Glossary

 
 
 

A

Absolute/specific CO2 emissions

Absolute CO2 emissions are the total volume of CO2 emitted, while specific emissions are relative and proportionate to a given amount of production. A specific quantity of CO2 is emitted for every 1 ton of cement, for example.

Aggregates

Aggregates are small rock fragments (0.08 to 80 mm) of mineral origin. Aggregates come in different types: maritime, fluvial and terrestrial. They may be sand, gravel or crushed gravel. Aggregates, mixed with water and cement, are essential for the production of concrete.

Aggregates

Aggregates are small rock fragments (0.08 to 80 mm) of mineral origin. Aggregates come in different types: maritime, fluvial and terrestrial. They may be sand, gravel or crushed gravel. Aggregates, mixed with water and cement, are essential for the production of concrete.

B

Bauxite

Bauxite is an aluminum ore. It is named after the village of Baux-de-Provence, France, where it was discovered.

Biodiversity

Biodiversity refers to the diversity of living organisms and species in land, marine and aquatic ecosystems.

Biomass

Biomass refers to any organic material derived from plants that can be used to provide energy. It is the biodegradable portion of:

  • by-products, waste and residues from agriculture, forestry and associated industries,
  • industrial plant waste and residues.

C

C02

Carbon dioxide (CO2) is a greenhouse gas. It is produced by the combustion of organic compounds and the respiratory systems of animals and plants.

The cement industry naturally emits CO2:

  • 60% of emissions are due to the physical-chemical transformation of raw materials at high temperatures,
  • 40% result from the combustion needed to heat the cement furnace to 1500°C.
CO2

Carbon dioxide (CO2) is a greenhouse gas. It is produced by the combustion of organic compounds and the respiratory systems of animals and plants.

The cement industry naturally emits CO2:

  • 60% of emissions are due to the physical-chemical transformation of raw materials at high temperatures,
  • 40% result from the combustion needed to heat the cement furnace to 1500°C.
CO2 quotas

Greenhouse gas emissions quotas and the emissions quotas trading system (EU-ETS scheme) were established by a European directive in 2003.
Revised in December 2008, the directive aims to clarify the conditions for implementation of its target to reduce CO2 emissions in EU (European Union) countries by 20% between 1990 and 2020. The new directive therefore regulates CO2 emissions in EU countries for various industrial sectors (the cement, steel and paper industries, for example).
This mechanism, which applies for the 2013-2020 period:

  • determines annually a quantified limit on emissions for each company (1 quota = 1 ton of CO2),
  • defines selection criteria for sectors most at risk of "carbon leakage" as a result of inflated costs in relation to CO2, which could see their competitiveness adversely affected by countries outside the EU which have not made comparable commitments,
  • grants companies with a surplus of quotas the ability to sell emissions rights to companies with a shortage of quotas.
Cement

Cement is a hydraulic bonding agent which is obtained by heating, then grinding, a mixture of limestone and clay. Most cements are made from clinker and additives and are usually used in the form of a powder. Cement sets when mixed with water. Combined with sand and aggregates (sand or gravel), it turns into rock-hard concrete or mortar.

Cementitious

Called "cement additives", these minerals are used in varying proportions during the last phase of the cement production process. The additives make it possible to obtain a range of cements with different properties. They can be:

  • of natural origin, for example limestone or volcanic and sedimentary rock (pozzolanic rock),
  • of industrial origin, for example byproducts of the steel industry (slag from blast furnaces), the microchip industry (silica fume), and coal-fired power plants (fly ash).

The use of cementitious additives reduces CO2 emissions:

  • firstly, because using additives in cement production automatically reduces the proportion of clinker (the decarbonation phase of clinker production releases a lot of CO2),
  • secondly, because it uses industrial waste which would otherwise have been discarded and treated by the local authority.
Clean Development Mechanisms (CDM)

The Kyoto Protocol does not set limitations on CO2 emissions for developing countries but it does encourage the adoption of alternative mechanisms.

Companies which finance CO2 emission reduction projects in developing countries are compensated with carbon credits.

CDMs. are designed to promote the development of better technologies in emerging economies while enabling industrialized countries to earn carbon credits.

Climate change

The term "climate change" refers to meteorological and temperature modifications observed over the course of the last century. It is attributed to an increase in the concentration of greenhouse gases, such as carbon dioxide (CO2) and methane, in the atmosphere. These gases trap solar energy in the atmosphere, warming the land and the oceans.

According to the Intergovernmental Panel on Climate Change (I.P.C.C), 90% of the increase in the concentration of these gases is due to human activities and only 10% is due to natural causes.

Clinker

Clinker is the main ingredient in cement. These hardened granules are obtained by firing a mixture of approximately 80% limestone and 20% clay to a high temperature. Cement is obtained by grinding clinker and, in some cases, supplementing it with additives.

Clinker

Clinker is the main ingredient in cement. These hardened granules are obtained by firing a mixture of approximately 80% limestone and 20% clay to a high temperature. Cement is obtained by grinding clinker and, in some cases, supplementing it with additives.

Co-incineration

Co-incineration uses waste as an alternative fuel. In this way, waste from one industry becomes fuel for another.

Concrete

Concrete is a building material made by mixing water, aggregates and sand with a binding agent (usually cement) and, if necessary, with additives. This mixture is made on building sites and factories.

The characteristics of a concrete can vary greatly depending on the choice of cement and cement-aggregate ratio, the type of aggregate used, the inclusion of additives, etc. The way concretes are used and surface treated can also have an impact on their performance and appearance. So concrete is reconstituted stone and is sometimes referred to as "liquid stone".

Concrete

Concrete is a building material made by mixing water, aggregates and sand with a binding agent (usually cement) and, if necessary, with additives. This mixture is made on building sites and factories.

The characteristics of a concrete can vary greatly depending on the choice of cement and cement-aggregate ratio, the type of aggregate used, the inclusion of additives, etc. The way concretes are used and surface treated can also have an impact on their performance and appearance. So concrete is reconstituted stone and is sometimes referred to as "liquid stone".

Crushed gravel

Crushed gravel is produced by crushing hard rock. These gravel samples measure from 5 to 25 mm.

Crushed gravel is used as an aggregate during concrete manufacture and as a paving base for road surfaces.

D

Ductility

Ductility refers to a material's capacity to be stretched or bent without breaking. A material which does not have this quality is fragile.

E

EU-ETS scheme

Greenhouse gas emissions quotas and the emissions quotas trading system (EU-ETS scheme) were established by a European directive in 2003.
Revised in December 2008, the directive aims to clarify the conditions for implementation of its target to reduce CO2 emissions in EU (European Union) countries by 20% between 1990 and 2020. The new directive therefore regulates CO2 emissions in EU countries for various industrial sectors (the cement, steel and paper industries, for example).
This mechanism, which applies for the 2013-2020 period:

  • determines annually a quantified limit on emissions for each company (1 quota = 1 ton of CO2),
  • defines selection criteria for sectors most at risk of "carbon leakage" as a result of inflated costs in relation to CO2, which could see their competitiveness adversely affected by countries outside the EU which have not made comparable commitments,
  • grants companies with a surplus of quotas the ability to sell emissions rights to companies with a shortage of quotas.

F

Filler

An inert, finely ground mineral material that is included in paints and hydraulic binders (cement) to reduce costs and, in some cases, modify their physical characteristics. In this respect, they are considered to be a cement additive.

Fly ash

Fly ash is hydrophilic and can be used as a cementitious additive. The ash, which is collected from chimney filters in coal-fired power plants, is composed of vitreous silica, alumina, iron oxide and lime.

They can be used as a partial substitute for clinker and thus help to reduce CO2 emissions.

Fly ash

Fly ash is hydrophilic and can be used as a cementitious additive. The ash, which is collected from chimney filters in coal-fired power plants, is composed of vitreous silica, alumina, iron oxide and lime.

They can be used as a partial substitute for clinker and thus help to reduce CO2 emissions.

Foundation

The foundations of structure distribute its weight and ensure its stability. They are made of poured concrete. The design of foundations must allow them to bear the weight of the construction and prevent any vertical or lateral shifting.

G

Geothermal heat pump

A geothermal heat pump takes advantage of the natural warmth of the ground below the frost line to heat spaces above ground, even though thermodynamic principles should result in this warmth being diffused when it comes into contact with cooler elements.

Governance

Governance is the set of rules (both legislative and internal) which determine the way a company conducts its business. Governance is designed to guarantee transparency, oversight and ethics in business.

Gypsum

Gypsum is a construction material made by firing the gypsum mineral in a kiln and then grinding it. It can be used as a paste or as pre-fabricated boards. Mixed with water, it forms a gel that sets within a few minutes and then hardens. It is widely used for interiors: coatings, dry partitions, ceilings and wall linings in the form of tiles or plasterboard. It has several important properties: accoustic and thermal insulation, fire resistance, etc.

H

Hydraulicity

Hydraulicity is the extent to which a material hardens in the presence of water

I

Industrial ecology

Industrial ecology is a new concept in environmental management. The idea is to improve the way environmental factors (energy resources, natural raw materials, etc.) are integrated into business strategies. Industrial ecology takes its inspiration from the cyclical way in which natural ecosystems operate. Just as nature goes through cycles of production, destruction and recycling, industrial waste from certain activities can serve as raw material or fuel for other industries.

Industrial waste

Industrial waste is the residue from production, processing or use. Waste products from other industries are used both as alternative fuels and as substitute materials. Co-incineration enables enterprises to economize fossil fuels and raw materials while serving the community by processing waste in an economical way that reduces CO2 emissions.

Injury frequency rate

The lost-time injury frequency rate is the number of accidents leading to loss of time, by million hours worked.

International Labor Organization (I.L.O.)

The I.L.O. is a United-Nations agency which brings together governments, employers and workers. Its purpose is to promote decent working conditions throughout the world to ensure employees benefit from liberty, equality, safety and dignity. Its actions encourage the creation of decent jobs and the development of social protection and dialogue.

J

Joint

A joint is the filling or sealing of a gap between two construction elements or a continuous rectilinear separation in a construction, designed to absorb differences in the movement or behavior of 2 adjacent elements.

K

Kyoto Protocol

The Kyoto Protocol aims to counter climate change by reducing carbon dioxide emissions. In effect since February 2005, it has been ratified by over 150 countries but has not been ratified by the United States for example.

Under the Protocol, industrialized countries have until 2012 to reduce their CO2 emissions by 5.2% compared to 1990 levels.

L

Lime

Lime is a binding agent obtained from the calcination of limestone. Limes are divided into 2 categories depending on whether they are set by exposure to carbon dioxide (slaked lime) or to water (hydraulic lime).

Slaked lime is mainly used in traditional finishing plasters, pointing mortars and whitewashes. Hydraulic lime contains clay, giving it similar properties to cement and making it suitable for use as an undercoat or render

N

Net/gross emissions of CO2

Net emissions of CO2 are equal to the gross emissions minus emissions related to the burning of waste.

P

Photovoltaic cell

A photovoltaic cell is an electronic component which generates electrical tension (or voltage) when exposed to light and can therefore be used to produce electricity. These cells produce a constant current with an average voltage of 0.5V.

Plasterboard

Plasterboard panels are industrial building components. They are made in factories by locking a thin layer of gypsum and additives between two cardboard sheets to create thin panels. Plasterboard is put in place with screws or adhesive mortar. The panels can also be nailed or screwed to wooden or metal frames to dress interior walls and partitions.

Portland

The name ‘Portland' comes from a peninsula in Great Britain.

The gray stone of this area has a composition and appearance similar to that of cement. Portland cement is the generic name of basic, highly-efficient hydraulic cements. They are obtained by grinding clinker, which is made from firing a carefully-composed mixture of limestone, silica, alumina and, in some cases, other products.

Pozzolan

Pozzolan is named after Pozzouli, a region near Naples, Italy, which is rich in volcanic ash.

Natural pozzolan is a light siliceous mineral produced during basaltic volcanic eruptions. It contains silica, alumina and iron oxide (which gives it a red color), as well as lime and magnesium oxide. Pozzolan is used as a cement additive.

Artificial pozzolans with the same properties as natural pozzolans can be created by heating clays, basalts or schists.

Pozzolan

Pozzolan is named after Pozzouli, a region near Naples, Italy, which is rich in volcanic ash.

Natural pozzolan is a light siliceous mineral produced during basaltic volcanic eruptions. It contains silica, alumina and iron oxide (which gives it a red color), as well as lime and magnesium oxide. Pozzolan is used as a cement additive.

Artificial pozzolans with the same properties as natural pozzolans can be created by heating clays, basalts or schists.

Purchase/sale of CO2 quotas

In the context of the European Union Emission Trading Scheme (EU-ETS scheme), CO2 quotas can be exchanged by companies:

  • by mutual agreement between 2 companies which negotiate the price,
  • or on one of the "carbon exchanges" set up in Europe.

R

Raw mix

Raw mix is made of finely ground rock thinned with water. It is dosed and homogenized before being put into a kiln to make cement

Rehabilitation

In construction, rehabilitation refers to the renovation of a building which is dilapidated or no longer in compliance with safety standards.

Reinforced concrete

Cement concrete is very resistant to compression but it is less resistant to tensile stress and bending. Steel, on the other hand, is very flexible thanks to its high tensile strength.

Reinforced concrete takes advantage of their different properties by combining steel and concrete to produce a material with high compressive and tensile resistance

S

Silica fume

This by-product of the silicon industry results when quartz is heated to high temperatures. Silica fume - dust particles which measure only 0.2 micrometers - is collected by electro-filters for use as a cement admixture

Slag

This mixture of lime, alumina and silica is produced when iron is smelted with coke in blast furnaces in the steel industry. Slag accumulates on top of the molten cast iron. If cooled quickly, its hydraulic properties are close to those of clinker. Slag takes longer to hydrate but it offers greater stability in corrosive conditions. It is, therefore, a suitable additive for cement and concrete so as to reduce CO2 emissions.

Slag

This mixture of lime, alumina and silica is produced when iron is smelted with coke in blast furnaces. Slag accumulates on top of the molten cast iron. If cooled quickly, its hydraulic properties are close to those of clinker. Slag takes longer to hydrate but it offers greater stability in corrosive conditions. It is, therefore, a suitable additive for cement and concrete so as to reduce CO2 emissions.

Sustainable construction

Sustainable construction aims to limit the impact of buildings on the environment while enhancing their quality in terms of aesthetics, sustainability, durability and strength. Sustainable construction techniques apply across the entire lifecycle of a building, from the selection of initial materials to demolition and recycling.

Sustainable construction signifies in particular:

  • the use of recyclable materials to conserve natural resources,
  • the integration of renewable energy sources into a building's design,
  • the optimization of renewable energy sources.
Sustainable construction

Sustainable construction aims to limit the impact of buildings on the environment while enhancing their quality in terms of aesthetics, sustainability, durability and strength. Sustainable construction techniques apply across the entire lifecycle of a building, from the selection of initial materials to demolition and recycling.

Sustainable construction signifies in particular:

  • the use of recyclable materials to conserve natural resources,
  • the integration of renewable energy sources into a building's design,
  • the optimization of renewable energy sources.
Sustainable development

The World Commission on Environment and Development defines sustainable development as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs".

Sustainable development aims to reconcile 3 major stakes:

  • economic performance,
  • the social consequences of a company's actions (with regard to employees, suppliers, customers and the local community),
  • environmental aspects (achieving a balance between a company's activities and the preservation of ecosystems).

T

Thermal inertia

This term designates the capacity of a material to accumulate and store calorific energy which can then be released over a period of time.

U

United Nations Environment Program (UNEP)

The U.N.E.P., created in 1972, is the highest environmental authority of the United Nations. The UNEP works with United Nations agencies, international governmental and nongovernmental organizations, the private sector and civil society. The UNEP has set up the Sustainable Buildings and Construction Initiative (SBCI), which Lafarge directs.