Glossary


This glossary can help. Offering same of definitions in every area of materials recovery, recycling for agricultural use or waste-to-energy conversion.

• Biogas or landfill gas
A gas created by the process of biological decomposition of organic matter in the absence of oxygen. It has a high methane content (50%), and thus a high calorific value and energy potential. In our businesses, it is produced in landfills, methane production units and wastewater treatment sludge digesters. It has to be collected to eliminate nuisances (odors and contribution to the greenhouse effect). Once collected, it constitutes an alternative source of energy to fossil fuels.

Bioreactor
Bioreactor technology is used to speed up the production of biogas. It involves recovering the leachate and reinjecting it back into the waste mass. As moisture and nutrients are thus provided for the bacteria at work in the mass, bioreactor technology accelerates the decomposition process and so facilitates the recovery of methane that can be used as a source of energy. The combustion of methane has economic and environmental advantages: it reduces the greenhouse effect and is a significant source of energy.

Biodegradable fraction of household waste
See organic waste.

Bottom ash
Bottom ash is the slag or solid residue from waste combustion, recovered from the bottom of a furnace. A distinction is made between the bottom ash from the incineration of household waste and the incineration of hazardous industrial waste. Current regulations classify bottom ash from household waste as recyclable, treatable or storable. Recyclable bottom ash can be used for road construction under certain conditions. Bottom ash from hazardous industrial waste is treated at landfills or recycled under certain conditions

Bulky waste
Waste from household activities that, because of its volume or weight, is not included in the usual collection system, but needs special handling. For the most part, bulky waste is only an occasional occurrence. It includes:
- used household appliances
- debris
- construction and demolition waste
- green household waste.

Cell
A waterproof pit containing sub cells into which waste is deposited in a landfill. A landfill is composed of several cells. Each one is hydraulically independent and designed to facilitate the recovery of biogas and the collection of leachate. A geomembrane liner and draining materials ensure the cells are waterproof. The cells are surrounded by waterproof barriers. The whole landfill is also surrounded by a boundary barrier. The height and slope of the barriers, the distance from cells to the outer limit of the operation, and inspections are all covered by regulations.

Clinker or bottom ash
Bottom ash is the slag or solid residue from waste combustion, recovered from the lower exit of a furnace. A distinction is made the bottom ash from the incineration of household waste, and the incineration of special industrial waste. Current regulations classify bottom ash from household waste as recyclable, treatable or storable. Recyclable bottom ash can be used for road construction under certain conditions. Bottom ash from special industrial waste is treated at landfills or recycled under certain conditions

CO2 emissions
See Greenhouse gases

Cogeneration
This clean technology enables the simultaneous production of electricity and heat from a given type of fuel.

Composting
A biological process that uses air to accelerate the decomposition of organic waste to produce compost. The composting reactions release heat that sterilizes the compost (i.e., eliminates the pathogens in the incoming waste).

Compost
Product produced by composting waste. It can be used as an organic soil improver to improve soil structure, or as a plant fertilizer.

Digestate
The residue or “digested” waste produced by methane production from organic or biodegradable waste. Digestate is made up of excess bacteria, organic matter that has not broken down and mineralized matter. After treatment, it can be used as compost

Dioxins
Generic name for a family of chlorine-containing organic substances that form during combustion processes. Dioxins are produced during the combustion of products containing chlorine (cement, herbicides and pesticides, pulp bleaching, smelting, metal-working, steel-making, incinerating waste, etc.). They can also result from natural sources that are hard to evaluate (e.g., open-air combustion: garden fires, chimneys, ditches, etc.). With regard to incineration, efforts undertaken to protect the environment (closing obsolete plants and introducing new flue gas treatment systems) have already enabled emissions to be reduced by around 70% in this sector. Of the 210 dioxins, 17 are considered toxic.

Effluent
Effluent generally refers to household and municipal wastewater (effluent channeled to treatment plants) and, by extension, wastewater from industrial processes.

