A. Kwiecińska, J. Figa, M. Chrubasik, K. Rychlewska
Institute for Chemical Processing of Coal, Zabrze, PL

MAIN CONTAMINANTS IN COKE OVEN WASTEWATER – METHODS OF DETERMINATION AND REMOVAL


Coking of coal is a type of process, which affects all environmental species due to emissions of contaminants to air, soil and water. Coke oven wastewater, which is generated during coke oven gas cooling and cleaning is found to be one of the most contaminated wastewater generated in industry. This wastewater is a mixture of harmful organic, i.e. PAHs and phenols, as well as inorganic, i.e. cyanides, ammonia and sulphides compounds. National, European and international regulations establish sharp standards on permissible concentrations of particular contaminants present ic coke oven wastewater, which have to be fulfilled in case when the stream is deposited to environment. Hence, it is crucial to use technologically effective wastewater treatment processes together with proper analytical methods, dedicated for analysis of contaminants in such a complex matrix. In this paper, the review of unit operations used in currently operated coke oven wastewater treatment plants, dedicated to removal of main coke oven wastewater contaminants, is made together with the evaluation of analytical methods used in their characterization. Finally, a guideline for possible modernization and improvement of coke oven wastewater treatment plants, based on assumptions of zero liquid discharge systems, enabling partial or complete closing of wastewater loops at coke oven plants is presented.

Keywords: coke oven wastewater, contaminants, analysis, treatment