Type Of Oven Research Articles

Effect of Curing Condition on Superhydrophobic Surface for 7075Al

A simple curing condition was introduced to fabricate a stable superhydrophobic surface on aluminum. In this method, hierarchical structure by low energy hydrophobic groups (trichloromethylsilane) are combined and after annealing in a radiative type oven, exhibit superhydrophobic properties with water contact angle of more than 160° and water sliding angle of less than 3°. Scanning electron microscopy (SEM) images of the resulting surface show that the surface is covered by various sizes of submicroscopic filaments, which become more regular and adhesive when curing in the radiative oven. It also indicates that the stability and durability of the structure significantly improved through this heating process.

Wood consumption and analysis of the bread baking process in wood-fired bakery ovens

Combustion of biomass in small-scale furnaces is used widely in different applications. The technology used is often “fixed grate” combustion in small batch furnaces. The efficiency of such a furnace is often low, which results in a high environmental impact. The aim of this work was to analyse the performance of the existing wood-fired bakery ovens that can be used to improve the efficiency. The data collected from 15 semi-direct and 3 indirect bakeries consisted of: the dimensions of the oven, the temperature profiles of the combustion chamber and the baking oven, the baking time and the bread quality. It was found that as much as 60 tons/day of green wood are consumed in the bread baking process in the area investigated. Two types of bakery ovens are used most commonly: indirect and semi-direct. The specific consumption was found to be 0.55 and 0.90 kg of wood per kg of wheat flour baked for the indirect and the semi-direct respectively. The analyses of the bread baked show that the variation of the temperature profile during the baking process influences the quality of the bread produced.

Microwave freeze-thaw treatment of cytotoxic and hazardous injectable drugs: a review of the literature from 1980 to 2011

BackgroundMicrowave freeze-thaw treatment (MFTT) of injectable drugs can support the development of centralised intravenous admixtures services (CIVAS).PurposeThe aim of the review was to collect information and results about MFTT of...

Thermal energy management in the bread baking industry using a system modelling approach

Energy usage in bread ovens is analysed using a generic methodology applicable to all types of mass-production tunnel ovens. The presented methodology quantifies the energy required to bake the dough, and to conduct a detailed analysis of the breakdown of losses from the oven. In addition, a computational fluid dynamics (CFD) optimisation study is undertaken, resulting in improved operating conditions for bread baking with reduced energy usage and baking time. Overall, by combining the two approaches, the analyses suggest that bake time can be reduced by up to 10% and the specific energy required to bake each loaf by approximately 2%. For UK industry, these savings equate to more than £0.5 million cost and carbon reduction of more than 5000 tonnes CO2 per year.

Effects of Additives for Warm Mix Asphalt on Performance Grades of Asphalt Binders

Abstract Laboratory tests were carried out on a neat asphalt binder and a styrene-butadiene-styrene (SBS) asphalt binder containing Sasobit and Aspha-min as warm mix asphalt (WMA) additives to quantitatively evaluate the effects of the additives on the continuous grading temperatures and grades of asphalt binders in the framework of the performance grading system. Test results and data analyses indicate that the significances of the effects of WMA additives depend on the asphalt binder type, additive type, additive content, and rolling thin film oven (RTFO) aging temperature. The wax-type additive Sasobit has a stiffening effect on the grading temperatures. At typical 3 % content, the upper temperatures can be increased by up to 13.5 °C, the lower temperatures can be increased by up to 6.9 °C, and the intermediate temperatures can be increased by up to 5.0 °C. In the commonly used content range, the zeolite-type additive Aspha-min has little effects on the upper, lower, and intermediate grading temperatures. Although there is a special case, in which the upper grading temperature increase is canceled out by 3.8 °C, the reduction in RTFO aging temperature from 163 °C to 133 °C does not generally result in notable changes in the grading temperatures.

