Coke dust enhances coke plant wastewater treatment Piotr Burmistrz a,⇑ , Andrzej Rozwadowski a , Michał Burmistrz b , Aleksander Karcz a a AGH University of Science and Technology, Faculty of Energy & Fuels, Mickiewicz Avenue 30, 30-059 Krakow, Poland b Microbiology Department, Faculty of Biochemistry Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland highlights  We researched industrial adsorptive coke plant wastewater treatment.  Two types of coke dust were examined in three scenarios each.  COD, TOC, 16 PAHs, phenols, cyanide, thiocyanates, ammonium, nitrogen were analyzed.  Coke dust addition enhanced many steps of coke plant wastewater treatment.  The enhanced biological treatment proved the most effective. article info Article history: Received 5 January 2014 Received in revised form 1 July 2014 Accepted 2 July 2014 Handling Editor: O. Hao Keywords: Coke plant wastewater Coke dust Adsorption Biodegradation Coagulation Wastewater treatment abstract Coke plant wastewater contain many toxic pollutants. Despite physico-chemical and biological treatment this specific type of wastewater has a significant impact on environment and human health. This article presents results of research on industrial adsorptive coke plant wastewater treatment. As a sorbent the coke dust, dozen times less expensive than pulverized activated carbon, was used. Treatment was con- ducted in three scenarios: adsorptive after full treatment with coke dust at 15 g L 1 , biological treatment enhanced with coke dust at 0.3–0.5 g L 1 and addition of coke dust at 0.3 g L 1 prior to the biological treatment. The enhanced biological treatment proved the most effective. It allowed additional removal of 147–178 mg COD kg 1 of coke dust. Ó 2014 Elsevier Ltd. All rights reserved. 1. Introduction A large quantity of wastewater is generated during coke pro- duction. Many processes are involved in production. These include: pyrolysis of a coal mixture in a coking chamber, and cooling and treatment of volatile products of coal pyrolysis. They are responsi- ble for generation of by-products. Thus, the wastewater contains among others: ammonia, cyanides, thiocyanates, phenols and other organic compounds, such as PAHs (Ghose, 2002; Ning et al., 2005; Dameng et al., 2011; Burmistrz and Burmistrz, 2013; Zhang et al., 2013). Coke plant wastewater is characterized by low concentration of heavy metals and phosphorus. Concentration of main pollutants in coke plan wastewater depend on many factors (Ghose, 2002; Vazquez et al., 2007). Conventional coke plant wastewater treatment utilize physico- chemical and biological methods. Among the proven biological treatment methods of coke plant wastewater, activated sludge pro- cesses is commonly used (Lee et al., 2002; Woo et al., 2009). In many countries, including Poland, preferred system is based on a single-sludge process with recycle of nitrified effluent, i.e. pre- denitrification process (Li et al., 2003; Kim et al., 2007). Despite complex treatment coke plant wastewater can have adverse impact on ecosystem and human health (Zhang et al., 2012; Zhang et al., 2013). Increase of efficiency of coke plant wastewater treatment is possible by application of adsorption methods. Many research con- firmed removal of phenols (Ahmaruzzaman and Sharma, 2005; Vazquez et al., 2007; Mohanty et al., 2008; Spiridon et al., 2013), cyanide (Zhang et al., 2010a,b), PAHs and other organic compounds (Zhang et al., 2010a,b; Zhang et al., 2012; Ali et al., 2013; Zhang et al., 2013) from industrial wastewaters after utilization of organic sorbents. http://dx.doi.org/10.1016/j.chemosphere.2014.07.025 0045-6535/Ó 2014 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail address: burmistr@agh.edu.pl (P. Burmistrz). Chemosphere 117 (2014) 278–284 Contents lists available at ScienceDirect Chemosphere journal homepage: www.elsevier.com/locate/chemosphere