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| Abiotic factors: |
Non living; moisture, soil, nutrients, fire, wind,
temperature, climate |
| Absorption: |
The taking in or soaking up of one substance into the
body of another by molecular or chemical action (as tree roots absorb
dissolved nutrients in the soil). |
| Absorption Field: |
A system of properly sized and constructed narrow
trenches partially filled with a bed of washed gravel or crushed stone
into which perforated or open joint pipe is placed. The discharge from
the septic tank is distributed through these pipes into trenches and
surrounding soil.While seepage pits normally require less land area to
install, they should be used only where absorption fields are not
suitable and well-water supplies are not endangered. |
| Acid: |
A substance that dissolves in water with the formation
of hydrogen ions, contains hydrogen which may be replaced by metals to
form salt, and/or is corrosive. |
| Acidity: |
The capacity of water or wastewater to neutralize bases.
Acidity is expressed in milligrams per liter of equivalent calcium
carbonate. Acidity is not the same as pH. |
| Activated sludge: |
Sludge particles produced in raw or settled wastewater
(primary effluent) by the growth of organisms (including zoogleal
bacteria) in aeration tanks in the presence of dissolved oxygen. The
term "activated" comes from the fact that the particles are teeming with
fungi, bacteria, and protozoa. Activated sludge is different from
primary sludge in that the sludge particles contain many living
organisms which can feed on the incoming wastewater. |
| Adsorption: |
The gathering of a gas, liquid, or dissolved substance
on the surface or interface zone of another substance. |
| ADP: |
Adenosine diphosphate. See ATP. |
| Aeration: |
The process of adding air to water. In wastewater
treatment, air is added to freshen wastewater and to keep solids in
suspension. |
| Aeration tank: |
The tank where raw or settled wastewater is mixed with
return sludge and aerated. This is the same as an aeration bay, aerator,
or reactor. |
| Aerobe: |
An organism that requires free oxygen for growth. |
| Alkaline substance: |
Chemical compounds in which the basic hydroxide (OH-)
ion is united with a metallic ion, such as sodium hydroxide (NaOH) or
potassium hydroxide (KOH). These substances impart alkalinity to water
and are employed for neutralization of acids. Lime is the most commonly
used alkaline material in wastewater treatment. |
| Alum: |
Astringent crystalline double sulfate of an alkali.
K2SO4AL2 (SO4)3 24H2O. Used in the processing of pickles and as a
flocking agent. Excess aluminum in the environment can be hazardous. |
| Ammonia oxidation: |
Test drawn during manufacturing process to evaluate the
ammonia oxidation rate for the nitrifiers. |
| Ambient temperature: |
Temperature of the surroundings. |
| Anaerobe: |
An organism that lives and reproduces in the absence of
dissolved oxygen, instead deriving oxygen from the breakdown of complex
substances. |
| Anhydrous: |
Very dry. No water or dampness is present. |
| Anion: |
A negatively charged ion in an electrolyte solution,
attracted to the anode under the influence of a difference in electrical
potential. Chloride is an anion. |
| API separator: |
A facility developed by the Committee on Disposal or
Refinery Wastes of the American Petroleum Institute for separation of
oil from wastewater in a gravity differential and equipped with means
for recovering the separated oil and removing sludge |
| Aseptic: |
Free from living germs of disease, fermentation or
putrefaction. |
| Assimilate: |
To take in, similar to eating food. |
Attached growth
processes: |
Wastewater treatment processes in which the
microorganisms and bacteria treating the wastes are attached to the
media in the reactor. The wastes being treated flow over the media.
Trickling filters, bio-towers, and RBCs are attached growth reactors.
These reactors can be used for removal of BOD, nitrification, and
denitrification. |
| ATP: |
Adenosine triphosphate. Chemical energy generated by
substrate oxidations is conserved by formation of high-energy compounds
such as adenosine diphosphate (ADP) and adenosine triphosphate (ATP) or
compounds containing the thioester bond |
| Autotrophy: |
A unique form of metabolism found only in bacteria.