Innovative Semi-Analytical Methodology to Predict Automobile Body Temperature Distribution in the Curing Ovens

In automobile painting industries, new automobile body products frequently should be tested in order to determine the actual thermal behavior of a paint curing process before starting mass production. During the hardening processes of dipped paint coating, applied in the electrophoretic enameling process, or top paint coating, applied in the final coating process, the automobile body must be warmed up according to the specific paint manufacturer curve. Consequently, prediction of car body temperature during the curing process may be vital in the design and performance analysis of the paint ovens. Numerical simulation of these processes may reduce expensive and time-consuming experimental procedures. In this research, a novel semi-analytical approach has been developed to predict the car body temperature during the curing process. Considering energy balance for each part of the body, a set of nonlinear differential equations has been extracted, which are related to the oven type and the heating zone. These equations may be solved numerically to find the transient temperature profile of the car body, provided that the required parameters are measured through experimental investigation. The results show that the present model predictions are in reasonably good agreement with experimental data, and this can be used as a robust efficient approach to distinguish overall thermal behavior of the car body during curing process. This research and its results may be useful in getting better understanding of the heat transfer mechanisms in the paint curing ovens and in optimizing their structures.

Estudio arqueométrico y evaluación del deterioro de los materiales cerámicos de la fachada de la iglesia de Santa Maria del Carmine (Pavía, Italia)

We performed an archaeometric study of the ceramic materials from the facade of the church of Santa Maria del Carmine in Pavia (Italy). We obtained useful information about the firing temperatures, the provenance of raw materials and the type of oven used. The ceramics used in the facade are mineralogically rich in quartz, feldspar and phyllosilicates, and newly formed calcium silicate phases were detected in some samples. Microtextural observations revealed the presence of incipient reaction rims, phyllosilicate sintering and partial vitrification of the matrix. Ceramics show high porosity (32 to 45%) and pore sizes of between 0.4 and 1.3 µm. Our study of the different types of decay collected on the facade of the church (green and black patinas and efflorescences) revealed the presence of gypsum, whewellite, thenardite and moolooite.

Resfriamento rápido de fornos de carbonização

A importância dos recursos naturais renováveis no mundo é crescente. No processo produtivo do carvão vegetal, é possível aumentar a eficiência global de transformação da lenha de eucalipto em carvão vegetal. Em processos industriais, o tempo de resfriamento da massa de carvão varia de 6 a 8 dias, com a utilização do resfriamento natural da massa de carvão, sendo que a temperatura para a abertura dos fornos de carbonização é de cerca de 60 ºC, e a temperatura inicial da massa de carvão em torno de 480 ºC. Sendo assim, foi estudado um sistema de resfriamento de fornos de carbonização utilizando injeção de vapor de água, com o objetivo de reduzir o tempo de resfriamento do carvão. Foram construídos um forno tipo contêiner em escala de laboratório, de dimensões iguais a 3,0 x 2,0 x 1,6 m e um sistema de queima dos gases provenientes da carbonização da lenha, instrumentado com termopares tipo K e um sistema de aquisição de dados, nos Laboratórios de Energia na Agricultura e de Pré-Processamento de Produtos Agrícolas do Departamento de Engenharia Agrícola da Universidade Federal de Viçosa, Viçosa, Minas Gerais. Foi utilizada também uma caldeira para geração de vapor para o resfriamento rápido do forno. O tempo de resfriamento da massa de carvão foi reduzido em cerca de dois dias pela injeção de vapor de água, quando comparado com o processo de resfriamento natural.

Two-dimensional CFD modeling and simulation of crustless bread baking process

A special type of baking oven was developed where crustless bread was made by gently baking the dough at controlled temperature by spraying water at prefixed intervals on the surface of the dough. In this study, a two-dimensional (2D) CFD model for crustless bread during baking has been developed to facilitate a better understanding of the baking process. Simultaneous heat and mass transfer from the bread during baking was successfully simulated. It was found that core temperature of the bread reached at 95 °C at the end of baking where as moisture of the bread satisfies the normal bread quality. The model can be successively applied to study the unsteady heat and mass transfer from the crustless bread during baking.

