İlgi alanları

Sürdürülebilir Kalkınma Amaçları

• 8
• 3
• 1

• MakaleAçık Erişim2026Scopus SJRQ1/r/bayburt/11430
  Optimization of surface modification parameters of calcium carbonate in the rotary-vibration mill with a fuzzy-based taguchi experimental method

  Özdemir, Akın; Uçurum, Metin

  Ultra-fine calcium carbonate (UCC) is used as a filler material in polymers, and after a surface modification (coating) process, its surface changes from hydrophilic to hydrophobic. However, conventional coating techniques such as raymond and pin mills are widely used in the industry; there is still a need for new, inexpensive, and practical methods. Mechanochemical technologies are considered one of the most effective alternatives. The rotary-vibration mill (RVM) works mechanically and is characterized by low investment and operating costs. There are three main contributions in this paper. First, a fuzzy-based Taguchi experimental design is proposed to analyze a fuzzy response under uncertainty. Second, the surface modification of UCC with stearic acid was carried out using RMV, with five modification parameters and an active ratio fuzzy response. Moreover, the results indicate that RVMs are an alternative mechanochemical surface modification technology for preparing coated calcium carbonate (CCC). Finally, particle size distribution (PSD), contact angle, XRD (X-Ray Diffraction Analysis), TGA-DTA (Thermogravimetric Analysis-Differential Thermal Analysis), FTIR (Fourier Transform Infrared Spectrophotometer), and SEM (Scanning Electron Microscopy) analyses were conducted for the coated calcium carbonate (CCC) acquired from the optimum conditions of the modification study.

  İncele
• MakaleYalnız künye2025Scopus SJRQ1/r/bayburt/11030
  Optimization of surface modification parameters of fly ash with high calcium oxide (CaO) content to use as a filling material

  Uçurum, Metin; Özdemir, Akın; Teke, Çağatay

  Fly ash (FA) is the fine-grained waste product obtained by burning coal after being ground to specific sizes in thermal power plants, carried with flue gases, and kept in cyclones or electro-filters. Like every industrial waste, the possibilities of utilizing FA have been investigated, and it can be utilized as an additive in cement and concrete. Despite this, industrial waste, which increases daily in the world, brings many problems, especially environmental problems. For this reason, alternative usage areas of the waste in question are constantly being investigated. In this paper, FA containing approximately 50 % CaO from Afşin-Elbistan, Turkiye was processed with stearic acid in a planetary mill to be used as a filling material in industrial products, and it has a grain size of 68.10 μm on a d50 basis, a specific surface area (SSA) of 176.40 m2/g and a contact angle of 13.89. An optimization and characterization study was conducted to make the hydrophilic surface structure hydrophobic by mechanochemical surface modification. Also, surface modification parameters, such as operational speed (rpm), ball filling ratio (%), FA filling ratio (%), pulp density, stearic acid dosage (% of FA), and modification time (min.) were optimized with the D-optimal experimental design. Based on the optimum surface modification parameters, a coated fly ash (CFA) product was obtained with an active ratio of 99.70 %, a contact angle of 95.06o, a medium size (d50) size of 10.60 μm, and an SSA of 926.90 m2/g.

  • 
  AtıfScopus8·WoS8·OpenAlex9

  İncele
• MakaleYayıncıda açık erişim2024Scopus SJRQ1/r/bayburt/13085
  Wet mechanochemical surface modification of calcite employing an integration of conventional design and analytical hierarchy process

  Uçurum, Metin; Özdemir, Akın

  The demand for ultra-fine mineral powders from various industries requires the applications of wet grinding and surface modification. In this study, wet mechanochemical surface modification of micronized calcite (d50 = 4.92 μm) with stearic acid [CH3(CH2)16COOH] was carried out in a planetary ball mill. The seven parameters were specified: ball filling ratio (%), ball size distribution ratio (10 and 15 mm, %), micronized calcite filling ratio (%), pulp solid ratio (wt%), mill speed (rpm), stearic acid dosage (% of micronized calcite) and modification time (min). Then, these parameters were optimized using a conventional experimental design when maximizing the active ratio (%) as a significant value for coated calcite. Besides, the analytical hierarchy process was applied to observe the importance of each parameter. Stearic acid dosage, mill speed, and micronized calcite filling ratio are the top three parameters affecting the active ratio. Next, size distribution, XRF, XRD, SEM, FTIR, TGA-DTA, contact angle, and whiteness measurements were performed on the micronized calcite (MC) and coated micronized calcite (CMC) samples. The final CMC product had a 99.90% active ratio, 2.49 μm mean (d50) particle size, and 101.66o contact angle. Finally, CMC obtained by the surface modification can be used as a filler mineral.