Inorganic compounds (e.g., NH3, NO2-, S2, and Fe2+) are oxidized
directly (without using sunlight) to yield energy. This metabolic mode
also requires energy for CO2 reduction, like photosynthesis, but no
lipid-mediated processes are involved. This metabolic mode has also been
called chemotrophy, chemoautotrophy, or chemolithotrophy. |
| AWT: |
Advanced Waste Treatment - any process of water
renovation that upgrades treated wastewater to meet reuse requirements. |
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| Bacteria: |
Living organisms, microscopic in size, which usually
consist of a single cell. Most bacteria use organic matter for their
food and produce waste products as a result of their life processes. |
Bacterial
Photosynthesis: |
A light-dependent, anaerobic mode of metabolism. Carbon dioxide is
reduced to glucose, which is used for both biosynthesis and energy
production. Depending on the hydrogen source used to reduce CO2, both
photolithotrophic and photoorganotrophic reactions exist in bacteria. |
| Base: |
A substance which dissociates (separates) in aqueous solution to
yield hydroxyl ions, or one containing hydroxyl ions (OH-) which reacts
with an acid to form a salt or which may react with metal to form a
precipitate. |
| Batch process: |
A treatment process in which a tank or reactor is filled, the
wastewater (or solution) is treated or a chemical solution is prepared
and the tank is emptied. The tank may then be filled and the process
repeated. Batch processes are also used to cleanse, stabilize or
condition chemical solutions for use in industrial manufacturing and
treatment processes. |
| Bench scale analysis: |
Also known as: "bench test". A method of studying different ways of
treating wastewater and solids on a small scale in a laboratory. |
| Benzene: |
An aromatic hydrocarbon which is a colorless, volatile, flammable
liquid. Benzene is obtained chiefly from coal tar and is used as a
solvent for resins and fats in dye manufacture. |
| Binary fission: |
During binary fission, a single cell divides transversely to form
two new cells called daughter cells. Both daughter cells contain an
exact copy of th geneticinformation contained in the parent cell. |
| Biocatalysis: |
Chemical reactions mediated by biological systems (microbial
communities, whole organisms or cells, cell-free extracts, or purified
enzymes aka catalytic proteins). |
| Biotic potential: |
All the factors that contribute to a species
increasing its number. Reproduction, migration, adaptation etc. |
| BOD: |
Biochemical Oxygen Demand - the rate at which microorganisms use the
oxygen in water or wastewater while stabilizing decomposable organic
matter under aerobic conditions. In decomposition, organic matter serves
as food for the bacteria and energy results from this oxidation. |
| BOD test: |
A procedure that measures the rate of oxygen use under controlled
conditions of time and temperature. Standard test conditions include
dark incubation at 20 C for a specified time (usually 5 days). |
| Biodegradable: |
Organic matter that can be broken down by bacteria to more stable
forms which will not create a nuisance or give off foul odors. |
| Biofilm: |
A slime layer which naturally develops when bacteria attach to an
inert support that is made of a material such as stone, metal, or wood.
