scholarly journals Energy evaluation of clay firing process and combustion gases in an intermittent kiln

2022 ◽  
Vol 2163 (1) ◽  
pp. 012005
Author(s):  
G Guerrero Gómez ◽  
N Afanador Garcia ◽  
C Nolasco Serna
Keyword(s):  
Ceramic Materials ◽  
Average Concentration ◽  
Heat Losses ◽  
Firing Process ◽  
Heat Accumulation ◽  
Combustion Gases ◽  
Energy Evaluation ◽  
Pollutant Gases ◽  
Reducing Energy ◽  
Residual Heat

Abstract The recording of temperatures in different positions in the firing process in an intermittent kiln to produce ceramic materials is presented, which led to the energy evaluation, determining the heat used for the clay firing process and the heat losses. In addition, a study of the emissions of pollutant gases released into the environment was carried out, as stipulated in the protocol of control, and monitoring of stationary source. In the energy balance, large energy losses were detected in heat accumulation in the masonry of 7.20×106 KJ of the energy supplied, representing 16.99%, and in the kiln walls of 5.20×10 KJ, representing 12.17%. As a result, it is necessary to make constructive and operative changes in the operation of the kilns, which will lead to the recovery of residual heat in the use of drying of parts, drying, and preheating of combustion air, reducing energy consumption and emissions of pollutants into the atmosphere. The average concentration of particulate matter released into the environment was 1056.60 mg/m3, 422% higher than the standard, affecting people’s health.

scholarly journals Recording of temperatures and heat accumulation in masonry in a continuous kiln used to produce ceramic materials

2021 ◽  
Vol 2073 (1) ◽  
pp. 012011
Author(s):  
G Guerrero Gómez ◽  
N Afanador García ◽  
R J Gallardo Amaya
Keyword(s):  
Virtual Instrument ◽  
Ceramic Materials ◽  
Firing Process ◽  
Ceramic Fibers ◽  
Fuel Temperature ◽  
Heat Accumulation ◽  
Combustion Chambers ◽  
Low Efficiency ◽  
Temperature Constant ◽  
Combustion Processes

Abstract In Ocaña, Colombia, a traditional ceramic industry has been developed using low efficiency kilns without controls in the combustion processes, which generate large heat losses. As a result, it was necessary to implement a virtual instrument to monitor temperatures in the firing process. For the study, a continuous Hoffman kiln, and the temperature acquisition was carried out in two combustion chambers and lasted twenty-four hours. In the kiln firing process, the energy supplied due to coal combustion was 22198×106 KJ, while the heat accumulated in the kiln roof, walls and floor was 14452.6×106 KJ, 1085.71×106 KJ and 164.72×106 KJ respectively. The total heat stored in the masonry was 15703.03×106 KJ, representing 70.73 % of the energy supplied. Due to the material used in the construction of the kiln, the accumulated heat is high, and it is necessary to implement coatings using ceramic fibers on the kiln walls, keeping the temperature constant in the firing process and leading to a decrease in heat accumulation of about 20 %. Also, air, fuel, temperature, and pressure injection systems should be implemented.

Residual heat generated during laser processing of CFRP with picosecond laser pulses

2018 ◽  
Vol 7 (3) ◽  
pp. 157-163
Author(s):  
Christian Freitag ◽  
Leon Pauly ◽  
Daniel J. Förster ◽  
Margit Wiedenmann ◽  
Rudolf Weber ◽  
...  
Keyword(s):  
Laser Pulse ◽  
Heat Affected Zone ◽  
Laser Processing ◽  
Picosecond Laser ◽  
Theoretical Models ◽  
Laser Pulses ◽  
Groove Depth ◽  
Interaction Zone ◽  
Heat Accumulation ◽  
Residual Heat

Abstract One of the major reasons for the formation of a heat-affected zone during laser processing of carbon fiber-reinforced plastics (CFRP) with repetitive picosecond (ps) laser pulses is heat accumulation. A fraction of every laser pulse is left as what we termed residual heat in the material also after the completed ablation process and leads to a gradual temperature increase in the processed workpiece. If the time between two consecutive pulses is too short to allow for a sufficient cooling of the material in the interaction zone, the resulting temperature can finally exceed a critical temperature and lead to the formation of a heat-affected zone. This accumulation effect depends on the amount of energy per laser pulse that is left in the material as residual heat. Which fraction of the incident pulse energy is left as residual heat in the workpiece depends on the laser and process parameters, the material properties, and the geometry of the interaction zone, but the influence of the individual quantities at the present state of knowledge is not known precisely due to the lack of comprehensive theoretical models. With the present study, we, therefore, experimentally determined the amount of residual heat by means of calorimetry. We investigated the dependence of the residual heat on the fluence, the pulse overlap, and the depth of laser-generated grooves in CRFP. As expected, the residual heat was found to increase with increasing groove depth. This increase occurs due to an indirect heating of the kerf walls by the ablation plasma and the change in the absorbed laser fluence caused by the altered geometry of the generated structures.

