Abstract: The invention provides compositions and methods for controlling setting of carbonatable calcium silicate compositions that are contaminated with hydrating materials. These carbonatable calcium silicate cements are suitable for use as non-hydraulic cement that hardens by a carbonation process and may be applied in a variety of concrete components in the infrastructure, construction, pavement and landscaping industries.

Abstract: An aerated composite material produced from carbonatable calcium silicate compositions (carbonation cured AAC) that has a compressive strength equivalent to autoclaved aerated concrete (ordinary AAC) at substantially the same density and a process of production of the same are provided. The composite material of the present invention comprises: a plurality of bonding elements, each including a core comprising calcium silicate, a first layer which partially or fully surrounds the core and is rich in SiO2, and a second layer which partially or fully surrounds the first layer and is rich in CaCO3; a plurality of filler particles having their particle sizes ranging from 0.1 ?m to 1000 ?m; and a plurality of voids; wherein the plurality of bonding elements and plurality of filler particles together form a bonding matrix and are substantially evenly dispersed in the matrix and bonded together, the plurality of voids are bubble-shaped and/or interconnected channels, a pore volume with a radius of 0.004 ?m to 10.

Abstract: The invention provides a curing system that is useful for curing materials that consume carbon dioxide as a reagent. The system has a curing chamber that contains the material to be cured and a gas that contains carbon dioxide. The system includes apparatus that can deliver carbon dioxide to displace ambient air upon loading the system, that can provide carbon dioxide as it is needed and as it is consumed, that can control carbon dioxide concentration, temperature and humidity in the curing chamber during the curing cycle and that can record and display to a user the variables that occur during the curing process. A method of curing a material which requires CO2 as a curing reagent is also described.

Abstract: Synthetic pozzolans are produced using local materials to provide a cementitious material that is uniform in chemistry and properties independent of the location where the materials are obtained. Two methods of production are described. One is a high temperature process in which materials are processed in a semi-molten or molten state. The second process is a low temperature aqueous process.