Facilities management
The provision of this service involves the management of all general and technical services for an industrial or service site

Fermentable fraction of household waste
See organic waste.

Final waste
Waste, whether treated or not, that cannot be treated any further under existing technically and economically feasible conditions, especially the extraction of the recyclable portion or by reducing its polluting nature

Flare tower
A structure resembling a high chimney used for burning off petroleum byproducts.

Flue gas treatment
During waste incineration, oxidation reactions occur that generate gases. These contain particulate impurities, gaseous combustion residue and gases resulting from thermochemical reactions.
Flue gas treatment consists of purifying the gases before discharging them into the atmosphere.
Treatment consists first of reburning the gases in a postcombustion chamber. Then, once they have cooled down, the gases are cleaned by extracting the various pollutants still present. At this stage, the residual dioxins are, for the most part, removed. To complete the treatment, the gases are filtered.
The recovered treatment residue (water and solids), described as flue gas treatment residue, is treated, stabilized and deposited in a type 1 landfill in compliance with regulations.
The pollutants obtained from incineration are incorporated into hydraulic binders, which permanently fix them physically and chemically in a cement-type matrix.

Furnace
This is the base of the incinerator, which is designed and built according to the volume and type of waste to be treated.

Grab crane, hydraulic crane
A hydraulic crane equipped with four mobile teeth forming a clamshell bucket. Grab cranes are used for demolition and/or handling waste and other materials.

Greenhouse gases
These are gases that absorb part of the sun’s rays, such as, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), tropospheric ozone (O3), CFCs and HCFCs, synthetic gases that attack the ozone layer, as well as CFC substitutes: HFC, PFC and SF6. Onyx’s emissions are mainly CO2 and CH4. The impact of the latter gas on the greenhouse effect is 21 times greater than CO2. Using clean fuel, the energy from landfill biogas and developing cogeneration are all ways of substantially reducing the greenhouse effect.

Greenhouse effect
The atmosphere lets most of the sun’s rays filter through to warm the surface of the earth. The earth re-radiates this energy into space as high wavelength infrared radiation. Water vapor, carbon dioxide and other gases absorb this radiation emitted by the earth, preventing the energy from passing directly from the earth’s surface into space, and so heating up the atmosphere. The increased greenhouse gas content in the atmosphere acts like double-glazing: If the input of the sun’s rays remains constant within the greenhouse, the temperature will rise.

Hazardous waste
Waste generated by industrial activity and healthcare presenting a risk for human health or the environment, and which requires appropriate treatment, such as:
Thermal treatment: combustion at very high temperature (for organic waste) or separation by evaporation (for used fluids or highly aqueous waste);
Mineral or organic physicochemical treatment: one example is stripping, a process that uses gas to drive out volatile compounds;
Biological treatment: the transformation of dissolved organic matter into sludge that can be extracted from the water. This treatment is suitable for biodegradable liquid wastes.
Other treatment processes are sometimes used. These include bioremediation (the use of micro-organisms to break down pollutants) and the stabilization-confinement system (maximum reduction of volume of waste, stabilization and confinement in primary packaging).
The treatment residue of hazardous waste is stabilized before being buried in a type 1 landfill

Household waste flue gas treatment
The residue from the treatment of household waste incineration flue gas is a solid residue collected after chemically treating flue gas to reduce pollution. The treatment is based on neutralization combined with filtration. The target pollutants are acid gases and dust, plus heavy metals, nitrogen oxides and dioxins, which are treated by supplementary processes. The neutralizing reagents can be injected dry in the form of powder (lime or sodium bicarbonate), by semi-wet means (pulverized milk of lime), or by wet means in a soda washing column. These processes generate residual products, mainly comprised of fly ash (dust). Flue gas treatment residue is stabilized before being stored in authorized landfills. These processes are used to treat over 98% of household waste incineration flue gas.[NB: Industrial waste flue gas treatment (REFIDI: Résidus d’Epuration des Fumées d’Incinération de Déchets industriels)

Household and similar waste
Waste generated by retailers, trades people, offices and industry collected at the same time and under the same conditions as household waste.

