Energy and CO2 emission evaluation of concrete waste

Abstract

A significant amount of solid wastes produced every year from construction and demolition activities, and had caused significant pollution to the environment and risen public concern. Therefore, the minimization of construction wastes has become a critical issue in construction industry Concrete is the most commonly used construction material in the world, and after water is the second most consumed product on the planet. The huge popularity of concrete also carries environmental costs, the most harmful of which is the high energy consumption and CO2 release during the production. This paper investigates the amount of energy used and CO2 emission generated during the production of concrete. Furthermore to estimate the total impact of both indicators based on concrete wasted generated on site. Data were obtained through questionnaire survey and interview within the building construction projects in U.T.M. These impact assessment were followed the life cycle assessment (LCA) methodology. The results show that the production of the raw material and the transports of the concrete are the main contributor to the total environmental load . The highest impact value was generated during the production of cement at upstream level .the amount of energy used and CO2 emission by cement production was about 70 percent of the total embodied energy and 95% of the carbon dioxide emissions of concrete production and Within the transportation operations, the transportation of concrete is the largest contributor equal to 25% to 28% the production of concrete and on the other hand 12% to 14% for CO2 emission.