There are also non-filamentous bacteria that will produce an
extracellular polysaccharide that acts as a natural glue to immobilize
the cells. In nature, nonfilament-forming microorganisms will stick to
the biofilm surface, locating within an area of the biofilm that
provides an optimal growth environment (i.e., pH, dissolved oxygen,
nutrients). Since nutrients tend to concentrate on solid surfaces, a
microorganism saves energy through cell adhesion to a solid surface
rather than by growing unattached and obtaining nutrients randomly from
the medium. Pseudomonas and Nitrosomonas strains are
especially well known for their ability to form a strong biofilm. |
| Bioflocculation: |
The clumping together of fine, dispersed organic particles by the
action of certain bacteria and algae. |
| Biomass: |
A mass or clump of living organisms feeding on the wastes in
wastewater, dead organisms and other debris. |
| Biostimulation: |
Any process that increases the rates of biological degradation,
usually by the addition of nutrients,oxygen, or other electron donors
and acceptors so as to increase the number of indigenous microorganisms
available for degradation of contaminants. |
| Bio-Tower: |
An attached culture system. A tower filled with a media similar to
rachet or plastic rings in which air and water are forced up a
counterflow movement in the tower. |
| Blinding: |
The clogging of the filtering medium of a microscreen or a vacuum
filter when the holes or spaces in the media become sealed off due to a
buildup of grease or the material being filtered. |
| Buffer: |
A solution or liquid whose chemical makeup neutralizes acids or
bases without a great change in pH. |
| Bulking sludge: |
Clouds of billowing sludge that occur throughout secondary
clarifiers and sludge thickeners when sludge becomes too light and will
not settle properly. In the activated sludge process, bulking is usually
caused by filamentous bacteria. |
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Cation exchange
capacity: |
The ability of a soil or other solid to exchange cations
(positive ions such as calcium) with a liquid. |
| Cess Pools: |
This system is similar to a septic tank. in performance. Sewage
water usually seeps through the open bottom and portholes in the sides
of the walls. These can also clog up with overuse and the introduction
of detergents and other material which slow up the bacterial action. |
| CFU: |
Viable micro-organisms (bacteria, yeasts & mould) capable of growth
under the prescribed conditions (medium, atmosphere, time and
temperature) develop into visible colonies (colony forming units) which
are counted. The term colony forming unit (CFU) is used because a colony
may result from a single micro-organism or from a clump / cluster of
micro-organisms. More Info. |
| Chemoautotroph: |
An organism that obtains its energy from the oxidation of chemical
compounds and uses only organic compounds as a source of carbon.
Example: nitrifiers. |
| Chemotroph: |
An organism that obtains its energy from the oxidation of chemical
compounds. |
| Chemical precipitation: |
Precipitation induced by addition of chemicals; the process of
softening water by the addition of lime and soda ash as the
precipitants. |
| Chloramines: |
Compounds formed by the reaction of hypochlorous acid (or aqueous
chlorine) with ammonia. |
| Chlorination: |
The application of chlorine to water or wastewater, generally for
the purpose of disinfection, but frequently for accomplishing other
biological or chemical results. |
| Ciliates: |
A class of protozoans distinguished by short hairs on all or part of
their bodies. |
| COD: |
Chemical oxygen demand - the amount of oxygen in mg/l required to
oxidize both organic and oxidizable inorganic compounds. |
| Clarification: |
A process in which suspended material is removed from a wastewater.
This may be accomplished by sedimentation, with or without chemicals, or
filtration. |
| Clarifier: |
Settling tank, sedimentation basin. A tank or basin in which
wastewater is held for a period of time, during which the heavier solids
settle to the bottom and the lighter material will float to the water
surface. |
| Coagulants: |
Chemicals which cause very fine particles to clump (floc) together
into larger particles. This makes it easier to separate the solids from
the water by settling, skimming, draining, or filtering. |
| Coliform bacteria: |
Non-pathogenic microbes found in fecal matter that indicate the
presence of water pollution; are thereby a guide to the suitability for
potable use. |
| Colloids: |
Very small, finely divided solids (particles that do not dissolve)
that remain dispersed in a liquid for a long time due to their small
size and electrical charge. |
Combined available
chlorine: |
The concentration of chlorine which is combined with ammonia (NH3)
as chloramine or as other chloro derivatives, yet is still available to
