Management of hazardous wastes by solidification/stabilization techonology

Abstract

In this study, management of hazardous wastes in sludge form containing some potentially toxic heavy metals and organic chemicals by solidification/stabilization technology was investigated. During experimental studies, the solidification/stabilization technology was applied to the industrial treatment sludge which was originated from a chemical-metal finishing industry. Hazardous wastes were analyzed by using eluat and extract procedures as defined and the hazard characteristics of the waste were determined based on both Turkish and United States Environmental Protection Agency regulations by means of leaching test methods (DIN 38414-S4 Test and Extraction Procedure Toxicity Test). Portland cement was used as a binder for S/S of hazardous waste. Control and other specimens were prepared with dried sludge, cement, fine aggregate, course aggregate, water and a concrete additive as C 35 class of concrete. Compressive strength tests and leach tests were conducted for solidified concrete specimens. Total organic carbon and the heavy metal concentrations in EP extracts and eluats were determined. Main objectives of this study were to implement the S/S technology on the wastewaler treatment system sludge and to investigate compatibility with disposal and recovery. This study indicates the hazard criteria removal of these sludges by S/S technology and leads to solve problems about the management alternatives of these hazardous wastes. It was found out that S/S was an effective technology in treatment and recovery of hazardous wastes.

Özet

Bu çalışmada, solidifikasyon/slabilizasyon teknolojisi kullanılarak zararlı atıkların yönetimi incelenmiştir. Deneysel çalışmalarda, bir kimya-metal son işlemler endüstrisinden çıkan arıtma çamurunun solidifıkasyon/stabilizasyonu için bağlayıcı olarak Portland Çimentosu seçilmiştir. Beton numuneleri hazırlandıktan sonra basınç dayanım ve sızma deneyleri yapılmıştır. Zararlı atığın ve beton numunelerinin sızma özelliklerini belirlemek üzere iki yöntem kullanılmıştır. Bunlardan biri DIN 38 414 S4 Testi diğeri ise Ekstraksiyon Prosedür Toksisite Test Metodudur. Her iki prosedüre göre DIN eluatları ve EP ekstraktları hazırlanmış ve toplam organik karbon ile metal ölçümleri yapılmıştır. Arıtma çamurlarının arıtım ve geri kazanımında, solidifikasyon/stabilizasyon teknolojisinin etkin olduğu sonucuna varılmıştır.