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The Roman provinces did not exist as entities but as a part of a complex system involving their urban and rural landscape, communications and networks. This paper explores evidence for ceramic production within the territory of the Augustan colony of Patras, highlighting the city’s significance as a major production center due to its strategic position in regional and long-distance trading networks. Regarding the archaeological evidence, 60 sites with evidence for ceramic production were studied, providing new data on their architectural structures, workshops and kilns as well as spatial organization within Patras and its territory. The prime focus of the work, focused on the definition of local Roman wares. Hence, 150 samples were selected from the kilns and their surrounding area for typological and fabric analysis. This paper offers the first systematic archaeometric analysis of Roman ceramics from the city of Patras and serves as a major guide-line for defining what was actually produced locally (e.g. grey and red sigillatas, plain ware vessels, ceramic building materials and amphorae). Petrographic analysis enabled us to determine the local compositional patterns establishing that there are five fabrics encountered among the various workshops with few compositional differences, indicating that they derive possibly from the same locally available clay deposits. Imported (Italian) terra sigillatas could also be successfully distinguished. Mineralogical analysis through X-Ray Powder Diffraction (XRPD) allowed the study of the nature of the raw materials used and enabled the estimation of kiln firing temperatures, which ranged from 700 to 1100 °C, thereby offering vital insights into ceramic technology. [ABSTRACT FROM AUTHOR]

Fused magnesia is a main irreplaceable raw material of magnesia-carbon bricks for the linings of steelmaking converters, steelmaking electric furnaces and refining ladle slag lines,which has a production capacity of 4 miilion tons in southern Liaoning. However, due to its downstream market, production raw materials, as well as production technology and equipment,problems for the fused magnesia production exist such as the imbalance of supply and demand,high energy consumption and large fluctuation of product quality. Therefore, the status and changes of fused magnesia in southern Liaoning in recent years were expounded. The future development trend of fused magnesia was pointed out. [ABSTRACT FROM AUTHOR]

The medieval monument of Kerpijlitepe is located at an altitude of 208–210m sea level, in the west of the Republic of Azerbaijan, near the village of Borsunlu of the Goranboy district, on the bank of the Gazanbulag River. The name of the site is associated with the presence of numerous shards of burnt bricks on its territory. In 2016-2018, archaeological excavations were conducted in 3 phases with short breaks in Kerpijlitepe. Archaeological studies demonstrate that in the XIII centuries there was a medieval castle on this territory. Some specialists believe that there is a “caravanserai” on this territory, a typical structure for the medieval East. During excavations, a large part of the medieval castle was uncovered. Of the four semicircular outposts, only the front two are well preserved. During the excavations, remains of dwellings, brick kilns, rich fi nds of ceramics, metal, bone, glass and stone, copper coins, etc. were also found. In the X–XIII centuries Kerpijlitepe turned into a densely populated urban settlement and maintained ties with many craft, trade and cultural centers of Azerbaijan, and especially with cities such as Shamkir and Ganja.

Biochar boosts soil fertility and helps plants to withstand drought. Its production locally has been a challenge and that is why an Indigenous Biochar Production Kiln (IBPK) was conceived, designed and fabricated at the Workshop of the Agricultural Technology Department, Federal Polytechnic, Ile-Oluji, Ondo State, Nigeria. IBK convert biomass to carbon-rich organic material through thermal energy. The IBPK has two drums, the Internal Retort Drum (IRD) and External drum of diameters and heights of 350 mm x 600 mm and 500 mm x 800 mm respectively. The total weight of the IBPK was 82.50 kg. The IRD of 116 kg/m3 volume was loaded with 55 kg biomass from wood waste, covered, and placed inside the external drum. The space between the outer wall of the IRD and the inner wall of the outer drum was 75 mm enough to contain firewood lighted and covered to produce the heat needed for the wood waste inside the IRD to convert it to Biochar. Smoke from the IBK escaped through the chimney attached to the external drum’s lid. The operating time for the carbonization was 182 minutes and the conversion efficiency of the IBPK was 71 %. The average temperature of the IBPK during the conversion was 269 °C. The test carried out on the produced Biochar showed the presence of macro elements that included Nitrogen (2.95%), Phosphorus (21.79%), Potassium (4.95%) and Carbon (70.31%). The fabrication cost was Fifty-Two Thousand, Two Hundred Naira only (₦52,200:00). The IBPK is recommended for farmers to produce Biochar as needed for improved farm yield, and young graduates who want to go into Biochar production as a way out of unemployment.