  AtıfScopus6·WoS4·OpenAlex7

  İncele
• MakaleAçık Erişim2024Scopus SJRQ1/r/bayburt/12821
  Optimization of mechanochemical surface modification parameters on planetary mill using an I-optimal experimental design

  Özdemir, Akın; Uçurum, Metin

  Several micro-particle-size additives and filler minerals are added to many industrial products, especially plastic, in order to reduce cost and improve mechanical properties and appearance. Also, grinding and surface modification are two fundamental properties of the filler minerals used in plastic products. Notably, Bayburt stone (BS) used as a natural raw material from Bayburt, Türkiye contains 76% SiO2 and 15% Al2O3. In this paper, the hydrophilic surface structure of micronized Bayburt stone (MBS) was made hydrophobe by mechanochemical surface modification using calcium stearate [Ca(C17H35COO)2] in a laboratory-type planetary mill. Next, the optimum conditions of the surface modification design factors, which are (1) ball filling ratio = 30.53%, (2) powder filling ratio = 10.43%, (3) mill speed = 475.91 rpm, (4) chemical dosage = 1.99% of powder, and (5) modification time = 4.83 min., were obtained using the proposed I-optimal design-focused optimization model when predicting the model parameters. In addition, a coated micronized Bayburt stone (CMBS) product with an active ratio (AR) of 99.90% and d10, d50, and d90 values of 1.32 μm, 3.48 μm and 9.55 μm were achieved. Finally, particle size distribution (PSD), thermo-gravimetric and differential thermal analyzer (TG-DTA), Fourier transform infrared (FTIR), scanning electron microscope (SEM), electron dispersive spectrum (EDS), and contact angle analyses were performed on the CMBS product.

  • 
  AtıfScopus5·WoS6·OpenAlex6

  İncele
• MakaleYalnız künye2024Scopus SJRQ1/r/bayburt/11680
  A Novel Fuzzy Cumulative Sum Control Chart with an α-Level Cut Based on Trapezoidal Fuzzy Numbers for a Real Case Application

  Özdemir, Akın; Uçurum, Metin; Serencam, Hüseyin

  Statistical process control (SPC) is widely used to monitor production processes in many industries under certain conditions. When dealing with a quality characteristic for uncertainty, fuzzy numbers are used in the context of the statistical process control (SPC) to monitor a fuzzy production process. The aim of this paper is fourfold. One, a fuzzy X¯-R control chart with an α-level cut is used based on trapezoidal fuzzy numbers (TFNs) for detecting the large shifts in the fuzzy process mean. Second, a fuzzy cumulative sum (FCUSUM) control with an α-level cut based on TFNs is firstly developed for detecting the small shifts in the fuzzy process mean. Third, the fuzzy process capability indices (FPCIs) are presented to measure the fuzzy process performance. Finally, an ultra-fine calcite production process is controlled with both the fuzzy X¯-R control chart and the proposed FCUSUM control chart. The results of the fuzzy X¯-R control charts show that the fuzzy production process is in control, and large shifts in the fuzzy process mean were detected. On the other hand, the results of the FCUSUM charts show that the fuzzy production process is out of control, and small shifts in the fuzzy process mean were detected. FPCIs are also conducted, and the results of fuzzy Cpk indices show that the ultra-fine calcite production process is not capable of meeting specification limits.

  AtıfScopus7·WoS9·OpenAlex9

  İncele
• MakaleAçık Erişim2023/r/bayburt/15651
  Combination of Conventional Ball Mill and Stirred Mill to Obtain Ultra-Fine Talc

  Uçurum, Metin; Güleç, Ömer; Toraman, Oner Yusuf

  In this study, it was investigated that talc ore could ground to very fine sizes using a combination of conventional ball mill and vertical stirred mill. Firstly, the conventional ball mill parameters such as mill speed (% of critical speed), material filling ratio (Jb), ball filling ratio (fc), ball size distribution (10-20-30-40 mm, %), grinding aid ratio (% of powder) and grinding time (min.) were optimized using classic experimental design. As a result of the optimization, fine talc product was obtained with d90=93.52 µm particle size. In the second stage, the ball mill product was re-milled using a stirred mill. As a result of study, a final ultra-fine talc powder was obtained after 60 minutes grinding time with d50=1.85 µm particle size and 14058 cm2/g total surface area. It has been seen that the conventional ball mill+stirred mill combination effective a process to obtain talc powder that suitable for industrial use.