Household waste
Waste generated by household activity.

Hydrocarbons
Binary carbon and hydrogen composites. Oil and natural gas are hydrocarbons.

Incineration
A thermal waste treatment method involving combustion (the technology and temperature vary depending on the type of waste), and flue gas treatment. This technique yields three types of residue: bottom ash, fly ash and flue gas treatment residue. The heat generated by incineration is recovered at most facilities to produce energy (electricity or heat).

Inert waste
Waste that undergoes no significant physical, chemical or biological transformation. Inert waste does not dissolve, burn or otherwise physically or chemically react. It is not biodegradable and does not adversely affect other matter with which it comes into contact in a way likely to give rise to environmental pollution or harm to health. (Source: European Council Directive 1999/31/CE of April 26, 1999.)

ISO 14 031 Standard
This standard evaluates an organization’s compliant use of management indicators, comparing the past and present environmental performance of the company’s business on the basis of the “plan, do, check, act” process.
OHSAS 18001 Specification
OHSAS 18001 augments and is compatible with ISO 14001. It is designed to assess and certify occupational health and safety management systems.

ISO 14 001
The ISO 14001 standard evaluates the ability of an organization to control the impact on the environment of its activities and to comply with regulations..

ISO 9001
The ISO 9001 standard assesses the capacity of an organization to meet the customer’s requirements with regards to the quality of a product or service.

Landfill
An authorized installation to treat and store waste in optimum safety conditions. In the European Union, there are three classes of landfill: (i) for hazardous waste that has been stabilized or has become inert, (ii) for municipal and similar waste, and (iii) for household waste and non-hazardous industrial waste, i.e. non-hazardous inert waste.

Land application
The even distribution on land of effluent from animal husbandry, soil improvers, fertilizers, crop-care products and wastewater treatment sludge, etc.

Leachate
When stored in landfills, waste generates a liquid called leachate as a result of the combined effect of rainwater and natural decomposition. With a high organic and trace element content, this leachate cannot be discharged directly into the natural environment. It must be carefully collected and treated.

Lipofit
Fatty concentrate produced by the treatment of fatty waste using the Lipoval process. The properties of Lipofit are close to those of heavy fuel, except that is has a much lower sulfur content. Under regulations, it is considered a fuel in its own right, and can be used in facilities classified 2910B (combustion plants).

Lipoval
This separating process is designed for the treatment of liquid fatty waste mainly from restaurant gully traps (80%), but also from food industry and wastewater treatment plant oil extractors. The Lipoval process dynamically separates fatty waste into three phases: a fatty concentrate that can be used as a replacement fuel (Lipofit), solid sediment, and a treated aqueous phase discharged into the sewer.

Materials recovery
Direct reintroduction of a waste material in the production cycle by which it was generated, to replace new raw materials in whole or in part. For example, taking broken bottles (cullet), and remelting them to make new bottles.

Medical waste
Medical waste is generated by hospitals and healthcare professionals. It includes syringes, needles and other sharp instruments. Under no circumstances can these be put in conventional waste bins. Medical waste must be disposed of in compliance with national regulations.

Methane
CH4. A greenhouse gas (see Biogas and Greenhouse gases ).

Methane production
A natural method for treating organic waste. It leads to the production of gas (landfill gas or biogas) that can be converted into energy. The gas comes from the biological decomposition of organic matter in an air-deprived environment (known as “anaerobic digestion” because it is without oxygen). A digestate (“digested” waste) is also produced and can be used raw or after treatment (dewatering and composting, sanitization) as a compost.
Organic waste, which is rich in water and highly biodegradable, is used primarily for methane production. Organic waste includes putrescible household waste, wastewater treatment plant sludge, oil, grease and night soil, some agrifood industry waste and some agricultural waste.

Municipal outsourcing services
Public authorities can choose to outsource the public services or services of general interest for which they are responsible. Local residents then pay a service charge directly to the service provider. The service provider is responsible for operating the service and making certain investments as needed. These services
are mainly household and non-hazardous waste collection treatment and disposal, water distribution, wastewater collection and treatment, and public transportation.

