Characterization and Flocculation Treatment of Organic Substances Present in Landfill Leachate

Organic pollutants present in landfill leachate are characterized and treated with a novel inorganic polymer flocculants, poly-ferric(III)-magnesium(II)-aluminum(III)-sulfate (PFMAS). First, the removals of COD, BOD₅ and color are determined with optimum conditions by jar-test. Then, organic contaminants in the leachate before and after treatment are identified by gas chromatography coupled with mass spectrometry (GC-MS). The results indicate that the removals of color, COD, and BOD₅ by coagulation with PFAMS can reach 89%, 68%, and 58%, respectively, which greatly reduces the extent of pollution and improves its appearance. About 85 kinds of organic species are identified in the leachate and some of them belong to the Black List of environmental preferred controlled pollutants considered by the USA and China Environmental Protection Agengcy. Particularly, the typical pollutants are quantitatively analyzed. The alkyl, alkene, ester, ketone, aldehyde, acyclic acid, acyclic alcohol and acyclic amine species are removed greatly (about 60-100%), and some are removed completely, while species with a benzene ring, such as aromatic acids, aromatic alcohols, aromatic amine aromatic hydrocarbons, hydroxybenzenes, and pyridines, are partially removed (about 25-70%).