In masonry construction, the most commonly used building unit all over the world is the burnt clay brick. Adding waste materials in certain percentages to these bricks helps in eliminating the environmental burden occurring in the form of excessive waste accumulation on open land sites, leading to sustainable and economical construction. This research program aimed to examine the feasibility of using waste marble powder (WMP) and sugarcane bagasse ash (SBA) in the manufacturing of clay bricks. WMP was collected from local marble cutting workshops, whereas SBA was prepared by burning the waste sugarcane obtained from various sugar mills in the local area. Brick specimens incorporating 5%, 10%, 15%, and 20% of hybrid WMP and SBA were prepared at a local brick kiln. Burnt clay bricks were transported to the laboratory, and their mechanical and durability properties were evaluated. A reduction in weight per unit area of brick specimens incorporating waste materials was observed, allowing them to be easily handled and transported. Decreased compressive strength was due to the addition of waste materials in comparison with conventional clay bricks. However, waste percentages up to 15% satisfied the criteria for the minimum compressive strength as per the Building Code of Pakistan (BCP). All tested samples showed flexural strength greater than 0.65 MPa. Tested bricks incorporating 10% and 20% of waste materials had water absorption values of 18% and 21%, respectively, which are higher than that of conventional clay bricks. Moreover, bricks incorporating waste materials exhibited a higher initial rate of absorption than conventional clay brick; therefore, such bricks need to be wet well before use in masonry construction. Brick specimens showed less than 1% weight loss, and bricks exhibited no signs of distress and cracking after 50 freeze-thaw cycles. A decrease in compressive strength was observed due to sulphate exposure. However, specimens with 10% waste materials still satisfied the minimum compressive strength requirement of BCP. Based on this study, it can be concluded that bricks with up to 10% hybrid waste materials (WMP and SBA) will assist in the environmental issues of these wastes, leading to more sustainable and economical masonry construction. [ABSTRACT FROM AUTHOR]

The disposal of crop residues from agricultural fields is often seen as a burden due to the difficulties involved. However, this study aims to turn pigeonpea stalks into biochar, which can serve as a fuel substitute and soil amendment to sequester carbon. Different pyrolysis methods were employed to investigate the variations in yield, physicochemical characteristics, and higher heating value (HHV) of biochar produced from pigeonpea stalks. The biochar produced using a muffle furnace exhibited higher fixed carbon and ash content. These characteristics make it beneficial for restoring degraded agricultural soils by enhancing carbon sequestration. In addition, the muffle furnace biochar demonstrated a total potential carbon ranging from 262.8 to 264.3 g of carbon per kilogram of biochar, along with a CO2 reduction potential ranging from 77.17 to 79.68 CO2 eq per kg. Both the European Biochar Certificate and the International Biochar Initiative confirmed the agronomic abilities of the biochar and its compliance with the highest quality standards for soil carbon sequestration, with 0.11 H/C and 0.7 O/C ratios. Furthermore, biochar produced by muffle furnace from pigeonpea stalks exhibited superior fixed carbon recovery efficiency (181.66 to 184.62%), densification (5.86 to 6.83%), energy density (1.77 to 2.06%), energy retention efficiency (54.80 to 56.64%), fuel ratio (18.95 to 22.38%), and HHV (30.66 to 32.56 MJ kg−1). Additionally, it had lower H/C and O/C ratios, suggesting its potential as an alternative solid fuel. The results of the characterization of biochar with scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) revealed that the biochar samples prepared with both the methods had carbonyl (C=O), C=C, and aromatic C-H functional groups; however, the biochar prepared in the muffle furnace had more porosity. In summary, this study highlights the potential of using pigeonpea stalks to produce biochar, which can be utilized as a renewable fuel substitute and soil amendment to sequester carbon. The biochar derived from the muffle furnace exhibited desirable physicochemical characteristics, high carbon content, and excellent energy properties, making it a promising option for various applications. [ABSTRACT FROM AUTHOR]

Since ages ago until today, traditional ceramic kilns in Iran were the company of every potter; each of which had different heating methods in each region of the country and period of construction which was formed according to the region. Iranian potters of different ages, along with the progress in the industry, changed their ceramic kilns in order to improve the quality of wares. depending on the local conditions, these changes are dissimilar in each place. The purpose of this research is to identify and investigate traditional Iranian ceramic kilns Therefore, it only seems necessary to classify these kilns. This research used a descriptive-analytical method, in which research information sources are based on the data from archaeological excavations and field visits. These kilns can be classified in terms of placement in the ground, draft, heating methods, and atmospheric conditions inside the kilns. In terms of the location of the kilns in the ground, it has been classified into three categories: kiln on the ground, half buried, and underground which is the primary element of classification in this research. so, the article seeks to answer this question: How can ceramic kilns in Iran be classified according to their technical structure?