oxidize organic matter. |
| Combined sewer: |
A sewer designed to carry both sanitary wastewaters and storm or
surface-water runoff. |
| Commensalism: |
When two organisms coexist, one organism benefits, the other is not
affected. |
| Comminution: |
Shredding. A mechanical treatment process which cuts large pieces of
waste into smaller pieces so that they won't plug pipes or damage
equipment. |
| Contact stabilization: |
Contact stabilization is a modification of the conventional
activated sludge process. In contact stabilization, two aeration tanks
are used. One tank is for separate reaeration of the return sludge for
at least four hours before it is permitted to flow into the other
aeration tank to be mixed with the primary effluent requiring treatment. |
| Conventional treatment: |
The preliminary treatment, sedimentation, flotation, trickling
filter, rotating biological contactor, activated sludge and chlorination
of wastewater. |
| Conversion: |
Changing from one substance to another. As food matter is changed to
cell growth or to carbon dioxide. |
| CRT: |
Cell residence time - the amount of time in days that an average
"bug" remains in the process. Also termed "sludge age". |
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| DAF: |
Dissolved air flotation - one of many designs for waste
treatment |
| Declining growth: |
A growth phase in which the availability of food begins to limit
cell growth. |
| Degradation: |
A growth phase in which the availability of food begins to limit
cell growth. |
| Denitrification: |
An anaerobic biological reduction of nitrate nitrogen to nitrogen
gas, the removal of total nitrogen from a system, and/or an anaerobic
process that occurs when nitrite ions are reduced to nitrogen gas and
bubbles are formed as a result of this process. The bubbles attach to
the biological floc in the activated sludge process and float the floc
to the surface of the secondary clarifiers. This condition is often the
cause of rising sludge observed in secondary clarifiers or gravity
thickeners. (See Nitrification) |
| Detritus: |
Dead plant and animal matter, usually consumed by bacteria, but some
remains. |
| Dew Point: |
The temperature to which air with a given quantity of water vapor
must be cooled to cause condensation of the vapor in the air. |
| D/I unit: |
Deionizing unit, frequntly used to maintain water quality in
aquariums. Advantages: does not waste water like the R/O unit, is
designed to be hooked up to either a faucet or household piping system,
the anion & cation resins can be regenerated (with another expensive
unit) indefinitely, and these systems allow a larger water flow (up to
2,000 gallons a day), than an R/O system, but cost dramatically more
too. |
| Diatomaceous earth: |
A fine, siliceous (made of silica) "earth" composed mainly of the
skeletal remains of diatoms (single cell microscopic algae with rigid
internal structure consisting mainly of silica). Tests prove that DE
leaches unacceptable amounts of silicate into the water for fish health.
If used as a filter substance, a silicone removing resin should be
employed afterwards. |
| Diffused Air Aeration: |
A diffused air activated sludge plant takes air, compresses it, and
then discharges the air below the water surface of the aerator through
some type of air diffusion device. |
| Digester: |
A tank in which sludge is placed to allow decomposition by
microorganisms. Digestion may occur under anaerobic (most common) or
aerobic conditions. |
| Disinfection: |
The process designed to kill most microorganisms in wastewater,
including essentially all pathogenic (disease-causing) bacteria. There
are several ways to disinfect, with chlorine being the most frequently
used in water and wastewater treatment plants. |
| Distribution box: |
Serves to distribute the flow from the septic tank evenly to the
absorption field or seepage pits. It is important that each trench or
pit receive an equal amount of flow. This prevents overloading of one
part of the system. |
| Dissolved solids: |
Chemical substances either organic or inorganic that are dissolved
in a waste stream and constitute the residue when a sample is evaporated
to dryness. |
| Distributor: |
The rotating mechanism that distributes the wastewater evenly over
the surface of a trickling filter or other process unit. |
| DO: |
Dissolved Oxygen - a measure of the oxygen dissolved in water
expressed in milligrams per liter. |
| DOUR: |
Dissolved Oxygen Uptake Ratio. |
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| Ecology: |
The study of all aspects of how organisms interact with
each other and/or their environment |
| Ecosystem: |
Groupings of various organisms interacting with each other and their
environment. |
| E-coli: |
Escherichia coli - one of the non-pathogenic coliform organisms used
to indicate the presence of pathogenic bacteria in water. |
