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1
Cheng, Xue Zhen, Ji Ming Li, Qi Li, Mao Yong Cao, and Laxmisha Rai. "A Novel Coal Water Content Measurement Method on Conveyor Belt." Advanced Materials Research 503-504 (April 2012): 1292–97. http://dx.doi.org/10.4028/www.scientific.net/amr.503-504.1292.
Повний текст джерелаАнотація:
The coal dust storms create great harm to the environment and human health. The main source of coal dust is the low coal moisture on various types of coal conveying belt. The intensity of coal dust is heavy, especially in the coal-fired power plant, coal transportation coal conveyor belt and in areas, where various reprint point was heavy. In this paper, a measurement method on moisture content of coal conveying belt was proposed. The local group based on the probability can eliminate the factors affecting measuring accuracy such as the big piece of coal, the thickness of coal seam, and coal rock. The rationality behind the measurement was verified by simulation experiments. The proposed method gives an effective method to measure the moisture content of coal on the conveyer belt and provides technical support to prevent the spontaneous combustion and explosion of coal when the moisture content of coal is too low.
2
Li, Ming, Jun Tian, Yuliang Wang, Haiyang Zhang, Dongping Yang, and Meng Lei. "Intelligent Measurement of Coal Moisture Based on Microwave Spectrum via Distance-Weighted kNN." Applied Sciences 12, no. 12 (June 18, 2022): 6199. http://dx.doi.org/10.3390/app12126199.
Повний текст джерелаАнотація:
Realizing the rapid measurement of coal moisture content (MC) is of great significance. However, existing measurement methods are time-consuming and damage the original properties of the samples. To address these concerns, a coal MC intelligent measurement system is designed in this study that integrates microwave spectrum analysis and the distance-weighted k-nearest neighbor (DW-kNN) algorithm to realize rapid and non-destructive measurement of coal MC. Specifically, the measurement system is built using portable microwave analysis equipment, which can efficiently collect the microwave signals of coal. To improve the cleanliness of modeling data, an iterative clipping method based on Mahalanobis distance (MD-ICM) is used to detect and eliminate outliers. Based on multiple microwave frequency bands, various machine learning methods are evaluated, and it is found that coal MC measurement using broad frequency signals of 8.05–12.01 GHz yields the best results. Experiments are also carried out on coals from different regions to examine the regional robustness of the proposed method. The results of on-site testing with 27 additional samples show that the method based on the combination of microwave spectrum analysis and DW-kNN has a potential application prospect in the rapid measurement of coal MC.
3
Ren, Si Yuan, Ying Bo Chen, Guang Chen Yu, and Can Song. "Experimental Study of Coal Moisture Content Measurement System Based on Standing-Wave Ratio." Advanced Materials Research 1008-1009 (August 2014): 514–19. http://dx.doi.org/10.4028/www.scientific.net/amr.1008-1009.514.
Повний текст джерелаАнотація:
In this paper, a measurement system is designed to deal with the problem of measurement of the coal moisture content. Based on the measurement principle including standing-wave ratio and permittivity, develop the whole measurement system from the hardware and software aspects. The measurement system of coal moisture content based on standing-wave ratio has the advantages of less measuring time, higher accuracy and larger measurement range according to the results. And it can apply in the coal moisture content measurement in many industry fields.
4
Haryono, Didied, Desiani, Mahfudz Al Huda, Warsito P. Taruno, Marlin R. Baidillah, and Irwin Maulana. "Characterization of Various Types Coal Using Capacitance Measurement Technique." Advanced Materials Research 1112 (July 2015): 506–9. http://dx.doi.org/10.4028/www.scientific.net/amr.1112.506.
Повний текст джерелаАнотація:
Each type of coal has different composition and properties, which determine the coal rank. One of the new methods for determining the quality of coal is by measuring its capacitance. It is formerly known that the difference in the moisture content of coal can be determined from the difference in its dielectric properties. The purpose of this paper is to characterize the various types of coal based on capacitance measurement. The samples used are Lignite, Sub-bituminous, Bituminous, and Anthracite. The proximate analysis testing was done to determine the content of moisture, volatile matter, ash, and fixed carbon. Capacitance value is measured using 2-channel data acquisition system (DAS) and parallel plate capacitive sensor at frequency 2.5 MHz. The results shows that the capacitance values of each type of coal are different. The capacitance value is affected by moisture content of coal since the moisture content and capacitance value have a linear correlation. And also, the signal characterization using frequency from 1 kHz to 5 MHz was performed to verify whether the frequency used in the DAS is able to characterize coal types.
5
Jones, T. F., J. Haynes, and T. Jones. "Presentation of Coal for Microwave Moisture Measurement." Measurement and Control 25, no. 3 (April 1992): 78–81. http://dx.doi.org/10.1177/002029409202500303.
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6
Maulana, Iriwn, Didied Haryono, Warsito P. Taruno, Mahfudz Al Huda, Marlin Baidillah, and Rommy I. Sulaiman. "Investigation of Moisture in Coal Using Electrical Capacitance Volume Tomography." Advanced Materials Research 896 (February 2014): 701–5. http://dx.doi.org/10.4028/www.scientific.net/amr.896.701.
Повний текст джерелаАнотація:
A preliminary study about the development of Electrical Capacitance Volume Tomography (ECVT) for determining moisture, calorie and the flow of coal mass real-time on the conveyor has been done. This study aims to examine the capability and sensitivity of ECVT as a capacitance measurement system to investigate the correlation between moisture in coal and its dielectric property. The ECVT system comprises of a 2-channel rectangular sensor, data acquisition system and a computer system to control the measurement, process data and display the data of normalized capacitance of coal as the result. The linear correlation between moisture in coal and data of coal relative capacitance is obtained and presented in this paper. The results have shown that ECVT has good capability and sensitivity as a system to monitor the dielectric property and behavior of coal which are affected by the moisture content
7
Liu, Nan, Chuanming Li, Ruimin Feng, Xin Xia, and Xiang Gao. "Experimental Study of the Influence of Moisture Content on the Mechanical Properties and Energy Storage Characteristics of Coal." Geofluids 2021 (July 24, 2021): 1–12. http://dx.doi.org/10.1155/2021/6838092.
Повний текст джерелаАнотація:
Rock burst occurs frequently as coal mining depth goes deeper, which seriously impacts the safety production of underground coal mines. Coal seam water injection is a technique commonly used to prevent and control such accidents. Moisture content is a critical factor tightly related to rock burst; however, an in-depth insight is required to discover their relationship. In this study, the influence of moisture content on the mechanical properties of coal and rock burst tendency is explored via multiple measurement techniques: uniaxial compression test, cyclic loading/unloading test, and acoustic emission (AE) test. These tests were performed on coal samples using the MTS-816 rock mechanics servo testing machine and AE system. The testing results showed that with the increase in moisture content, the peak strength and elastic modulus of each coal sample are reduced while the peak strain increases. The duration of the elastic deformation phase in the complete stress-strain curves of coal samples is shortened. As the moisture content increases, the area of hysteretic loop and elastic energy index W ET of each coal sample are reduced, and the impact energy index K E is negatively correlated with the moisture content, whereas dynamic failure time is positively correlated with the moisture content, but this variation trend is gradually mitigated with the continuous increase of moisture content. The failure of the coal sample is accompanied by the sharp increase in the AE ring-down count, whose peak value lags behind the peak stress, and the ring-down count is still generated after the coal sample reached the peak stress. With the increase in moisture content, the failure mode of the coal sample is gradually inclined to tensile failure. The above test results manifested that the strength of the coal sample is weakened to some extent after holding moisture, the accumulative elastic energy is reduced in case of coal failure, and thus, coal and rock burst tendency can be alleviated. The study results can provide a theoretical reference for studying the fracture instability of moisture-bearing coal and prevention of coal and rock burst by the water injection technique.
8
Wang, Yingjin, Dameng Liu, Yidong Cai, and Xiawei Li. "Variation of Petrophysical Properties and Adsorption Capacity in Different Rank Coals: An Experimental Study of Coals from the Junggar, Ordos and Qinshui Basins in China." Energies 12, no. 6 (March 13, 2019): 986. http://dx.doi.org/10.3390/en12060986.
Повний текст джерелаАнотація:
The petrophysical properties of coal will vary during coalification, and thus affect the methane adsorption capacity. In order to clarify the variation rule and its controlling effect on methane adsorption, various petrophysical tests including proximate analysis, moisture measurement, methane isothermal adsorption, mercury injection, etc. were carried out on 60 coal samples collected from the Junggar, Ordos and Qinshui basins in China. In this work, the boundary values of maximum vitrinite reflectance (Ro,m) for dividing low rank, medium rank and high rank coals are set as 0.65% and 2.0%. The results show that vitrinite is the most abundant maceral, but the maceral contents are controlled by sedimentation without any relation to coal rank. Both the moisture content and porosity results show higher values in the low ranks and stabilized with Ro,m beyond 1%. Ro,m and VL (daf) show quadratic correlation with the peak located in Ro,m = 4.5–5%, with the coefficient (R2) reaching 0.86. PL decrease rapidly before Ro,m = 1.5%, then increase slowly. DAP is established to quantify the inhibitory effect of moisture on methane adsorption capacity, which shows periodic relationship with Ro,m: the inhibitory effect in lignite is the weakest and increases during coalification, then remains constant at Ro,m = 1.8% to 3.5%, and finally increases again. In the high metamorphic stage, clay minerals are more moisture-absorbent than coal, and the inherent moisture negatively correlates with the ratio of vitrinite to inertinite (V/I). During coalification, micro gas pores gradually become dominant, fractures tends to be well oriented and extended, and clay filling becomes more common. These findings can help us better understand the variation of petrophysical properties and adsorption capacity in different rank coals.