The origin of fish smoking dates back to antiquity. In ancient times, fish was hung over a fire which helped to reduce its moisture content. Further advancement was made traditionally by the erection of mud, bricks or corrugated iron angle bar. The gas smoking kiln has been developed using locally available materials in the study area towards improving the existing fish smoking kiln techniques. The objective of this work is to improve the quality of smoked fish in Kainji Lake Basin Area in Nigeria at minimum production cost. The preliminary test performance of the kiln has been conducted using Clarias gariepinus, known generally as catfish. The result obtained shows that the kiln is less labour intensive and can handle different sizes of fish faster with better appearance of the end product than the conventional smoking methods.

Lime is an important industrial raw material widely used in iron- and steel-making, flue gas desulfurization, construction, and papermaking industries. Lime is generally obtained via calcining limestone in a kiln, i.e., limestone is heated and decomposed to generate lime and carbon dioxide (CO2). In the conventional lime calcination, the CO2 released by the limestone decomposition is mixed with the flue gas because the fuel is burned in the shaft kiln, requiring gas separation for CO2 capture. The new lime calcination process using CO2 as a circulating carrier gas to heat limestone particles can avoid the above mixing problem, thereby directly capturing the CO2 generated by limestone decomposition, which is expected to reduce carbon emissions from lime production by approximately 70%. However, the new calcination process based on CO2 heating is quite different from the conventional calcination process. To understand the new calcination process and accurately design and optimize it, a mathematical model of the lime calcination process based on CO2 heating was established. Based on the model, a shaft kiln with a capacity of 200 t·d−1 was simulated and calculated. In addition, profiles of key parameters such as the gas-solid temperature difference, gas flow rate, gas temperature, particle surface temperature, reacting interface temperature, and conversion ratio in the shaft kiln were obtained. Besides, the three operating parameters (feed gas temperature, feed gas flow rate, and radius of the feeding limestone particle) on the calcination were analyzed. The following observations were made: (1) the lower the feed gas temperature, the lower are the final conversion ratio, pinch temperature difference, and tail gas temperature of the kiln. In addition, the changing trend of the final conversion ratio and pinch temperature difference conforms to a quadratic polynomial law, and the changing trend of the tail gas temperature conforms to a linear law. (2) The lower the feed gas flow rate, the lower are the final conversion ratio, pinch temperature difference, and tail gas temperature of the kiln. Moreover, the changing trend of each parameter conforms to a quadratic polynomial law. (3) Finally, the larger the radius of the feeding limestone particle, the lower is the final conversion ratio of the kiln, the higher is the tail gas temperature, and the greater is the pinch temperature difference. The changing trends of various parameters conform to cubic polynomial laws. Compared with the feed gas temperature and the feed gas flow rate, the radius of the feeding limestone particle has a greater impact on the pinch temperature difference and the tail gas temperature when the final conversion ratio changes in the same range.

The paper presents the results of a pottery workshop studies. The workshop was discovered during excavations in the city of Azov on Sotsialistichesky lane, 53 in 2015. It was located in the central area of medieval Azak and was a pottery production complex, consisting of a two-tier kiln and a kiln pit interconnected with a furnace channel. Almost all ceramic material from the filling of the firing chamber were locally produced vessels - products of this workshop. It is represented by one-handle glazed jugs of small and medium size with typical traces of defects (overfiring, cracks, deformations). This workshop had a narrow specialization and small production volume. Judging by stratigraphy and numismatic data, it ceased to function in the beginning of the first decade of the 14th century.

The results from archaeological fieldwork between 2014 and 2016 at Burdiehouse, Edinburgh, have revealed evidence of structures, pits and enclosures related to rural settlement and activity ranging across the Early Medieval period from the 7th century AD up to the 12th century AD. A suite of features included a truncated stone platform, remains of a small post-built building with a hearth and numerous pits, postholes and curvilinear ditches. In addition, a circular clay-lined kiln was recorded. Radiocarbon dating indicates that while the building and hearth, the stone platform and numerous of the pits, postholes and linear features related to activity between the 7th and 10th centuries AD, the kiln was a later feature, dated to the 12th century AD. The evidence for rural Early Medieval settlement sites as identified at Burdiehouse is limited but recent work has emphasised how important they are for understanding everyday activity in this period. [ABSTRACT FROM AUTHOR]

The article highlights the development of cheap affordable highly efficient catalytic oxidation system of harmful components of industrial flue gases of carbon graphite enterprises, its design features according to the parameters of furnace equipment, which will significantly improve the environmental safety of metallurgical and machine-building enterprises. The presented calculation and design solutions, in addition to carbon production, can be used in environmental protection technologies at other environmentally hazardous facilities to neutralize toxic emissions. The paper presents the calculation of the catalytic CO oxidation reactor made for the real flow rate of flue gases with temperature range 270-390 °C, which come out of the combustion chamber of the Riedhammer «first fire» kiln, heated by the flue gases. For such medium exothermic processes, mass and heat transfer between gas flow and the outer surface of the catalyst grains is sufficient intense. In this case for description of the catalytic process in the reactor is sufficient to use quasi-homogeneous single-phase model. The model of plug-flow reactor with a fixed bed of catalyst was used to calculate the flow parameters of the gas mixture through a reactor loaded with a composite zeolite-based manganese-oxide catalyst in the process of catalytic CO oxidation. The calculation results obtained using the software CHEMCAD 7.1.5 were almost identical to the previously made calculation. The peculiarity of the suggested solution was the use of the designed catalytic reactor for treatment of large volume of flue gases with low concentrations of CO at the companies of electrode carbon graphite production. [ABSTRACT FROM AUTHOR]

