Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collections

Permanent URI for this collectionhttps://hdl.handle.net/20.500.13091/3

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Citation - WoS: 50
Citation - Scopus: 55
Advanced Oxidation of Landfill Leachate: Removal of Micropollutants and Identification of By-Products
(ELSEVIER, 2021) Ateş, Havva; Argun, Mehmet Emin
Landfill leachate contains several macropollutants and micropollutants that cannot be removed efficiently by conventional treatment processes. Therefore, an advanced oxidation process is a promising step in post or pre-treatment of leachate. In this study, the effects of Fenton and ozone oxidation on the removal of 16 emerging micropollutants including polycyclic aromatic hydrocarbons (PAHs), phthalates, alkylphenols and pesticides were investigated. The Fenton and ozone oxidation of the leachate were performed with four (reaction time: 20-90 min, Fe(II) dose: 0.51-2.55 g/L, H2O2 dose: 5.1-25.5 g/L and pH: 3-5) and two (ozonation time: 10-130 min and pH: 4-10) independent variables, respectively. Among these operating conditions, reaction time played more significant role (p-value < 0.05) in eliminating di-(2-Ethylhexyl) phthalate, 4-nonylphenol and 4-tert-octylphenol for both processes. The results showed that Fenton and ozone oxidation processes had a high degradation potential for micropollutants except for the PAHs including four and more rings. Removal efficiencies of micropollutants by ozone and Fenton oxidation were determined in the range of 5-100%. Although the removal efficiencies of chemical oxygen demand (COD) and some micropollutants such as phthalates were found much higher in the Fenton process than ozonation, the degradation products occurred during the Fenton oxidation were a higher molecular weight. Moreover, the oxidation intermediates for the both processes were found as mainly benzaldehyde, pentanoic acid and hydro cinnamic acid as well as derivatives of naphthalenone and naphthalenediol. Also, acid ester with higher molecular weight, naphthalene-based and phenolic compounds were detected in the Fenton oxidation.
Citation - Scopus: 4
An Analysis and Countermeasures of Fatal Accidents Caused by Firedamp Explosions in Underground Coal Mines in Turkey
(2019) Dursun, Arif Emre
Fatal accidents in underground coal mines in Turkey are common and experienced frequently. The major accident categories for underground coal mining in Turkey are gas related accidents (firedamp and outbursts), roof falls, flooding, fire and transport. In recent years, coal mine gas related accidents in Turkey, which are usually caused by firedamp and outbursts, are still threatening miners’ lives. Firedamp explosions are majorly serious mine accidents that can occur quickly and cause great deal damage. In this study, work-related accidents caused by firedamp and another gas accidents in Turkey between the years 2010-2016 were analyzed. As a result of these analyses, the number of deaths in underground coal mines in the past 7 years is 550 and the fatality rate is found to be 96.86%. The percentage of gases as the cause of the deaths is 70.18%. In this study, countermeasures are proposed that can prevent and control firedamp explosions and other gas related accidents.
Citation - WoS: 16
Citation - Scopus: 17
Assessment of Natural Radioactivity Level of Soil and Water in the Region of Corlu (turkey)
(SPRINGER, 2021) Manisa, Kaan; Erdoğan, Mehmet; Usluer, Ali; Çetinkaya, Hakan; Işık, Ulaş; Şahin, Latife; Zedef, Veysel
The activity concentrations of Rn-222 with an AlphaGUARD system in well having different depths and in natural spring waters were measured to assess the natural radioactivity level of the corlu region. The measured concentrations varied from 22.04 to 63.92 Bq L-1 for 6 well water samples, 15.38-24.33 Bq L-1 for 6 spring water samples. The activity concentrations from U-238, Th-232 and K-40 in 11 soil samples collected from the same region were also determined and the outdoor gamma dose rates at 1 m above the surface at the same sampling points were measured. The results obtained in this study lie within safe limits recommended by WHO and UNSCEAR with the exception of the mean specific activity of K-40 radionuclide.
