4g was found for natural iron ores, within which the highest RD values that are realised for all reduction conditions. In addition, the mechanical stability is greatly enhanced at RD values &gt; 0.7. In the case of microstructure, it was observed that the original microstructure of the samples had no significant impact on the final RD value (only 2-4%). However, it significantly influenced the reduction rate and time of the DR process. The thermo-gravimetric data obtained from the reduction experiments was used to calculate the solid conversion rate. Three models: the Grain Model (GM), the Volumetric Model (VM) and the Random Pore Model (RPM), were used to estimate the reduction kinetics of natural iron ores. The random pore model (RPM) provided the best agreement with the obtained experimental results (r2 = 0.993-0.998). Furthermore, it gave a better prediction of the natural iron oxide conversion and thereby the reduction kinetics. The RPM model was used for the estimation of the effect of original microstructure and porosity of iron ore lumps on the parameters of the reduction process. / <p>QC 20130531</p> / Sustainable Technology Development in the Lake Victoria Region