China
Africa
Explore chapters and articles related to this topic
Development in Materials for Sustainable Manufacturing
Published in R. Ganesh Narayanan, Jay S. Gunasekera, Sustainable Material Forming and Joining, 2019
Eco-cement: A considerable amount of energy is consumed and a large amount of greenhouse gases are emitted while producing Portland cement. One ton of CO2 is produced by 1 ton of Portland cement (Wallah and Rangan, 2006). Eco-cement is manufactured by substituting a part of the raw materials for cement production with municipal wastes. In the eco-cement, approximately 50% of municipal wastes replace the cement raw materials.
Other types of cement
Published in Peter Domone, John Illston, Construction Materials, 2018
The search for uses of industrial waste as an alternative to sending it to landfill has resulted in the development of some potential processes for conversion to cementitious materials. In Japan an ‘Eco-cement’ has been produced in which up to 50% of the raw materials for Portland cement production is substituted by municipal solid waste in the form of incinerator ash and sewage sludge (Shimoda and Yokoyama, 1999). The required clinkering temperature (1350°C) is a little lower than that for Portland cement (1450°C); the resulting cement contains similar compounds to Portland cement albeit with a generally higher C3A content. Its properties are, not surprisingly, claimed to be similar to those of Portland cement. However care has to be taken during the production process to remove and recover chlorides and toxic heavy metals. A rapid-hardening version in which the chlorides are not recovered is also available.
Other types of cement
Published in Marios Soutsos, Peter Domone, Construction Materials, 2017
The search for uses of industrial waste as an alternative to sending it to landfill has resulted in the development of some potential processes for conversion to cementitious materials. In Japan, an ‘eco-cement’ has been produced in which up to 50% of the raw materials for Portland cement production substituted by municipal solid waste in the form of incinerator ash and sewage sludge (Shimoda and Yokoyama, 1999). The required clinkering temperature (1350°C) is a little lower than that for Portland cement (1450°C); the resulting cement contains similar compounds to Portland cement albeit with a generally higher C3A content. Its properties are, not surprisingly, claimed to be similar to those of Portland cement. However, care has to be taken during the production process to remove and recover chlorides and toxic heavy metals. A rapid hardening version in which the chlorides are not recovered is also available.
Enhanced elution of chloride ions from incinerator bottom ash
Published in Chemical Engineering Communications, 2021
Gjergj Dodbiba, Xiang Zhang, Yonggu Kim, Mauricio Córdova Udaeta, Josiane Ponou, Toyohisa Fujita
In Japan, the cement produced by using 500 kg/t or more incinerator bottom ash is known as eco-cement. The production of eco-cement is relatively low (about 6.55 million tonnes per year), i.e., approximately 9.8% of the required amount for cement. Moreover, the recycling ratio of the incinerator bottom ash is 40 to 50%, and about 4.5 million tonnes are being disposed to landfilling sites without being recycled. In order to increase the production of eco-cement, the most important task is, therefore, the removal of chlorine from incinerator bottom ash, since its concentration is relatively high (Hashimoto et al. 2006). A high chlorine concentration can cause serious damage to the reinforced concrete structure. Quraishi et al. (2017) reviewed chloride-induced corrosion of the reinforced steel in concrete and reported the chloride threshold level as the chloride ion concentration. According to Japanese Industrial Standard, the Cl content in eco-cement should be less than 0.1%, whereas in Portland cement should be to less than 0.035%, (Table 1, Tsuji and Suzuki 2002).