scholarly journals Defibration mechanisms and energy consumption in the grinding zone – a lab scale equipment and method to evaluate groundwood pulping tools

2020 ◽  
Vol 35 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Magnus Heldin ◽  
Urban Wiklund
Keyword(s):  
Energy Consumption ◽  
Separation Process ◽  
Energy Requirements ◽  
Effect Of Temperature ◽  
Robust Testing ◽  
Different Temperatures ◽  
Grinding Stones ◽  
Grinding Tool ◽  
Higher Temperature ◽  
The Cost

AbstractGroundwood pulping is a process that employs large machines, making them difficult to use in research. Lab scale grinders exist, but even though they are smaller, the sizes of the grinding stones or segments make them cumbersome to exchange and tailor. This study presents a method and an apparatus for investigating the detailed mechanisms and the energy requirements behind the fibre separation process. A well-defined grinding tool was used at three different temperatures to demonstrate that the equipment can differentiate levels of energy consumption and defibration rates, confirming the well-known fact that a higher temperature facilitates defibration. It is also shown how the equipment can be used to study the influence of grinding parameters, exemplified by the effect of temperature on the way fibres are separated and the character of the produced fibres. A key feature of the equipment is the use and evaluation of small grinding surfaces, more readily designed, produced, evaluated and studied. This reduces both the cost and time necessary for testing and evaluating. At the same time, a technique to produce well defined grinding surfaces was employed, which is necessary for repeatability and robust testing, not achievable with traditional grinding stones.

scholarly journals Effect of Temperature on Diluate Water in Batch Electrodialysis Reversal

Separations ◽  
2021 ◽  
Vol 8 (12) ◽  
pp. 229
Author(s):  
Germán Eduardo Dévora-Isiordia ◽  
Alejandra Ayala-Espinoza ◽  
Luis Alberto Lares-Rangel ◽  
María Isela Encinas-Guzmán ◽  
Reyna Guadalupe Sánchez-Duarte ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Significant Degree ◽  
Operating Conditions ◽  
Limiting Current ◽  
Effect Of Temperature ◽  
Input Concentration ◽  
Limiting Current Density ◽  
Different Temperatures ◽  
Increasing Temperature ◽  
The Cost

A high percentage of the agricultural wells in the state of Sonora are overexploited, thus generating a significant degree of saline intrusion and abandonment by nearby communities. In this paper, the effect of temperature on the final concentration of diluted water was evaluated with variations in voltage and input concentration in a batch electrodialysis reversal (EDR) process in order to find the optimal operating conditions, with an emphasis on reducing the energy consumption and cost of desalinated water. Thirty-six samples were prepared: eighteen samples of 2000 mg/L total dissolved solids (TDS) and eighteen samples of 5000 mg/L TDS; brackish well water of 639 mg/L TDS and synthetic salt were mixed to obtain these concentrations. Three different temperatures (25, 30, and 35 °C) and two different voltages (10 and 20 V) were tested for each sample after evaluating the limiting current density. The best salt removal occurred in the 20 V sets, with 18.34% higher removal for the 2000 mg/L TDS experiments and 25.05% for the 5000 mg/L experiments (average between the 25 to 35 °C tests). The temperature positively affected the EDR, especially in the experiments at 10 V, where increasing by 10 °C increased the efficiency by 10.83% and 24.69% for 2000 and 5000 mg/L TDS, respectively. The energy consumption was lower with increasing temperature (35 °C), as it decreased by 1.405% and 1.613% for the 2000 and 5000 mg/L TDS concentrations, respectively (average between the 10 and 20 V tests), thus decreasing the cost per m3 of water.

scholarly journals Temperature Effect on Permeate Water in Batch Electrodialysis Reversal

2021 ◽  
Author(s):  
Germán Eduardo Dévora-Isiordia ◽  
Alejandra Ayala-Espinoza ◽  
Luis Alberto Lares-Rangel
Keyword(s):  
Energy Consumption ◽  
Temperature Effect ◽  
Operating Conditions ◽  
Optimal Operating ◽  
Different Temperatures ◽  
Agricultural Use ◽  
Reduction Of Energy Consumption ◽  
Increasing Temperature ◽  
The Cost ◽  
High Degree

Currently, a large part of the wells for agricultural use located in the state of Sonora are overexploited, which generates a high degree of saline intrusion and abandonment by nearby communities. In this paper the temperature effect on the final concentration of permeate water was evaluated through voltage and intel concentration variations in a batch electrodialysis reversal process (EDR), in order to identify optimal operating conditions with emphasis on the reduction of energy consumption and cost of desalinated water. Thirty-six samples were prepared: eighteen 2,000 mg/L total dissolved solids (TDS) samples and eighteen 5,000 mg/L TDS samples; brackish well water of 639 mg/L TDS and synthetic salt were mixed to obtain those concentrations. 3 different temperatures (25, 30, 35 °C) and 2 different voltages (10 and 20 V) were tested for each sample. The best salt removal occurred in the 20 V arrays, with 18.34% higher removal for 2,000 mg/L TDS experiments and 25.05% for 5,000 mg/L experiments (average between the 25 to 35 °C tests). Temperature positively affected EDR, especially in the experiments at 10 V voltage, where increasing 10 °C increased its efficiency by 10.83% and 24.69% for 2,000 and 5,000 mg/L TDS, respectively. Energy consumption was lower with increasing temperature (35 °C), as it decreased by 1.405% and 1.613% for 2,000 and 5,000 mg/L TDS concentrations, respectively (average between 10 and 20 V tests), decreasing the cost per m3 of water.

scholarly journals Modelling of Average Pore Size and Porosity of Porous Polycaprolactone/Hydroxyapatite (PCL/HA) Composite Blends

2019 ◽  
Vol 9 (1) ◽  
pp. 5791-5797
Keyword(s):  
Pore Size ◽  
Average Pore Size ◽  
Effect Of Temperature ◽  
Coefficient Of Determination ◽  
Average Pore ◽  
Foaming Process ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Predicted Values ◽  
Experimental Values

The objective of this paper is to develop mathematical relationship between average pore size and porosity of porous polycaprolactone/hydroxyapatite (PCL/HA) composite and investigate the combined effect of temperature and pressure of foaming process and presence of HA. Porous PCL/HA composite was prepared using supercritical carbon dioxide (ScCO2) solid state foaming process. Three different temperatures and pressures of foaming process were varied at 35°C, 40°C, 45°C and 10MPa, 20MPa, 30MPa respectively. Meanwhile weight of HA was varied at 10, 20, 30 and 40 wt%. The result from analysis of variance (ANOVA) using Microsoft Excel found that average pore size is reduced with higher pressure and content of HA presence does not significantly affect the average pore size due to poor distribution of HA. Meanwhile for porosity, higher temperature is more dominant in increasing of porosity compared to the HA content. In addition, both designed models have low values of Average Absolute Relative Deviation (%AARD) and high value of coefficient of determination (R2 ) which reflects a good and satisfying result between the experimental values and model predicted values.

scholarly journals THE EFFECT OF TEMPERATURE ON THE PERFORMANCE OF ACTIVATED CARBON OVER CATALYTIC CRACKING OF CRUDE PALM OIL

2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Nazarudin Nazarudin ◽  
Ulyarti Ulyarti ◽  
Oky Alfernando ◽  
Ira Galih ◽  
Susilawati Susilawati ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Palm Oil ◽  
Active Carbon ◽  
Catalytic Cracking ◽  
Effect Of Temperature ◽  
Crude Palm Oil ◽  
Carbon Catalyst ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Catalyst Increase

This research was carried out to investigate the effect of temperature in carbon production on its performance in the catalystic cracking of CPO to fuel.  The carbon was produced using palm shell at 2 different temperatures (450 and 550oC).  The cracking of CPO was carried out with and without the active carbon catalyst.  The result showed that the use of catalyst increase the conversion of both gas and liquid conversion.  The use of higher temperature in the production of active carbon catalyst increased the performance of the catalyst, in particular, for the liquid conversion. Keywords :Activated carbon, catalyst, catalytic cracking, crude palm oil