Citation - WoS: 2
Citation - Scopus: 4
Assessment of the Effect of Blasthole Design Parameters on Total Cost in Quarries
(SPRINGER HEIDELBERG, 2020) Bilim, Niyazi; Çelik, Arif; Kekeç, Bilgehan
Crushed stone is the most important raw material for concrete and asphalt production. As a high-volume low-unit-value industry, the crushed stone production sector is highly competitive which implies the necessity to optimise the costs of all of its production operations, i.e. drilling and blasting, secondary breaking, loading, hauling and crushing. In this context, this paper investigates the effect of bench blasting design parameters on the unit-costs and total production cost of aggregate production. For this purpose, 40 blasts were conducted and investigated. The studied parameters included different blasthole length (12 m, 15 m, 18 m, 21.5 m and 25 m) and diameter (89 mm and 102 mm), in addition to different spacing, burden and stemming length. As a result, it was found that an increase in blasthole length led to an increase in the unit cost of drilling operation. In addition, it was found that a blasthole length of 15 m ensured optimum fragmentation, diminishing the costs of subsequent operations. Incrementing the blasthole diameter from 89 to 102 mm reduced the total unit cost by 0.091 $/m(3). Incrementing the burden and spacing by 0.25 m also decreased the total unit cost by 0.097 $/m(3). However, accreting the stemming length by 0.5 m induced a slight decrease in the total unit cost by 0.026 $/m(3).
Assessment of Work Accidents in Highway, Street and Bridge Construction
(International Multidisciplinary Scientific Geoconference, 2018) Bilim, Atiye; Çelik, Osman Nuri
Occupational health and safety is an important work discipline that must be included in the working life. Especially, developed countries have been able to place this discipline in working life, while developing countries have still problems. These problems take place both in terms of legislation and practice. The situation is similar to that of developing countries, in Turkey. The construction sector is in line with the development status of a country. The construction sector contributes both directly and indirectly to the country's economy. It has become indispensable for the economy of a country with its share in employment and it stimulates production of goods and services related to the sector. The construction sector is not just about building constructions. We also need bridges, metros and high-speed train lines. Transports have a major contributor to the development of a country. In parallel with technological developments, large investments related with transports become increase. Due to the revival in this sub-sector, the number of work accidents has also tended to increase. Therefore, the work accidents in the highway, street and bridge constructions, which are the sub-activities of the construction sector, must be examined. In this study, work accidents in the sector were analyzed for Turkey and U.S. Also, the share of the sector in total work accidents and construction accidents were determined for Turkey and U.S. The causes of fatal work accidents in highway, street and bridge constructions were mentioned. © 2018, International Multidisciplinary Scientific Geoconference. All rights reserved.
Citation - WoS: 36
Citation - Scopus: 43
Comparison of Advanced Biological Treatment and Nature-Based Solutions for the Treatment of Pharmaceutically Active Compounds (phacs): a Comprehensive Study for Wastewater and Sewage Sludge
(ELSEVIER, 2021) Nas, Bilgehan; Dolu, Taylan; Argun, Mehmet Emin; Yel, Esra; Ateş, Havva; Koyuncu, Serdar
Passing of pharmaceutical residues into environment in an uncontrolled manner as a result of continuous increase in drug consumption across the globe has become a threatening problem for the ecosystems and almost all living creatures. In this study, diclofenac (DCF), carbamazepine (CBZ), 17 beta-estradiol (17 beta-E2) and 17 alpha ethynylestradiol (EE2) belonging to different therapeutic classes were investigated simultaneously in advanced biological treatment and nature-based treatments during 12-months sampling campaign. In this context, behavior patterns of pharmaceutically active compounds (PhACs) throughout the both wastewater and sludge lines in advanced biological wastewater treatment plant (WWTP), wastewater stabilization pond (WSP) and constructed wetland (CW) were discussed in detail based on each treatment processes seasonally. Furthermore, statistically evaluated data obtained in full-scale WWTPs were compared with each other in order to determine the valid removal mechanisms of these pharmaceutical compounds. While DCF and CBZ were detected very intensively both in the wastewater and sludge lines of the investigated WWTPs, steroid hormones,17 beta-E2 and EE2, were determined below the LOQ value in general. Annual average removal efficiencies achieved in studied WWTPs for DCF ranged between & minus;23.3% (in CW) and 75.2% (in WSP), while annual average removal rates obtained for CBZ varied between & minus;20.7% (in advanced biological treatment) and 10.0% (in CW). It has been found that DCF was highly affected by different wastewater treatment processes applied in the WWTPs compared to CBZ which showed extraordinary resistance to all different treatment processes. Although calculated in different rates for each compounds, biodegradation/biotransformation and sorption onto sewage sludge were determined as the main removal mechanisms for PhACs in plants. Although showed a similar behavior in the sludge dewatering unit (decanter) present in the advanced biological WWTP, quite different behaviors ob-served in the anaerobic digester for DCF (up to 15% decrease) and CBZ (up to 95% increase). Sorption and desorp-tion behaviors of DCF and CBZ were also evaluated in the sludge treatment processes found in advanced biological WWTP. Percentages of originated extra annual average of pharmaceutical loads were calculated as 0.64% and 0.90% for DCF and CBZ, respectively in the advanced biological WWTP due to the sidestream caused by the sludge dewatering unit. (c) 2021 Elsevier B.V. All rights reserved.
