scholarly journals Pyrolysis of Technogenic-Redeposited Coal-Bearing Rocks of Spoil Heaps

Geosciences ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 122
Author(s):  
Nikolay I. Akulov ◽  
Varvara V. Akulova
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Kuznetsk Coal ◽  
Sulphur Compounds ◽  
Average Speed ◽  
Average Temperature ◽  
Polycyclic Aromatic ◽  
Low Temperature Pyrolysis ◽  
Bottom To Top ◽  
Spoil Heaps

The paper presents the results of a study of epigenetic changes in technogenic-redeposited coal-bearing rocks of Irkutsk and Kuznetsk coal basin spoil heaps (Russia). Hydrocarbon products formed under high-temperature and low-temperature pyrolysis of coal-bearing rocks were studied by using a chromatography-mass spectrometer GCMS-QP2010NC Plus (made by Shimadzu Company). The average temperature of low-temperature natural pyrolysis does not exceed 120 °C, and its average speed is approximately 2 m/year. In this case, three pyrolysis zones gradually built metamorphic rock mass (from bottom to top) are clearly established: heating (focal) activated and enriched. The average temperature of high-temperature pyrolysis reaches 850 °C, and its average speed is approximately 20 m/year. Unlike low-temperature pyrolysis, high-temperature pyrolysis is accompanied by the presence of two major zones (from bottom to top): pyrogenic (focal) and enriched (coke). The chemical composition of the enriched pyrolysis zone was studied in detail. It has been established that hydrocarbon compounds in samples of the pyrolysis zone are presented by six classes: asphaltic-resinous substances; polycyclic aromatic hydrocarbons, heterocyclic compounds, organic sulphur compounds; pyrolytic hydrocarbon and heavy hydrocarbon residue. Quantitative content of hydrocarbon compounds in the analyzed samples varies from 0.35% to 41.88%.

scholarly journals High- and low-temperature pyrolysis profiles describe volatile organic compound emissions from western US wildfire fuels

2018 ◽  
Author(s):  
Kanako Sekimoto ◽  
Abigail R. Koss ◽  
Jessica B. Gilman ◽  
Vanessa Selimovic ◽  
Matthew M. Coggon ◽  
...  
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Biomass Burning ◽  
Ponderosa Pine ◽  
Fine Particles ◽  
Voc Emissions ◽  
Western Us ◽  
Volatile Organic ◽  
Low Temperature Pyrolysis ◽  
Pyrolysis Processes

Abstract. Biomass burning is a large source of volatile organic compounds (VOCs) and many other trace species to the atmosphere, which can act as precursors to the formation of secondary pollutants such as ozone and fine particles. Measurements collected with a proton-transfer-reaction time-of-flight mass spectrometer during the FIREX 2016 laboratory intensive were analyzed with Positive Matrix Factorization (PMF), in order to understand the instantaneous variability in VOC emissions from biomass burning, and to simplify the description of these types of emissions. Despite the complexity and variability of emissions, we found that a solution including just two emission profiles, which are mass spectral representations of the relative abundances of emitted VOCs, explained on average 85 % of the VOC emissions across various fuels representative of the western US (including various coniferous and chaparral fuels). In addition, the profiles were remarkably similar across almost all of the fuel types tested. For example, the correlation coefficient r of each profile between Ponderosa pine (coniferous tree) and Manzanita (chaparral) is higher than 0.9. We identified the two VOC profiles as resulting from high-temperature and low-temperature pyrolysis processes known to form VOCs in biomass burning. High-temperature and low-temperature pyrolysis processes do not correspond exactly to the commonly used flaming and smoldering categories as described by modified combustion efficiency (MCE). The average atmospheric properties (e.g. OH reactivity, volatility, etc.) of the high- and low-temperature profiles are significantly different. We also found that the two VOC profiles can describe previously reported VOC data for laboratory and field burns. This indicates that the high- and low-temperature pyrolysis profiles could be widely useful to model VOC emissions from many types of biomass burning in the western US, with a few exceptions such as burns of duff and rotten wood.

scholarly journals Evaluation of the lipid fraction of pyrochars organic matter in the aspect of negative effects on soil

2020 ◽  
Vol 17 ◽  
pp. 00156
Author(s):  
Rodion Okunev ◽  
Elena Smirnova ◽  
Kamil Giniyatullin ◽  
Irina Guseva
Keyword(s):  
Organic Matter ◽  
Low Temperature ◽  
Pyrolysis Temperature ◽  
Lipid Fraction ◽  
Total Content ◽  
Negative Effects ◽  
Polycyclic Aromatic ◽  
Negative Effect ◽  
Pahs Concentration ◽  
Low Temperature Pyrolysis

The evaluation of the possible negative effect of pyrochars on soils based on the analysis of the content of lipid fraction and polycyclic aromatic hydrocarbons (PAHs) of organic matter was evaluated. Eight species of pyrochar were obtained from the crop and wood residues (linden, willow, corn, millet) by two pyrolysis regimes: low-temperature pyrolysis (<400°C) and high-temperature pyrolysis (400–600°C). The largest amount of lipid fraction (from 0.54 to 2.78%) and PAHs were found in pyrochars obtained at a low pyrolysis temperature. The total content of PAHs in the studied samples ranged from 8.49 to 603.21 μg/kg. According to the PAHs content, pyrochar was the most adverse for application to the soil, obtained from the residues of millet of low-temperature pyrolysis, however, at a high pyrolysis temperature, the safest product with the lowest PAHs concentration and a significant amount of lipid fraction was formed. Using an incubation experiment by measuring substrate-induced respiration in soil-pyrochar mixtures, it was shown that the application of this meliorant can also increase the emission of carbon dioxide from soils in a short time. The results of the experiments showed that it is necessary to precisely control the conditions of pyrolysis and carefully select the material for pyrochar in order to obtain the products with most favourable amounts of lipid fraction and PAHs content.

Research Progress of Oil Making from Sewage Sludge

2016 ◽  
Vol 851 ◽  
pp. 232-236
Author(s):  
Jiang Long Lu ◽  
Guo Ri Dong ◽  
Fang Chen ◽  
Ji Bin Wang
Keyword(s):  
High Temperature ◽  
Sewage Sludge ◽  
Low Temperature ◽  
Hot Spots ◽  
Energy Utilization ◽  
Research Progress ◽  
Treatment And Disposal ◽  
Low Temperature Pyrolysis

the treatment and disposal of sewage sludge is one of the hot spots in recent years, and the value of its energy utilization has gradually received attention by researchers. In this paper, the concept, yield, harm as well as the conventional disposal methods of sewage sludge are described, three kinds of main technologies of oil making from sewage sludge are introduced, including high temperature pyrolysis, low-temperature pyrolysis and direct thermo chemical liquefaction, and the research progress of these three technologies is reviewed.

Effect of the Mixing-Melt and Superheating on the Primary Si Phase of Hypereutectic Al-20%Si Alloy

2010 ◽  
Vol 146-147 ◽  
pp. 79-88
Author(s):  
Lian Deng Wang ◽  
Ding Yi Zhu ◽  
Zhe Liang Wei ◽  
Yong Lu Chen ◽  
Li Guang Huang ◽  
...  
Keyword(s):  
Grain Size ◽  
High Temperature ◽  
Low Temperature ◽  
Melt Mixing ◽  
Local Melting ◽  
Average Temperature ◽  
Present Alloy ◽  
Primary Si

The Al-20%Si alloy was prepared by mixing the high temperature melt of hypereutectic Al-30%Si alloy with the pre-crystallized low temperature hypoeutectic Al-10%Si alloy melt and then superheating the mixture, i.e., melts mixing and superheating (for short: MMS), combining with chemical metamorphism. The effect of pre-crystallized characteristic of the mixed melt on microstructure of Al-20%Si alloy was then investigated, The primary Si granules of the sample, poured by melt mixing with different composition and temperature, were well distributed with a grain size of less than 36μm. And after superheating, the primary Si phase of the mixed melt could be further refined and distributed more uniformly, which if adding the modificator into the mixed melt, the size of primary Si were been deceased and refined by less than 20μm. The analysis result shows that the decrease in the temperature of the mixed melt, from the average temperature of 740 °C for the mixture of Al-30%Si (900°C) and Al-10%Si (580°C) to 670°C for present alloy, leads to the increase in the degree of undercooling, and consequently to the refinement of primary Si. During the superheating, the growth, local melting, as well as the proliferation of primary Si occurred because of the unhomogeneous micro-distribution of the temperature and composition within the mixing melt, resulting in the further decrease in the grain size of primary Si. And adding the modificator could promote the effect of modification of primary Si of MMS process on the hypereutectic Al-Si alloy.

