Treatment options for effluents from a solid waste transport station

In this study the wastewaters originating from solid waste transport stations that are established to compress the collected solid wastes from households in order to ease further transportation to final disposal sites (e.g. sanitary landfills) were investigated in terms of characterization and treatability. The results of conventional characterization showed that although the strength of wastewater may be subject to changes depending on the amount of water used for site cleaning, the effluents can be classified as strong wastewaters. Unlike the landfill leachates the mentioned wastewaters did not contain excessive amounts of nitrogen. The soluble COD of the wastewaters accounted for approximately 80% of the total COD, emphasizing the predominance of soluble organic pollutants. To remove soluble organics on the other hand, although both chemical oxidation processes and biological treatment such as aerobic systems; anaerobic technologies or a combination of both anaerobic and aerobic processes can be applied, biotreatment overcomes chemical oxidation due to economic concerns. Assessment of inert COD fractions under aerobic and anaerobic conditions indicated that an anaerobic process must be applied as the first unit of the treatment scheme. However since it was not possible to comply the discharge limitations of 160 mg l–1 COD by solely using an anaerobic biological treatment, an additional treatment unit i.e. aerobic biological treatment or chemical oxidation etc. following the anaerobic one must be used. It was recommended to run additional experimental research to find out more about both the proper type and the optimal operating conditions of the mentioned second treatment unit.