بررسي كارايي لاينرهاي رسي متراكم شده در حذف طبيعي آلاينده هاي شيرابه توليدي در محل دفن زباله هاي شهري (مطالعه موردي: محل دفن كهريزك)

Investigation of compacted clayey liner proficiency for natural removal of generated leachate pollutants in municipal solid waste landfill; Case study: Kahrizak landfill

Use of natural attenuation landfill (NAL) is one of the methods for landfilling of municipal waste that principal concept of its designing is based on natural leachate permeability in soil and it is expected that leachate is treated naturally by unsaturated soil which is located under landfill . Nowadays, using of compacted clayey liners can be count as one investigable choice for natural removal of leachate pollutants because it has less cost in comparison with other liners and also in most parts of Iran (especially in Kahrizak region), proper material are available. Hence, compacted clayey liner proficiency for removal of important leachate pollutants was examined in laboratory scale by using of Kahrizak landfill soil and in touch with this site leachate. For the purpose of more similarity between laboratory model and real condition, new leachate was located on compacted clayey soil every day (52 days) until the time that the soil naturally was saturated and as well as sample permeability was determined, concentration of exit leachate pollutants from saturated soil was measured. Carried out investigation about clayey liner ability for natura! removal of important and worrisome pollutants of Kahrizak landfill leachate shows that although this kind of liner ability for removing phosphate and to some extent sulfate , but other pollutants like COD, BOD, nitrate, bicarbonate and chloride either omitted very lowly or never removed