“Carbon dioxide equivalent" or “CO2 equivalent” or "CO2e" means a measure for comparing carbon dioxide with other GHGs, based on the quantity of those gases multiplied by the appropriate global warming potential (GWP) factor and commonly expressed as metric tonnes of carbon dioxide equivalents (MTCO2e).
“Catalyst” means a substance added to a chemical reaction, which facilitates or causes the reaction, and is not consumed by the reaction.
“Catalyst coke” means carbon that is deposited on a catalyst, thus deactivating the catalyst.
“Catalytic cracking” means a refinery process of breaking down larger, heavier, and more complex hydrocarbon molecules into simpler and lighter molecules. Catalytic cracking is accomplished by the use of a catalyst.
“Catalytic reforming” means a refining process using controlled heat and pressure with catalysts to rearrange certain hydrocarbon molecules.
“Cement” means a building material that is produced by heating mixtures of limestone and other minerals or additives at high temperatures in a rotary kiln to form clinker, followed by cooling and grinding with blended additives. Finished cement is a powder used with water, sand and gravel to make concrete and mortar.
“Cementitious product” means cement, cement kiln dust, cement clinker, clinker dust, fly ash, slag, and other pozzolans.
“Cement kiln dust” or “CKD” means the fine-grained, solid, highly alkaline waste removed from cement kiln exhaust gas by air pollution control devices. CKD consists of partly calcined kiln feed material and includes all dust from cement kilns and bypass systems including bottom ash and bypass dust.
“Cement plant” means an industrial structure, installation, plant, or building primarily engaged in manufacturing Portland, natural, masonry, pozzolanic, and other hydraulic cements, and typically identified by NAICS code 327310.
“Clinker” means the mass of fused material produced in a cement kiln from which finished cement is manufactured by milling and grinding.