Determination of Energy Intensities in the Indian Economy

1979 ◽  
Vol 4 (2) ◽  
pp. 149-160
Author(s):  
S. Subba Rao ◽  
Mukesh Raizada ◽  
S. Chidambara Iyer ◽  
A. Ramanathan
Keyword(s):  
Energy Consumption ◽  
Cost Structure ◽  
Energy Requirements ◽  
Energy Costs ◽  
Indian Economy ◽  
Goods And Services ◽  
The Cost ◽  
And Control ◽  
Energy Intensities

This paper applies Herendeen's methodology for deriving energy costs and energy intensities for the Indian economy. An idea of the part energy plays in the cost structure of various goods and services as well as the intensities of energy requirements in various activities is obtained from this analysis. The methodology will be helpful for energy planners to project and control energy consumption in the economy.

Effect of temperature on the bond-slip between I-shaped steel and concrete

2021 ◽  
pp. 136943322199355
Author(s):  
Yuzhuo Wang ◽  
Bingjie Zhang ◽  
Ziqing Liu ◽  
Ying Gao ◽  
Chuanguo Fu
Keyword(s):  
Bond Strength ◽  
High Temperatures ◽  
Room Temperature ◽  
Effect Of Temperature ◽  
Bond Slip ◽  
Steel Columns ◽  
Different Temperatures ◽  
Higher Temperature ◽  
S Curve ◽  
Test Furnace

This paper presents results from an experimental study on the effect of temperature on bond strength of I-shaped steel and concrete. Eleven concrete encased steel (CES) specimens were tested by home-made fire test furnace to evaluate bond strength at various constant high temperatures (20°C600°C). The test results showed that: (1) the trend of the bond-slip curves at high temperatures were much similar to that at room temperature. Compared with room temperature specimen, the ultimate bond load and the residual bond load of specimens at high temperatures were significantly decreased. The specimens with the higher temperature had the less ultimate bond load and residual bond load. (2) In the descending stage, the P-S curve of the specimens with higher temperatures had more flat slope. The P-S curve of the specimens at the temperatures higher than 250°C had invisible descending stage. The ultimate bond load of the specimen at 600°C left with only about 5% of that at room temperature. (3) The ultimate slippages (i.e. the slippage at the ultimate bond load) of specimens at high temperatures were larger than that at room temperature, and varied from 2 to 5 mm. (4) The calculation formulas of ultimate bond load, ultimate slippage, and residual bond load at different temperatures were presented, the constitutive equations of bond-slip at different temperatures were obtained, which will provide a reference for the fire-resistant design of concrete encased steel columns.

Studies on the Toxicity of insecticide Films. II.—Effect of Temperature on the Toxicity of DDT Films

1949 ◽  
Vol 40 (2) ◽  
pp. 239-265 ◽  
Author(s):  
S. Pradhan
Keyword(s):  
Effect Of Temperature ◽  
Two Factors ◽  
Different Temperatures ◽  
Insecticidal Action ◽  
Higher Temperature ◽  
Effects Of Temperature ◽  
Insect Activity ◽  
Lower Temperature ◽  
Toxicity Relationship ◽  
The Relationship