| Effluent: |
Wastewater or other liquid - raw (untreated), partially or
completely treated - flowing from a reservoir, basin, treatment process,
or treatment plant. |
| EGL: |
Energy grade line - a line that represents the elevation of energy
head in feet of water flowing in a pipe, conduit, or channel. |
| Electrolytic process: |
A process that causes the decomposition of a chemical compound by
the use of electricity. |
| Emulsion: |
A liquid mixture of two or more liquid substances not normally
dissolved in one another, one liquid held in suspension in the other. |
| Endogenous respiration: |
A reduced level of respiration (breathing) in which organisms break
down compounds within their own cells to produce the oxygen they need. |
| Enteric: |
Of intestinal origin, especially applied to wastes or bacteria. |
| Enzyme: |
Organic substances (proteins) produced by living organisms and act
as catalysts to speed up chemical changes. |
| Environmental resistance: |
All biotic and abiotic factors combining to limit explosion. |
| Equalizing basin: |
A holding basin in which variations in flow and composition of
liquid are averaged. Such basins are used to provide a flow of
reasonably uniform volume and composition to a treatment unit. Also
called a balancing reservoir. |
| Estuaries: |
Bodies of water which are located at the lower end of a river and
are subject to tidal fluctuations. |
| Eurythermal: |
Bodies of water which are located at the lower end of a river and
are subject to tidal fluctuations. |
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| Facultative anaerobe: |
A bacterium capable of growing under aerobic conditions
or anaerobic conditions in the presence of an inorganic ion ie. SO4,
NO3. |
| Facultative pond: |
The most common type of pond in current use. The upper portion
(supernatant) is aerobic, while the bottom layer is anaerobic. Algae
supply most of the oxygen to the supernatant. |
| Fermentation: |
A type of heterotrophic metabolism in which an organic compound
rather than oxygen is the terminal electron (or hydrogen) acceptor. Less
energy is generated from this incomplete form of glucose oxidation than
is generated by respiration, but the process supports anaerobic growth.
|
| Filamentous organisms: |
Organisms that grow in a thread or filamentous form. Common types
are Thiothrix, Actinomycetes, and Cyanobacteria (aka blue-green
algae). This is a common cause of sludge bulking in the activated sludge
process. Variously known as "pond scum", "blue-green algae", or "moss",
when it appears in a pond/lake, and confused with algae because it looks
a lot like algae. Cyanobacteria forms a symbiotic relationship with some
varieties of algae, making the combination very difficult to combat in
lakes and ponds. Filamentous organisms and Actinomycetes will naturally
stick to solid surfaces. Common types of Cyanobacteria are:
Oscillatoria, Anabaena, and Synechococcus. Other filament formers
include: Spirogyra, Cladophora, Rhizoclonium, Mougeotia, Zygnema and
Hydrodictyon. Nocardia is another filament former, which causes
foaming and interferes with flocculation in a waste treatment plant. |
| Filter aid: |
A chemical (usually a polymer) added to water to help remove fine
colloidal suspended solids. |
| Floating matter: |
Matter which passes through a 2000 micron sieve and separates by
flotation for an hour. |
| Floc: |
Clumps of bacteria and particulate impurities or coagulants that
have come together and formed a cluster. Found in aeration tanks and
secondary clarifiers. |
| Flocculation: |
The process of forming floc particles when a chemical coagulant or
flocculent such as alum or ferric chloride is added to the wastewater. |
| F: |
Food - represents BOD in the F/M ratio. Expressed in pounds. |
| FOG: |
Fats, Oils and Greases. A measure of the non-petroleum based fats in
waste treatment. |
| F/M: |
A ratio of the amount of food to the amount of organisms. Used to
control an activated sludge process. |
| Flow equalization system: |
A device or tank designed to hold back or store a portion of peak
flows for release during low-flow periods. |
| Food chain: |
Very simple pathway of nutrient flow. Ex. Carnivore > herbivore >
plant. |
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| Gasification: |
The conversion of soluble and suspended materials into
gas during anaerobic decomposition. In clarifiers the resulting gas
bubbles can become attached to the settled sludge and cause large clumps
of sludge to rise and float on the water surface. In anaerobic sludge
digesters, this gas is collected for fuel or disposed of using a waste
gas burner. |
| Generation time: |
The time required for a given population to double in size. This
time can be as short as 20 minutes or as long as a week. |
| Glyoxylate cycle: |
A modification of the Krebs cycle, which occurs in some bacteria.