Citation - WoS: 12
Citation - Scopus: 12
Effect of Organic and Inorganic Compounds on Dissolution Kinetics of Chalcopyrite in Hydrogen Peroxide- Hydrochloric Acid System
(Elsevier, 2022) Abdelraheem, Mohamed Taha Osman; Agacayak, Tevfik
The addition of 2-Propanol as an organic substance and NaCl as an inorganic com-pound in hydrochloric acid with hydrogen peroxide as a strong leaching agent of chalcopyrite was investigated. The effects of the leaching parameters on copper extraction, such as stirring speed, H2O2 concentration, temperature, HCl concentration and solid/liquid ratio were studied. The max-imum final copper extraction of 54.55% was obtained with 600 rpm stirring speed, 1.5 M H2O2, 0.5 M HCl, 600 rpm, 50 C, 240 min of the reaction and particle size of -106 +75 mm. Further experiments were performed when the solid-to-liquid ratio (S/L), stirring speed, temperature, HCl,H2O2 and leaching time were kept constant to examine the influence of NaCl and 2-Propanol concentrations in the range of 0-0.5 M and 0-3 M, respectively. The results showed that the copper extraction was increased up to 58.11% with addition of NaCl. While copper extraction yield reached 94.25% in case of addition of 2-propanol with the optimum parameters(0.5 M HCl,50 C, 1.5 M H2O2, 600 rpm, particle size -106 +75 lm, solid liquid ratio 2g/L, 3 M 2-propanol). The chalcopyrite leaching in hydrogen peroxide- hydrochloric acid system was found to be described by the interface transfer and diffusion across the product layer with activation energy of 77.14 kJ/mol. Addition of 2-propanol suggested that the reaction was under product layer diffusion control and decreased the activation energy of chalcopyrite leaching to 67.98 kJ/mol. Crown Copyright (c) 2022 Published by Elsevier B.V. on behalf of King Saud University.
Estimation of Concrete Lining Thickness for Stability of Circular Mine Shafts in Different Rock Masses
(CRC Press/Balkema, 2020) Özkan, İhsan; Hussaini, S.S.
In this study, in each of the nine-meter-diameter shafts which has different depths (100, 300, 500, 700 and 900 meters), the M-RMR values were considered as 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 respectively. In addition, it was assumed that the uniaxial compressive strength (?ci) was 50 MPa and also was D = 0 and D = 0.5 for situation formed in surrounding rocks based on blasting. The under condition, the numerical analyses were made by Phase2 software. As a result, in this parametric study, a total of 100 scenarios were analysis. The optimum thickness (tc, m) of concrete support with C20 class concrete have been identified for each scenario. The maximum principal stresses (?1, MPa), total displacement (U, mm), the number of yielded elements formed in the surrounding rocks, strength factor (SF) and thickness of yielded region (ht,, m) respectively were determined. Using Phase2 software 10 integrated charts were prepared. if the rock mass classification value (M-RMR) is known, the thickness of yielded surrounding rocks (ht, m), concrete support thickness (tc, m), the total displacement (U, mm) to be occur in the shaft can be determined by the integrated charts. Also, for (M-RMR) vs ht (m) and (M-RMR) vs U (mm) behaviors expressed in the integrated charts, two mathematical models were developed using SPSS software. © 2020 ISRM.
Citation - WoS: 6
Citation - Scopus: 7
Estimation of Specific Energy and Evaluation of Roadheader Performance Using Rock Properties and Bond Work Index
(SPRINGER HEIDELBERG, 2021) Özşen, Hakan; Dursun, Arif Emre; Aras, Ali
Specific energy (SE) is defined as the amount of work required to cut a unit volume of rock and is used to estimate the performance of excavation machines. Generally, the SE value is produced from full-scale or small-scale rock cutting tests. However, these tests require expensive equipment and experienced personnel, and the testing procedure is time consuming and impractical. Therefore, for estimation of SE, this study aimed to find a solution to estimate SE using rock mechanics test results and Bond work index values (BWi), which can be produced in a more practical, less time-consuming manner and with inexpensive test equipment. Small-scale rock cutting, rock mechanics and Bond work index tests were carried out on seven rock samples, which can be grouped into two different type of rocks: marble and travertine. In addition, the instantaneous cutting rates (ICR) of a selected roadheader were calculated using SE values. Rock mechanics tests performed in this study were uniaxial compressive strength (UCS), Brazilian tensile strength (BTS), ultrasonic velocity (V-p), Schmidt rebound hardness (R-L), corrected point load index (I-s(50)) and density (rho). The simple regression method was used to estimate SE from rock properties and BWi. As a result of this simple regression, a significant and highest correlation was found between SE vs. UCS and I-s(50). A good correlation was found between SE vs. BTS, R-L and BWi values. A moderate correlation was found between SE vs. V-p and rho.
Citation - WoS: 5
Citation - Scopus: 7
Estimation of the Risk of Work-Related Accidents for Underground Hard Coal Mine Workers by Logistic Regression
(TAYLOR & FRANCIS LTD, 2022) Bilim, Niyazi; Bilim, Atiye
Coal mining has the most risk in all of the mining sectors. Hence, in this sector, most work accidents encountered are intensive. The demographic characteristics of workers affect the occurrence of occupational accidents. This study aims to develop an equation that predicts workday loss by analyzing the relationship between workers' demographic characteristics and having an accident with workday loss. In this study, work-related accidents between 2014 and 2019 in underground hard coal mines in Turkey were analyzed using logistic regression analysis. An equation is derived that estimates the workday loss with the characteristics of workers in hard coal mines. With the equation derived in this study, employers can determine the potential for work accidents according to the demographic characteristics of the workers and serious work accidents will be prevented. Therefore, proactive solutions can be produced by applying the methods used in this study to different industries.
Evaluation Of Heavy Metal Content Of Salts Between Eskıkışla And Ocakbaşı (kırıkkale) Villages
(2021) Horasan, Bilgehan Yabgu; Öztürk, Alican
Salt, which is the main nutrient, is a very important raw material in the life of living organisms and industry. Salt production and consumption have improved and increased due to technological developments and industrialization. Salt has been used in the world and in our country since very ancient times. It is used in many fields, especially in the chemical industry, metallurgy, textile, medicine, and agriculture. In addition to sea, lake and spring salts, Turkey has very rich rock salt reserves. The Neogene aged Çankırı-Çorum Basin is one of the important basins where evaporitic formations are observed in the Central Anatolia region. Chemical analyses were carried out to determine the amount of heavy metal in salt samples taken from Oligocene aged units observed in the area between Ocabaşı and Eskikışla springs (Delice) in the Çankırı-Çorum basin. SEM-EDX, XRF and ICP-OES devices were used to determine the geochemical properties and quantities of heavy elements. According to the results of XRF, Na % ( 33.70-38.30), Cl %(52.10 - 57.70) SO3 %(0.75-1.93), Al2O3 %(0.90-1.93), CaO %(0.58- 2.69), MgO %(0.40-1.41) Fe2O3 % (0.18-0.64), SiO2 %(1.75-4.95), SrO, % (<0.010), BaO % (<0.010), Cr2O3 %(<0.010), K2O %(0.008-0.25), MnO %(<0.010) results are found. In the determination of heavy metals made with ICP-OES, it was determined that the heavy metals (Hg, As, Pb, Cd) published in the Turkish food codex salt communiqué were below the limit values.