Evaluation of the Environmental Bias on Accelerometer-Measured Total Daily Activity Counts and Owner Survey Responses in Dogs with Osteoarthritis

2017 ◽  
Vol 30 (06) ◽  
pp. 385-390 ◽  
Author(s):  
Erin Katz ◽  
Ruth Scott ◽  
Christopher Thomson ◽  
Eileen Mesa ◽  
Richard Evans ◽  
...  
Keyword(s):  
High Temperature ◽  
Relative Humidity ◽  
Low Temperature ◽  
Daily Activity ◽  
Environmental Variables ◽  
Brief Pain Inventory ◽  
Barometric Pressure ◽  
Pain Severity ◽  
Total Precipitation ◽  
Average Temperature

Abstract Objective To determine if environmental variables affect the average daily activity counts (AC) of dogs with osteoarthritis (OA) and/or owners’ perception of their dog’s clinical signs or quality of life. Methods The AC and Canine Brief Pain Inventory (CBPI) owner questionnaires of 62 dogs with OA were compared with daily environmental variables including the following: average temperature (°C), high temperature (°C), low temperature (°C), relative humidity (%), total precipitation (mm), average barometric pressure (hPa) and total daylight hours. Results Daily AC significantly correlated with average temperature and total daylight hours, but average temperature and total daylight hours accounted for less than 1% of variation in AC. No other significant relationships were found between daily AC and daily high temperature, low temperature, relative humidity, total precipitation or average barometric pressure. No statistical relationship was found between daily AC and the CBPI, nor between environmental variables and the CBPI. Canine Brief Pain Inventory scores for pain severity and pain interference decreased significantly over the test period. Clinical Significance The relationship between daily AC and average temperature and total daylight hours was significant, but unlikely to be clinically significant. Thus, environmental variables do not appear to have a clinically relevant bias on AC or owner CBPI questionnaires. The decrease over time in CBPI pain severity and pain interference values suggests owners completing the CBPI in this study were influenced by a caregiver placebo effect.

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

INFLUENCE OF FORCED CONVECTION IN LIQUID INSIDE THE TIN ON DURATION OF STERILIZATION IN THE COURSE OF FISH PROCESSING

2017 ◽  
pp. 137-144
Author(s):  
Gennadiy Valentinovich Alexeev ◽  
Elena Igorevna Verboloz
Keyword(s):  
High Temperature ◽  
Liquid Phase ◽  
Forced Convection ◽  
Thermal Process ◽  
Processing Time ◽  
Fish Processing ◽  
Study Results ◽  
Equipment Modernization ◽  
Bottom To Top

The article focuses on the process of intensive mixing of liquid phase in the tin during high-temperature sterilization, i.e. sterilization when temperature of the heat carrier reaches 150-160°C. It has been stated that for intensification of the thermal process during sterilization of tinned fish with liquid filling it is preferable to turn a tin from bottom to top. This operation helps to increase the driving power of the process and to shorten warming time. Besides, high-temperature sterilization carried out according to experimental modes, where the number of tin turnovers is calculated, greatly shortens processing time and improves quality of the product. In this case there is no superheating, all tins are evenly heated. The study results will contribute to equipment modernization and to preserving valuable food qualities.

Superconducting Wind Generators with Capacities of 10 MW and Larger

2020 ◽  
Vol 10 (10) ◽  
pp. 59-67
Author(s):  
Victor N. ANTIPOV ◽  
◽  
Andrey D. GROZOV ◽  
Anna V. IVANOVA ◽  
◽  
...  
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Wind Power ◽  
State Of The Art ◽  
Superconducting Materials ◽  
Commercial Application ◽  
Synchronous Generators ◽  
High Temperature Superconducting ◽  
Wind Generators ◽  
Main Factor

The overall dimensions and mass of wind power units with capacities larger than 10 MW can be improved and their cost can be decreased by developing and constructing superconducting synchronous generators. The article analyzes foreign conceptual designs of superconducting synchronous generators based on different principles: with the use of high- and low-temperature superconductivity, fully superconducting or only with a superconducting excitation system, and with the use of different materials (MgB2, Bi2223, YBCO). A high cost of superconducting materials is the main factor impeding commercial application of superconducting generators. In view of the state of the art in the technology for manufacturing superconductors and their cost, a conclusion is drawn, according to which a synchronous gearless superconducting wind generator with a capacity of 10 MW with the field winding made of a high-temperature superconducting material (MgB2, Bi-2223 or YBCO) with the «ferromagnetic stator — ferromagnetic rotor» topology, with the stator diameter equal to 7—9 m, and with the number of poles equal to 32—40 has prospects for its practical use in the nearest future.

Chemical yields from low-temperature pyrolysis of CCA-treated wood

2009 ◽  
Author(s):  
Qirong Fu ◽  
Dimitris Argyropolous ◽  
Lucian Lucia ◽  
David Tilotta ◽  
Stan Lebow
Keyword(s):  
Low Temperature ◽  
Treated Wood ◽  
Low Temperature Pyrolysis
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