9
Li, Bo, Chaohui Zong, Laisheng Huang, Yongjie Ren, and Xiaoquan Lv. "Study on the Influence of Liquid Nitrogen Cold Soaking on the Temperature Variations and Seepage Characteristics of Coal Samples with Different Moisture Contents." Geofluids 2021 (October 19, 2021): 1–10. http://dx.doi.org/10.1155/2021/8924016.
Повний текст джерелаАнотація:
Due to its advantages such as environmental friendliness and remarkable permeability enhancement effect, the technology of liquid nitrogen cold soaking (LNCS) cracking coal has become a hot spot in the research on coal seam permeability enhancement in recent years. The frost heave force generated by water-ice phase transformation and the temperature stress are the main mechanisms of LNCS cracking water-containing coal. This paper focuses on the effect of LNCS on the temperature variations and seepage characteristics of coal. To further this purpose, the temperature measurement test and the permeability test were conducted on coal samples with different moisture contents under LNCS, respectively. In addition, by comparing the computer tomography test results of coal samples before and after LNCS, the internal pore structure changes of coal samples were further analyzed from a three-dimensional perspective. The test results show that the coal sample with a higher moisture content consumes a shorter time to reach internal temperature equilibrium and experiences faster temperature changes. LNCS can enhance coal permeability, and the growth rate of permeability increases exponentially with the increase of moisture content. After the LNCS treatment, the dried coal sample is mainly sprouting new pores on the basis of primary pores; in contrast, for water-containing coal samples, new pores are sprouted while primary pores will penetrate each other spatially to form a fracture network. In the process of LNCS, moisture has a significant effect on the seepage characteristics of coal, so appropriately increasing the moisture content of the coal seam conduces to achieving a better permeability enhancement effect.
10
Cutmore, N. G., D. G. Miljak, T. G. Rowlands, D. Crnokrak, and A. J. McEwan. "On-Conveyor Measurement of Moisture in Coal Using Low Frequency Microwaves." Coal Preparation 22, no. 3 (May 2002): 151–63. http://dx.doi.org/10.1080/07349340213849.
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11
Zhou, Yiyou, Quanjun Zheng, Xiaoying Hu, Hui Liang, and Changqing Dong. "Research on coal moisture analysis model based on near infrared spectroscopy." IOP Conference Series: Earth and Environmental Science 983, no. 1 (February 1, 2022): 012092. http://dx.doi.org/10.1088/1755-1315/983/1/012092.
Повний текст джерелаАнотація:
Abstract In order to make full use of the advantages of rapid and non-destructive measurement of coal moisture by near-infrared spectroscopy, the 29 original coal samples in the experiment were artificially humidified, and the moisture content of each coal sample was controlled within a different interval of 0-40%; diffuse reflectance near-infrared spectra were collected on the coal samples. The sample was selected according to the random method, Kennard-Stone (KS) method, and Rank-KS method for the selection of calibration set and prediction set. The prediction models of coal moisture content were established by multiple linear regression (MLR) and partial least squares algorithm (PLS) combined with different spectral pretreatment methods, furthermore, water modeling based on BP neural network was established according to optimal sample classification. The results show that when Rank-KS algorithm was used to select correction set and prediction set, the prediction ability of water content prediction model can be significantly improved by using either MLR or PLS, and the root mean square error of prediction (RMSEP) can be minimized; the moisture prediction model of the BP neural network algorithm based on the full-spectrum feature information is the best, the RMSEP value is the smallest among all models, and the model has the best prediction ability.
12
Mandavgade, N. K., S. B. Jaju, and R. R. Lakhe. "Determination of Uncertainty in Gross Calorific Value of Coal Using Bomb Calorimeter." International Journal of Measurement Technologies and Instrumentation Engineering 1, no. 4 (October 2011): 45–52. http://dx.doi.org/10.4018/ijmtie.2011100104.
Повний текст джерелаАнотація:
A bomb calorimeter is an apparatus used for measuring the performance of coal in term of heat of combustion. Recent awareness has been created regarding uncertainty of measurement, due to mainly two reasons. Laboratory accreditation, which has steadily been on the rise, which requires a estimation of uncertainty of measurement particularly in the field of calibration. Second, increased maturity level of the quality system certification as the manufacturing companies looking at the reliability of measurement through correct calibration of inspection, measuring and test equipment. The quality of coal is decided by the various parameters such as ash content, air dried moisture, volatile matter, gross calorific value and sulphur content etc. The grade of coal is decided by the quality of coal which decides the performance of generation of electricity. The uncertainty of measurement in bomb calorimeter gets affected by various parameters. This paper describes the methodology, uncertainty calculations and effects of individual factors on it.
13
Zhang, Jiyuan, Qihong Feng, Xianmin Zhang, Qiujia Hu, Jiaosheng Yang, and Ning Wang. "A Novel Data-Driven Method to Estimate Methane Adsorption Isotherm on Coals Using the Gradient Boosting Decision Tree: A Case Study in the Qinshui Basin, China." Energies 13, no. 20 (October 15, 2020): 5369. http://dx.doi.org/10.3390/en13205369.
Повний текст джерелаАнотація:
The accurate determination of methane adsorption isotherms in coals is crucial for both the evaluation of underground coalbed methane (CBM) reserves and design of development strategies for enhancing CBM recovery. However, the experimental measurement of high-pressure methane adsorption isotherms is extremely tedious and time-consuming. This paper proposed the use of an ensemble machine learning (ML) method, namely the gradient boosting decision tree (GBDT), in order to accurately estimate methane adsorption isotherms based on coal properties in the Qinshui basin, China. The GBDT method was trained to correlate the adsorption amount with coal properties (ash, fixed carbon, moisture, vitrinite, and vitrinite reflectance) and experimental conditions (pressure, equilibrium moisture, and temperature). The results show that the estimated adsorption amounts agree well with the experimental ones, which prove the accuracy and robustness of the GBDT method. A comparison of the GBDT with two commonly used ML methods, namely the artificial neural network (ANN) and support vector machine (SVM), confirms the superiority of GBDT in terms of generalization capability and robustness. Furthermore, relative importance scanning and univariate analysis based on the constructed GBDT model were conducted, which showed that the fixed carbon and ash contents are primary factors that significantly affect the adsorption isotherms for the coal samples in this study.
14
Yu, Anghong, Haizeng Liu, Chuanzhen Wang, Jintao Lv, Feng Wang, Siyang He, and Lei Wang. "Online Ash Content Monitor by Automatic Composition Identification and Dynamic Parameter Adjustment Method in Multicoal Preparation." Processes 10, no. 8 (July 22, 2022): 1432. http://dx.doi.org/10.3390/pr10081432.
Повний текст джерелаАнотація:
The online measurement of coal ash has overcome the shortcomings of chemical tests. However, there could be large fluctuations and errors in the results of online ash monitors because of the transient change in coal quality resulting from different geological conditions in the mining process. In this study, to resolve the problems of the dual-energy γ-ray online ash monitor in the Linhuan Coal Preparation Plant, we investigated the internal factors, such as the composition of multimineral and multicoal, and external factors, such as the moisture and impurities, which affect the measurement results of the coal ash monitor. Furthermore, we developed a mathematical model to determine the effect of relevant factors on the coefficient of the online ash monitor, which revealed the relationship between coal composition and the parameters of the ash monitor, ensuring the stable and accurate measurement of ash in clean coal. The method of determining parameters used in the case of coal blending has been applied in the Linhuan Coal Preparation Plant. By comparing with tested ash content, the average absolute error and relative error for daily ash content measured in April are 0.21 and 2.18%, respectively. Meanwhile, it shows certain accuracy and reproducibility while opposed to the daily average absolute error of 0.22 and relative error of 2.39% in May.
15
Chen, Gang, Wei Su, and Tian Shen Chen. "Analysis into Abnormal Factors Affecting the Ash Discharge Amount of Thermal Power Plant." Advanced Materials Research 664 (February 2013): 1012–17. http://dx.doi.org/10.4028/www.scientific.net/amr.664.1012.
Повний текст джерелаАнотація:
An ash yield experiment and a coal ash component analysis with the same coal sample at different temperatures showed that when a coal sample burned in a boiler furnace whose temperature was higher than 815 ° C, part of the salts (eg, sulfate) and oxides (eg, SO3) would continue to be decomposed, resulting in the actual ash yield of the coal sample decreasing compared with the theoretical ash discharge rate. At the same time, the analysts pointed out that the moisture loss and its representative defects of the as-fired coal sampling machine system, the dust removal efficiency fluctuation of the electrostatic precipitator, and the measurement deviation of the as-fired coal quantity also caused the actual ash discharge rate to be on is low side.
16
Zabolotnyi, O. V., V. A. Zabolotnyi, and M. D. Koshevoi. "Conditionality examination of the new testing algorithms for coal-water slurries moisture measurement." Scientific Bulletin of National Mining University 1 (2018): 51–59. http://dx.doi.org/10.29202/nvngu/2018-1/21.
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Liu, H., H. Tan, H. Hu, X. Xiong, Z. Luo, and Y. Niu. "An Experimental Study on the Measurement of Moisture Content in Coal with Microwaves." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 36, no. 24 (December 3, 2014): 2707–14. http://dx.doi.org/10.1080/15567036.2011.574197.