Distribution of the heat transfer coefficient in convection reflow oven

Nowadays reflow ovens apply forced convection heating with nozzle-matrix blower system which generates numerous heater gas streams. In these types of ovens the heat transfer coefficients of the gas streams determine mainly the efficiency of heating. In this paper a measurement method is discussed which can determine the heat transfer coefficient distribution under the nozzle-matrix of a convection reflow oven. During the experiments, temperature changes have been measured and the heat transfer coefficient has been calculated using the heat equation of the investigated reflow oven. In the first step, the heat transfer coefficient of the heater gas streams has been studied under the nozzle-matrix in function of height. In the second step, the heating efficiency of the nozzle-lines has been compared and the distribution of the heat transfer coefficient has been calculated. The results are confirmed by a theoretical model. It is also presented that how the contamination of the nozzles affects the heating efficiency of the reflow oven. This measuring method can be useful for monitoring the operation of the reflow oven, soldering failure prediction and measuring input parameters of thermal modeling.

The effects of xanthan and guar gums on staling of gluten‐free rice cakes baked in different ovens

SummaryThe objective of this study was to determine the effects of different concentrations of xanthan and guar gums and their blends on staling of gluten‐free rice cakes baked in microwave‐infrared combination oven (MW–IR) and to compare the cakes with conventionally baked ones. Gums were added at concentrations of 0.3% and 1.0%. For preparation of gum blend, 0.5% xanthan gum was mixed with 0.5% guar gum. In order to understand the staling behaviour of cakes, cakes were stored at 22 ± 2 °C for 120 h. Xanthan‐guar gum blend decreased hardness, weight loss, retrogradation enthalpy and the change in setback viscosity values of cakes during storage for both types of ovens as compared to control formulation. It was found that oven type was a significant factor in affecting staling parameters of gluten‐free cakes.

Proposal of a Novel Multifunctional Energy System for Cogeneration of Coke, Hydrogen, and Power

This paper proposes a novel multifunctional energy system (MES), which cogenerates coke, hydrogen, and power, through the use of coal and coke oven gas (COG). In this system, a new type of coke oven, firing coal instead of COG as heating resource for coking, is adopted. The COG rich in H2 is sent to a pressure swing adsorption (PSA) unit to separate about 80% of hydrogen first, and then the PSA purge gas is fed to a combined cycle as fuel. The new system combines the chemical processes and power generation system, along with the integration of chemical conversion and thermal energy utilization. In this manner, both the chemical energy of fuel and thermal energy can be used more effectively. With the same inputs of fuel and the same output of coking heat, the new system can product about 65% more hydrogen than that of individual systems. As a result, the thermal efficiency of the new system is about 70%, and the exergy efficiency is about 66%. Compared with individual systems, the primary energy saving ratio can reach as high as 12.5%. Based on the graphical exergy analyses, we disclose that the integration of synthetic utilization of COG and coal plays a significant role in decreasing the exergy destruction of the MES system. The promising results obtained may lead to a clean coal technology that will utilize COG and coal more efficiently and economically.

Effect of Far-Infrared Oven on the Qualities of Bakery Products

ABSTRACT Interest in far-infrared ovens is driving the demands of baking industries for less time, less energy, and better quality. In this work, four baking products (bun bread, toast, pound cake, and sponge cake) were baked in a far infrared oven as well as in an electric oven to evaluate the effects of far-infrared radiation on qualities of baking products, including texture, volume, staling rate, and sensory evaluation. When the pound cake was baked in a far infrared oven, the batter temperature increased faster than pound cake baked in an electric oven. The hardness of sponge cake baked in a far-infrared oven after 7 days storage is softer than that of a sponge cake baked in an electric oven. There are no significant differences in the volume, water activity, staling rate, or sensory scores of baking products between these two types of baking ovens.

