建設汚泥の連続脱水・固化処理システムによる再資源化

Abstract

建設工事に伴い発生する汚泥の処理が環境問題の一つに挙げられており、再資源化を行うためのより効率的な処理方法の確立が求められている。本研究では、建設汚泥の脱水処理、固化処理のそれぞれに関して、汚泥の特性に基づいて処理方法の効果と処理土の特性を検討、整理する。さらにその結果を踏まえて、連続脱水・固化処理システムの構築を目的として、処理効率の評価と検討を行う。

Recently, utilization of the waste sludge from construction sites is strongly required, because a large amount of the sludge with high watercontent is produced, most of the sludge are merely disposed of as waste in the landfill site and some of them are even illegally dumped. Two major present methods are generally applied for the sludge treatment, namely dehydration and solidification, however these methods possess technical and economical limitations. In this paper we propose the continuous dehydration‐solidification treatment system as effective treatment method to utilize the sludge materials. Dehydration characteristics of the sludge are experimentally evaluated, and the effect of the flocculants is examined. As the dehydration level can be expressed in relation to w/wL. (the dehydrated water content normalized by the liquid limit) regardless of other properties of the sludge, solidified properties of the sludge stabilized by cement after dehydration treatment are experimentally assessed and normalized by the index of w/wL.According to these experimental results, we examine the efficiency of this system by using two indexes. In conclusion, the application of the sludge treated by the proposed method as earthen materials is reviewed in relation to the treatment level.