Ismail Toroz

Ozonation of Aqueous Solution of Alpha Endosulfan

Ozonation of alpha endosulfan and the effects of some parameters such as pH, temperature and partial pressure on ozonation were investigated and the kinetic constants were calculated in this study. Alpha endosulfan solutions were ozonated in a lab‐scale semi‐batch reactor under variable experimental conditions. Increase in dissolved ozone concentration had a positive effect on oxidation rate. Alpha endosulfan could be removed up to 94% at pH 4 for an ozonation time of 60 minutes. The oxidation reaction was found to be of second order and of first order with respect to both ozone and alpha endosulfan. The temperature dependent reaction expression of alpha endosulfan was obtained as kd = 0.889 exp(− 2.21 × 10− 3/T). It was concluded that, although the rate of reaction was lower than the rate of other pesticide oxidation reported in the literature, alpha endosulfan presented an obvious reaction to ozonation.

Assessment of trihalomethane formation in chlorinated raw waters with differential UV spectroscopy approach.

In this study, the changes in UV absorbance of water samples were characterized using defined differential UV spectroscopy (DUV), a novel spectroscopic technique. Chlorination experiments were conducted with water samples from Terkos Lake (TL) and Büyükçekmece Lake (BL) (Istanbul, Turkey). The maximum loss of UV absorbance for chlorinated TL and BL raw water samples was observed at a wavelength of 272 nm. Interestingly, differential absorbance at 272 nm (ΔUV272) was shown to be a good indicator of UV absorbing chromophores and the formation of trihalomethanes (THMs) resulting from chlorination. Furthermore, differential spectra of chlorinated TL waters were similar for given chlorination conditions, peaking at 272 nm. The correlations between THMs and ΔUV272 were quantified by linear equations with R 2 values >0.96. The concentration of THMs formed when natural organic matter is chlorinated increases with increasing time and pH levels. Among all THMs, CHCl3 was the dominant species forming as a result of the chlorination of TL and BL raw water samples. The highest chloroform (CHCl3), dichlorobromomethane (CHCl2Br), and dibromochloromethane (CHBr2Cl) concentration were released per unit loss of absorbance at 272 nm at pH 9 with a maximum reaction time of 168 hours and Cl2/dissolved organic carbon ratio of 3.2.

Stabilization and solidification of electric arc furnace dust originating from steel industry by using low grade MgO

Abstract In this study, solidification/stabilization (S/S) of electric arc furnace dust (EAFD) which is generated during the production of steel from scrap metals and classified as hazardous waste were investigated by using different ratios of cement and low grade MgO (LG MgO) as binding agents. Type I PC 42.5 R portland cement and LG MgO which contains 70–80% MgO were used. S/S blocks that contain different ratios of binding agents which have 1/0.5 – 1/1 – 1/2 – 1/3 – 1/4 – 1/5 cement/LG MgO ratio and S/S blocks which contain only cement and no LG MgO agents were prepared. These blocks, which contain 3 different waste ratios according to weight, 20%, 30% and 40% respectively, were produced and exposed to 28-day water purification. At the end of the purification process, S/S blocks were extracted using TCLP (Toxicity Characteristic Leaching Procedure) tests in order to determine the leaching behavior of Zn, Pb, and Cd in S/S blocks. By the end of this study, it was concluded that the recovery of EAFD is possible and applicable by immobilization. The findings of the study concluded that environmental performances or structural properties of blocks contain 30% waste by weight are suitable. This method is a proper one for recovering and treatment of EAFD with mixture of cement and LG MgO.

Membrane integrated process for advanced treatment of high strength Opium Alkaloid wastewaters