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Nikku, Markku, Mingxiu Zhan, Kari Myöhänen, Jouni Ritvanen, and Xiaodong Li. "Three-Dimensional Modeling of a Chinese Circulating Fluidized Bed Incinerator Firing Municipal Solid Waste." Journal of Solid Waste Technology and Management 47, no. 2 (May 1, 2021): 393–405. http://dx.doi.org/10.5276/jswtm/2021.393.
Повний текст джерелаАнотація:
Currently waste incineration is a widely used method of waste management in China. Effective incineration requires understanding and tools to analyze the incineration process leading to good incinerator performance and efficiency as well as lower emissions. In this work, a Chinese circulating fluidized bed (CFB) incinerator firing municipal solid waste (MSW) and coal is modeled with a three-dimensional CFB furnace model to evaluate the incineration process. First, the modeling results are verified with measurement data from the incinerator. Then, the furnace model is applied in the simulation of a case with more dry MSW without coal. The objective of the research is to provide insight and increase understanding of the MSW incineration process. The simulation case of MSW with the lower moisture content highlights the possible reductions of fossil carbon emissions associated with the utilization of coal. To achieve this, a moderate reduction in the moisture content of MSW is required. A comparison between the MSW and coal versus only the MSW shows minor differences in the performance of the incinerator. Utilization of modeling in incinerator studies can aid in development of more efficient CFB incinerators, improving the waste management and reducing the utilization of fossil coal.
19
Wang, Shijia, Shibo Wang, and Wanli Liu. "Longwall Retreat and Creep Measurement Based on UWB Radar Imaging Method." Mathematical Problems in Engineering 2020 (May 11, 2020): 1–13. http://dx.doi.org/10.1155/2020/4056246.
Повний текст джерелаАнотація:
The measurement of longwall retreat and creep displacements is of great significance for the safety production of a coal mine. In order to reliably and accurately obtain the longwall retreat and creep displacements, this paper proposes an ultrawideband (UWB) radar imaging method. The bolt plates fixed in the roadway coal wall are imaged as the target points. First, a signal model is built, and a modified nonlinear chirp scaling (NLCS) imaging algorithm is designed to obtain the high-resolution image. Then, the retreat and creep displacements are estimated based on the imaging results. Finally, simulation and experiment are performed. The simulation results show that the radar imaging method is theoretically feasible to measure the retreat and creep displacements. The measurement errors in the experiment are 0.058 m and 0.040 m, respectively. In the experiment, the radar velocity fluctuation and signal attenuation cause the target azimuth and range errors in the imaging results, which makes the measurement errors in the experiment larger than that in the simulation. This method requires no additional roadway information except for the bolt plates fixed in the coal wall. In addition, the signal propagation of UWB radar is rarely affected by the dust and moisture in the harsh environment.
20
Simatupang, David P., and Deddy Amarullah. "COAL BED METHANE POTENCYOF TANJUNG FORMATION IN TANAH BUMBU SOUTH KALIMANTAN." Buletin Sumber Daya Geologi 5, no. 2 (August 31, 2010): 50–57. http://dx.doi.org/10.47599/bsdg.v5i2.256.
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Coal deposits distributes widely in Indonesia, mainly in Sumatera and Kalimantan. These deposits become an indication for a huge quantity of coal-bed methane (CBM) potency. As an environmentally friendly source of energy, CBM could be one of Indonesia's future energy sources. Centre for Geological Resources (CGR) started the exploration for this energy since 2005, while the study was conducted in 2008 at Tanjung Formation in Tanah Bumbu Area, South Kalimantan.CSAT-1 well was drilled to provide CBM resources and deep coal mine potency data for Tanjung Formation (Eocene) in Asem-asem Basin. This well went through 10 coal seams with three main seam, which is E seam at 212.34-213.30 m depth, I seam at 261.93-264.20 m, and J seam at 270.20-275.35 m depth. Calorific value from this three main seam categorized as high rank coal, vary from 6197-6745 cal/gram (adb), with total moisture between 4.51-7.11 %, adb.Total coal resources used for CBM resources quantification is 112,733,226 tons (between 300 to 1000 meters depth). Based on desorption test and gas chromatograph measurement from samples at various depth from three main seams, those coal gives methane resources estimation about 430 MSCF, with methane content vary between 1.2 - 6.6 cu-ft/ton of coal.
21
Kalandarov, P. I., and B. P. Iskandarov. "Measurement of the moisture content of brown coal from the Angrensk deposit and problems of metrological assurance." Measurement Techniques 55, no. 7 (October 2012): 845–48. http://dx.doi.org/10.1007/s11018-012-0049-1.
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Zheng, Sijian, Yanbin Yao, Shasha Zhang, Yong Liu, and Jinhui Yang. "Insights into Multifractal Characterization of Coals by Mercury Intrusion Porosimetry." Energies 12, no. 24 (December 12, 2019): 4743. http://dx.doi.org/10.3390/en12244743.
Повний текст джерелаАнотація:
Mercury intrusion porosimetry (MIP) as a practical and effective measurement has been widely used in characterizing the pore size distribution (PSD) for unconventional reservoirs (e.g., coals and shales). However, in the process of MIP experiments, the high mercury intrusion pressure may cause matrix compressibility and result in inaccurate estimations of PSD. To get a deeper understanding of the variability and heterogeneity characteristics of the actual PSD in coals, this study firstly corrected the high mercury intrusion pressure data in combination with low-temperature N2 adsorption (LTNA) data. The results show that the matrix compressibility was obvious under the pressure over 24.75 MPa, and the calculated matrix compressibility coefficients of bituminous and anthracite coals range from 0.82 to 2.47 × 10−10 m2/N. Then, multifractal analysis was introduced to evaluate the heterogeneity characteristics of coals based on the corrected MIP data. The multifractal dimension Dmin is positively correlated with vitrinite content, but negatively correlated with inertinite content and mercury intrusion saturation. The multifractal dimension Dmax shows negative relationships with moisture and ash content, and it also emerges as a “U-shaped” trend with efficiency of mercury withdrawal. It is concluded that multifractal analysis can be served as a practical method not only for evaluating the heterogeneity of coal PSDs, but also for other unconventional reservoirs (e.g., shale and tight sandstone).
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Archary, Hamresin, Walter Schmitz, and Louis Jestin. "Mass flow and particle size monitoring of pulverised fuel vertical spindle mills." Chemical and Process Engineering 37, no. 2 (June 1, 2016): 175–97. http://dx.doi.org/10.1515/cpe-2016-0016.
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Abstract The first step towards condition based maintenance of the milling plant is the implementation of online condition monitoring of the mill. The following paper presents and analyses methods of monitoring the key performance factors of a vertical spindle mill that is suited for implementation on older power stations, i.e. the quantity (mass flow rate) and quality (particle fineness) of the pulverised fuel produced by the mill. It is shown herein that the mill throughput can be monitored on-line using a simple mill energy balance that successfully predicts the coal throughput within 2.33% as compared to a calibrated coal feeder. A sensitivity analysis reveals that the coal moisture is a critical measurement for this method to be adopted as an on-line mass flow monitoring tool. A laser based particle size analyser tool was tested for use in the power plant environment as an online monitoring solution to measure pulverised fuel fineness. It was revealed that several factors around the set-up and operation of the instrument have an influence on the perceived results. Although the instrument showed good precision and repeatability of results, these factors must be taken into account in order to improve the accuracy of the reported results before the instrument can be commissioned as an on-line monitoring solution.
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Romanchenko, Sergey, Yuri Naganovskiy, and Anton Kornev. "Innovative ways to control dust and explosion safety of mine workings." Записки Горного института 252 (December 17, 2021): 927–36. http://dx.doi.org/10.31897/pmi.2021.6.14.
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Ensuring dust and explosion safety during underground coal mining is one of the most important tasks of industrial safety and labor protection departments. The main method of preventing explosions of coal dust settled in mine workings is to process them with stone dust (rock dusting). The traditional methods of quality control of rock dusting include radioisotope, optical and chemical methods. To implement them, the devices are equipped with environmentally harmful radioactive elements, expensive optical sensors, desiccants and replaceable flasks with chemical reagents, which increases the cost of analysis and its duration. The measurement error of these devices is 10 % or more. The main purpose of the study is to develop and substantiate a new method for monitoring the dust and explosion safety of mine workings, which will be devoid of the disadvantages of the methods mentioned above. It is proposed to evaluate the quality of rock-dust distribution by a fundamentally new way – thermogravimetric. The method was tested on the dust of coal mines in Kuzbass and the Vorkuta basin, including dust samples taken in mines with actual explosions. The article presents the results of experimental studies of the processes of thermal destruction of coal and stone dust mixtures. The non-overlapping intervals of the thermogravimetric reaction are identified: moisture yield (35-132 °С); volatile matter yield from coal (380-580 °С); thermal degradation of limestone with carbon dioxide yield (650-850 °С). Methods and mathematical dependencies for processing significant and qualitative identification characteristics of thermogravimetric curves in determining the content of non-combustible components in a sample of mine dust are considered.
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Samadhi, Tjokorde Walmiki, Tishi T. Daulay, M. Firmansyah, and Tjandra Setiadi. "Pembakaran ulang abu bawah batubara." Jurnal Teknik Kimia Indonesia 7, no. 3 (October 2, 2018): 810. http://dx.doi.org/10.5614/jtki.2008.7.3.1.