1. A series of exploratory experiments on the relationship between temperature and toxicity of DDT films to adults of Tribolium castaneum, and larvae of Plutella maculipennis, are described. The main conclusions with T. castaneum are:—(a) When the insects are continuously kept on the film at different temperatures there is a higher kill at higher temperatures.(b) When the insects are exposed to the film for about 24 hours at the same temperature and then kept away from it at different temperatures there is a higher kill at the lower temperature.(c) When the insects are kept on the film at different temperatures for about 24 hours and then kept away from the film for reaction at the same temperature, there is a higher kill in those kept on the film at the higher temperature.(a) and (b) above apply equally to larvae of P. maculipennis but (c) is reversed. The probable cause of this reversal appears to be the observed fact that at higher temperatures these larvae cover the film with much more silk thread and thus avoid contact to a greater extent than at lower temperatures.2. A review of literature, in the light of the conclusions arrived at, indicate that many of the observations made upon the temperature-toxicity relationship can be accounted for by the following generalisations:—(a) Insect resistance to poisons changes with temperature as do its other vital activities, increasing up to a critical degree and afterwards declining.(b) The amount of poison reaching the site of action in unit time also varies with the temperature, generally but not always, increasing with its rise. Insect activity, especially locomotor and respiratory, may play an important part in these effects.(c) The apparent effects of temperature on insecticidal action is the combination of these two factors, namely, resistance and pick-up.

scholarly journals Evaluation of Saline as Potential Alternative to Viral Transport Media for COVID-19 Samples Stored at Different Temperatures

2021 ◽  
Author(s):  
Parul Sinha ◽  
Dinesh Kumar Jain ◽  
Sandeep Gupta ◽  
Monika Gupta ◽  
Megha Gupta ◽  
...  
Keyword(s):  
Normal Saline ◽  
Effect Of Temperature ◽  
Nucleic Acid Detection ◽  
Infected People ◽  
Viral Transport ◽  
Viral Transport Medium ◽  
Different Temperatures ◽  
Oropharyngeal Swab ◽  
Potential Alternative ◽  
The Cost

Introduction: Severe acute respiratory syndrome coronavirus-2 (SARS CoV 2) virus, a causative agent of COVID-19 has led to universal pandemic. During this pandemic there has been an acute shortage of good quality Viral Transport Medium (VTM) because of increase in number of infected people worldwide. It is also difficult to maintain the transport and storing conditions in line with the guidelines in pandemics. Aim: To assess the feasibility of Oropharyngeal Swab (OP)/Nasal swabs in 0.9% normal saline in place of VTM and to analyse the effect of temperature on nucleic acid detection by rRT PCR on saline samples stored at 4ºC, ambient and at higher temperature (37ºC). Materials and Methods: The present study was an observational analytical study which included 94 positive and 5 negative samples. Patients' nasal or OP samples were collected as dry swabs and in VTM. Normal saline was added once the samples were received in the laboratory. PCR was done with saline and VTM samples both on day 1. Samples were aliquotted in 3 sets and one set was kept at 4º-8º C and other two at 25ºC and 37ºC, respectively. All positive samples were further tested on day 3, day 4 and day 6. Results were analysed and compared. Results: Samples in normal saline showed very good sensitivity at all temperatures (4º-8ºC, 25ºC and 37ºC) till day 6. Both the swab samples (in saline and in VTM) showed nearly 100% agreement in rRT-PCR results. Ct value variation was also ≤±2. Conclusion: Looking into the cost and logistics issues especially during pandemics, saline is a good and cheaper alternative to VTM and with its use, testing capacity can be expanded.

Effect of Temperature on Tribological Performances of Ion Nitrocarburized Layer of 42MnCr52 Steel

2013 ◽  
Vol 750-752 ◽  
pp. 389-392
Author(s):  
Chun Hua Hu ◽  
Feng Jun Qi ◽  
Meng Liang Lu ◽  
Guo Ning Wang ◽  
Qian Liu ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Friction Factor ◽  
Wear Scar ◽  
Friction Reduction ◽  
Effect Of Temperature ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Plain Surface ◽  
Nitrocarburized Layer ◽  
Scar Width

The paper studied that effect of temperature on tribological performances of ion nitrocarburized layer of 42MnCr52 steel under CD15W-40 oil lubricating. It is found that the ion nitrocarburized layer has more excellent friction reduction and wear resistance performances than the plain surface under different temperatures, especially under the higher temperature 150°C, the friction factor and wear scar width of ion nitrocarburized layer is 36% and 77% less than that of the plain surface respectively, which indicates that ion nitrocarburized layer can play more excellent friction reduction, wear resistance and scuffing resistance performances under the relative higher temperature.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

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