New Brunswick's Clean Air Act - Glossary

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Dechlorination Tower
A tower-like device in which chlorine is removed from an air waste stream or process stream in order to clean the air waste stream or to precondition the process stream. The dechlorination occurs by chemically replacing chlorine with either hydrogen, or hydroxide ions.

Decision
When used in context with the Appeals Regulation, means the findings of fact and conclusions of law which must be in writing and filed with the clerk.

Degree of Seriousness
In the context of Section 4 of the Administrative Penalties Regulation means the extent to which a statutory or regulatory provision was allegedly breached. This is based on whether it was considered to be a minor, moderate or major deviation from the provision.

Degree of Willfulness or Negligence

In the context of Section 4(4) of the Administrative Penalties Regulation, means the extent to which one purposely failed to take the proper action or reasonable care to prevent the emission of pollutants.

Dehydrator
A vessel or unit operation used for the removal of liquids (mostly water or moisture) from gases or solids by the use of heat, absorbents or adsorbents.

Demineralizer Regeneration Tank
A vessel or unit operation used for water treatment to remove minerals that accumulate in the process water used in the Chlor-Alkali process (manufacture of chlorine and sodium hydroxide from the electrolysis of brine), which produces chlorine and caustic soda concurrently.

Designation
With respect to Section 3 of the Appeal Regulation, means to distinguish a class or category.

Desulphurization Units
Unit operations used in the Oil Refining Industry and Power Plant Industry to remove sulphur and/or sulphur compounds or other compounds from an air waste stream or process stream before being emitted into the atmosphere or circulated for further processing.

Deviation
With respect to statutory or regulatory provision, means failing to follow the statutes and regulations as set by the Minister.

Dialkyl Sulphides
Complex sulphur compounds that are typically removed by the desulphurization units in the Oil Refining Industry.

Diesel Fuel
Any petroleum liquid, sold in any province that is suitable for use as a fuel source in a diesel engine. In the Oil Refining Industry diesel fuel is usually that fraction of crude oil that distills after kerosene and is equivalent to the No.2 grade of domestic fuel oil.

Diluted Waste
Waste that has mixed with other solutions that do not contain the wastes and therefore, the waste stream becomes less concentrated.

Direct Fired Triple Pass Dryer
A device or unit operation used to dry a process stream that has a high moisture content. In a direct fired triple pass dryer the stream is passed three times through the dryer column or drum and is in direct contact with the burner unit to provide the desired dryness. Dryers are typically used to dry wood (shavings) chips, aggregate mixtures, and mined materials.

Discharge Stack
A chimney, flue, duct or vertical pipe that releases an air waste stream to the ambient air. Also see Stack.

Dispersion
Refers to the mixing of contaminants being released to the atmospheric environment with the surrounding atmosphere. Good dispersion will dilute the concentration of the contaminants being released and therefore, reduce the potential deleterious impacts associated with the release of contaminants to the environment. There are a number of parameters that impact the effectiveness of dispersion in the atmosphere, which include but are not limited to, atmospheric stability, pressure systems, moisture, wind, and stack height.

Dispersion Coefficients
The plume of an air waste stream being emitted from a stack which shows a Gaussian Distribution in the horizontal and vertical directions. Standard deviations of the distribution in the horizontal and vertical direction at specific points downwind can be determined. These determined standard deviations are referred to as the dispersion coefficients. Also see Plume.

Dispose of
With respect to equipment or an ozone depleting substance, to cease to have charge of or responsibility for equipment or an ozone depleting substance, with the intention that it is not to be used again by the person disposing of it.

Disposition
With respect to ozone depleting substances, means the act of disposing of the substances, or transferring them to the care or possession of another.

Dissolving Tank Vent
In the Pulp and Paper process, the vent associated with the dissolving tank that contains the molten smelt, which flows from the smelt bed in a recovery furnace, and steam shatter sprays and produces green liquor. Large amounts of steam are released when the smelt contacts the water and some particulate matter is carried out of the vent with the steam. The vents, therefore, should be circulated to a control device before being released to the atmosphere.

Distillation
The separating of a mixture of liquids with different boiling point ranges using elevated temperatures. The temperature is increased so that various liquids boil off and are condensed to a liquid of specific purity and the higher boiling parts that did not boil remain in a concentrated residue.

Distillation Towers
A tower-like device used to separate the various mixtures of hydrocarbon compounds in Crude Oil refining operations into common boiling-point fractions. These towers can be atmospheric, or vacuum distillation towers.

Dried Catalytically
A substance dried with the assistance of a catalyst to promote the drying reaction.

Dross
An impurity, usually an oxide, formed in the surface of a molten metal.

Drug Identification Number. A unique identification number assigned to drugs and pharmaceuticals under the Food and Drugs Act (Canada).

Dry Black Liquor Solids
The amount of solids that are found in a sample of black liquor. Weak Black Liquor contains about 20% solids and is sent on to direct contact evaporators, which evaporate off the liquid and bring the Dry Black Liquor Solids to approximately 65 % solids. At this percentage the Black Liquor is then circulated to the Recovery Boiler for combustion of the organic component. See Black Liquor.

Dry Crushing Area
An area referenced predominately in the Mining or Quarrying Industry and refers to the area where the dried mined material is directed to be crushed in to specific sizes or grades, which could include course, standard and fine.

Drying Towers
A tower-like device that performs the same functions as a dryer. Which is a device heated by a combustion reaction that utilizes the heat to dry process materials to various levels of dryness. The main components of a dryer include the drum, burner and fuel source and exhaust stack.

Dust Collection
The activities associated with collecting dust emissions from an industrial process. Involves localized ventilation in areas where dust emissions are predominant and piping to a common duct that enters an air pollution control device designed to remove the dust from the air waste stream before being emitted to the atmosphere. Some of these technologies include but are not limited to baghouses, electrostatic precipitators, and wet scrubbers.

Dust Suppressants
Approved solutions applied to site access roads, and aggregate storage piles. The solutions are used to suppress most of the fugitive dust emissions originating from the access roads and storage piles as a result of high winds and high vehicle traffic. Dust suppressants are being used mostly by Mines, Rock Quarries, and Asphalt Paving industries.