土木与环境工程学报

Using of Wastewater Dry and Wet Sludge In Concrete Mix

Abstract

Ghada Mourtada Rabie

wastewater treatment plants in Egypt, since the amount of sludge produced every year in Egypt are about “4 Million ton “, this amount of sludge is considered a big/dangerous problem which facing Egypt today. Thus, all over the world the researchers are trying to explore a new and suitable way to solve the sludge huge amount which produced from the WWTPs. One track of these solutions is to use sewage sludge in Construction field” concrete mixtures and in manufacturing interlock brick samples’’, evaluated the reuse of sewage sludge from urban wastewater treatment plants in a mixture with cement and to develop new construction materials. According to results findings, no significant strength loss was observed when using the dry or wet sludge with different percentages from the cement weight, in which the strength loss was increased to 63.7% after 7-days and 61.6% after 28-day for dry and for wet 73.4% after 7-days and 68.5% after 28-days when 20% of wet and dry sludge pellets by cement weight was added to concrete mixture. The results showed that the wet sludge retarded the strength development and has more adverse effect on compressive strength than the other dry sludge for the same percentage as the average strength loss after 28-days for wet percentages approximate about 13.76% and for dry sludge approximate about 7.73%. Finally the study concluded that the dry and wet sludge can be used in as an additive to concrete mixtures till 15% form cement weight as one of the available disposal options for Egypt sludge. The study recommended that more researches are needed to evaluate the durability of sludge concrete and the behavior of reinforced sludge concrete.