In this study, an integrated aerobic membrane bioreactor (MBR)-nanofiltration (NF) system has been applied for advanced treatment of Opium processing wastewaters to comply with strict discharge limits. Aerobic MBR treatment was successfully applied to high strength industrial wastewater. In aerobic MBR treatment, a non-fouling unique slot aeration system was designed using computational fluid dynamics techniques. The MBR was used to separate treated effluent from dispersed and non-settleable biomass. Respirometric modeling using MBR sludge indicated that the biomass exhibited similar kinetic parameters to that of municipal activated sludge systems. Aerobic MBR/NF treatment reduced chemical oxygen demand (COD) from 32,000 down to 2,500 and 130 mg/L, respectively. The MBR system provided complete removal of total inorganic nitrogen; however, nearly 50 mgN/L organic nitrogen remained in the permeate. Post NF treatment after MBR permeate reduced nitrogen below 20 mgN/L, providing nearly total color removal. In addition, a 90% removal in the conductivity parameter was reached with an integrated MBR/NF system. Finally, post NF application to MBR permeate was found not to be practical at higher pH due to low flux (3-4 L/m2/hour) with low recovery rates (30-40%). As the permeate pH lowered to 5.5, 75% of NF recovery was achieved at a flux of 15 L/m2/hour.

KUYUM ATÖLYELERİNDE KULLANILAN ATIKGAZ YIKAMA EKİPMANLARININ VERİMLİLİKLERİNİN BELİRLENMESİ

Kuyum atolyelerinde asit ve siyanur kullanilan islemler esnasinda, insan ve cevre sagligi ile malzeme uzerinde zararli olacak nitelikte atik gazlar ortaya cikmaktadir. Olusan bu atik gaz akimlarinin, olustugu atolye icinde uygun yontem ve ekipmanlarla kontrol edilmesi ve zararsiz hale getirilmesi gerekmektedir. Bu amacla cesitli ureticiler tarafindan kuyum atolyelerinde kullanilabilecek atik gaz yikama ekipmanlari uretilmektedir. Yapilan calismada bu amacla uretilmis bir sistemin atik gaz akimi icerisindeki zararli emisyonlari giderme verimi incelenmis ve verimin surekliliginin saglanmasi icin alinmasi gereken onlemler belirtilmistir. Elde edilen sonuclar incelendiginde; kullanilan atik gaz yikama sistemi sayesinde demir/bakir indirme isleminden kaynaklanan nitrik asit emisyonlarinin %94,5, sulfurik asit emisyonlarinin ise %88,3 oraninda giderildigi belirlenmistir. Patlatma isleminden kaynaklanan atik gazlarin yikama sisteminde yikanmasi ile siyanur emisyonun ise %98,7 oraninda giderildigi tespit edilmistir. Elde edilen sonuclara gore aritilmis toksik gaz emisyonlari; Sanayi Kaynakli Hava Kirliliginin Kontrolu Yonetmeligi ve Hollanda Hava Emisyon Klavuzu’nda verilen limit degerlerin altinda kalmistir.

Use of theoretical waste inventories in planning and monitoring of hazardous waste management systems

Hazardous waste (HW) generation information is an absolute necessity for ensuring the proper planning, implementation, and monitoring of any waste management system. Unfortunately, environmental agencies in developing countries face difficulties in gathering data directly from the creators of such wastes. It is possible, however, to construct theoretical HW inventories using the waste generation factors (WGFs). The objective of this study was to develop a complete nationwide HW inventory of Turkey that relies on nation-specific WGFs to support management activities of the Turkish Ministry of Environment and Urbanization (MoEU). Inventory studies relied on WGFs from: (a) the literature and (b) field studies and analysis of waste declarations reflecting country-specific industrial practices. Moreover, new tools were introduced to the monitoring infrastructure of MoEU to obtain a comprehensive waste generation data set. Through field studies and a consideration of country specific conditions, it was possible to more thoroughly elucidate HW generation trends in Turkey, a method that was deemed superior to other alternatives. Declaration and literature based WGFs also proved most helpful in supplementing field observations that could not always be conducted. It was determined that these theoretical inventories could become valuable assets in supporting regulating agencies in developing countries for a more thorough implementation of HW management systems.

Cost Effective Treatment of Textile Mill Effluents by Water Reuse

The treatment results of a full scale plant treating the effluents from an integrated woolen textile industry have been presented. Effluents from the wool finishing process were recirculated after chemical treatment followed by rapid sand filtration. This practice provides a reduction of about one million US Dollars per year in the treatment cost, which corresponds to a pay back period of one year for the whole investment. Lanolin, which is recovered from the acid-cracking sludges, is a valuable by-product resulting in an extra reduction in the treatment cost.