In 1959, Victor Teodorescu investigated a pottery kiln discovered in the territory of the village of Țintești, near the city of Buzău. The kiln, partially destroyed during the construction of a road, was composed of the stoker's pit, the kiln chamber with a central pillar, the grate, and the combustion chamber. Two intact vessels and several potsherds were found in the kiln. The research result remained unpublished. This note presents the report compiled at the completion of the investigations and the graphic part created by the author of the excavation, found in the archive of the County Museum of History and Archaeology Prahova. The illustration has been complemented with maps that include the area and photographs and archaeological materials recently discovered. [ABSTRACT FROM AUTHOR]

Brick kiln workers were evaluated in the field using otorhinolaryngologic and head and neck surgery (ENT) assessments. One-hundred and twenty laborers were assessed. The subjects were divided into three categories according to the work area: before the brick kiln, in the brick kiln, and after the brick kiln. Two evaluations were made, a questionnaire and an ENT examination. If structural changes were observed during the examination, the complication was deemed structural. Seventeen laborers who completed the questionnaire did not participate in the examination. A total of 103 laborers participated in the study: 29 before the brick kiln, 63 in the brick kiln, and 11 after the brick kiln. While general otologic complications were observed in 26 (25.2%) laborers, structural otologic complications were observed in 2 (1.9%). While general nasal complications were observed in 70 (68.0%) laborers, structural nasal complications were observed in 27 (26.2%). Although the general otologic and structural nasal complication rates were higher in the brick kiln group, the general, structural otologic, and nasal complication rates did not reach statistical significance among groups (p > 0.05). Both the general and structural nasal complication rates were significantly higher in laborers who had worked for more than 10 years and did not wear a mask (p < 0.01). We detected prominent nasal pathologies in brick kiln workers in our ENT-based study. These pathologies were much more common in laborers who had worked for over 10 years and did not wear a mask. [ABSTRACT FROM AUTHOR]

Refuse-derived fuel (RDF) from municipal solid waste (MSW) is an alternative fuel (AF) partially replacing coal/petcoke in a calciner/kiln of cement plant. The maximum thermal substitution rate (TSR) achieved through RDF is 80–100% in the calciner, while it is limited to 50–60% in the kiln burner. Different AF pre-combustion technologies, advancements in multi-channel burners, and new satellite burners have supported high TSR. Extensive efforts in modelling kiln burner and calciner lead to enhance TSR. However, the cement industry faces operational issues such as incomplete combustion, increased specific heat consumption, reduced flame temperature, and kiln coating buildup. There is an interest in RDF gasification, a promising alternative to eliminate the operational issues of the cement industry, which needs to be integrated with the existing cement plant. The article reviews the integration of gasification in cement production and various experimental and modelling studies of the direct firing of AF/RDF in the kiln/calciner. The features and technology status of both approaches are compared. The different gasification integration technologies with varied configurations for cement plant calciner are highlighted. The article emphasizes the need to develop suitable calciner/kiln-gasifier models for predicting calciner output based on different RDFs. [ABSTRACT FROM AUTHOR]

The production of catalysts such as zeolites is a complex multiscale and multi-step process. Various material properties, such as particle size or moisture content, as well as operating parameters—e.g., temperature or amount and composition of input material flows—significantly affect the outcome of each process step, and hence determine the properties of the final product. Therefore, the design and optimization of such processes is a complex task, which can be greatly facilitated with the help of numerical simulations. This contribution presents a modeling framework for the dynamic flowsheet simulation of a zeolite production sequence consisting of four stages: precipitation in a batch reactor; concentration and washing in a block of centrifuges; formation of droplets and drying in a spray dryer; and burning organic residues in a chain of rotary kilns. Various techniques and methods were used to develop the applied models. For the synthesis in the reactor, a multistage strategy was used, comprising discrete element method simulations, data-driven surrogate modeling, and population balance modeling. The concentration and washing stage consisted of several multicompartment decanter centrifuges alternating with water mixers. The drying is described by a co–current spray dryer model developed by applying a two-dimensional population balance approach. For the rotary kilns, a multi-compartment model was used, which describes the gas–solid reaction in the counter–current solids and gas flows. [ABSTRACT FROM AUTHOR]

