Environmental concrete now and in the future
Abstract
This thesis investigates the emission profiles of two types of low carbon concrete: Schwenk’s lowheat cement and a geopolymer cement in development from Saferock. As a basis for comparisona case scenario where a low carbon building is being built in Bergen is used. The emissioncalculations are based on Environmental Product Declarations (EPD’s) published by EPD Norgefor each material required in the concrete.The majority of emissions from concrete production is from clinker production, which can bereduced by substituting parts of the binderwith SupplementaryCementitiousMaterials (SCM’s).SCM’s are zero-emission byproducts and they are commonly used in cement production to reduceemissions. Saferock uses instead mining waste as a binder to significantly reduce emissionscompared to traditional concrete types. Industries such as coal-burning power plantsand iron production generate carbon-neutral byproducts used in concrete, thus reducing thecement requirement and lowering associated emissions. This offers an efficient wastemanagementsolution, although it may need to change if SCM’s are not classified as carbon neutral inthe future.The study also considers the potential of using natural SCM’s from Iceland which originatesfrom volcanic eruptions as a sustainable solution. Carbon capture methods are being integratedinto the cement industry, despite their high energy demands. These technologies areonly beneficial when the total emissions captured are less than those produced from increasedenergy production. Such solutions are viable in regions like Norway where hydropower is themain energy source. The introduction of carbon taxes by the European Union (EU) to promotecarbon reduction measures is also explored, along with the conversion of captured CO2 intoSustainable Aviation Fuels (SAF). Different CO2 storage solutions such as Carbfix in Iceland andEquinor’s depleted oil and gas fields in Norway are investigated.The results show that when comparing CO2 emissions from Saferock’s geopolymer concreteand Schwenk’s low heat concrete, Saferock’s concrete reduces emissions by 65.23% (excludingtransportation and reinforcement) and by 43.65% when these factors are included. This marksgeopolymer cement fromSaferock as a superior choice in terms of CO2 emissions for lowcarbonconstruction.