Citation - WoS: 17
Citation - Scopus: 19
Fate of Pahs Under Subcritical and Supercritical Conditions in Landfill Leachate: Removal or Formation?
(ELSEVIER SCIENCE SA, 2021) Ateş, Havva; Argun, Mehmet Emin
In this study, fate of eight polycyclic aromatic hydrocarbons (PAHs) described as priority pollutants by the European Union during the subcritical and supercritical water oxidation (SCWO) of landfill leachate was investigated. The experiments were conducted under the temperature of 250?500 ?C, pressure of 10?35 MPa, residence time of 2?18 min and dimensionless oxidant dose (DOD) of 0.2?2.3. The results revealed that the SCWO process had a high potential for degradation of PAHs except for four and more rings from leachate having high organic and inorganic pollutant loads. The removal efficiencies of chemical oxygen demand (COD), naphthalene (NAP), anthracene (ANT) and fluoranthene (FL) increased up to 98%, 97%, 95%, and 87%, respectively. However, the high removal efficiencies of COD did not directly correlate with the removal of PAHs. 2- to 4-ring PAHs increased in subcritical and supercritical conditions at 0.4 DOD. Additionally, PAH compounds such as pyrene and chrysene not found in raw leachate were detected in some treated samples at low DOD and high temperature. It was concluded that aromatic substances detected in the leachate could transform to naphthalene, anthracene and fluoranthene with merger/separation reactions. On the other hand, aldehyde, ketone and phenol-based compounds were detected as the transformation products when the oxidation mechanism was dominant. Therefore, optimum experimental conditions that aimed to both minimize PAHs formation and maximize COD removal were determined as 7 min, 2 DOD, 375 ?C and 22.5 MPa.
Citation - WoS: 2
Citation - Scopus: 2
The Geological-Geochemical Characteristics of the Binbir Church (karaman, Turkey) Archaeological Site and the Alteration of the Rocks Used in the Buildings
(Springer, 2022) Horasan, Bilgehan Yabgu; Yüksel, Onur; Öztürk, Alican
Karaman (Turkey) province, formerly known as Lykaonia, has a wide range of geographically diverse raw materials, has hosted many civilisations throughout history, and provides remains of these civilisations to the present day. The area where the ruins of Madensehir and Degle villages are located, namely, in the northern part of Karadag (Karaman, Turkey) is called Binbir Church. This area, which has been understood as a sacred centre since the Hittites period, has strategic importance in terms of its geographical location in the Late Roman and Byzantine periods. It also became the most significant religious centre of the region during the Byzantine period. The building stones used in the basilicas numbered 1, 31, and 32 in the villages of Madensehir and Degle, located in the ruins of a thousand and one churches, are dacite, trachydacite, and trachyandesite. SiO2-poor andesite and dacites were used in the structures, and it was understood that these rocks were very slightly or slightly altered according to the degree of alteration using the weathering index (of parker), the chemical index of the alteration, chemical index of weathering and the plagioclase index of alteration. The study of this region, which is a cultural heritage, is expected to lead to significant contributions to long-term restoration works to be carried out in the region.