Повний текст джерелаАнотація:
The high carbon content of coal bottom ashes collected from several textile manufacturing plants in the Bandung area is indicative of an opportunity for energy utilization efficiency improvement by re-combustion of the bottom ashes. This research examines the technical feasibility of bottom ash utilization as a raw material for solid fuel briquette manufacturing. This paper discusses the measurement of the impact of bottom ash content on ignition time and crushing strength of the briquette. Bottom ash content is varied in the 0-50 %-weight range (binder and moisture-free basis). The ignition time of the briquette varies in the 4.4 – 9.9 minutes range. The ignition time of the briquette is proportional to its bottom ash content, due to the decrease in its volatile matter content. The crushing strength of the briquette varies in the 13.4 – 27.1 kgf/cm2 range, which is comparable to that of typical bulk sub-bituminous coals. A 10 %-weight addition of fresh coal powder to the briquette significantly increases its crushing strength, while further adition of coal powder does not significantly increase the crushing strength.Keywords : bottom ash, briquette, coal, energy efficiencyAbstrakTingginya kadar karbon dalam abu bawah batubara yang dihasilkan oleh boiler unggun tetap di sejumlah pabrik tekstil di wilayah Bandung mengisyaratkan peluang untuk meningkatkan efisiensi pembangkitan energi melalui pembakaran ulang abu bawah tersebut. Penelitian ini mengkaji kelayakan teknis pemanfaatan abu bawah sebagai bahan baku briket bahan bakar padat. Percobaan yang dilaksanakan bertujuan mengukur pengaruh kadar abu bawah dalam briket terhadap waktu penyalaan dan kekuatan mekanik produk briket. Kadar abu bawah divariasikan pada rentang 0-50 %-berat (basis bebas aditif perekat dan air). Waktu penyalaan briket berkisar pada 4,4 – 9,9 menit. Waktu penyalaan berbanding lurus dengan kadar abu bawah karena berkurangnya kadar zat terbang briket. Kuat remuk (crushing strength) briket berkisar pada 13,4-27,1 kgf/cm2, yang sepadan dengan kuat remuk batubara sub-bituminus bongkahan. Penambahan serbuk batubara segar sebesar 10 %-berat memberikan peningkatan kuat remuk yang signifikan, sementara penambahan lebih lanjut serbuk batubara segar tidak meningkatkan kuat remuk briket.Kata kunci : abu bawah, briket, batubara, efisiensi energi
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Watkinson, JH, A. Lee, and DR Lauren. "Measurement of elemental sulfur in soil and sediments - Field sampling, sample storage, pretreatment, extraction and analysis by high performance liquid chromatography." Soil Research 25, no. 2 (1987): 167. http://dx.doi.org/10.1071/sr9870167.
Повний текст джерелаАнотація:
A rapid method for measuring elemental sulfur (S0) in soil and sediments is described that is accurate and precise down to a detection limit of 0.1 mg kg-l. Elemental sulfur is extracted into chloroform and measured by high-performance liquid chromatography. For moist samples, water is added to exceed their liquid limit. The method has been used to follow oxidation of both natural and fertilizer So in soil in the laboratory and field. Sediments analysed included some from lakes, and settling ponds containing coal mine wastes. Extraction within the plastic range was incomplete and recoveries as low as 5%-65% were found for five soils selected for a wide range of plastic limit. The plastic soil aggregates were not dispersed in the water-immiscible chloroform, preventing the dissolution of occluded S0; but at moisture levels above and below the plastic range, the soil was dispersed and extraction of S0 was quantitative. Extraction into a water-miscible solvent, chloroform-methanol (50 : 50), dispersed the soil at all moistures by dissolving the water thus preventing formation of plastic soil. This was less convenient because either volume correction for moisture was needed, or excess water added later to separate the chloroform. Measurement of total sulfur (S) in chloroform by inductively coupled plasma gave comparable results where samples contained S0 fertilizer, but at the lower natural levels they were much less precise and sometimes higher because of the additional S compounds extracted. Storage of moist soil below -10�C or air-dry soil at 20�C, gave no loss of S0 after one month. Moist soil at 20�C gave 40% loss after one week, but at 4�C the loss was only 5% after four weeks. Forced air-drying at 30�C, freeze-drying and microwave drying (under a narrow range of conditions) gave losses of about 5% for fertilizer S0 (<0.15 mm fraction), and of about 20% for smaller S0 crystals. In field trials with S0, sample variability was associated mostly with the difficulty of applying the S0 uniformly and with the small number of particles applied per unit area. For particles <0.25 mm, variability from mixing of cores and sub-sampling was not so great.
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Syamsudin, Syamsudin, Katsushige Takami, Shoji Kita, Yusup Setiawan, Reza Bastari Imran Wattimena, and Andri Taufick Rizaluddin. "Studi Kasus Proyek Co-Benefit Peningkatan Efisiensi Boiler Batubara di Industri Kertas." JURNAL SELULOSA 10, no. 01 (June 30, 2020): 51. http://dx.doi.org/10.25269/jsel.v10i01.296.
Повний текст джерелаАнотація:
Pertumbuhan industri yang pesat menyebabkan masalah emisi gas rumah kaca. Kegiatan co-benefit peningkatan efisiensi boiler batubara telah dilakukan di industri kertas dalam proyek “Co-benefit Indonesia Tahun 2018” dari Kementerian Lingkungan Hidup Jepang dengan tujuan melakukan identifikasi langkah-langkah yang terkait dengan konservasi energi dan penurunan polutan emisi boiler industri berbahan bakar batubara dan cara melakukannya. Identifikasi meliputi analisis efisiensi termal boiler, pengukuran kadar air batubara, pengukuran kualitas air umpan boiler, air blowdown, dan kondensat, pemeriksaan insulasi panas, pengaturan rasio udara pembakaran, dan pengendalian operasi multi boiler. Berbagai kehilangan panas dianalisis dan beberapa rekomendasi diberikan untuk implementasi di pabrik sehingga efisiensi boiler dapat ditingkatkan. Beberapa masalah yang perlu diperbaiki untuk konservasi energi meliputi penggunaan batubara dengan kadar air tinggi, rasio udara pembakaran tinggi, konduktivitas air umpan tinggi menyebabkan rasio blowdown tinggi, tidak dilakukan insulasi pada mesin produksi yang relatif tua, dan pengoperasian beberapa boiler dengan efisiensi rendah. Potensi perbaikan melalui penyesuaian kadar air batubara, perbaikan rasio udara pembakaran, optimalisasi rasio blowdown, pemulihan air kondensat, pemasangan insulasi, dan kontrol multi boiler secara teori menghasilkan reduksi konsumsi batubara 16.445 ton/tahun atau 48,63%, dan reduksi CO2 sebesar 19.589 tCO2/tahun dengan estimasi penghematan biaya Rp 12 milyar/tahun. Kata kunci: co-benefit, industri kertas, boiler, batubara, emisi.Case Study of Co-Benefit Project Improvement of Coal Boiler Efficiency in The Paper IndustryABSTRACT Industrial rapid growth has caused greenhouse gas emissions problems. Co-benefit activities to improve the efficiency of coal boilers have been carried out in paper industry in the project of “Co-benefit Indonesia FY 2018” from the Japan Ministry of Environment aimed at identifying required steps to save energy and reduction of pollutant emission from the coal-fired industrial boilers and how to achieve it. Identification include analysis of boiler thermal efficiency, coal moisture content measurement, boiler feed water, blowdown water and condensate quality measurement, heat insulation examination, combustion air ratio management, and control of multiple boiler operations. Various heat losses have been analyzed and some recommendations have been proposed to be implemented by factory management to improve boiler efficiency. There are several issues that need to be addressed for energy conservation, namely: high water content coal utilization, high combustion air ratio, high conductivity feed water which causes high blowdown ratios, no insulation on relatively old production machines, and operational of several low efficiency boilers. The results of the co-benefit identification indicated that the potential for corrective action by adjusting the coal water content, improving the combustion air ratio, optimizing the blowdown ratio, recovering condensate water, installing insulation, and controlling multiple boilers theoretically can result coal consumption reduction of 16,445 tons/year or 48.63%, and CO2 reduction of 19,589 tCO2/year with an estimated cost savings of Rp 12 billion/year.
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Zhao, Bingchao, Yunxiang Ma, Yaxin Guo, Hao Sun, Jingbin Wang, and Hailong Wang. "Study and Application of Similar Material Ratio in Collapsible Loess." Advances in Materials Science and Engineering 2021 (December 24, 2021): 1–9. http://dx.doi.org/10.1155/2021/9736900.
Повний текст джерелаАнотація:
The similar material of collapsible loess is the basis and premise of the experimental study on the surface movement and deformation law of coal seam mining in collapsible loess-covered areas. The orthogonal experiment is used to make up similar material with different proportions using river sand and barite powder as aggregate, clay and gypsum as cementing material, and diatomite as adjusting material. The reasonable proportion of similar material in collapsible loess is studied by using range analysis, similar simulation, and field measurement. The results show that the content of diatomite plays a leading role in the collapsibility coefficient of similar material, and the collapsibility coefficient is positively correlated with the content of diatomite; moisture content is the main control of the cohesion of the material, and cohesion is negatively correlated with the moisture content; the ratio of bone-to-glue has the most significant effect on the internal friction angle, and the internal friction angle is positively correlated with the ratio of bone-to-glue. The reasonable ratio of the similar material in collapsible loess is 8 : 2 of the ratio of bone-to-glue, the ratio of clay-to-gypsum is 9 : 1, the barite powder content is 6%, the diatomite content is 23%, and the moisture content is 13%, and the mechanical parameters of the collapsible loess are 5.3%–6.3% different from the target value of similar material through laboratory tests, which can meet the experimental requirements. It is verified by a similar simulation experiment that the maximum surface subsidence value and the surface fracture width in the simulation results are 6.9% and 7.8% different from the field measured results, indicating a high degree of agreement. The results of the study have important references and guiding significance for the preparation of similar material with similar models.
