While it is true that fly ash contains trace amounts of certain elements, which can be toxic in larger concentrations, it is unlikely that fly ash as used in concrete would exhibit leaching characteristics. First, the permeability of concrete containing fly ash is negligible compared to the permeability of fly ash as typically disposed. This reduced permeability prevents water or other liquids ...

Two series, each consisting of seven high-volume fly ash concrete mixtures with conductive carbon fibers, were used in this investigation. The first series of the concrete mixtures contained ASTM Class C fly ash and 0, 1, 3, 5, 7.5, 10, and 20 lbs. carbon fibers per cubic yard of concrete. The second series of concrete mixtures contained high-carbon fly ash in addition to the materials used in ...

This paper investigates the effect of fineness of fly ash on the performance of cement mortar. Fly ash from thermal plant is used as partial substitute for cement. Fly ash is used as received and also processed by grinding. The study involves four replacement levels of fly ash into cement at 10%, 20%, 30% and 40% for each mix design. Mortar cubes are tested for strength, water absorption and so...

The leaching characteristics of fly ash from a cobalt smelter were studied as a function of pH and time using the pH-static leaching test (CEN/TS 14997, pH range 5-12) coupled with mineralogical investigation and speciation-solubility modelling. Two sets of experiments with different equilibration time (48 h and 168 h) were performed. The leaching of metals showed typical U-shaped curves with t...

Introduction Fly ash, a by-product from power plants, is a powdery gray material that is stored in large ash dykes or ponds. This ash is used in making bricks and in cement factories. Fly ash is considered to be a major pollution problem as it is dispersed into the air and pollutes bodies of water. However, for the local tribal populations of Korba district, Chhattisgarh state, fly ash is becom...

The potential problems and their consequences due to fly ash disposal have been well studied around the world. Ash pond is a common available disposal facility for thermal power plants. The pond ash is subjected to weathering and the ions present in ash migrate to the soil and subsequently to the ground water over a period of time. A study has been carried out at Vijayawada Thermal Power Statio...

A new iron-fly ash packing was studied for reductive transformation of p-nitrotoluene. The packing was made of iron, fly ash and kaolin with the mass ratio of 36:7:2. A reactor was designed to investigate the long-term performance of the packing. The results showed that the reduction of p-nitrotoluene increased with decreasing pH, because the reduction potential of reaction increased with the c...

OBJECTIVE To assess the health of community residents following a coal fly ash spill at the Tennessee Valley Authority Kingston Fossil Plant in Harriman, Tennessee, on December 22, 2008. METHODS A uniform health assessment was developed by epidemiologists at Oak Ridge Associated Universities and medical toxicologists at Vanderbilt University Medical Center. Residents who believed that their h...

The fly ash is a waste produced mostly from the burning of coal in thermal power station which contributes to environmental pollution. It is naturally-cementitious coal combustion by-product. Many studies have been reported in the literature on the performance evaluation of soil – fly ash system as well soil-fly ashfiber system. Although ample studies have been reported with randomly distribute...