Citation - WoS: 5
Citation - Scopus: 4
Improvement of Colemanite Flocculation With Collectors by Ultrasound Treatment
(TAYLOR & FRANCIS INC, 2022) Özkan, Alper; Eşmeli, Kiraz
In this study, the influence of ultrasound on the stability of colemanite suspension was first studied without reagents, and the effects of ultrasound power value, treatment regime (batch and continuous), probe immersion depth, and treatment time on the suspension stability were determined. Then, the effects of ultrasound on the flocculation of colemanite with sodium dodecyl sulfate, Aero 845, and sodium oleate were investigated, and changes occurred in the flocculation efficiency, zeta potential and contact angle values were shown depending on the collector concentration. The experimental findings revealed that the application of ultrasound reduced the suspension stability; that is, enhanced flocculation of colemanite particles occurred due to the ultrasonic promotion. By the ultrasonic treatment, the contact angles measured on the mineral surface in the presence of these collectors increased. In addition, the ultrasonic treatment led to increases in the surface charge of colemanite mineral with these surfactants. These results indicated that the ultrasound increased the adsorption of collectors on the mineral surfaces, as a result of this, the hydrophobization of the colemanite surfaces improved, and thus the flocculation of colemanite enhanced.
Citation - WoS: 2
Citation - Scopus: 2
Improvement of Lignite Flocculation by Ultrasound Pre-Treatment and Performance Optimization Using Box-Behnken Design
(Taylor & Francis Inc, 2022) Esmeli, K.
There were two objectives of this study. The first was to investigate the influence of ultrasound treatment on coal flocculation in the presence of polymers. In this context, it was observed that the flocculation success increased by using ultrasound as a pre-treatment, but flocculation did not occur with its application in the flocculation phase (ultrasound-induced flocculation only). Also, the short-term application of ultrasound pre-treatment at high power created a more positive effect. In the flocculation process with polymers, the use of ultrasound treatment as a pre-treatment for the suspension enhanced the aggregation of coal particles. In addition, the ultrasound pre-treatment reduced the magnitude of the zeta potential of coal with anionic polymer, which also supported the flocculation. The second objective of the study was to determine the influence of variables related to stirring speed, flocculation time, polymer concentration, and pH on flocculation efficiency by using Box- Behnken design. With the Box-Behnken design, it was found that the optimal conditions for flocculation efficiency were a stirring speed of 300 rpm, a flocculation time of 4 min, a polymer concentration of 1 mg/L, and pH-7, and these values were consistent with experimental results.
Citation - WoS: 3
Citation - Scopus: 2
Improvement of Lignite Oil Agglomeration by Ultrasound Process Using Waste Engine Oil
(Taylor & Francis Inc, 2022) Esmeli, K.
In the present study, it was aimed to clean fine coal with waste engine oil using the ultrasound process. The influence of ultrasound on the oil agglomeration of coal was determined using ultrasound at the pretreatment stage and at the agglomeration stage. In this context, the use of ultrasound at the pretreatment stage improved the oil agglomeration of coal, but the use of ultrasound at the agglomeration stage reduced the recovery of combustible matter. Also, the power of ultrasound and the time of treatment affected the success of agglomeration, and the optimal values were achieved at a power of 30 W of ultrasound and a treatment time of 3 min. In addition, the best ash content and combustible matter recovery values were obtained at the oil dosage value of 3 mL, but higher oil dosages adversely affected the success of agglomeration. Under optimal conditions, coal with an ash content of 15.02% was obtained with an efficiency of 61.29% in conventional experiments, while coal with an ash content of 9.65% with ultrasound pretreatment was obtained with an efficiency of 71.04%. These results show that ultrasound pretreatment is an effective method for the enrichment of fine particle coal.
In-Situ Application of Schmidt Hammer Test on a Coal Face With Large-Scale
(CRC Press/Balkema, 2020) Mesutoğlu, M.; Özkan, İ.
Schmidt hammer (SH) is widely used to predict uniaxial compressive strength (UCS) and other mechanical properties of rocks from surface rebound hardness values. The method has been extensively applied to the intact rocks so far and for this reason, the researchers have developed some methods for use in rock cores and blocks. At the same time, there is not enough information about the in-situ application of the Schmidt hammer. In this study, SHs were carried out in Tunçbilek-Ömerler underground coal mine. For this reason, four measurement areas were prepared on the longwall face. The measurement areas were firstly divided into a grid system, with each grid section having an area of 0.214 m2. At the end of the study, two hundred and fifty-five records were constructed using the data obtained from 4 longwall face positions, and also these were used for statistical analyses. The obtained results were compared with the approaches suggested by ISRM (2007), ASTM (2005) and Young & Fowell (1978). © 2020 ISRM.