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Vasylkivskyi, Vsevolod, Leonid Stefanovich, and Oksana Chesnokova. "INFLUENCE OF NATURAL MOISTURE ON THE CHARACTERISTIC TIME OF METHANE DESORPTION FROM COALS OF VARIOUS DEGREES OF METAMORPHISM." JOURNAL of Donetsk mining institute, no. 2 (2020): 23–32. http://dx.doi.org/10.31474/1999-981x-2020-2-23-32.
Повний текст джерелаАнотація:
Goal. To study the effect of natural internal moisture content on the kinetics of methane desorption from coals of varying degrees of metamorphization. Methodology. For the research, coal was used after a long (more than 100 days) preliminary exposure in a dry, closed indoors. The measurements were carried out on several samples of Donbass coals with different volatile content. Two groups of coal samples were used - dry, with natural internal humidity and one sample with artificial humidity of 1.5%. The volumetric method was used for measurements. The method includes three stages: 1st saturation of coal with compressed methane, 2nd preliminary discharge of compressed gas from a container with coal after its saturation, and 3rd collection of methane released by coal into a storage vessel. Before registration of desorption, pressurized gas was discharged from the free volume of containers into the atmosphere. The desorption unit contains a low-temperature trap (78°C) for water vapor and a warming radiator for methane entering the storage vessel. To determine the numerical values of the characteristic time of desorption of methane from coal, we used information on the change in gas pressure in the storage vessel during desorption. To analyze the results, a method based on the concept of a change in the characteristic relaxation time of desorption during methane emission was used. Results. Experimental results show that in wet coals the ratio between the amount of methane in coal and the intensity of its outflow at any desorption site is less than in dry coals. It was found that in coals of the metamorphic series the presence of natural moisture leads to a decrease in the intensity of methane emission, a decrease in the characteristic desorption time and a decrease in the activation energy of methane desorption by 0.4 - 2.5 kJ / mol. The features of the kinetics of desorption indicates competition energetics of interactions between methane and water with the surface of the pores of coal. Scientific novelty. It was found that even without artificial humidification, but in the presence of natural internal moisture in coal, the degassing time during desorption is reduced (in comparison with dry coal). Practical significance. The research results can be used to optimize the duration of hydraulic saturation of the coal seam and the water consumption during coal degassing.
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Dudzińska, Agnieszka, Mieczysław Żyła, and Janusz Cygankiewicz. "Influence of The Metamorphism Grade and Porosity of Hard Coal on Sorption and Desorption of Propane / Wpływ Stopnia Metamorfizmu I Porowatości Węgli Kamiennych Na Sorpcję I Desorpcję Propanu." Archives of Mining Sciences 58, no. 3 (September 1, 2013): 867–79. http://dx.doi.org/10.2478/amsc-2013-0060.
Повний текст джерелаАнотація:
Abstract In this paper results of investigations of sorption of hard coal samples collected from the extracted coal seams of Polish coal mines are presented. As sorbate propane was used. Examinations were carried out in the temperature of 298 K by means of volumetric assessment with the use of apparatus ASAP 2010 of Micromeritics. On the basis of conducted examinations it has been found out that the amount of sorbed propane depend on a type of coal, its metamorphism grade, content of oxygen element, moisture and porosity of these coals. The greatest amounts of propane are sorbed by low carbonized, high-porosity coals of high content of oxygen and moisture. Sorption of relatively high amounts of propane by these coals (ca. 10 cm3/g) is a result of the influence of polar surface of coals with molecules of propane and good availability of internal microporous structure of these coals for molecules of examined sorbate. Medium and high carbonized coals sorb insignificant amounts of propane. These coals have compact structure and non-polar character of their surface, their internal porous structure is to a minor degree available for propane molecules in conditions of carried out research. Sorption of propane in this case, takes place mainly in surface pores and on the surface of coals. Moreover, measurements of desorption isotherms of propane showing irreversible character of sorption were made. Desorption isotherms do not come together with sorption isotherms forming open hysteresis loop. Amounts of non-desorbing propane remaining in the coal depend on the type of examined coal.
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Karablin, Mikhail M. "Prediction of marginal rock mass stability in clays of Quaternary deposits including the effect of filtration reservoir by the example of the Bachat coal mine." Izvestiya vysshikh uchebnykh zavedenii. Gornyi zhurnal 1, no. 3 (May 14, 2021): 36–47. http://dx.doi.org/10.21440/0536-1028-2021-3-36-47.
Повний текст джерелаАнотація:
Introduction. During opencast mining, the development of mine workings in clays of Quaternary deposits is often accompanied by stability loss. As a rule, the reason for the development of geomechanical processes 46 "Izvestiya vysshikh uchebnykh zavedenii. Gornyi zhurnal". No. 3. 2021 ISSN 0536-1028 is the mismatch between the accepted geometry and physical-mechanical characteristics of soils. In case strength characteristics and moisture content are strongly related in the conditions of lacking water saturation sources, slopes remain stable for a long time. However, in the case of water saturation, soils change to plastic or liquid consistency, and the strength properties are reduced. In engineering practice, to prevent hazardous geomechanical processes, electrophysical methods are applied that make it possible to build the boundaries of soil moisture anomalies through electrical contrast. In the instances when the water-saturated strata occurrence depth and thickness is known from drilling and vertical electrical sounding data, electrical profiling makes it possible to promptly determine the variability of these characteristics of the anomaly. The authors proposed an algorithm of water-saturated strata thickness variability determination from the point of electrical profiling. Research aim is to predict the stability of the marginal rock mass in clays of Quaternary deposits, taking into account the effect of filtration reservoirs by combining engineering-geological databases and geophysical measurement results based on the 3D geological-geophysical model. Methodology includes the analysis of the engineering-geological databases and geophysical measurement results. Results. A 3D geological-geophysical model of the marginal rock mass with the boundaries of the watersaturated stratum was built from the results of the research to predict the stability of the marginal rock mass’s actual position. Slope stability analysis established the following: at design sections О3у3–О5у5 after deformation, retaining forces exceed shearing forces significantly (safety factor) because the weight of the base wedge grows due to landslide masses; potential landslide hazard area is associated with the design section О1у1, which is due to smooth fall of the stability factor from 1.38 (section О2у2) to 1.06, close to ultimate. Conclusions. For the extension of the marginal rock physical-mechanical properties variation it is appropriate to apply the method of electrical prospecting (sounding and profiling) determining watersaturated areas by local negative anomalies of effective electrical resistivity and establishing the function of loose Quaternary deposits thickness variation by the inversion of electrical profiling graphs with the use of the least square procedure and the golden section method. If landslide hazard areas are vast, the variation of the stability factor design values, which were determined based on 3D geological-geophysical models, may possess the non-monotonic character with several extreme values and significant gradients. For that reason, it is appropriate to carry out computerized analysis with a cyclic extension of the most hazardous areas by the coordinate of the profile and the direction of the design section in a plan.
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Huang, Chenlu, Qinke Yang, and Weidong Huang. "Analysis of the Spatial and Temporal Changes of NDVI and Its Driving Factors in the Wei and Jing River Basins." International Journal of Environmental Research and Public Health 18, no. 22 (November 12, 2021): 11863. http://dx.doi.org/10.3390/ijerph182211863.
Повний текст джерелаАнотація:
This study aimed to explore the long-term vegetation cover change and its driving factors in the typical watershed of the Yellow River Basin. This research was based on the Google Earth Engine (GEE), a remote sensing cloud platform, and used the Landsat surface reflectance datasets and the Pearson correlation method to analyze the vegetation conditions in the areas above Xianyang on the Wei River and above Zhangjiashan on the Jing River. Random forest and decision tree models were used to analyze the effects of various climatic factors (precipitation, temperature, soil moisture, evapotranspiration, and drought index) on NDVI (normalized difference vegetation index). Then, based on the residual analysis method, the effects of human activities on NDVI were explored. The results showed that: (1) From 1987 to 2018, the NDVI of the two watersheds showed an increasing trend; in particular, after 2008, the average increase rate of NDVI in the growing season (April to September) increased from 0.0032/a and 0.003/a in the base period (1987–2008) to 0.0172/a and 0.01/a in the measurement period (2008–2018), for the Wei and Jing basins, respectively. In addition, the NDVI significantly increased from 21.78% and 31.32% in the baseline period (1987–2008) to 83.76% and 92.40% in the measurement period (2008–2018), respectively. (2) The random forest and classification and regression tree model (CART) can assess the contribution and sensitivity of various climate factors to NDVI. Precipitation, soil moisture, and temperature were found to be the three main factors that affect the NDVI of the study area, and their contributions were 37.05%, 26.42%, and 15.72%, respectively. The changes in precipitation and soil moisture in the entire Jing River Basin and the upper and middle reaches of the Wei River above Xianyang caused significant changes in NDVI. Furthermore, changes in precipitation and temperature led to significant changes in NDVI in the lower reaches of the Wei River. (3) The impact of human activities in the Wei and Jing basins on NDVI has gradually changed from negative to positive, which is mainly due to the implementation of soil and water conservation measures. The proportions of areas with positive effects of human activities were 80.88% and 81.95%, of which the proportions of areas with significant positive effects were 11.63% and 7.76%, respectively. These are mainly distributed in the upper reaches of the Wei River and the western and eastern regions of the Jing River. These areas are the key areas where soil and water conservation measures have been implemented in recent years, and the corresponding land use has transformed from cultivated land to forest and grassland. The negative effects accounted for 1.66% and 0.10% of the area, respectively, and were mainly caused by urban expansion and coal mining.
