Cationic polymer (or cationic polyelectrolyte) A positively charged electrolyte
used as a coagulant to aid in separating (settling or floating) solids in water or
wastewater.
Cationic surfactant (a) A positively charged surface active agent that lowers the
surface tension in water, and can be used as a collector in a flotation process, or as
an organic disinfectant in personal cleaners, swimming pools, house roofs,
restaurants, etc. (b) an organic quaternary ammonia compound with positively
charged surface active moieties.
Cavitation The formation and collapse of a gas pocket or bubble on the blade of an
impeller or the gate of a valve. The collapse of this gas pocket or bubble drives
water into the impeller or gate with a terrific force that can cause pitting on the
impeller or gate surface. Cavitation is accompanied by loud noises that sound like
someone is pounding on the impeller or gate with a hammer.
Centrate Dilute effluent stream from a centrifuge.
Centrifuge (a) It is a water-solid separation device that separates the solids from
liquid by centrifugal force. Centrifuges are used for separating liquids of different
density, thickening slurries, or dewatering solids. (b) It is a mechanical device that
uses centrifugal or rotational forces to separate solids from liquids.
Centrifuge thickening It is sludge preliminary concentration process before sludge
watering process involving the use of centrifugal force. Water in a wet dilute
sludge is forced out of the wet sludge placed in the spinning drum of a centrifuge.
Centrifuge, basket centrifuge for sludge thickening/dewatering They are suitable for small plants. It is a semibatch type operation. Sludge cake is collected on
the sides of the spinning bowl while the centrate (dilute effluent stream from the
centrifuge) overflows the bowl rim. Once solids have built up to a maximum
thickness, the feed sludge is stopped and scrapper blades peel the sludge from the
walls. The process is then resumed.
Centrifuge, solids bowl centrifuge for sludge thickening/dewatering Sludge is
fed at a constant flowrate into the rotating bowl where it is separated into a dense
cake and a dilute stream called centrate. The centrifuge units can be used with no
prior chemical conditioning, but solids caputer and centrate quality are improved
considerably when the sludge is conditioned with polymer.
Ceramic matrices Materials like clay that can be converted to ceramics after high
temperature treatment.
Characteristic Wastes In the USA, characteristic wastes may be regulated for
exhibiting one of the four characteristics (ignitability, corrosivity, reactivity,
and toxicity) of the waste as determined by the US Environmental Protection
Agency (USEPA).
Chemical engineering It is a branch of engineering that uses principles of chemistry, physics, mathematics, biology, and economics to efficiently use, produce,
design, transport, and transform energy and materials. The work of chemical
engineers can range from the utilization of nanotechnology and nanomaterials in
the laboratory to large-scale industrial processes that convert chemicals, raw
materials, living cells, microorganisms, and energy into useful forms and products.
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M.-H. S. Wang and L. K. Wang
used as a coagulant to aid in separating (settling or floating) solids in water or
wastewater.
Cationic surfactant (a) A positively charged surface active agent that lowers the
surface tension in water, and can be used as a collector in a flotation process, or as
an organic disinfectant in personal cleaners, swimming pools, house roofs,
restaurants, etc. (b) an organic quaternary ammonia compound with positively
charged surface active moieties.
Cavitation The formation and collapse of a gas pocket or bubble on the blade of an
impeller or the gate of a valve. The collapse of this gas pocket or bubble drives
water into the impeller or gate with a terrific force that can cause pitting on the
impeller or gate surface. Cavitation is accompanied by loud noises that sound like
someone is pounding on the impeller or gate with a hammer.
Centrate Dilute effluent stream from a centrifuge.
Centrifuge (a) It is a water-solid separation device that separates the solids from
liquid by centrifugal force. Centrifuges are used for separating liquids of different
density, thickening slurries, or dewatering solids. (b) It is a mechanical device that
uses centrifugal or rotational forces to separate solids from liquids.
Centrifuge thickening It is sludge preliminary concentration process before sludge
watering process involving the use of centrifugal force. Water in a wet dilute
sludge is forced out of the wet sludge placed in the spinning drum of a centrifuge.
Centrifuge, basket centrifuge for sludge thickening/dewatering They are suitable for small plants. It is a semibatch type operation. Sludge cake is collected on
the sides of the spinning bowl while the centrate (dilute effluent stream from the
centrifuge) overflows the bowl rim. Once solids have built up to a maximum
thickness, the feed sludge is stopped and scrapper blades peel the sludge from the
walls. The process is then resumed.
Centrifuge, solids bowl centrifuge for sludge thickening/dewatering Sludge is
fed at a constant flowrate into the rotating bowl where it is separated into a dense
cake and a dilute stream called centrate. The centrifuge units can be used with no
prior chemical conditioning, but solids caputer and centrate quality are improved
considerably when the sludge is conditioned with polymer.
Ceramic matrices Materials like clay that can be converted to ceramics after high
temperature treatment.
Characteristic Wastes In the USA, characteristic wastes may be regulated for
exhibiting one of the four characteristics (ignitability, corrosivity, reactivity,
and toxicity) of the waste as determined by the US Environmental Protection
Agency (USEPA).
Chemical engineering It is a branch of engineering that uses principles of chemistry, physics, mathematics, biology, and economics to efficiently use, produce,
design, transport, and transform energy and materials. The work of chemical
engineers can range from the utilization of nanotechnology and nanomaterials in
the laboratory to large-scale industrial processes that convert chemicals, raw
materials, living cells, microorganisms, and energy into useful forms and products.
434
M.-H. S. Wang and L. K. Wang