Coal Sludge Permeability Assessment Based on Rowe Cell Consolidation, and Filtration Investigations

Abstract

In this paper, an attempt has been made to investigate the possibility of using coal sludge to seal a landfill site by presenting the results of their compressibility and permeability tests. Coal sludge is a fine-grained waste from the coal enrichment process, and its permeability is also highly dependent on its degree of consolidation. The tests were carried out in a Rowe Cell, making it possible to determine the water permeability coefficient more precisely by determining the degree of the material consolidation during testing. The test was carried out using backpressure conditions. The test procedure in the Rowe Cell consisted of the following three steps: saturation, consolidation, and filtration. The coal sludge was taken directly from the filter presses as a by-product of the fines’ coal enrichment process. The paper presents the results of the individual stages performed in a Rowe Cell. The consolidation coefficient was determined using three different methods (Casagrande, Taylor, and Robbinson methods). The permeability coefficient was measured by the indirect and the direct method, the results of both were compared. The results (k < 10−9 m/s) indicated that the value of the permeability coefficient responds to the value for isolating barrier materials.

Analysis of the properties of coal sludge in the context of the possibility of using it in biological reclamation

“…CS is characterized by a relatively low filtration coefficient in the range of 10 -5 to 10 -10 m/s. This parameter can be further reduced by mechanical concentration or by mixing with other wastes, such as fly ash from coal combustion (Klojzy-Kaczmarczyk and Mazurek 2017; Adamczyk and Pomykała 2022). Therefore, CSs are used to build settling tanks (in which they are deposited) or other hydrotechnical facilities or separation barriers.…”