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Widarsono, Bambang, Kosasih Sartadiredja, and Bambang A. Widjayanto. "Establishment Of More Reliable Equations For Estimation Of Coalbed Methane Proximate Analysis Data." Scientific Contributions Oil and Gas 32, no. 2 (March 17, 2022): 103–13. http://dx.doi.org/10.29017/scog.32.2.839.
Повний текст джерелаАнотація:
Coal bed methane (CBM) data such as ash contents, moisture contents, volatile matters, and fixed carbon – commonly obtained from log analysis - are direct input to calculation of gas accumulation in CBM reservoirs. However, recent studies on some coal samples taken from Rambutan field CBM pilot project have shown that the commonly used log analysis equations are simply inapplicable for the field’s coal samples. Calculation results tend to give far different magnitudes when compared to laboratory results. After a series of re-evaluations and re-measurements on the laboratory results it was convinced that the problem does not lie with the laboratory results but with these ‘conventional’ equations. Therefore modification efforts are spent to find better equations. Comparisons between measured data (coal samples taken from two coal seams in the field) and calculated data show that only equation for ash contents gives accurate results. The other proximate analysis output data - i.e. moisture contents, volatile matter, and fixed carbon – is at considerable odd with their corresponding calculated data. Modification upon the original empirical models is then carried out. The following modifications on the equations have produced analogous but different empirical equations to the original equations. These equations certainly work more reliably for the field’s coals, and these better results underline that future log analyses in the field have to use the modified equations
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Siebert, H. M., Thore Rohwerder, Wolfgang Sand, M. Strzodka, and K. P. Stahmann. "Evidence for Iron- and Sulfur-Oxidizing Bacteria and Archaea in a Currently Active Lignite Mining Area of Lusatia (Eastern Germany)." Advanced Materials Research 71-73 (May 2009): 97–100. http://dx.doi.org/10.4028/www.scientific.net/amr.71-73.97.
Повний текст джерелаАнотація:
The largest lignite mining area in Europe is located 150 km southeast of Berlin. Acidic lakes exist in this area, known to be caused by marcasite oxidation. Thirty-two samples from the open-pit brown coal-mine Jaenschwalde were analyzed for microorganisms. Cell numbers determined after separation from sand particles revealed concentrations of 102 to 107 microorganisms per g sample. In samples exposed to the air within an hour, up to 4x107 cells were counted. Measurement of metabolic activity by microcalorimetry showed for such samples up to 50 µW per g sand, whereas in heap samples (with low moisture) low or even no activity was measurable. DNA extraction was successful for 28 samples. In 26 samples microbial 16S rRNA genes were amplified by PCR. Acidithiobacillus ferrooxidans and At. thiooxidans specific amplificates were detected by nested PCR in 23 and 10 cases, respectively. A specific signal indicating Leptospirillum ferrooxidans was obtained with nine samples. Random samples were sequenced and showed 96 to 99 % identity with published data of all three species. Surprisingly, in four samples archaeal 16S rRNA genes were amplified by PCR. Sequencing of two samples showed 99 % identity with unidentified or uncultured archaea found in NCBI-databases. Molecular biology results for At. ferrooxidans as well as for At. thiooxidans were supported by successful isolations of pure cultures in 23 cases. Cultivation of the archaea failed so far. These data indicate that iron- and sulfur-oxidizing microorganisms occur at these sites in large numbers. If in addition the evidence for archaea can become verified, a screening for hot spots as the sites of their occurrence would become interesting.
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Misra, B. K. "Tertiary coals of Makum Coalfield, Assam, India: Petrography, genesis and sedimentation." Journal of Palaeosciences 39, no. (1-3) (December 31, 1990): 309–26. http://dx.doi.org/10.54991/jop.1990.1697.
Повний текст джерелаАнотація:
The two most important coal seams, viz., Seam no. 1 (18 m thick) and Seam no. 3 (6 m thick), of the Tikak Parbat Formation, Barail Group (Oligocene) are overlain by > 2000 m thick sediments of younger age. The coals are bright and non-banded in appearance. They are rich in vitrinite with subordinate amounts of liptinite and inertinite macerals. Early diagenetic pyrite and calcite alongwith clay and quartz are the main associated minerals. Under blue light excitation high amount of fluorescing macerals recorded are formed chiefly by perhydrous Vitrinite, liptodetrinite and resinite. Minor amount of sporinite, cutinite, suberinite and exsudatinite are also present with sporadic occurrence of f1uorinite and alginite. A comparison of Makum coals with the other Tertiary coals of India has also been attempted. The coals have low moisture and ash contents with high volatile matter and calorific value in relation to their rank by reflectivity measurements. The rank of the coal seams (R0 max. 0.72-0.75%) corresponds to high volatile bituminous B stage.
From the biopetrological, palaeobotanical and geological evidences it has been concluded that the coal seams originated mostly from in situ mangrove-mixed angiospermous forest vegetation growing under humid to per-humid tropical climate. The vegetal accumulation took place in a rheotrophic swamp forming in a near-shore lagoon on a lower delta plain. The maceral and mineral associations in the coal seams indicate that the accumulated vegetal matter was mainly subjected to anaerobic microbial degradation under elevated swamp water pH (> 6). This facilitated the precipitation of early diagenetic pyrite, calcite and in situ release of plant-derived minerals in the peat. Under these conditions highly pyriteous and perhydrous coal seams were formed mainly by putrefaction. Whenever microbial degradation of organic matter was severe normal vegetal supply fell short to produce a peat layer, with the result minor and major authigenic partings within the coal seams were formed.
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Li, Teng. "The Dynamic Change of Pore Structure for the Low-Rank Coal with Various Pretreatment Temperatures: A Case Study from Southwestern Ordos Basin." Geofluids 2020 (July 1, 2020): 1–13. http://dx.doi.org/10.1155/2020/8879742.
Повний текст джерелаАнотація:
The pore characteristics of the low-rank coal are different from medium- and high-rank coals. The low-temperature N2 adsorption (LP-N2A) measurements with a single low-rank coal were launched, and the dynamic change of pore structures under various pretreatment temperatures from 120°C to 300°C was studied. The isothermal curves of the DFS coal sample feature IV type, the hysteresis loops convert from H4 type to H2 type, and the hysteresis loops tend to be closed with the increased pretreatment temperatures. The mesopores are dominant in the DFS coal. The dynamic of pore volume (PV) and pore specific surface area (SSA) features the three-step-style change with the cut-off temperature points at 150°C and 240°C, and this has a relationship with the loss of the moisture and volatiles in the DFS coal sample. The pores with an aperture below 10 nm are the dominant mesopores in the DFS coal, and the mesopore volume features bimodal pattern distribution with a higher left peak of approximately 1.7 nm and a lower right peak of approximately 3-5 nm, and the right peak continuously right shift with the increase pretreatment temperatures. The total mesopore volume decreases with the upgrading temperatures, while the ratio of pores greater than 5 nm increases. Finally, the mesopore evolution model with the increased pretreatment temperatures was summarized.
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Battistutta, Elisa, Ali Akbar Eftekhari, Hans Bruining, and Karl-Heinz Wolf. "Manometric Sorption Measurements of CO2 on Moisture-Equilibrated Bituminous Coal." Energy & Fuels 26, no. 1 (December 6, 2011): 746–52. http://dx.doi.org/10.1021/ef2012936.
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Holmes, Ralph. "The ongoing challenge of representative sampling of bulk mineral commodities." TOS Forum 2022, no. 11 (May 27, 2022): 303. http://dx.doi.org/10.1255/tosf.159.
Повний текст джерелаАнотація:
Sampling of bulk mineral commodities for international trade, such as iron ore, coal and a wide variety of mineral concentrates, is generally carried out in accordance with National or more commonly International (ISO) Standards developed to provide representative samples for subsequent analysis and payment. Because commercial transactions are involved, clearly getting the sampling right is critically important, and poor sampling practices can potentially lead to substantial financial losses for one of the parties involved. The “golden rule” for correct sampling is that “all parts of the material being sampled must have an equal probability of being collected and becoming part of the final sample for analysis”. If this rule is not respected, then bias is easily introduced and samples are not representative. While on-site observations indicate that the adoption of good sampling practices is improving, ensuring that samples are representative continues to be an ongoing challenge. This is often due to cost-cutting measures where sampling facilities, equipment and operations are the first to suffer, or it may just simply be due to ignorance of the requirements for collecting representative samples despite the existence of National and International Standards as well as high level sampling courses presented by international experts. More often than not, the company focus is on maximizing production tonnage rather than product quality and its measurement. Areas where significant issues continue to occur include: Primary cutter design for ever increasing high-capacity streams Correct operation of cross-stream secondary cutters Crusher performance and ongoing maintenance, particularly in relation to product particle size Retained sample mass versus particle size Extraction and handling of moisture samples Equipment maintenance. Timely ongoing maintenance of sample stations is critical and needs to be a high priority to ensure correct performance. A“set and forget” strategy simply does not work. Sampling needs to be given the commitment it deserves by company management, particularly through correct sample plant design, timely equipment maintenance, and appropriate staff training and awareness.
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Dam G., Oscar. "Comparative study on the un test n` 5 application on cargoes that emit flammable gases similar to dri c that requires ventilation." Athenea 1, no. 1 (September 26, 2020): 41–51. http://dx.doi.org/10.47460/athenea.v1i1.5.
Повний текст джерелаАнотація:
This technical note summarizes a technical comparison of common testing procedures, as well as reviewed of the UN Test N` 5, for the assessment of the self-heating properties of cargoes and materials that has shown a clear trend on maritime fire and explosions events, as well as considering of external factors that can combine self-heating and emit flammable gases to conclude in an unlikely event affecting the security of crews and ships. A high understanding of the external factors effect on the cargo materials certainly will help the application of spontaneous reactions management actions (SRMA) on board of ships during the cargo sea passage. The intended comparison is based on laboratory, industry and field observations and data, whereas the among the external factors considered are, moisture content, stockpile procedure and aging, air velocities and moderate pressures internal and externally to the cargo material. The comparison results have shown that the self-heating and the flammable gas emissions has a common pattern when reacting with any oxygen available source, regardless the reactive material chemical composition.
Keywords: reactive materials, self-heating, self-ignition, direct reduced iron fines, materials handling, UN test N` 5, maritime safety, spontaneous reactions, risk management. IMSBC Code , IMO.
References
[1]A. M. DeGennaro, M. W. Lohry, L. Martinelli, C. W. Rowley. Uncertainty Quantification for Cargo Hold Fires. Princeton University, Princeton, NJ, 08540, USA. American Institute of Aeronautics and Astronautics.
[2]L.L.Sloss Assessing and Managing Spontaneous Combustion of Coals. IEA Clean Coal Center (CCC 259). Oct. 2015.
[3].A. Janes, G Marlair, D Carson, j. Chaneausx. Towards the improvement of UN Test N1 5 Method for the characterization of substances which in contact with water emit Flammable Gases. Journal of Loss Prevention in the Process Industries. Elsevier 2012, 25 (3), pp 524-534.
[4]G. Rouget, B. Majidi, D. Picard, G. Gauvin, D. Ziegler, J. Mashreghi, and H. Alamdar. Electrical Resistivity Measurement of Petroleum Coke Powder by Means of Four-Probe Method. Metallurgical and Materials Transactions B. Vol. 48B, Oct. 2017-2543.
[5]Y. Rubiela Hernández Puerto, M.Triviño Restrepo. El coque metalúrgico aplicado a protección catódica (Metallurgia coque applied to catodic protection). Revista del Instituto de Investigaciones FIGMMG. Vol. 10, Nº 20, 60-67 (2007) UNMSM I.
[6]S. Narayan Jha, K. Narsaiah, A.L. Basediya, R.Sharma, P. Jaiswal, R. Kumar, and R. Bhardwaj. Measurement techniques and application of electrical properties for nondestructive quality evaluation of foods—a review. Food Sci Technol. 2011 Aug; 48(4): 387–411.
[7]R. Fontes Araujo, J. Batisa Zonta, E. Fontes Araujo, E. Heberle, E, F. Miranda Garcia Zonta. Teste de Conductividade Eletrica para Smentes de Feijao Mungo Verde 1. Rev. Brasikleira de Sementes, Vol. 33, N` 1, pp123/130, 2011.
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[9]N. Birks, et.al. - Mechanism in Corrosion Induced Auto-ignition of Direct Reduced Iron. Materials Science and Engineering Department, University of Pittsburgh.
[10]Monitoring Implementation of the Hazardous and Noxious Substances Convention. Report on incidents involving HNS. Submitted by the United Kingdom. IMO 85th Session, Agenda item 5- LEG 85/INF.2, 19 September 2002.
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Prieto-Fernández, Ismael, J. Carlos Luengo-Garcia, Manuela Alonso-Hidalgo, and Belen Folgueras-Diaz. "Adjustments of Microwave-Based Measurements on Coal Moisture Using Natural Radioactivity Techniques." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 28, no. 1 (January 2006): 97–103. http://dx.doi.org/10.1080/009083190889681.
Повний текст джерела
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Dębowski, Marcin, Przemysław Bukowski, Przemysław Kobel, Jerzy Bieniek, Leszek Romański, and Bernard Knutel. "Comparison of Energy Consumption of Cereal Grain Dryer Powered by LPG and Hard Coal in Polish Conditions." Energies 14, no. 14 (July 19, 2021): 4340. http://dx.doi.org/10.3390/en14144340.
Повний текст джерелаАнотація:
The calculation method commonly used in the industry takes into consideration mainly fuel consumption (excluding electricity) and the amount of removed moisture which is reflected in the unit MJ·(Mg·%)−1. This is not a scientific approach because the result will change if the basic moisture is different (drying from 21% to 18% will consume less energy than drying from 18% to 15%). This paper aims to compare the energy consumption of two industrial continuous flow grain dryers powered by LPG and hard coal based on a comprehensive approach to energy efficiency calculation enriched with electricity consumption, flow measurements, and control of grain moisture. It could be useful for manufacturers who could use this method to generate more reliable data in their product datasheets, and it could also be legally regulated as an appropriate tool for calculating the energy consumption of agricultural grain dryers. According to the approach presented in this paper, the S428.CS construction powered by LPG gas had an energy consumption that was 6.14% lower than the DT2532 dryer construction, which used hard coal.
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Zhang, Chuan, Xiang Bin Xu, and Qing Song Zhang. "Preparation and Properties of a New Type of Coal Dust Suppressant." Materials Science Forum 1036 (June 29, 2021): 145–49. http://dx.doi.org/10.4028/www.scientific.net/msf.1036.145.
Повний текст джерелаАнотація:
A new type of water-soluble coal dust suppressant (later called MA) with excellent performance was prepared by modified starch, styrene, methyl methacrylate, Butyl acrylate (as the main monomers) and acrylic acid (as the functional monomer) via mixed the emulsifiers of Sodium dodecyl sulfate (SDS)/octylphenol polyoxyethylene(10)ether (OP-10) and ammonium persulfate served as initiator. The properties of anti-wind erosion, water retention and coal quality impact were investigated. The MA was characterized by viscosity measurements and scanning electron microscopy. The results show that the spraying of MA has no effect on coal quality, and the water loss rate of MA is slightly lower than that of water, which has certain moisture retention. After spraying MA on the surface of coal sample for 120 hours, the coal sample is swept by six-stage wind (wind speed is 10.8-13.8 m/s), and the erosion rate is only 1.8%. The MA and coal samples are closely bonded to form a dense soft film, which has a excellent dust suppression effect.
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Roux, L. "A critical review of initial Resource and Reserve tonnage estimation and reporting." Journal of the Southern African Institute of Mining and Metallurgy 121, no. 11 (November 30, 2021): 1–10. http://dx.doi.org/10.17159/2411-9717/1427/2021.
Повний текст джерелаАнотація:
This review was initially motivated by the author's own experience in attempting to reconcile run-of-mine production tons with the Coal Resource and Reserve estimation of mineable, in-situ tonnages. The primary scientific measurements and observations that are collected during exploration at the beginning of the value chain will have a profound effect on the future of the mining operation. Due diligence must be exercised during the planning of a new mine and during the life of an existing mine. The comments provided by the technical and economic assessment group of Venmyn Deloitte confirmed the need for this critical review. They found the reporting of Coal Resources in South Africa to be inconsistent. This was particularly problematic in the Waterberg Coalfield in Limpopo Province. In this coalfield there are two types of coal deposit present. The first is comprised of the thick intercalated, cyclic coal and shale/mudstone sequences of the Volksrust Formation. This overlies multiple coal seams within the Vryheid Formation, each of which is thick enough to be extracted as an individual raw coal unit. On the other hand, the interbedded coal and shale seams of the Volksrust Formation require beneficiation to separate the coal from the shale. The review examines practices and methods, investigates alternatives, provides checks and balances, and tests these against actual production reconciliations. In conclusion, the best estimates of the mineable, in-situ tonnage will be obtained from the air-dry raw material density. These estimates should be adjusted afterwards to allow for free moisture content. The adjustments are derived from reconciliation data. The greatest contributing factor to the over-estimation of Reserve tonnages is the moisture content of the raw material. This fluctuates significantly under varying conditions in situ, as well as upon exposure to the natural environment. The air-dried density of the raw material includes inherent (structurally bound) moisture within the matrix. It provides credible tonnage estimations of raw material available while also providing an indication of voids within the volume of material being assessed. The calculated solids percentage can be used to adjust the specific gravity, which is determined via the Archimedes principle. This will supply a representative estimate of the material to be mined.
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Rybalkin, L. A., and I. M. Serdyuk. "Development of a methodology to research the influence of liquid nitrogen exposure on carbon material." Interexpo GEO-Siberia 2, no. 3 (May 18, 2022): 300–306. http://dx.doi.org/10.33764/2618-981x-2022-2-3-300-306.
Повний текст джерелаАнотація:
Recently, studies, which are dedicated to the effect of cryogenic substances on the structure of coal, are gaining popularity. The impact of liquid nitrogen on coal leads to micro- and macrostructural disturbances in the continuity of coal due to drastic cooling of the moisture in the microcracks and pore space of the coal, while the volume of ice microcrystals increases. This approach provides the opportunity to treat the massif without additional injection of liquid agents into seams to create pressure to disintegrate it, unlike traditional methods of increasing the filtration surface in coal. Research work, which are presented in this field, are aimed at studying the multiplicity of increase in porosity and fracturing of coal in the process of single or multiple exposure to portions of liquid nitrogen. A distinctive feature of the ongoing research is the evaluation of the results of cryotreatment of samples by non-destructive methods of measuring the pore space. Thus, the conclusion about the change in permeability is made without direct measurements of the gas filtration rates in the samples. Changes shown by CT scans show an increase in the total number of open pores and channels, however they do not illustrate the increase in gas permeability in general. As a part of this work, we carried out a number of studies on axial gas filtration in dense coal samples, which were under controlled all-round loading. Preparatory work was carried out to dry the samples and further saturate them with moisture to identical values in the entire batch. A scheme for conducting experiments to study the effect of cryotreatment on the internal structure of coal using the methods of stationary axial gas filtration and NMR relaxometry is proposed. The development of this technique contributes to obtaining reliable data on the increase in the gas permeability of coal samples. The data can be useful in designing methods and approaches to increase the degree of degassing by treating degassing wells at coal mining enterprises.