Acetyl coenzyme A is generated directly from oxidation of fatty acids or
other lipid compounds. |
| Gram positive: |
Bacterial cells which retain the crystal violet stain during a
staining procedure. Most strains of bacilli are gram positive. |
| Gram negative: |
Bacteria cells which lose the crystal violet during the decolorizing
step and are then colored by the counterstain. Pseudomonas and
Thiobacillus are examples of gram negative strains. |
| Grit: |
The heavy material present in wastewater, such as sand coffee
grounds, eggshells, gravel and cinders. |
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| Halophilic or Halotolerant: |
Bacteria which thrive in a highly salt environment, up
to 25% NaCl. |
| Headworks: |
The facilities where wastewater enters a wastewater
treatment plant. The headworks may consist of bar screens, comminutors,
a wet well and pumps. |
| Heterotroph: |
A microorganism which uses organic matter for energy and growth. |
| HRT: |
Hours of Retention Time. |
| House Sewer: |
The pipeline connecting the house and drain and the septic tank. |
| Humus: |
The dark organic material in soils, produced by the decomposition of
soils. The matter that remains after the bulk of detritus has
beenconsumed (leaves, roots). Humus mixes with top layers of soil (rock
particles), supplies some of the nutrients needed by plants -increases
acidity of soil; inorganic nutrients more soluble under acidic
conditions, become more available, EX. wheat grows
best at pH 5.5-7.0. Humus modifies soil texture, creates loose, crumbly
texture, that allows water to soak in and nutrients retained; permits
air to be incorporated into soil. |
| Hydraulic loading: |
Hydraulic loading refers to the flows (MGD or m3/day) to a treatment
plant or treatment process. |
| Hydrogen sulfide gas: |
Hydrogen sulfide is a gas with a rotten egg odor. This gas is
produced under anaerobic conditions. Hydrogen sulfide is particularly
dangerous because it dulls your sense of smell so that you don't notice
it after you have been around it for a while and because the odor is not
noticeable in high concentrations. The gas is very poisonous to your
respiratory system, explosive, flammable, and colorless. |
| Hydrolysis: |
The process in which carbohydrates and starches are simplified into
organic soluble organics, usually by facultative anaerobes. |
| Hygroscopic: |
Absorbing or attracting moisture from the air. |
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| Incineration: |
The conversion of dewatered wastewater solids by
combustion (burning) to ash, carbon dioxide, and water vapor. |
| Infiltration: |
The seepage of groundwater into a sewer system, including service
connections. Seepage frequently occurs through defective or cracked
pipes, pipe joints, connections or manhole walls. |
| Influent: |
The liquid - raw (untreated) or partially treated - flowing into a
reservoir, basin, treatment process or treatment plant. |
| Inoculate: |
To introduce a seed culture into a system. |
| Inorganic waste: |
Waste material such as sand, salt, iron, calcium, and other mineral
materials which are only slightly affected by the action of organisms.
Inorganic wastes are chemical substances of mineral origin; whereas
organic wastes are chemical substances usually of animal or plant
origin. |
| Interface: |
The common boundary layer between two substances such as between
water and a solid (metal) or between water and a gas (air) or between a
liquid (water) and another liquid (oil). |
| Intraspecies: |
Within same species; Elk vs. Elk |
| Interspecies: |
Between two different species, such as tomato and weeds. |
| Ionization |
The process of adding electrons to, or removing electrons from,
atoms or molecules, thereby creating ions. High temperatures, electrical
discharges, and nuclear radiation can cause ionization. |
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| Kick net: |
500 micron white mesh net is designed to meet the
requirements of groups performing USEPA Rapid Bioassessment Protocols
for Benthic Invertebrates. (Benthic = bottom dwelling) |
| Krebs Cycle: |
The oxidative process in respiration by which pyruvate (via acetyl
coenzyme A) is completely decarboxylated to C02. The pathway yields 15
moles of ATP (150,000 calories). |
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| Liquefaction: |
The conversion of large solid particles of sludge into
very fine particles which either dissolve or remain suspended in
wastewater. |
| