Of Hearths and Houses

During the 1993 East Texas Archeological Field School conducted at the Tyson site (41SY92) in western Shelby County, the junior author had an opportunity to participate in the excavation of a Caddoan hearth. The work was directed by Linda Lindsay, a graduate student in Anthropology at Southern Methodist University. This paper describes our findings and a few features of hearths and houses. One goal of the 1993 Field School was to explore the area around Feature 3 looking for evidence of a house. This was accomplished by opening a 6 meter by 6 meter unit referred to as Block 1. Feature 3 had been excavated in 1992 and found to be a 1.2 meter in diameter, round, basin shaped pit containing a large amount of daub, bone, and Caddoan pottery sherds. Near the bottom of the pit was a zone of ash. Charcoal and mussel shell from Feature 3 yielded three calibrated radiocarbon dates of about 1425 AD. When Block I was completely exposed, a number of other pits and postholes were seen in plan view. Our activity focused on Feature 9 on the western edge of Block 1. This 1.1 5 meter by O. 9 meter oval hearth was first revealed at 20 cm depth when ash was encountered. The feature contained large amounts of ash from in situ burning, nuggets of fired clay, a small amount of bone, and several burned sherds with ash adhering to their surfaces. The hearth was slightly basin-shaped and approximately 15 cm thick. A discontinuous thin layer of bright orange clay near its bottom was observed. The hearth had been prepared for use by digging a very shallow pit but no intentional clay lining was seen. Two large postholes were found in the area of Feature 9. Feature 17 was discovered beneath the eastern end of the hearth. It was 30 cm in diameter and had a smoothly rounded bottom at 75 cm below ground surface. Feature 12 was a very distinct posthole of similar proportions just west of the hearth. The diameter of F 12 was 27 cm and the depth was 65 cm below surface. How do we understand this feature? Specifically, does Feature 9 represent the central hearth of a Caddoan house? This question is currently difficult to answer because the outside wall of a putative house has not been identified. Possibly, Block l lies entirely inside a large house. The question may be easier to answer after reviewing accounts written by early Europeans visiting the area and reviewing the archeological findings at other East Texas Caddoan sites

Caddo Ceramic Sherd Assemblage from a Hearth Feature at the Cherokee Lake Site (41RK132) in Rusk County, Texas

There is a collection of plain and decorated ceramic sherds in the Gregg County Historical Museum from a feature, described as either a fire pit or a hearth, excavated by Buddy Calvin Jones in March 1956 at the Cherokee Lake site (41RK132) on Toawichi Creek in northern Rusk County, Texas. This assemblage is discussed in this article. The Cherokee Lake site is best known for its early 18th century Nadaco Caddo component, but it also has a Middle Caddo period (ca. A.D. 1200–1400) component. In Jones’ discussion of work he conducted at the Cherokee Lake site, he mentions the excavation of an Historic Caddo burial as well as a large “refuse pit” of prehistoric age, both in Area A of the site. The excavation of a fire pit or hearth in any area at the site is not mentioned by Jones, but it seems likely that the “fire pit/hearth” may be the same feature as the aforementioned refuse pit. In any case, this “fire pit/hearth” feature at the Cherokee Lake site contained a considerable number of plain and decorated ceramic sherds, as did the “refuse pit.” According to Jones, the refuse pit had “Hickory Engraved, Dunkin Incised, variant types, unidentified types of punctated and incised wares,” as well as a small Bullard Brushed jar, a fragment of a second Bullard Brushed jar, both from the upper part of the pit, and fragments of a plain bowl from the floor of the pit