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Kardaś, Dariusz, Sylwia Polesek-Karczewska, Przemysław Ciżmiński, and Sławomir Stelmach. "Prediction of coking dynamics for wet coal charge." Chemical and Process Engineering 36, no. 3 (September 1, 2015): 291–303. http://dx.doi.org/10.1515/cpe-2015-0020.
Повний текст джерелаАнотація:
Abstract A one-dimensional transient mathematical model describing thermal and flow phenomena during coal coking in an oven chamber was studied in the paper. It also accounts for heat conduction in the ceramic oven wall when assuming a constant temperature at the heating channel side. The model was solved numerically using partly implicit methods for gas flow and heat transfer problems. The histories of temperature, gas evolution and internal pressure were presented and analysed. The theoretical predictions of temperature change in the centre plane of the coke oven were compared with industrialscale measurements. Both, the experimental data and obtained numerical results show that moisture content determines the coking process dynamics, lagging the temperature increase above the water steam evaporation temperature and in consequence the total coking time. The phenomenon of internal pressure generation in the context of overlapping effects of simultaneously occurring coal transitions - devolatilisation and coal permeability decrease under plastic stage - was also discussed.
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Prisecaru, Tudor, Adrian Adam, Lucian Mihăescu, Ionel Pîşă, Elena Pop, Malina Prisecaru, Viorel Berbece, and Mihai Dragne. "Combustion Experiments On A Solid Fuel With Low Sulphur Content." E3S Web of Conferences 180 (2020): 01015. http://dx.doi.org/10.1051/e3sconf/202018001015.
Повний текст джерелаАнотація:
Research was carried out at the experimental installation defined by the 2 MW furnace pilot from the Politehnica University of Bucharest and ICEMENRG institute who was involved for measurements. The purpose of the experimental study is to confirm that the use of a coal with low sulphur content S<0.08% is possible without the use of sulphurpurification installations for industrial purposes. But, the high moisture content of the coal has imposed the problem of its compatibility with a certain milling technology. The pilot plant is equipped with fan mill and pre-drying tower. Under these conditions, this installation allows the grinding of fuels with high moisture content. The experiments focused on the process of ignition, combustion and pollutant emissions, with the exemplification, in particular, of the emission of sulfur dioxide. Also, the outbreak temperatures and the slugging temperature were monitored. For this purpose, the outbreak of the pilot boiler was equipped with all the equipment necessary to follow these parameters. The experiments have shown positive aspects to the burning of this fuel, thus laying the foundations of future tests at industrial installations (first of all, the power plant from Deva is considered).
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Saha, Nepu, Akbar Saba, Pretom Saha, Kyle McGaughy, Diana Franqui-Villanueva, William Orts, William Hart-Cooper, and M. Reza. "Hydrothermal Carbonization of Various Paper Mill Sludges: An Observation of Solid Fuel Properties." Energies 12, no. 5 (March 5, 2019): 858. http://dx.doi.org/10.3390/en12050858.
Повний текст джерелаАнотація:
Each year the pulp and paper industries generate enormous amounts of effluent treatment sludge. The sludge is made up of various fractions including primary, secondary, deinked, fiber rejects sludge, etc. The goal of this study was to evaluate the fuel properties of the hydrochars produced from various types of paper mill sludges (PMS) at 180 °C, 220 °C, and 260 °C. The hydrochars, as well as the raw feedstocks, were characterized by means of ultimate analysis, proximate analysis, moisture, ash, lignin, sugar, and higher heating value (HHVdaf) measurements. Finally, combustion indices of selected hydrochars were evaluated and compared with bituminous coal. The results showed that HHVdaf of hydrochar produced at 260 °C varied between 11.4 MJ/kg and 31.5 MJ/kg depending on the feedstock. This implies that the fuel application of hydrochar produced from PMS depends on the quality of feedstocks rather than the hydrothermal carbonization (HTC) temperature. The combustion indices also showed that when hydrochars are co-combusted with coal, they have similar combustion indices to that of coal alone. However, based on the energy and ash contents in the produced hydrochars, Primary and Secondary Sludge (PPS2) could be a viable option for co-combustion with coal in an existing coal-fired power plant.
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Discepolo, Dakota R., Russell Kelley, Jamie Wayman, Elizabeth Fuess, and Erin B. Perry. "PSI-3 An assessment of the barrier function of canine skin after repeated decontamination." Journal of Animal Science 99, Supplement_3 (October 8, 2021): 274. http://dx.doi.org/10.1093/jas/skab235.502.
Повний текст джерелаАнотація:
Abstract Working canines are often deployed to environments with unknown chemical and biological contaminants. Deployed canines may operate in highly contaminated disaster sites for lengthy periods of time requiring daily decontamination efforts. The skin provides a barrier by retaining moisture and preventing entry by contaminants and pathogens. However, few data exist on the impact of repeated decontamination to the canine skin. The objective of this study was to identify changes in dermal health during and after a 14-day serial decontamination program. Labrador retrievers (n = 8) were decontaminated daily using a dish detergent solution (1:8, detergent:water). Skin measurements were collected weekly for pH, trans-epidermal water loss (TEWL), sebum, and moisture. Additionally, visual assessments were recorded for skin health, coat condition, and dander scores (back and body). Statistical tests were conducted with SAS (version 9.4) with measurements analyzed using a PROC GLM Two Way ANOVA and visual assessments analyzed using PROC FREQ Chi Square test. Significance was set at 5% for all tests. Repeated decontamination significantly increased TEWL (P < 0.0001) through day 16. Sebum content was also impacted by repeated daily decontamination efforts (P = 0.0387). Sebum decreased initially before steadily rising. In contrast, moisture content (P = 0.3842) and pH (P = 0.7462), were unaffected by repeated decontamination. Interestingly, dander scores assessed on the back were worsened by repeated decontamination (P = 0.0222) but dander scores assessed across the whole body were unaffected (P = 0.1804). Coat shine was unaffected by decontamination (P = 0.1156) similar to coat softness (P = 0.3418). Overall coat condition remained unchanged as a result of repeated decontamination efforts (P = 0.9466). These data reveal that daily decontamination impacts dermal function, potentially risks for canines working in contaminated areas. Future work should include investigations into methods for decontamination to mitigate these risks.
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Scullion, J., A. R. A. Mohammed, and G. A. Ramshaw. "Statistical evaluation of drainage treatments in simple field trials with special reference to former opencast coal mining land." Journal of Agricultural Science 107, no. 3 (December 1986): 515–20. http://dx.doi.org/10.1017/s0021859600069665.
Повний текст джерелаАнотація:
SUMMARYDrainage trials frequently lack any statistical evaluation of treatment differences, often because of practical difficulties in setting up randomized field experiments. Also, where detailed moisture measurements are carried out the usefulness of such data is small in relation to the workload involved. Procedures are described here which seek to rectify, in part, the above limitations.Routine drain and surface condition data were analysed. Parallel regression analysis was used to compare drainage response patterns based on linear relationships between rainfall and peak drain flow. A point scoring system allowed treatment effects on surface conditions to be evaluated by x2 analysis.Artificial drainage seeks to simulate naturally free-draining conditions. In line with this objective, soil moisture contents in the field, on a ‘Field Capacity Day’ (Stewart & Adams, 1968), were related to those at a standard (– 10 KPa) moisture tension typical of free-draining reference sites. Effectiveness of drainage performance was indicated by proximity of field and reference tension moisture contents.Worked examples of each of the above procedures are provided. The procedures were found to be both sensitive and complementary. The value of the overall approach and its application under more normal agricultural conditions are discussed.
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Kornarzyński, Krzysztof, and Bożena Gładyszewska. "Evaluation of the Moisture Change Ability of Selected Crop Seeds." Agricultural Engineering 21, no. 1 (March 1, 2017): 59–68. http://dx.doi.org/10.1515/agriceng-2017-0006.
Повний текст джерелаАнотація:
Abstract The objective of the paper was to investigate the moisture change ability of bean, broad bean, pea, lupine, radish, beetroot, winter wheat, maize, cucumber, pumpkin and sunflower seeds. Seeds absorbed water in the system for measurement of the water absorption kinetics with the capillary and weighting method. The research results were presented in the form of plots of the relation of kinetics of the moisture change of seeds in the time for the first and second stage of the process which precedes germination. Moreover, the water content in seeds for the time of the end of the second stage of water absorption was determined and the maximum water absorption speed coefficient and the time of its obtaining was calculated. The water content for the end of the 2nd stage of its collection was the highest for seeds which include a hard caryopsis and for broad bean plant seeds. The maximum water absorption speed coefficient was the highest for seeds with low initial moisture - radish, beetroot, cucumber and pumpkin. The measurement of the water absorption speed with the use of the capillary and weighting method enabled investigation of seeds with a varied size, construction of a seed coat and chemical composition for a long period of time to the moment seedlings were obtained.