Product characterization of waste printed circuit board by pyrolysis

This paper is part of a project which studies pyrolysis as an alternative for recycling printed circuit board (PCB); the sample (2.0 cm × 2.0 cm) was pyrolyzed under nitrogen atmosphere, at 300, 400, 500, 600 and 700 °C in a tubular type oven, maintaining 30 min, and during the pyrolysis process the organic part is decomposed to pyro-oils and pyro-gases, which can be used as fuels or chemical material resources: the solid residues of about 75–80 wt.%, liquid yields of ∼9.0 wt.% and gas yields of 12–14 wt.%. No significant influence of temperature was observed over 500 °C, however, there was certainly influence under 500 °C in both volatile substance. The pyro-oils have fairly high gross calorific values (∼30 kJ/kg), mainly with aromatic and with oxygenated compounds. The pyro-gas is very rich in CO, CO 2, H 2, CH 4 and in small part of O 2; after being purged it can be combusted for the pyrolysis self-sustain. The tensile strength decreases about 35% at 773 K, while the impact and tear strength increases above 773 K, and then decreases along with the temperature increase. The strength changes can offer guidance for used as a replacement for virgin fibres in SMC manufacture. The residues are better laminated can be easily liberated for metals recovery.

Annealing Effect on Structural and Optical Properties of SnO2 Thin Films

Thin solid films of SnO2 were deposited by chemical vapor deposition (CVD) method on glass substrate at 450C and 2.5L/min.air flow rate. Deposited films were annealed at different temperature (200,300,400,500) C in air for 60 minutes. Structural properties have been studied for annealed and unannealed films. It was found that the films have polycrystalline structure with grain diameter(190-230)A depend on annealing temperature. And the crystal structure is tetragonal with lattice constants (a=b=4.782 ,c=3.233)A. Optical properties also studied for annealed and unannealed films using UV-visible spectroscopy. The transmission spectra showed higher transparency over the visible wave length region with maximum value (85-95)% depend on annealing temperature. Absorption edge energy is increased by annealing temperature from (3.93 to 4.1)eV while Optical energy gap is not affected by annealing and it is found to be (4.17)eV. Annealing Effect on Structural.... 100 Introduction Transparent, electrically conductive films have been prepared from a wide variety of materials. These include semiconducting oxides of tin, indium, zinc and cadmium; and metals such as silver, gold and titanium nitride .They have been used for many years as electrodes or resistive elements and applied to semiconductor devices as transparent gates on charge injection devices and charge coupled devices and as transparent barrier layers on solar cells[1]. The materials mostly used for such applications are tin oxide (SnO2), antimony-doped tin oxide and tindoped indium oxide. These films have been deposited by chemical vapour deposition, sputtering, evaporation and spraying [2]. Tin oxide films is the most used material because of its cheap raw material and highly existing in nature. It is characterized by a wide band gap and high electrical conductivity through the existing of O2 vacancies and interestial tin atoms in the crystal structure of the films and that is depend on method of deposition. Also it is a good transparent antireflecting material. Temperature stability and reproducibility of the film properties are important for device reliability. The films are exposed to heat during the preparation and operation of the device. This may cause structural changes which tend to either influence or degradation in most of the physical properties of the films. The effects of annealing are complex because of the variety of phenomenon that may observe. Many studies have been done on different transparent conducting oxides to find the effect of annealing on certain property of the films such as the refractive index (n), extinction index (k) and energy gap (Eg) for ZnO-SnO2 [3], resistivity and factor of merit for antimony-doped tin oxide[4], grain size, porosity and conductivity of tin-doped indium oxide[5] and many others [6,7,8,9]. In this study structural and optical properties of tin oxide films prepared by chemical vapour deposition are described. Also, the effect of annealing at different temperature in air on structural and optical properties of SnO2 thin films are studied including: grain size, lattice constant, transmission, optical energy gap and absorption edge. Experimental Detail The SnO2 thin films were prepared by CVD technique. Although this technique is well known and used by many workers[10], it still need some modification. We have modified and built this system in physics department, Education college, Mosul university, using the stannous chloride oxidation principle. The diagram of the experimental set-up used for SnO2 deposition is shown in Figure (1). Material used was SnCl2.2H2O (purity 99.99% supplied by Fluka Company). Films were Sanaa M. Al -Delaimy & Rajaa Abdulah Basheer 101 deposited on glass type (Gloim 1003/Italy) at 450°C substrate temperature and 2.5 L/min. gas flow rate. Fig.(1)Schematic Diagram of CVD System for SnO2 Films Deposition When the desired deposition factors were attained and stabilized the tin chloride was melted (melting point 247°C) using coil heater (350°C). The tin chloride vapour was driven through the reactor by maintaining an air flow. Air carries the SnCl2 vapour to form SnO2 film deposited on the hot substrate and the reaction takes place as follows: SnCl2 + O2  SnO2 + Cl2 After finishing the deposition the substrates were brought to room temperature inside the reactor. The deposition systems as well as the method have been described briefly in reference [11]. Some of the films were annealed in air by controllable electric oven type (Heraeus) at temperature (200,300,400,500)°C for 60 minutes, while the others were left without annealing. Structural properties were studied for annealed and unannealed films by X-ray diffraction (XRD) using a Philips X-ray diffractometer model (PW 1130). Source of radiation was Cu K (=1.5405 A°) and the scanning range of 2 was restricted to range (10-60)°. Perpendicular distance between adjacent crystal layers(dhkl) for each grain, Lattice constants (a=b, c) and grain diameter (D) of SnO2 film were calculated using the XRD pattern data and the following equations [12] : 2d hkl sin = n (1) 1 h k l ــ = ــ + ــ + ــ (2)