Municipal waste
Household and other waste collected by municipalities. Its great diversity, and the leeway left to municipalities to collect or not certain types of waste, explains the lack of comprehensive figures in this area.

Non-hazardous industrial waste
All non-inert and non-hazardous waste produced by companies, industry, retailers, trades people and services: scrap iron, non-ferrous metals, paper-board, glass, textiles, wood, plastics, etc.

Organic matter
Organic matter in soil is made up of living organisms, plant and animal residue, and decomposing products. In general, it only represents between 0.5% and 10% of the soil’s mass. Organic matter disappears as a result of erosion, clearing or natural oxidation.
However, it boosts fertility and plays an essential role in the stability of the ecosystem. It therefore fulfills important environmental functions (preserving soil, protecting water resources and trapping carbon).
Produced from biodegradable waste, compost supplies organic matter to depleted soil. By increasing waste recycling for agricultural purposes, Onyx is helping to restore the land’s fertility while complying with very stringent quality and safety criteria.

Organic or biodegradable waste
Waste of vegetable or animal origin that can be broken down by microorganisms for which it is a source of nutrients.
It includes vegetable matter, putrescible food waste and waste collected from corporate canteens and restaurants, and, under certain conditions, dirty paper and cardboard.
This waste is used to make compost

Organic soil improver
A stable, dry product with high agricultural value. Organic soil improvers are generated by composting organic waste, which includes food waste, green waste and wastewater treatment sludge. Rich in humus, it is applied to land to improve various soil properties: physical: stabilization, aeration and erosion resistance;
chemical: fertilization and addition of trace elements; biological: strengthening of plant resistance and the soil’s biological activity.

Organic waste
Or biodegradable waste. Waste of vegetable or animal origin that can be broken down by microorganisms for which it is a source of nutrients.

Outsourcing
This is the subcontracting to an exterior operator of a group of peripheral activities previously carried out internally (water, energy, transportation, and environmental protection management, etc.). Some outsourcing contracts stipulate the integration of the relevant company’s employees in the subsidiaries created by the service provider.

Pollutant
Primary: a pollutant emitted directly by human activities or nature (sulfur dioxide, for example).
Secondary: a pollutant produced by the chemical interaction of primary pollutants in the atmosphere (ozone, for example).

Recycling
Reuse or recycling or any other action designed to obtain reusable material or energy from waste.

Recypulpe
Innovative process for the treatment of pulp mill waste from paper mills using recycled paper. The pulp mill waste is generated by recycling paper (a process that recovers the cellulose fiber and uses it to make new paper). The waste is a heterogeneous mixture of fiber, plastic, wood, metals, glues, etc. The Recypulpe technique separates out the plastics and fibers, which are then recycled.

Résoplast
The Résoplast unit produces fuel from waste plastic from industrial plants. The properties (homogeneity, calorific value, specific gravity, and composition) of the process’s fuels are comparable to those of standard fossil fuels used in certain heavy-energy consuming industrial sectors (cement works, lime plants, paper mills, etc). Résoplast is an alternative to landfilling non-recyclable industrial waste plastic, thereby saving natural hydrocarbon resources.

Scale house, weigh station, weighbridge
A structure used for weighing vehicles .

Screen
A type of large sieve used to sort and separate different types of waste: biodegradable waste from light packaging with plastic film, for example.

Selective collection
Collection of household solid waste, pre-sorted at the source (glass, paper, board, newspapers, magazines, plastics, fermentable waste, etc.), so that it can be recycled at specific treatment centers. Each round collects a different type of waste.

Sewer cleaning waste
Waste produced by the cleaning and maintenance of wastewater and storm water collection systems. It is predominantly organic (sludge, fats, waste from screening operations at wastewater treatment plants, oil, grease and night soil, etc.) and mineral waste (wastewater treatment sand and grit, sludge, sewer cleaning sand, residue from dredging rivers and canals, etc.).