The wealth and diversity of decoration on Greek pottery continues to attract science-based attention. The availability of increasingly powerful analytical techniques has allowed the nature of the decoration to be investigated in ever-finer detail, down to the nano-particle level. Such work has gone hand in hand with replication experiments ranging from sourcing raw materials to experimental firing. As a result, there is a fuller understanding of the many material and other factors controlling the quality of a range of painted or coloured decorations, most notably black gloss, seen to best effect in the Black and Red Figure–style vases of Attic potters-painters in the sixth to fourth centuries BC. Light has also been shed on the manner in which a few of these craftspeople adapted established techniques to give special effects.Reviewing the progress made on the decoration and firing of several pottery classes as well as other ceramics, such as terracotta figurines, this paper places this information into context in two ways. On the one hand, it covers the corresponding evidence for the decoration and firing of pottery of the Greek Neolithic and Bronze Age to chart diachronically the craft's technological development. On the other hand, it considers recent archaeological evidence for ceramic production.

A large collection of goose bones was recovered from excavations at Wheatcroft Farm, Bradwell, Norfolk. The goose bones were of particular interest due to the large quantity present and the presence of medullary bone in some of the specimens. All of the goose bones derived from two 11th-12th century contexts found in close association with a grain drying kiln and related sunken structure. The majority of the bones came from a single posthole. Evidence from body part representation, butchery marks and the occurrence of medullary bone is examined. Domestic geese are common on medieval sites in England and the element distribution and butchery marks are suggestive of waste from carcass preparation for cooking, with the meatiest elements largely having been removed. It seems possible that goose 'crowns' were being prepared and then cooked in or close to the kiln. The presence of medullary bone is unusual due to the more seasonal laying behaviour of geese compared to chickens and is examined in detail. [ABSTRACT FROM AUTHOR]

Charcoal is produced in large quantities in the Portuguese region of Alentejo mainly using traditional brick kilns. Information about this type of carbonization technology is scarce, which makes it urgent to characterize the process as a starting point for performance improvements. In this context, this study aims to characterize the operation of a cylindrical brick kiln (≈80 m3) during regular wood carbonization cycles. Relevant process parameters were monitored along with the yields and/or composition of the main products (carbonization gas, charcoal, and charcoal fines) to evaluate the mass balance of the process. The results show that the bulk of the kiln operates at temperatures below 300 °C, which greatly limits the quality of the charcoal. For instance, the fixed carbon content of charcoal can easily be as low as 60 wt.%. The yield of charcoal is also low, with values below 25 wt.% of dry wood feed. This means that significant quantities of by-products are generated in the process with little or no commercial value. Modifications in the carbonization process are needed to improve efficiency, charcoal quality, and environmental acceptance to sustain this activity in regions where it still represents vital income related to wood-waste management. [ABSTRACT FROM AUTHOR]

Copyright of Archaeologia Historica is the property of Masaryk University, Faculty of Arts and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper explores the formation of networked ceramic factories before the mid-eighteenth century in early modern China. Enquiring into the role of the state and private entrepreneurs in production innovation and design, it explores the notion of a 'factory'. In the context of large scale traditional production in East Asia, I periodize the evolving organizational structure of China's model of ceramic production and discuss two aspects of the state's negotiation with regional commercial kilns: 1) the impact on kiln structures and the exploitation of raw materials such as porcelain stones and colour pigment, and 2) an early modern design system which simultaneously regulated aesthetic forms, technological experiments, and fiscal planning. [ABSTRACT FROM AUTHOR]

The performance evaluation of refractory brick produced using Isan Ekiti clay (Ball clay and Kaolin) with saw dust as the combustible materials was investigated with a view of determining the most suitable percentage compositions. The clay samples were sourced from Isan Ekiti was crushed, pulverized, and sieved to produce very fine grains of less than 120 μm particle size distribution for all samples. Four compositions were developed from admixture of the clay and combustible materials. Samples produced from the compositions were then tested for shrinkage, porosity, bulk density, average crushing strength, and water absorption after firing to 1000 oc. Samples A-D had percentage total shrinkage ranging from 8% - 20% with corresponding bulk density ranging from 0.66g/cm3 – 1.07g/cm3. All the samples had crushing strength ranging from 1.1- 4.2 N/mm2 with corresponding percentage porosity ranging from 47.7% - 65.2%, while the percentage water absorption range from 41.3% - 98.4%. It was discovered that the higher the combustible materials the higher the shrinkage, porosity and water absorption, while the lower the bulk density and crushing strength of the bricks. However, sample D of the bricks produced with the lowest percentage combustible gave the average result when considering the percentage shrinkage, porosity, bulk density, crushing strength, and water absorption. Therefore, sample D with (70% of kaolin, 15% of ball clay, and 15% of saw dust) was used in the production of refractory bricks, and thereafter used to build a testing kiln.

The performance evaluation of refractory brick produced using Isan Ekiti clay (Ball clay and Kaolin) with saw dust as the combustible materials was investigated with a view of determining the most suitable percentage compositions. The clay samples were sourced from Isan Ekiti was crushed, pulverized, and sieved to produce very fine grains of less than 120 μm particle size distribution for all samples. Four compositions were developed from admixture of the clay and combustible materials. Samples produced from the compositions were then tested for shrinkage, porosity, bulk density, average crushing strength, and water absorption after firing to 1000 oc. Samples A-D had percentage total shrinkage ranging from 8% - 20% with corresponding bulk density ranging from 0.66g/cm³ - 1.07g/cm³. All the samples had crushing strength ranging from 1.1-4.2 N/mm² with corresponding percentage porosity ranging from 47.7% - 65.2%, while the percentage water absorption range from 41.3% - 98.4%. It was discovered that the higher the combustible materials the higher the shrinkage, porosity and water absorption, while the lower the bulk density and crushing strength of the bricks. However, sample D of the bricks produced with the lowest percentage combustible gave the average result when considering the percentage shrinkage, porosity, bulk density, crushing strength, and water absorption. Therefore, sample D with (70% of kaolin, 15% of ball clay, and 15% of saw dust) was used in the production of refractory bricks, and thereafter used to build a testing kiln. [ABSTRACT FROM AUTHOR]

The use of calcined clays as supplementary cementitious materials provides the opportunity to significantly reduce the cement industry's carbon burden; however, use at a global scale requires a deep understanding of the extraction and processing of the clays to be used, which will uncover routes to optimise their reactivity. This will enable increased usage of calcined clays as cement replacements, further improving the sustainability of concretes produced with them. Existing technologies can be adopted to produce calcined clays at an industrial scale in many regions around the world. This paper, produced by RILEM TC 282-CCL on calcined clays as supplementary cementitious materials (working group 2), focuses on the production of calcined clays, presents an overview of clay mining, and assesses the current state of the art in clay calcination technology, covering the most relevant aspects from the clay deposit to the factory gate. The energetics and associated carbon footprint of the calcination process are also discussed, and an outlook on clay calcination is presented, discussing the technological advancements required to fulfil future global demand for this material in sustainable infrastructure development. [ABSTRACT FROM AUTHOR]

Copyright of Art-Sanat Journal / Art-Sanat is the property of Art-Sanat and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Maize straw- and rice husk-derived biochars were produced in a simple metal kiln without automated control. Their characteristics and effects on crop productivity were investigated in three fields in Nepal. The maximum temperature inside the kiln reached ~ 450 °C; the charring reaction was maintained for 90 min and 10 h for maize straw- and rice husk-derived biochars, respectively, until 30 °C was reached. The physicochemical properties of the biochars were similar to those of biochars manufactured previously in electric furnaces with automated control. Compared with control soil, incorporation of maize straw- and/or rice husk-derived biochars into soil significantly (p < 0.05) increased spinach biomass, onion bulb, millet and maize yields. The increase in crop productivity varied from 12.8% (millet yield at 10 t ha−1 maize straw-derived biochar addition) to 220% (spinach biomass production at 10 t ha−1 rice husk-derived biochar addition). Further research is needed to standardize the operating conditions of biochar manufacturing in a kiln to optimize crop productivity. [ABSTRACT FROM AUTHOR]

The rural and monumental architecture of Northern Spain gives testimony of the wide-ranging constructive possibilities of traditional gypsum for exterior and structural applications. However, today, gypsum is only used for finishing purposes. By combining a bibliographic review with local visits/interviews and experimental gypsum calcinations, we were able to document traditional processing methods and analyze the factors responsible for the decline of exterior and structural gypsum use. Obtained results are also valid for other European countries and contribute to a better understanding of the technical peculiarities of traditional gypsum, hopefully reviving traditional processing techniques to produce compatible and sustainable conservation materials. [ABSTRACT FROM AUTHOR]

Medieval tileries, their mode of production and development are still very poorly understood. This research update combines historic and recent excavation data, along with documentary evidence to suggest that there may have been a rare example of a commercial tilery, operating independently of the church or crown in the Chichester region (UK), as early as the thirteenth century. This kiln site produced utilitarian roof tile, potentially for distribution across the region, including to sites of low status. The industry appears to have moved out of the city of Chichester to the hinterland in the late medieval period.

