Alternative fuels and raw materials (AFR):

Waste materials used for co-processing are referred to as alternative fuels and raw materials (AFR) (see Co-processing).


Aggregates for concrete comprise small stones, gravel and sand.

Best practices

A best practice is a method or technique that has been generally accepted as superior to any alternatives because it produces results that are superior to those achieved by other means or because it has become a standard way of doing things, e.g., a standard way of complying with legal or ethical requirements. GCCA is developing best practices documents for its members as to demonstrate industrial leadership in cement manufacturing.


Biodiversity refers to the variety of plants or animals in a particular area. In the cement and concrete sector it is usually used in relation to quarries (see Quarries Rehabilitation).

Built environment

Built environment encompasses all buildings and man-made infrastructure such as rail and road transport; ports and airports; water supply, collection and flood defences; energy generation, storage and distribution. 


By-product is a substance, resulting from a production process, the primary aim of which is not the production of that item. The cement and concrete industries use by-products from other industries such as slag from the steel industry and fly ashes from coal fired power plants.  


Cement recarbonation or concrete carbonation refers to the process where CO2 is absorbed by concrete during its use and end-of-life phase. The amount absorbed is significant but less than the total emitted in cement production (see Recarbonation).

CCUS (Carbon Capture Use and Storage)

Carbon capture, utilization and storage (CCUS), also referred to as carbon capture, utilisation and sequestration, describes processes that capture CO2 emissions from industrial sources and either reuses or stores it so it will not enter the atmosphere. 


Cement is a powdery material which mixed with water, sand and gravel will form concrete and mortar when mixed with water (see Clinker, Concrete).  

Circular economy

The concept of a circular economy has to be seen as a ‘system’, opposed to the traditional linear economy. Circular economy means aiming at minimising waste and making the most of resources. It also means designing for circularity.  

Clean energy

Clean energy is synonym to renewable energy. It refers to energy sources such as wind, hydro, solar, geothermal energy as well as energy from biomass (see Renewable energy).

Climate change

Climate Change is a concept which designate both global warning and its effects (see Global warming). 

Climate mitigation

Climate change mitigation designates the actions to limit the magnitude or rate of long-term global warming and its related effects. It include mitigating emissions and adapting to the consequences of climate change.  


Clinker is a nodular material produced made by heating limestone and clay at a temperature of about 1400 °C – 1500 °C. It is the basic ingredient of cement, the one which confers hydraulic properties to cement. (see Cement, Concrete, Limestone).

Clinker substitutes

Clinker substitutes are alternative materials to clinker in cement production. The use of clinker substitutes is one of the main lever for the reduction of CO2 emissions related to cement manufacturing.  


CO2 stands for carbon dioxyde. It is a colorless, odorless, and non-combustible gas. It is a greenhouse-gas that contributes to global warming. Formed by complete combustion of fossil fuels (coal, charcoal, natural gas, petroleum) and CO2 containing products (such as limestone), it is released also through living organisms respiration and by the gradual oxidation of organic matter in soil. 


Greenhouse gas emissions expressed as an equivalent CO2. For example, methane greenhouse gas potential is many times higher than carbon dioxide, but for simplicity all the equivalent emissions are expressed in terms of CO2. Often it is simply described in shorthand as CO2: it is critical to ensure that the more rigorous CO2e is being reported/compared even if the shorthand is used (see CO2, greenhouse gas).


Concrete is a building material, the most man-made used substance after water. Concrete is made of cement, sand, aggregates, water and admixtures. It is initially malleable in its “wet” state and solidifies over time, gaining strength and durability (see Clinker, Cement, Aggregates, Admixtures).


Is a term that refers to the use of waste as a source of energy or raw material (or both) to replace fossil fuels such as coal, petroleum and gas (energy recovery) and natural mineral resources (material recycling) in industrial processes such as cement production. Waste materials used for Co-processing are referred to as alternative fuels and raw materials (AFR). 


Durability describes how a material resists mechanical or chemical degradation.

Embodied CO2 ( ECO2e)

The CO2e arising from the whole life of a material/project. It is critical that the whole life is considered. It is critical that when comparisons are made between materials and products that there is functional equivalence (for example same service life) and the same rules are applied in determining the embodied CO2 (for example what is and is not included).

Environmental Product Declaration (EPD)

An independently verified and registered document that communicates transparent and comparable information about the life-cycle environmental impact of a product.

Operational CO2

Operational CO2 (or more correctly ‘Operational CO2e’) is the carbon dioxide (or more correctly, all greenhouse gases expressed as equivalent CO2) that are caused by the operation of a building or infrastructure.  


A term commonly used to describe alkali activated binders. Until now, alkali activated binders have been produced mostly for demonstration purposes and have only been used in non structural applications e.g. paving. Up to 90% CO2 emissions reduction compared to Portland cement is postulated but this does not take into account emissions due to the production of the activators. So based on today’s knowledge, the reduction potential of materials like slag or fly ashes as clinker substitute in blended cements seems to be more efficient than the use of alkali activated binders.


“Getting the Numbers Right” (GNR) or “GCCA in Numbers” is a voluntary, independently-managed database of CO2 and energy performance information for the global cement industry. The database delivers uniform, accurate and externally-verified data so that the industry and its stakeholders can understand the current performance  and future potential.  

Greenhouse gas

A greenhouse gas is a gas that absorbs and emits radiant energy within the thermal infrared range (see CO2, CO2e).

Global warming

Global warming is a long-term rise in the average temperature of the earth climate system. Global warming and climate change are often confused but in fact climate change is a broader term as it includes both global warming and its effects such as extreme weather events and changes in precipitation (see Climate change).


Rail and road transport; ports and airports; water supply, collection and flood defences; energy generation storage and distribution (see Built Environment).

Hydraulic properties

The term hydraulic proporties is used to describe a the fact that when mixed with water, cement reacts chemically and becomes hard and strong. Cement is categorized as either hydraulic or nonhydraulic, depending on how it mixes with water. Nonhydraulic cement does not harden underwater or in damp conditions. Certain chemicals are added to make hydraulic cement. 


Innovation is a “new idea, creative thoughts, new imaginations in form of device or method”. GCCA’s mission is to drive, support and advocate innovation in the cement and concrete sector to improve its sustainability and in particular lower its CO2 footprint in particular facilitate research and develop partnership with key stakeholders (including for research, funding and advocacy). 


Limestone is a sedimentary rock mainly composed of calcium carbonate. This is why when heated it releases CO2. It is the main raw material used in clinker production. Limestone is the main raw material used in cement production (see Clinker, CO2).

New binders

New binders or novel cements is a term used to designate alternative to traditional Portland clinker based cements. Those are binding materials manufactured using novel, low-carbon processes that offer similar performance to traditional cement. Most react in a familiar way with water, but some react with CO2 to solidify into a hardened mass (see Clinker, Cement). 

Novel cement see new binders  

Occupational health

Occupational health is the branch of medicine which deals with the prevention and treatment of work-related injuries and illnesses.


A quarry is an open surface where stone, rocks, construction aggregate, sand, gravel, clay limestone is excavated from the ground.  

Raw materials

A raw is a primary basic material, unprocessed, or commodity used in the primary production or manufacturing of good. Cement and concrete industries main raw materials are limestone, clay, sand and aggregates. Those are also sometimes called feedstock. 


Cement recarbonation or concrete carbonation refers to the process where CO2 is absorbed by concrete during its use and end-of-life phase. The amount absorbed is significant but less than the total emitted in cement production (see Carbonation).


Rehabilitation of a quarry is the action of restoring a usable habitat for ecosysten when the quarrying operation is finished. The cement industry would in most case operate rehabilitation by extraction zone.  

Renewable energy

Renewable energy is energy that is produced from renewables sources (naturally replenished on a human scale) such as energy from wind, hydro, solar, geothermal, tide, waves and biomass.


The ability to deal with stress accumulation on a system or a shock event such as natural disaster, accident or malicious attack.


Safety at work describes policies and procedures in place to ensure the safety and health of employees within a workplace. Ensuring healthy and safe working conditions for employees and contractors is the most important priority for the cement and concrete industry and its broader value chain. We are committed to strive to achieve zero harm for employees contractors and everyone that come in contacts with its business. Everyone has a right to go home safe and healthy at the end of every day. 


Sustainability is the concept of meeting the needs of today without compromising the ability of future generation to meet their needs. It is composed of three pillars: economic, environmental and social sometimes informally called triple bottom line and known as profits, planet and people. GCCA is working on concrete triple bottom line. 

Thermal mass

Thermal mass is a material property. It is the ability of a material to absorb, store and release heat energy. It is measured in W/m2/K.  The higher the thermal mass, the larger the energy absorbed/released per unit area per degree Kelvin temperature difference between the internal temperature and the temperature of the material (see Thermal Insulation, Thermal Decrement).

Thermal decrement

Thermal Decrement describes the effect of thermal mass on energy transferred through a wall when the external and internal temperatures are not constant.  When the outdoor temperature cycles above and below the indoor temperature in a 24 hour period the thermal mass enhanced effect means a heavyweight wall can thermally outperform a lightweight wall with the same steady-state thermal insulation value.  

Thermal insulation

Thermal Insulation is measured in W/m2/K. The better the insulation the lower the energy that is transferred across an external wall/roof/floor per unit area per degree Kelvin temperature difference between inside and outside.  If the temperature difference is doubled, so is the energy transferred. Thermal insulation values are based on a steady state temperature difference between inside and outside (see Thermal Decrement).


 The increase in habitation of cities as a percentage of total population.

Value chain

A value chain is used to describe the system which include the full range of activities – including design, production, marketing, distribution and use, linked to a particular business. In the case of cement and concrete, the whole value chain included raw materials quarrying, energy supply, production and use, design, buildings contractors and architects, buildings users and end of life actors. A high-level model developed by Michael Porter used to describe the process by which businesses receive raw materials, add value to the raw materials through various processes to create a finished product, and then sell the finished product to customers. 

Whole life

Whole life (see also cradle-to-grave) describes all stages in a product or project life from material sourcing to end of life prior to second life. It includes sourcing, processing, manufacture, construction, use, maintenance, re-use, demolition and processing for second life as well as transport impacts. In the case of biogenic products it includes release of carbon dioxide or methane arising from combustion or landfill.


A waste is a substance or an object which its owner discards, intends to discard or is obliged to discard. Waste can be re-used, recycled or recovered. This is the concept of a circular economy (see Circular Economy, Alternative Fuels and Raw Materials).

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