Модернизация системы охлаждения пода руднотермической печи

В статье рассмотрена проблема износа футеровки пода в межэлектродном пространстве руднотермической печи. На основе анализа теплового баланса руднотермической плавки была поставлена задача по снижению износа футеровки пода в межэлектродном пространстве печи и увеличению кампании. Изложен вариант модернизации системы воздушного охлаждения пода. Была запроектирована система воздушного охлаждения пода и произведен расчет скорости воздушного потока, достаточной для снижения температуры наружной поверхности футеровки до 100 0С. Полученные решения послужили основой для моделирования системы воздушного охлаждения пода руднотермической печи.The article deals with the problem of lining wear hearth in the interelectrode space in ore-smelting furnace. Based on the analysis of the heat balance oresmelting furnace was tasked to reduce lining wear furnace hearth in the interelectrode space and increase campaign. Set out the option of upgrading air cooling hearth. Air cooling hearth was designed and calculated the velocity of the air is sufficient to reduce the temperature of the outer surface of the liner up to 100 0C. The resulting solutions were the basis for modeling air cooling ore-smelting furnace hearth

Optimization of multiple hearth furnace for biomass torrefaction

Gasification in entrained flow reactor and co-combustion of biomass in coal power plant are promising technologies of thermo-chemical conversion to produce electricity, heat, fuels and chemicals. Prior to injection in those reactors, biomass must be dried and ground to fine particles, until several hundreds of micrometers. These preliminary steps, especially grinding, consume large amounts of energy and represent obstacles that need to be overcome in order to expand the use of biomass in thermo-chemical processes. Torrefaction is a mild pyrolysis process carried out at 200 - 300 °C under inert atmosphere. It is a technology which allows moisture and low weight organic volatile components of biomass to be removed, producing a hydrophobic solid residue with an increased energy density (on a mass basis) and greatly reduced grinding energy consumption compared to fresh biomass. Electricity requirements for size reduction of torrefied wood are 50 to 85 % smaller in comparison with fresh wood. Therefore torrefaction leads to a more suitable product for transportation, storage and feeding. Currently, main applications for torrefied products are gasification and co-firing in coal power plant. Products can be used as a fuel either in pellet or powder after grinding. A state of the art of the existing torrefaction technologies has been performed. On the outcome of this study it appears that CMI's torrefaction process is one of the most promising technologies. It's a multiple hearth furnace whom main advantages are to allow the biomass torrefaction over a large range of residence time, temperature and biomass feedstocks. Within the framework of collaboration between French research centres CEA and CIRAD and the Belgium company CMI, the multiple hearth furnace developed by CMI has been adapted and optimized to torrefaction purpose. The main objectives were to reduce the production costs while improving significantly biomass properties. To achieve the objectives, an extensive experimental program was conducted in the torrefaction pilot plant of CMI which has a 40 kg/h capacity. Sampling methods and instrumentations were developed to analyse solids and gas products. The optimized process has proved experimentally its capacity to obtain well-torrefied product and its flexibility towards operating conditions and feedstock, which can be either wood or agricultural resources. Besides experimental work, a model of the torrefaction plant was built with Fluent®, CFD simulation software. This model has a supporting role in the extrapolation to industrial scale of the technology CMI. Thanks to furnace technical improvements, residence time has been reduced and reactor capacity has been increased. According to previous works, the torrefied products were characterized by a higher carbon content and energy density. Products had also more homogeneous properties and were much more friable than raw material. These results valid the adaptation choices, and allow to be confident for the upscaling to an industrial plant. (Texte intégral