Traditional technologies for clay brick burning are often confronted with firing problems. The produced brick is of poor quality due to poor combustion inside the kiln. So that, cooking plays an important role because it determines the quality of the final product. Therefore, this work presents a transient computational fluid dynamic (CFD) study of firing clay bricks in the traditional oven. The heat transfer modeling in the furnace mainly is made from hydrodynamic equations and combustion reactions. Therefore, numerical simulation is done using ANSYS-Fluent software, using the standard k-ε turbulence model and the Eddy Dissipation turbulent combustion model. The results focused on the flow field, evolution of temperature, and O2 mass fraction to verify the combustion process inside the kiln. The results show that the kiln reaches the maximum temperature is in order of 900 °C and therefore verification process occurs. Moreover, the results revealed that the O2 mass fraction has the highest values at the inlet and it decreases gradually inside the kiln which gives good evidence about combustion process propagation.

The paper presents the database Cretan Institutional Inscriptions, which was created as part of a PhD research project carried out at the University of Venice Ca’ Foscari. The database, built using the EpiDoc Front-End Services (EFES) platform, collects the EpiDoc editions of six hundred inscriptions that shed light on the institutions of the political entities of Crete from the seventh to the first century BCE. The aim of the paper is to outline the main issues addressed during the creation of the database and the encoding of the inscriptions and to illustrate the core features of the database, with an emphasis on the advantages deriving from the combined use of the TEI-EpiDoc standard and of the EFES platform.

The kilning of malt occurs at different temperatures, depending on the desired color and aromas. Higher temperatures applied during kilning can be involved in polycyclic aromatic hydrocarbons (PAHs) formation in malt. PAHs are undesirable and designated as health hazards, it is important to quantify and qualify them in different malts. Since the European Food Safety Authority (EFSA) gave strict recommendations about PAHs in different foods, but omitted malt as a potential hazardous raw material that can cause health damage to beer consumers, the aim of this investigation was to assess the presence of 16 PAHs (naphthalene (Nap), acenaphthylene (Anl), acenaphthene (Ane), fluorene (Flu), anthracene (Ant), phenanthrene (Phen), fluoranthene (Flt), benz[a]anthracene (BaA), pyrene (Pyr), chrysene (Chry), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), dibenz[a,h]anthracene (DahA), benzo[ghi]perylene (BghiP), and indeno[1,2,3-cd]pyrene (InP)) in different, commercially available malts (amber, black, pilsner, and cara-120). The results showed that PAHs are present in different malts, with some in high amounts (BaA in black malt was 737 µg/kg). Minimal levels of BaA were detected in the amber malt, 60.53 µg/kg. The PAH4 (BaP, BaA, BbF, and Chry) sums are identical to the BaA concentrations in all malts and greatly exceed the EFSA prescribed levels for PAH4 in processed cereal-based foods (1 µg/kg). [ABSTRACT FROM AUTHOR]

Hybrid buildings are not a modern invention. In the case of certain types of buildings in historical production facilities, a degree of inseparable fusion of static buildings and dynamic mechanics can be detected. This goes far beyond the multifunctional use of a room and also includes constructional and architectural design to the same extent. They are not simply rooms or buildings in which machines for the production of an item or a product are installed, but the room, or the building, itself, is the "machine", or at least an essential part of it. Or is the machine the building? This relationship will be explained using the example of historical oast houses. For this type of building, architectural development from an integrated yet barely perceptible component to a free-standing solitary building can be demonstrated over a period of around 80 years. It is not clear which part is the building and which is the production technology. These two main components have become an indissoluble unit, making the oast house a real hybrid. A hibrid épületek nem a jelen kor találmányai. A történeti gyártólétesítmények egyes épülettípusainál az épület és a gépek már-már feloldhatatlan egymásba fonódása figyelhető meg. Ez a jelenség jelentősen túlmutat a többcélú helyiségeken, és egyaránt jellemző a szerkezeti és az építészeti kialakításra is. Itt már nem olyan épületekről beszélhetünk, amelyekben gépek vannak felállítva, hanem maga az épület válik a „géppé", illetve annak szétválaszthatatlan részévé. Vagy a gép maga az épület is egyben? A fenti összefüggés bemutatása a történeti aszalók példáján keresztül történik. Közel 80 év leforgása alatt az épületben korábban alig látható berendezés szabadon álló épületté fejlődik, amelyben már-már meghatározhatatlan, hogy melyik rész tartozik még magához az épülethez és melyik rész már a gyártástechnika. A két fő komponens szétválaszthatatlan egységet alkot, vagyis az aszaló igazi hibriddé fejlődik. Hybride Gebäude sind keine Erfindung der Neuzeit. Bei bestimmten Bautypen historischer Produktionsstätten ist eine Größenordnung der Durchdringung von statischem Gebäude und dynamischer Mechanik festzustellen, die nicht aufzulösen ist. Dies geht weit über die multifunktionale Nutzung eines Raumes hinaus, und umfasst in gleichem Maße auch die Konstruktion und architektonische Gestaltung. Es sind keine Räume, oder Gebäude in denen Maschinen zur Produktion eines Gegenstandes oder einer Ware aufgestellt werden, sondern der Raum, oder das Gebäude selbst ist die „Maschine", oder zumindest ein wesentlicher Teil von dieser. Oder ist die Maschine das Gebäude? Am Beispiel historischer Darren soll dieser Zusammenhang erläutert werden. Für diesen Gebäudetyp kann in einem Zeitraum von etwa 80 Jahren eine architektonische Entwicklung vom visuell kaum wahrnehmbaren und integrierten Bauteil zum freistehenden Solitär nachgewiesen werden. Dabei ist nicht eindeutig festzustellen, welcher Teil das Gebäude ist, und welcher die Produktionstechnik. Aus den beiden Hauptkomponenten ist eine unauflösbare Einheit geworden, womit die Darre zum echten Hybrid wird. [ABSTRACT FROM AUTHOR]