Central Ventilation System with Heat Recovery as One of the Measures to Upgrade Energy Efficiency of Historic Buildings

2014 ◽  
Vol 633-634 ◽  
pp. 1077-1081 ◽  
Author(s):  
Viktor Pukhkal ◽  
Nikolay Vatin ◽  
Vera Murgul
Keyword(s):  
Heat Recovery ◽  
Natural Ventilation ◽  
Ventilation System ◽  
Heat Losses ◽  
Historic Buildings ◽  
Existing Buildings ◽  
Apartment Building ◽  
Thermal Shield ◽  
Saint Petersburg ◽  
Reducing Energy

Improving thermal shield in buildings and reducing energy consumption have become major problems to be solved for the recent decades. Natural ventilation accounts for nearly half of heat losses in existing buildings. A controlled heat recovery ventilation system makes it possible to reduce irrational heat losses and improve microclimatic comfort. A typical historic residential apartment building constructed before industrial times in Saint-Petersburg is subject of this article. Options of centralized controlled heat recovery ventilation systems for old historic apartment buildings in Saint-Petersburg are suggested in this article.

scholarly journals Energy lost in endothermic reactions in the production of clay blocks in a continuous kiln

2021 ◽  
Vol 2118 (1) ◽  
pp. 012018
Author(s):  
G Guerrero Gómez ◽  
N Afanador García ◽  
C Nolasco Serna
Keyword(s):  
Virtual Instrument ◽  
Respiratory Diseases ◽  
Ceramic Materials ◽  
Firing Process ◽  
Brick Kiln ◽  
Coal Quality ◽  
Reducing Gas ◽  
Record Data ◽  
Endothermic Reactions ◽  
Acute Respiratory Diseases

Abstract In Ocaña, Norte de Santander, Colombia, the production of ceramic materials is done in a traditional and empirical manner, generating heat losses, low productivity and product quality, and increased emissions of polluting gases into the environment. A virtual instrument for temperature data acquisition was developed and the firing process was monitored in two loading doors of a Hoffman kiln. 29040 blocks were produced, and 1370.76 kg of pulverized charcoal were consumed. The firing process lasted sixty-two hours and the virtual instrument was programmed to record data every 5 minutes. The energy supplied to the brick kiln was 340.16x106 kJ and the heat due to loading of the products and heat lost in the endothermic reactions of the clay was 107.71x106 kJ and 105.71x106 kJ respectively, representing 31.66% and 31.08% of the energy supplied. The results have made it possible to establish trends in the temperatures and energy consumed in the endothermic reactions in the clay. This will allow the implementation of coal quality and grinding procedures, increasing energy efficiency, and reducing gas emissions into the environment, thus avoiding acute respiratory diseases.

scholarly journals Latvijas minerālās izejvielas eko-keramikas izstrādei

2018 ◽  
Vol 35 ◽  
pp. 62-85
Author(s):  
Gaida Sedmale ◽  
Māris Rundāns ◽  
Mārtiņs Randers ◽  
Ingunda Šperberga ◽  
Andris Cimmers
Keyword(s):  
High Temperature ◽  
Ceramic Material ◽  
Gas Phase ◽  
Phase Formation ◽  
Raw Materials ◽  
Ceramic Materials ◽  
Firing Process ◽  
Mineral Raw Materials ◽  
Technological Processes ◽  
Insight Into

Darbā dots ieskats par iespējām izmantot Latvijas minerālās izejvielas kā bāzi vai  piedevu  keramikas  materiālu  (eko-materiālu)  izstrādei ar dažādu pielietošanas aspektu, to skaitā parādīt iespēju šo materiālu ieguves tehnoloģisko procesu optimizēšanai virzībā uz to apdedzināšanas temperatūras samazināšanu, līdz ar to reducējot kaitīgu gāzveida izmešu nonākšanu vidē. Parādīti darbu rezultāti laika periodā no 2007. g. līdz 2017. g. Tiek apskatīti un analizēti sekojoši pētījumi:neapstrādāta māla pielietošana atkritumu deponēšanas vietu noblīvēšanai;daļēji dehidratizēta māla pielietošana Cr3+, Cr6+, Zn2+ un Cu+ jonu sorbcijai, kas veidojas galvanisko procesu notekūdeņos; poru saturošas augsttemperatūras keramikas izstrāde no jauktiem izejvielu maisījumiem, kas nodrošina pietiekamu gāzveida fāzes izveidošanos keramikas apdedzināšanas procesā, veidojot poras, lai pielietotu par filtrēšanas/attīrīšanas materiālu;illīta māla piedevu izmantošana, lai pazeminātu augsttemperatūras blīvas keramikas saķepināšanas/apdedzināšanas temperatūru, iegūstot ilgspējīgu mehāniski un termiski izturīgu produktu; kā arī tehnoloģiskie procesi, kas nodrošina porainas, siltumu izolējošas keramikas materiāla ieguvi pie pazeminātām temperatūrām (ģeopolimēru metode).Mineral Raw Materials of Latvia for Development of Eco-CeramicsThe paper gives an insight into the possibilities to use Latvian mineral raw materials as a base or additives for the development of ceramic materials (eco- materials) with different application aspects, including showing the possibility of optimizing the technological processes of these materials towards the reduction of their firing temperature, thereby reducing the release of harmful gaseous effluents into the environment.The results of the works that are reported in the period were obtained from  2007 to 2017. The following studies are reviewed and analyzed: the use of untreated clay for the sealing of waste deposits; the use of partly dehydrated clay for sorption of Cr3+,6+, Zn2+ and Cu2+, which have formed in galvanic processes; the development of porous high temperature ceramics from mixes  of mineral raw materials and synthetic additives that provide a sufficient gas phase  formation in the firing process and consecutively to form pores in obtained ceramic material; the use of illite clay additives to reduce the temperature of sintering of high temperature dense mechanical and thermally durable ceramics, as well as technological processes that ensure the production of porous, heat-insulating ceramic materials at reduced temperatures (geopolymer method).

scholarly journals Patents Analysis of Thermal Bridges in Slab Fronts and Their Effect on Energy Demand

Energies ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 2222 ◽  
Author(s):  
David Bienvenido-Huertas ◽  
Juan Antonio Fernández Quiñones ◽  
Juan Moyano ◽  
Carlos E. Rodríguez-Jiménez
Keyword(s):  
Energy Demand ◽  
Heat Losses ◽  
Global Energy ◽  
Thermal Transmittance ◽  
Thermal Bridge ◽  
Energy Behaviour ◽  
Current Scenario ◽  
Thermal Bridges ◽  
Pollutant Gases

Nowadays, the building sector is one of the main sources emitting pollutant gases to the atmosphere due to its deficient energy behaviour. Among the elements of the envelope, the thermal bridges are where the heat losses and gains mainly occur, depending on the season of the year. To reduce the effect of the thermal bridges, there are different patented technologies which give provide solutions. In this paper, the thermal behaviour of five patented slab front (slab-façade) thermal bridges are analysed in a case study located in the south of Spain. Moreover, the influence of the thermal bridge on the energy demand from the building analysed was evaluated, both in the current scenario and future ones (2020, 2050 and 2080). The results reveal that the use of the patents in slab fronts can mean reductions by up to 95.74% in the linear thermal transmittance. Likewise, due to the improvement of the thermal bridge of slab fronts by using the patented designs which offered the best features, a savings in the global energy demand for heating higher than 18% as well as a savings in the global energy demand for cooling higher than 2.80% could be achieved in all the time scenarios considered.

scholarly journals Investigation of Thermal Behavior of 3D PET Knits with Different Bioceramic Additives

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1319
Author(s):  
Audronė Sankauskaitė ◽  
Vitalija Rubežienė ◽  
Diana Kubilienė ◽  
Aušra Abraitienė ◽  
Julija Baltušnikaitė-Guzaitienė ◽  
...  
Keyword(s):  
Thermal Behavior ◽  
Far Infrared ◽  
Ceramic Materials ◽  
High Heat ◽  
Heat Accumulation ◽  
Sem Images ◽  
Coating Methods ◽  
Coated Fabrics ◽  
Ceramic Compounds ◽  
3D Pet

The purpose of this study is to investigate the thermoregulatory properties of polyethylene terephthalate (PET) 3D knitted materials with bioceramic additives which are highly absorbing far-infrared (FIR) radiation. Ceramic materials are well-known and useful for thermal insulation applications. In order to compare different types of ceramic additives and coating methods for their incorporation into textile, several types of ceramic compounds with heat-retaining function were selected: germanium (Ge), aluminum (Al) and silicon (Si) additives were applied by impregnation in squeezing padder and titanium (Ti) by the screen printing method. The thermoregulatory properties (thermal resistance, heat-retaining effectiveness and air permeability) of 3D PET knits with bioceramic additives were estimated. In this study scanning electron microscopy (SEM) images were used to analyze the morphology of coated fabrics, X-ray fluorescence spectroscopy (XRF) analysis was applied to evaluate the number of minerals with high heat capacity in each formulation used for treatment. The knits coated with a formulation containing Ti ceramic additives demonstrated the most effective thermal behavior. Furthermore, better heat accumulation effectiveness of Ti ceramics containing knits was confirmed by Fourier transform infrared spectroscopy (FTIR) analysis. It was also determined that 3D knitted fabric with Ti ceramic additives showed the highest emissivity among tested samples and the implication is that this sample radiates its energy more efficiently than others.

Compositional homogeneity of ferroelectric (Pb,La)(Ti,Zr)O3 thick films

2003 ◽  
Vol 18 (2) ◽  
pp. 515-523 ◽  
Author(s):  
S. Bernik ◽  
R.B. Marinenko ◽  
J. Holc ◽  
Z. Samardžija ◽  
M. Čeh ◽  
...  
Keyword(s):  
Ceramic Materials ◽  
Processing Parameters ◽  
Beam Line ◽  
Firing Process ◽  
Line Profiles ◽  
Pt Electrode ◽  
Wavelength Dispersive Spectroscopy ◽  
X Ray ◽  
The Matrix ◽  
Compositional Homogeneity

Quantified wavelength dispersive spectroscopy (WDS) x-ray element maps were used to characterize active (Pb,La)(Ti,Zr)O3 (PLZT) layers on Pt/PLZT/Al2O3 substrates, one fired at 1050 °C and the other at 1150 °C. In the layer fired at 1050 °C, randomly distributed micrometer-sized compositional irregularities were observed as La-rich regions that were in most cases enriched also with Ti and deficient in Pb and Zr compared to the matrix. Such compositional imperfections were not observed in the PLZT layer fired for the same duration at 1150 °C. The level of microheterogeneity for all elements in the specimen fired at 1150 °C and for Pb, Ti, and Zr in the specimen fired at 1050 °C was below 1% relative at confidence level of 99% while for La it was as much as 2.5% relative. In point-beam line profiles across the active layer starting from the Pt electrode toward the outer surface of the cross-section of the PLZT film, the Pb concentration decreased continuously in both samples, confirming the importance of providing a properly equilibrated partial pressure of Pb around the sample during the entire firing process. Better dielectric and ferroelectric characteristics of the specimen fired at 1150 °C compared to the sample fired at 1050 °C were attributed to the differences in compositional heterogeneity between these samples. The study of the micro-compositional characteristics of these ceramic materials with quantitative WDS mapping has contributed to the optimization of processing parameters and hence to the understanding of the properties of ferroelectric PLZT materials.

Innovative Directions for the Use of Drill Cuttings in the Production of Ceramic Materials on the Basis of Milentevoy Clay is a Promising Direction for a Green Economy.

2017 ◽  
Vol 21 (3) ◽  
pp. 26-31 ◽  
Author(s):  
V.Z. Abdrakhimov ◽  
E.S. Abdrakhimova
Keyword(s):  
Building Materials ◽  
Ceramic Materials ◽  
Raw Material ◽  
Green Economy ◽  
Firing Process ◽  
Sintering Behavior ◽  
Drilling Mud ◽  
Drill Cuttings ◽  
Waste Products ◽  
Traditional Natural

As an additive to reduce the drying of the bricks were used drill cuttings produced during oil production. In addition, drilling mud has a high calorific value, so this component it is advisable to use as burnable additives. The purpose of the burnable additives – intensify the firing process, to improve the sintering behavior of the masses and thereby to increase the strength of products and to reduce the density. As a binder, to obtain a ceramic material was used mislava clay, which is a waste of oil shale. The production of ceramic materials from waste products without the use of traditional natural materials contributes to the development of "green" economy. Given that currently traditional natural raw material resources in Russia and other CIS countries are exhausted, involving waste products in an industrial revolution will make highquality ceramic materials. The use of waste products in the production of building materials promotes recycling , environmental protection and reducing environmental impact in the regions.

Examination of Fracture Interfaces in Silicon Nitride

1975 ◽  
Vol 33 ◽  
pp. 60-61
Author(s):  
Nancy J. Tighe
Keyword(s):  
Silicon Nitride ◽  
Grain Boundary ◽  
Crack Growth ◽  
Subcritical Crack Growth ◽  
Slow Crack Growth ◽  
Ceramic Materials ◽  
Grain Boundary Sliding ◽  
Boundary Phase ◽  
Turbine Engines ◽  
Boundary Sliding

Silicon nitride is one of the ceramic materials being considered for the components in gas turbine engines which will be exposed to temperatures of 1000 to 1400°C. Test specimens from hot-pressed billets exhibit flexural strengths of approximately 50 MN/m2 at 1000°C. However, the strength degrades rapidly to less than 20 MN/m2 at 1400°C. The strength degradition is attributed to subcritical crack growth phenomena evidenced by a stress rate dependence of the flexural strength and the stress intensity factor. This phenomena is termed slow crack growth and is associated with the onset of plastic deformation at the crack tip. Lange attributed the subcritical crack growth tb a glassy silicate grain boundary phase which decreased in viscosity with increased temperature and permitted a form of grain boundary sliding to occur.

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