Aerobic composting: a method of composting organic wastes using bacteria that need oxygen. This requires that the waste be exposed to air, either via turning or by forcing air through pipes that pass through the material.

 

Anaerobic composting: decomposition of organic wastes by micro-organisms, usually under wet conditions, in the absence of oxygen, to produce a gas comprising mostly methane and carbon dioxide.

 

Assimilated waste (AW): waste streams similar in composition and nature to municipal solid waste. From the characteristics and composition point of view, municipal solid waste and assimilated waste are similar.

 

Build-Own-Operate-Transfer (BOOT): The situation when a private owner builds, owns, and operates an infrastructure facility and then transfers it to another entity after a specified period.

 

Build-Own-Transfer (BOT): The situation when a private owner builds, owns, and then transfers an infrastructure facility to another party, often at no cost, after a specified period.

 

Build-Transfer-Operate (BTO): The situation when a private owner builds an infrastructure facility, transfers it to another entity, and then operates it on a contractual basis for a specified period.

 

Composting: controlled microbial degradation of non hazardous organic waste yielding an environmentally sound product (‘compost’) with value as a soil ammendment.

 

Energy recovery: the process of extracting useful energy from waste, typically from the heat produced by incineration or via methane gas from landfills.

 

Fluidized-bed incinerator: a type of incinerator made up of a vertical cylinder that contains a bed of sand held in suspension (fluidified) by high-velocity air injected through a grid at the base of the cylinder. The waste products are fed into and burned on the sand bed, which enhances the heat exchange process and supplies sufficient thermal inertia to the system to regulate the combustion process. The plant has extensive gas washing equipment and an energy recovery system.

 

Grate incinerator: a type of incinerator in which waste is fed at the top part of an inclined stoker grate. The waste passes over the upper drying section where moisture is removed and descends into the lower burning section. Ash is removed at the lower part of the grate. Waste is burnt at an average temperature of 850° C. The plant has extensive gas washing equipment and an energy recovery system.

 

Hazardous Waste: solid, liquid, viscous or gaseous substance which, because of its source or measurable characteristics, is classified as potentially dangerous and is subject to specific legal regulations and special handling, shipping, and disposal requirements.

 

Incineration: process of high-temperature combustion (between 850°C and 1200°C) in the presence of oxygen. Incineration is utilized to destroy waste and the hazardous constituents thereof.

 

(Sanitary) landfill: an engineered method of disposing of solid waste on land, including sound siting, extensive site preparation (with clay and/or synthetic liners to prevent releases to ground water), proper leachate and gas management and monitoring, compaction, final cover, complete access control, and record-keeping.

 

Municipal solid waste (MSW): waste generated in households and assimilated waste generated in commercial establishments, institutions, and businesses. MSW includes used paper and cardboard, waste wood, plastic bottles, metal packaging and drink cartons, organic waste such as green waste, vegetable, fruit and garden waste and non-recyclable residual waste.

 

Packaging waste: set of waste streams consisting of plastic bottles, metal packaging and drink cartons.

 

Physico-chemical treatment unit: processing unit providing in the neutralisation of acids and bases, the oxidation of cyanides, the reduction of chromates (mainly haxavelant chromium) and the immobilisation of heavy metals.

 

Recovery: processes for recovering usable materials from wastes. Usable portions are isolated from unusable materials by mechanical or manual separation and chemical or thermal separation processes.

 

Recycling: process of sorting, cleansing, treating, and reconstituting materials that would otherwise become solid waste, and returning them into material for new, reused, or reconstituted products that meet the quality standards necessary to be used in the marketplace.

 

(Recycling centre: (here) centre where discarded but re-usable goods such as furniture, cutlery, clothes, books and electronics are attracted in order to sell them to the public. The aim is to divert as much waste as possible from the final disposal to the recycling operation.)

 

Roasting kiln: type of incinerator used for the regeneration of hydrochloric acid

 

Rotary kiln: type of incinerator mainly used for the thermal treatment of hazardous waste. A rotary kiln is made up of a slightly inclined cylinder that rotates to facilitate the constant advancement of the waste being fed in. The waste is fed into the upper extreme of the kiln, and the combustion residue is deposited from the opposite (lower) end. The plant has extensive gas washing equipment and an energy recovery system.

 

Solidification: adding cementious materials (e.g. cement, lime, fly ash) to a liquid/semi-liquid wastestream to render it solid and limit the solubility of the hazardous constituents in a chemical and physical way.

 

Static kiln: type of incinerator which is appropriate exclusively for liquid waste. Essentially it is a combustion chamber with no moving parts, into which the waste to be incinerated is fed. The plant has extensive gas washing equipment.

 

Thin film evaporator: processing unit used to recycle polluted solvents through evaporation.