SDG 12 · Sorumlu Üretim ve Tüketim · SDG · Erzincan Binali Yıldırım Üniversitesi

Yazarlar

Yayınlar

Yeniden eskiye Eskiden yeniye

ArticleAçık Erişim2005/r/ebyu/17633
Removal of phenolic and lignin compounds from bleached kraft mill effluent by fly ash and sepiolite
Ugurlu, Mehmet; Gurses, Ahmet; Yalcin, Mehmet; Dogar, Cetin
This study aimed to remove phenolic and lignin compounds from paper mill industry (4500 m3/h) wastewaters, which is discharged to sea from a plant located in the western Turkey. As adsorbent, fly ash, raw sepiolite and heat-activated sepiolite were used. The effect of factors such as, particle size, temperature and pH on adsorption process was investigated. From kinetic studies, equilibrium time was found as 1 h for both. The kinetic data supports pseudo-second order model but shows very poor fit for pseudo-first order model. Intraparticle model also shows that there are two separate stages in sorption process, namely, external diffusion and pore diffusion. Adsorption isotherms for fly ash and activated sepiolite were obtained at two different temperatures. From experiments carried out at different pHs, it was observed that pH plays an important role in the adsorption process in removing of both lignin and phenolic compounds, providing both ionizating the compounds and modifying sorbent surfaces. It was also observed that heat-activated sepiolite is more effective than raw sepiolite and fly ash to remove these compounds. Adsorption of lignin and phenolic compounds increases with decreasing particle size. In addition, the efficiency of adsorption decreases with increasing adsorption temperature for both fly ash and untreated sepiolite.
RDL Kalıcı Kaydıİncele
ArticleYalnız künye2003/r/ebyu/18246
Investigation of agglomeration rates of two Turkish lignites
Gürses, A; Doymus, K; Dogar, Ç; Yalçin, M
Oil agglomeration is an effective technique for recovering and reducing the ash of coal fines. In this study, the effects of some parameters that markedly influence the effectiveness of selective oil agglomeration, such as solids concentration, amount of agglomeration oil and agglomeration time, on the recovery of agglomerate and the ash and the pyritic sulphur content of the agglomerates were investigated. In order to delineate the relation between the formation rate of coal-oil agglomerates and the removal of ash and pyritic sulphur, the rates of agglomeration for Balkaya and Askale lignites were also calculated by using experimental data. It was found that the success of the process in terms of both recovery and selectivity for lignites was highly dependent on the parameters and control of the agglomeration rate. (C) 2002 Elsevier Science Ltd. All rights reserved.
RDL Kalıcı Kaydıİncele
ArticleYalnız künye2003/r/ebyu/17670
Decolorization and Sedimentation of a Textile Dye by Dissolution of Metallic Aluminum: A Statistical Investigation
Gürses, Ahmet; Yalcin, Mehmet; Dogar, Çetin; Doymus, Kemal
In this study, the decolorization and sedimentation of strong colored solutions containing a reactive textile dye, Remazol Red RB, were investigated. Aluminum hydroxides from dissolution of metallic aluminum were used as flocculant. Experiments were performed according to "24 full factorial experimental design." By using MINITAB software, analysis of variance was carried out. The parameters investigated were aluminum dissolution temperature, initial pH, aluminum dissolution time, and effect of surfactant. Aluminum dissolution temperature and dissolution pH were found to be statistically significant parameters in the decolorization process. From the variance analysis of settling rate, the amount of dissolved aluminum and the mean distribution of floc size, it was found that pH was a significant parameter common in all of these processes. These results suggest that decolorization by flocculation with direct dissolution of metallic aluminum may be practically used for the removal of reactive dyes from aqueous solutions.
RDL Kalıcı Kaydıİncele
ArticleYalnız künye2003/r/ebyu/17630
Removal of Remazol red RB by using AI (III) as coagulant-flocculant: Effect of some variables on settling velocity
Gürses, Ahmet; Yalçin, Mehmet; Dogar, Cetin
This study addresses the research of the removal of a textile dye from aqueous solutions by using aluminum ions as coagulant-flocculant. A simulated textile wastewater was prepared from Remazol Red RB textile dye. The purpose of this study was to investigate the effects of temperature, pH, and concentrations of the cationic surfactant and electrolyte concentration on the settling velocity of the simulated textile wastewater. While investigating these factors, levels of variables were determined by considering the characteristics of traditional textile wastewater like pH, temperature, and dye concentration. Although traditional coagulation-flocculation processes make use of different aluminium salts as coagulant-flocculent, in this study, Al ions dissolved in pH and temperature of traditional textile wastewater were used. Furthermore, sludge volume index values (SVI) were determined and conductivity measurements carried out. The results showed that, in the working range of these variables, the spectroscopic color measurement revealed 100% decolorization yield of wastewater. In conclusion, researchers found that the optimum settling velocity conditions were as follows: low temperature (273K), surfactant concentration of 0.10 g L-1, electrolyte concentration of 0.10 g L-1, dye concentration of 0.025 g L-1 and a pH of 10.05. Finally, by conducting experiments twice under the obtained optimum values, mean settling velocity was 0.014 m min-1 and the mean sludge volume index 140 mL g-1.
RDL Kalıcı Kaydıİncele