CFD Modelling of Heat Transfer in Blast Furnace

Iron blast furnace is used in the metallurgical field to extract molten pig iron from its ore through a reduction mechanism. The furnace is a vertical shaft with circular cross section. It has five main parts: stack, belly, bosh, tuyeres and hearth. Amongst these regions, hearth is the most important one for the asset life of a furnace. Erosion of refractory lining of the hearth reduces the furnace’s campaign life. So it is necessary to understand the interactions occurring between the slag, molten metal and the refractories. But the severe operating conditions and very high temperature inside the hearth make it impossible to practically observe the processes taking place within it. In order to overcome this problem, the hearth is modelled by using various Computational Fluid Dynamics (CFD) soft-wares such as ANSYS Fluent, ANSYS-CFX, FLUENT for CATIA V5, ANSYS CFD-Flo etc. The numerical model is then supplied with data which are already known from practical situations as boundary conditions. Proper physical properties of the materials are also used as input. The software runs several simulations and provides us with the result that can validate the experimental observations up to the most accurate level. In this study, temperature distribution profile inside a blast furnace hearth has been shown by modelling a simple hearth with the help of ANSYS 15.0 Workbench. The model is simulated by changing some parameters and making several assumptions. The discrepancy in the calculated and the observed temperature opens up new scope for further improvement

The social origins of cooking and dining in early villages of western Asia

This paper explores social customs of cooking and dining as farming emerged in the earliest villages of Palestine and Jordan (12,650–6850 cal BC). The approach is a spatial analysis of in situ hearths, pits, bins, benches, platforms, activity areas, caches, and ground stone artefacts. Mortars, pestles, and bowls first appear in significant numbers in base camps of semi-sedentary Natufian hunter-gatherers. Elaborate and decorated, these artefacts imply a newly formal social etiquette of food-sharing. They were used within houses, near hearths, and in outdoor areas. The earliest farmers of the Khiamian and Pre-Pottery Neolithic A used simple, mostly undecorated, ground stone tools. One-room houses were often fitted with a hearth and a small mortar in the centre, features that also occur in outdoor areas. In the Early and Middle Pre-Pottery Neolithic B, firepits, milling stations, and storage features were placed on porches and outdoor areas near house doors. These areas formed a transition zone between house and community, where food preparation provided opportunities for social contacts. The most private rooms in houses were supplied with benches, platforms, and decorated hearths, and probably sheltered household meals. In the Late PPNB, when some villages grew to unprecedented sizes, storage, and cooking facilities were placed in constricted, private spaces comparatively hidden from community view. Numerous milling tools and multiple milling stations in individual houses suggest intensification of production of prepared foods. It is argued that adult women bore the brunt of the increased labour and that these activities placed them under new restrictions of daily activity and visibility in relation to village communities.</jats:p

Fire and memory: transforming place using fire at henge monuments

Henges — Late Neolithic to Early Bronze Age earthwork monuments — often have long life-histories of reuse and rebuilding over generations. At some sites, fire-lighting and the deposition of fire-altered materials played a significant role in certain phases of the use of the henge. This article reviews the evidence for fire in the life-histories of four henges in Scotland, and interprets the various ways in which fire was employed at different times and at different sites. It argues that fire had a transformational effect, not only upon monuments and materials, but it also characterized and transformed people’s experiences and memories of particular sites, thus creating links between monumental sites and quotidian experience during the Neolithic and Bronze Age in Scotland

Candles of Dickens in the Darkness of Victorian Era: Common Symbols in Christmas Books

The aim of this study is to stylistically analyze the common symbols in Charles Dickens’s Christmas Books, which revived the Christmas spirit in the dark Victorian era. Experiencing the vast impacts of Industrial Revolution, people in Dickens’s time were suffering from the consequences of industrialism, poverty, class distinctions and shifting values within a dark world. Upon combining sentimentality towards human nature, Dickens, in his Christmas stories, revived a festival which faded away from English life during the 19th c. Through this blending of a Christmas spirit in the dark Victorian era, Dickens drew the desired picture of a better future for his readers. His ‘Dickensian’ style enables questioning and judging the discrepancies in the society and the defects of humanity while entertaining the reader with the concerns of family harmony, forgiveness, charity, happiness, compassion and Christmas joy. Yet instead of presenting his messages explicitly, in the deeper structure, Charles Dickens directs his readers through the messages with the use of symbols in his five Christmas stories. To this end, this study aims at clarifying the common symbols in the stories of Christmas Books to suggest that Dickens lights a candle via his stories for his readers who were imprisoned in the dark Victorian age