Sulfate aerosols Particulate matter that consists of compounds of sulfur formed by
the interaction of sulfur dioxide and sulfur trioxide with other compounds in the
atmosphere. Sulfate aerosols are injected into the atmosphere from the combustion of fossil fuels and the eruption of volcanoes like Mt. Pinatubo. Sulfate
aerosols can lower the Earth’s temperature by reflecting away solar radiation
(negative radiative forcing). General Circulation Models, which incorporate the
effects of sulfate aerosols more accurately, predict global temperature variations.
Sulfur hexafluoride (SF 6 ) A colorless gas soluble in alcohol and ether, slightly
soluble in water. A very powerful greenhouse gas used primarily in electrical
transmission and distribution systems and as a dielectric in electronics. The global
warming potential of SF6 is 22,800. This GWP is from the IPCC’s Fourth
Assessment Report (AR4).
Super It is a part of commercial or other managed beehive that is used to collect
surplus honey. Normally, it is placed over or above the brood chamber.
Supernatant Liquid removed from settling sludge. Supernatant commonly refers
to the liquid between the sludge on the bottom of an anaerobic digester and the
scum on the surface. The liquid is usually returned to the influent wet well or to
the primary clarifier.
Supracell It is a circular dissolved air flotation (DAF) clarifier designed by the
Lenox Institute of Water Technology (LIWT) and manufactured by Krofta
Engineering Corporation (KEC).
Surface water Surface water is water on the surface of continents such as in a river,
lake, or wetland. It can be contrasted with groundwater and atmospheric water.
Nonsaline surface water used is replenished by precipitation and by recruitment
from ground-water.
Surfactant A surface active compound that lowers the surface tension
(or interfacial tension) between two liquids, between a gas and a liquid, or
between a liquid and a solid. Surfactants may act as detergents, wetting agents,
emulsifiers, foaming agents, etc.
Surplus honey It is the honey removed from the hive, which exceeds what is
needed by bees for their own use.
Suspended solid Solids that either float on the surface or are suspended in water,
wastewater, or other liquids, and which are largely removable by laboratory
filtering.
Suspended-growth biological processes In a suspended-growth biological process
system, biomass or microorganisms are suspended in the biological reactors for
aerobic and/or anoxic biochemical reactions. They include all kinds of activated
sludge processes as well as oxidation ditch process, such as (a) conventional
activated sludge process using diffused aeration; (b) conventional activated
sludge process using mechanical aeration; (c) high rate activated sludge process
using diffused aeration; (d) pure oxygen activated sludge process using covered
reactor; (e) pure oxygen activated sludge process using uncovered reactor;
(f) extended aeration activated sludge process with nitrification; (g) activated
sludge process separate reactors for carbonaceous oxidation, nitrification, and
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the interaction of sulfur dioxide and sulfur trioxide with other compounds in the
atmosphere. Sulfate aerosols are injected into the atmosphere from the combustion of fossil fuels and the eruption of volcanoes like Mt. Pinatubo. Sulfate
aerosols can lower the Earth’s temperature by reflecting away solar radiation
(negative radiative forcing). General Circulation Models, which incorporate the
effects of sulfate aerosols more accurately, predict global temperature variations.
Sulfur hexafluoride (SF 6 ) A colorless gas soluble in alcohol and ether, slightly
soluble in water. A very powerful greenhouse gas used primarily in electrical
transmission and distribution systems and as a dielectric in electronics. The global
warming potential of SF6 is 22,800. This GWP is from the IPCC’s Fourth
Assessment Report (AR4).
Super It is a part of commercial or other managed beehive that is used to collect
surplus honey. Normally, it is placed over or above the brood chamber.
Supernatant Liquid removed from settling sludge. Supernatant commonly refers
to the liquid between the sludge on the bottom of an anaerobic digester and the
scum on the surface. The liquid is usually returned to the influent wet well or to
the primary clarifier.
Supracell It is a circular dissolved air flotation (DAF) clarifier designed by the
Lenox Institute of Water Technology (LIWT) and manufactured by Krofta
Engineering Corporation (KEC).
Surface water Surface water is water on the surface of continents such as in a river,
lake, or wetland. It can be contrasted with groundwater and atmospheric water.
Nonsaline surface water used is replenished by precipitation and by recruitment
from ground-water.
Surfactant A surface active compound that lowers the surface tension
(or interfacial tension) between two liquids, between a gas and a liquid, or
between a liquid and a solid. Surfactants may act as detergents, wetting agents,
emulsifiers, foaming agents, etc.
Surplus honey It is the honey removed from the hive, which exceeds what is
needed by bees for their own use.
Suspended solid Solids that either float on the surface or are suspended in water,
wastewater, or other liquids, and which are largely removable by laboratory
filtering.
Suspended-growth biological processes In a suspended-growth biological process
system, biomass or microorganisms are suspended in the biological reactors for
aerobic and/or anoxic biochemical reactions. They include all kinds of activated
sludge processes as well as oxidation ditch process, such as (a) conventional
activated sludge process using diffused aeration; (b) conventional activated
sludge process using mechanical aeration; (c) high rate activated sludge process
using diffused aeration; (d) pure oxygen activated sludge process using covered
reactor; (e) pure oxygen activated sludge process using uncovered reactor;
(f) extended aeration activated sludge process with nitrification; (g) activated
sludge process separate reactors for carbonaceous oxidation, nitrification, and
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487