Reactive pozzolanas from rice husk ash: An alternative to cement for rural housing

This paper discusses the properties of rice husk ash samples produced from different types of field ovens to compare the performance of the ovens and to identify the most feasible method to produce a reactive pozzolana as an alternative to cement for building applications requiring lower strengths. Different types of ashes are produced and long-term strength of rice husk ash pozzolanas with lime or cement is investigated to suggest a sustainable affordable option in rural building applications, especially for rural housing in Kerala, a southern state of India.

Influence of asphalt cement type and oven type on asphalt retention capacity of paving geotextiles

This paper presents results from asphalt retention tests on geotextile products carried out in accordance with ASTM D 6140 . Three different geotextile products were used in combination with three different asphalt cements and two different types of oven (convection and forced air types). The results show important variations in retention values depending on the asphalt cement and the oven used. The current ASTM standard recommends using a convection oven. If the tests are carried out using a forced air oven, significantly lower values of asphalt retention capacity can be expected.

The Present Scenario of Non-Recovery Coke Ovens in India and Development of New Refractory Technology

The present status of coke making through the use of non-recovery coke ovens (NRCO) has been described. The main features and key characteristics of this type of oven have also been highlighted. The author's own contribution in development of innovative refractory technology for improved performance of this type of coke oven has also been elucidated.

The current development and latest achievements in cokemaking technology

The coke making industry has seen substantial technological development over the last decade. Conventional coke ovens (slot type ovens) with raw gas recovery have reached dimensions of more than 8 m height and 90 m 3 useful oven volume, boosting the capacity of a single battery to 1.3 Mt/y and the production of a single coke plant with one operating team to 2.6 Mt/y. At the same time, the emissions from batteries and gas treatment facilities have been reduced to the lowest amounts ever. A further increase in energy efficiency and environmental protection for conventional coke batteries is expected from the combustion of the hot raw gas with subsequent generation of electricity. The concept of a coke plant with direct combustion of the raw gas would omit the entire gas treatment plant and produce only coke and power. Aside from these achievements with conventional coke oven batteries, the non-recovery technology has also found acceptance. Coke plants of this type are in operation in the USA, Australia and India. One plant in the USA is a heat-recovery coke plant that produces power from the waste gas. Further improvements in plant efficiency and coke quality are achieved with stamping of the coal charge, which is now developed for non-recovery ovens, too.

Problems of the interlaboratory transferability of the measurement of the properties of a reversed-phase HPLC column

The reproducible transferability of HPLC methods between laboratories requires careful specification of the method, especially the temperature control of the column. The methods were examined in two international collaborative studies for a series of column characterisation tests for ODS-bonded phase columns. The results from 16 laboratories in the first study and 7 laboratories in the second study are analysed. Differences in the type of column oven can cause significant differences in the effective column temperature and hence in the relative retention times used to calculate hydrophobicity and shape selectivity. Water bath or water jackets gave markedly different results to air ovens at the same nominal temperature and were recommended as providing more transferable results. However, although the incoming eluent was controlled to be at the column temperature the efficiency of the separations were lower than in an air bath oven but were more repeatable.