Тhe archaeological complex in Kosharna is located at 3 km to the southwest of the eponymous village in the areas Kajnanak dere and Koru Gjoldjuk. It consists of 2 tell-settlements and adjoining cemetery dated to the second half of Chalcolithic period. A clay feature was found within a hoard of ceramic vessels in the Chalcolithic cemetery. The situation was interpreted by the excavator and current author as a ceramic structure – depot for ceramic vessels, which have been used during the burial ceremonies. The hoard is related to the Late Copper Age and the Gumelnitsa culture. The current paper is a response to the article by Stilyan Ivanov offering reinterpretation of the feature with the hoard as a kiln for single firing of ceramics. The analysis focuses on four field observations and conclusions – the location, secondary burning, the presence of the vessels and the remains of a clay structure. The discovered feature is still without analogue in Balkan prehistory.

Marea/Northern Hawwariya is one of the largest and most important archaeological sites dating between the 3rd century BC and the 8th century AD located at Lake Mareotis in northern Egypt. Even though excavations have been carried out since the end of the 1970s, the settlement is still largely unexplored. To rectify this situation, non‐invasive research has been carried out on 21.5 ha of the site using a precise positioning system and magnetometer measurements. Exact topographic and magnetic maps were prepared based on the data that were obtained. Simultaneously, verification research were carried out, including archaeological excavations, registering surface findings and satellite image analysis. In the south‐eastern part of the site, electrical resistivity measurements were taken as well. This approach allowed for the identification of the densely built areas of the Byzantine and Early Islamic town. On the south‐western side, some magnetic anomalies were registered, following regular patterns with clear linear borders and surrounded by wetlands without clear signs of habitation. On the northern side, the settlement was limited by an artificial coastline, forming straight waterfronts made of stone blocks. As for the town itself, a 260‐m street with adjacent regular built‐up areas was discovered. This regularity points to an order of planning, at least for the Byzantine part of the settlement. Recording of large amplitude magnetic anomalies proves the presence of heavily burnt objects. They may be interpreted as remains of kilns, perhaps used to manufacture amphorae, glass vessels and lime. Electrical resistivity measurements in the south‐eastern part of the site localized cavities in the natural limestone rock uplift. These may have been rock‐cut tombs. Multidisciplinary, non‐invasive research in Marea/Northern Hawwariya allowed for the quick generation of new knowledge on the topography of the site, significantly enriching information on its form and the functions of its various parts. [ABSTRACT FROM AUTHOR]

Copyright of Refractories / Naihuo Cailiao is the property of Naihuo Cailia (Refractories) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Goal: Retrofit technology has been suggested for the reduction of CO2 emission in cement manufacturing but the economic justification of this retrofit technology is rarely or not available. This research study aimed to evaluate the beneficial value of retrofit technology aimed at reducing CO2 emission in a wet process cement plant. Design / Methodology / Approach: Engineering Economic and cost estimation techniques were used to evaluate the overall annual cost of combination of retrofit technology. The overall annual cost of retrofit technology was determined in terms of capital cost, operation and maintenance cost and energy cost savings of retrofit. Results: The best strategy to reduce CO2 emission is the combination of adjustable speed drive for kiln; kiln drive efficiency improvement for kiln and process control and management system for kiln at 6% reduction target, giving a cost savings of $520,836 on retrofit for 10 years and 1.41% reduction in total cost. Limitations of the investigation: Getting adequate plant data in Nigeria was a constraint during the research. Practical implications: The results presented if implemented by Cement plant operators will ensure reduction in the CO2 emission and government can enforce Cement plant operators to adhere to strict environmental and safety regulations while litigations and sanctions can be employed to implements this policy. Originality / Value: The study established economic justification of retrofit technology for CO2 emission reduction before eventual implementation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Roman Pottery Studies is the property of Casemate Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)