Citation - WoS: 8
Citation - Scopus: 8
Indoor Radon Activity Concentration and Effective Dose Rates at Schools and Thermal Spas of Ilgin
(VINCA INST NUCLEAR SCI, 2020) Erdoğan, Mehmet; Abaka, Murat; Manisa, Kaan; Bircan, Hasan; Kuş, Coşkun; Zedef, Veysel
Indoor radon activity concentrations and radon doses on the ground floor and basement floor of 19 schools (kindergardens, primary schools, secondary schools, and high schools) and thermal spas of Ilgin district in Konya, have been measured using the AlphaGUARD PQ 2000PRO radon detector, for three days in the first half of 2016. According to the results, while the indoor radon concentration for only one location, in total, is above the Turkish action level of 400 Bqm(-3), the values for 10 locations are above the reference level of 100 Bqm-3, recommended by WHO. The calculated annual effective doses for inhalation of the radon in indoor air were also found to be 0.26 mu Sv for the minimum and 4.36 mu Sv for the maximum. The parametric distribution analysis is also performed with 3-parameter Weibull distribution and some remarks are provided on radon concentration activity.
Citation - WoS: 8
Citation - Scopus: 9
An Insight on the Impact of Covid-19 on the Global and Turkish Mining Industry
(Ios Press, 2022) Kekeç, Bilgehan; Bilim, Niyazi; Ghiloufi, Dhikra
BACKGROUND: COVID-19 affected numerous industries and the mining industry has not been immune to the adverse impacts caused by the pandemic. OBJECTIVE: This study examines the importance of the mining industry and its benefits to the economy of the producing countries. The paper also gives an insight into the pre-COVID global and Turkish mining industries and investigates the impact of the pandemic on the global and Turkish mining sectors. Furthermore, the study suggests numerous measures that should be adopted in mines to limit the spread of COVID-19 and conduct mining operations safely and efficiently. METHODS: An extensive literature review was conducted and relevant papers on the importance and benefits of the mining industry, the Turkish and global mining industry, and the impact of COVID-19 on the Turkish and global mining industry were studied. RESULTS: The COVID-19 crisis has deeply affected metal and mineral production and the economic sectors that depend on the mining industry for supplies. The most significant impacts caused by the COVID-19 pandemic on the global mining industry consist of the drastic decline in demand and production and the decrease in the prices of several commodities. As with any complex global situation, the mining industries of some countries were affected more than others by the COVID-19 crisis. The Turkish mining industry was to some extent affected by the COVID-19 crisis, but it quickly recovered. CONCLUSIONS: An efficient planning of operations and adopting effective measures and precautions enable limiting the spread of COVID-19 in quarries and mines.
Citation - WoS: 3
Citation - Scopus: 3
Investigation of Ash Removal From Fine Grain Coal-Water Suspension by Hydrophobic Flocculation Using Taguchi (l-16) Experimental Design
(Taylor & Francis Inc, 2022) Ağaçayak, Tevfik
In this study, it was aimed to remove ash from fine-grained coal-water suspensions and a series of hydrophobic flocculation experiments were performed using the Taguchi (L-16) experimental design to determine the experimental optimum conditions. Five different controllable process variables such as amount of sodium silicate, suspension pH, amount of waste vegetable oil, flock growth time, and precipitation time, which are effective in hydrophobic flocculation of coal, and four different levels of each variable were investigated. Optimum conditions were determined as amount of sodium silicate 1 mL, pH = 3, amount of waste vegetable oil 4 mL, flock growth time 7 min and precipitation time 1 min. According to the optimization results obtained, the high calorific value (5450 kcal/kg) clean coal with 15.46% ash content and 100% combustible recovery was obtained with 57.52% ash removal. In addition, the contributions of each factor to hydrophobic flocculation of coal were determined with one way variance analysis (ANOVA). The most influential factor was determined as the pH value with a contribution of 61.34%.

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