Sludge
There are several different types of sludge depending on its source.
Primary sludge is generated in the settler-digesters of wastewater treatment plants It is rich in mineral substances such as microsand and earth, and contains organic matter.
Physicochemical sludge is a variant of primary sludge obtained by the addition of reagents such as iron salt and aluminum to agglomerate the fine particles in wastewater.
Biosolids, or secondary sludge. It is generated by the biological treatment of wastewater.
Sludge may be disposed of in four different ways depending on its quality and composition: land application, landfill, incineration or composting.

Subcell
A pit into which waste is deposited in a landfill. Landfills are divided into cells, which are subdivided into subcells.


Thermal desorption
Method for decontaminating polluted soil by heating it to between 400°C and 600°C so that the pollutants are volatilized; the dust is extracted from the resultant gas in sleeve filters. Thermal desorption almost entirely decontaminates soil: it is appropriate for heavy hydrocarbons (heavy fuel, tars and PAH) and light hydrocarbons (solvents: benzene, toluene, and xylene). Treated soil can be used as backfill. The process does not generate odors or waste.

Transfert station
Waste collected from municipalities or industrial sites transits via a transfer station, where it is sorted and forwarded for treatment or disposal as appropriate. Recyclable waste is sent to recycling or treatment plants; non-recyclable waste is sent to incineration plants or landfills.

Urban or district heating networks
Comprising a central production unit and a reticulated network, they provide heating and air conditioning to public and private institutions (schools, hospitals, offices and dwellings).

Valorization
The reuse or recycling or any other action designed to obtain reusable material or energy from waste.

Vehicule natural gas (VNG)
Natural gas consists mainly of methane. Compressed at 200 bar, it is used as an alternative fuel in gaseous form. The combustion of natural gas produces no sulfur, lead or particles, and only a little nitrogen oxide. It does not generate black smoke or odors.
Natural gas fuel burns more slowly than other hydrocarbons. It also significantly reduces vibrations, thereby reducing engine noise. The noise level is lowered by about 4 decibels, which is the equivalent of half the noise generated by a diesel engine. Methane can be extracted from natural reserves or produced from biomass (green waste).

Waste collection operative
A garbage collector or public snitation worker who collects household or specific waste.

Waste disposal center
An enclosed area where people can deposit, free of charge, any waste that is not collected in a conventional manner: bulky waste (household appliances and IT equipment, furniture, etc.), toxic products, inflammable products, pollutants (engine oil, car batteries, paint, solvents, etc.), green waste (grass clippings, pruning waste, dead leaves, etc.), construction and demolition waste, scrap metal and so on. The waste is then forwarded to appropriate recycling centers.

Waste-to-energy conversion
Waste contains energy in the form of calories, which are released by burning and recovered to produce electricity and/or heat and/or steam This can then be used, for example, for heating buildings.
Because of its energy potential, biogas is also recovered for heat, steam or electricity production , cogeneration (combined production of electricity and heat), conversion to vehicle fuel, or reinjection into the gas distribution network.

Waste-to-energy plants
Waste incineration plants that recover energy to produce electricity or supply a heating network.

Wastewater collection system
The public sewer system that collects and transports wastewater to a treatment plant.

Wastewater treatment plant
Receives and treats wastewater generated by households (and industry) connected to the collection system, together with storm water (in combined systems). The plant discharges water into the natural environment after treatment to make it compliant with limits set by the authorities. The treatment also produces a residue known as sludge

WEE - Waste from Electrical and Electronic Equipment
Electrical and electronic equipment is producing a growing volume of municipal household waste: brown goods (TVs, radios, telephones, etc.); white goods (refrigerators, etc.); and gray goods (computers). The volume of this waste is growing constantly (including heavy metals and halogen compounds), and is likely to harm the environment if not adequately treated prior to disposal.

Windrow
A professional term to describe the action of arranging waste to be composted into long, high rows (windrows) in order to facilitate its decomposition.