  • 
  İncele
• MakaleAçık Erişim2021Scopus SJRQ1/r/bayburt/13452
  Development of a Fuzzy Exponentially Weighted Moving Average Control Chart with an α-level Cut for Monitoring a Production Process

  Kaplan Göztok, Kader; Uçurum, Metin; Özdemir, Akın

  Statistical quality control is a useful approach that applies to statistical techniques for monitoring a production system. These charts are effective to monitor the process under certain conditions. On the other hand, the fuzzy set theory is an appropriate tool to deal with an uncertain situation. This paper is fourfold. First of all, triangular fuzzy numbers with an α-level cut technique are used for each sample. The α-level cut technique is sensitive to satisfy the process requirement. Second, a fuzzy exponentially weighted moving average (FEWMA) control chart is proposed with the α-level cut technique. The proposed FEWMA detects small shifts under uncertain situations while using a unity technique for samples. Third, the fuzzy target-focused process capability index (FCpm) index is proposed to measure the fuzzy process performance. Then, a case study is presented to monitor a pumice block plant using the FEWMA control chart with the α-level cut and measure the process performance with the FCpm index. Comparative studies are also presented. By using the proposed FEWMA control chart with the α-level cut, the accuracy and the flexibility of control specification limits are reported for the case study.

  AtıfScopus9·WoS8·OpenAlex7

  İncele
• MakaleAçık Erişim2021Scopus SJRQ3/r/bayburt/13310
  A novel approach to finding optimum operating conditions of design factors for the grinding experiment

  Uçurum, Metin; Özdemir, Akın; Teke, Çağatay; Tekin, İlker

  The efficiency of grinding experiments is an important issue for many industries. In this paper, a central composite design-based methodology was proposed to investigate the four design factors that affect the particle sizes. The four design factors were specified as mill speed (% of Nc), ball filling ratio (fc), powder filling ratio (jb) and grinding time (min). Another important issue was how to obtain an optimum operating condition for four design factors. For this particular purpose, a novel dual response optimization model was proposed using the particle sizes (d 10, d 50, and d 90) and the span value concept. This proposed approach was compared to the desirability function-based optimization concept. The verification study of the experiment was also carried out. The results of the grinding experiment runs showed that the optimum operating conditions were mill speed 73.495% of Nc, ball filling ratio 0.354, powder filling ratio 0.157, and grinding time 70 min. In addition, d 10, d 50, and d 90 were found 3.31 µm, 12µm, and 45.6 µm, respectively. The span value was also found at 3.52.

  AtıfScopus3·WoS3·OpenAlex4

  İncele
• MakaleAçık Erişim2021Scopus SJRQ3/r/bayburt/13309
  A novel weighted mean-squared error optimization model to obtain optimal conditions of adsorption factors for a lead removal process

  Özdemir, Akın; Teke, Çağatay; Serencam, Hüseyin; Uçurum, Metin; Gündoğdu, Ali

  Lead (Pb) removal process from wastewater is an important issue to prevent health problems for people. For this particular purpose, a low-cost adsorbent may be beneficial for improving the adsorption capacity for the Pb removal process. The aims of this paper are four-fold. First of all, a D-optimal experimental design was selected to reduce experimental runs and its cost. Second, the effect of four adsorption design factors, stirring speed (rpm), adsorbent dosage (g), pH level, and initial metal concentration (ppm), was examined. Also, the yellow natural stone, which is from Bayburt, Turkey, was used as a cheap adsorbent for the Pb removal process from the solu-tion. Third, a novel weighted mean-squared error optimization model was developed to obtain optimal adsorption levels for adsorption factors. Besides, a verification study was conducted to verify the results of the adsorption experiment. Finally, the lead (Pb(II)) removal capacity of the yellow Bayburt stone was obtained to be 46.031 mg/g, and the results of the experiment from the proposed methodology showed a good performance for the removal study.

  • 
  • 
  İncele
• MakaleAçık Erişim2020/r/bayburt/14961
  Bulanık İstatistiksel Proses Kontrol Tekniği ile 19x39x19 cm Bims Hafif Yapı Malzemesi Üretiminin Analizi

  Uçurum, Metin; Kaplan Göztok, Kader; Özdemir, Akın

  İstatistiksel Proses Kontrolü (İPK), üretim çıktılarının ürün özelliklerini belirlenen kalite aralıklarındayapılmasını kontrol eden, sağlayan ve standart dışı üretimin önüne geçmede mühendislerin kullandığı en önemlimatematik esaslı bir araçtır. Ancak konvansiyonel İPK yöntemlerinin yetersiz kaldığı durumlarda bulanık kümeteorisinden yararlanılan daha hassas istatistiksel proses kontrolüne imkân veren bulanık istatistiksel proseskontrol yaklaşımları geliştirilmiştir. Bu makalede, bir Bims fabrikası ürünü olan 19x39x19 cm Bims ürünününüretim sürecin kontrol altında olup olmadığının belirlenmesinde bulanık istatistiksel proses kontroltekniklerinden yararlanılarak elde edilen sonuçlar sunulmuştur.

  AtıfOpenAlex2·TR Dizin2

  İncele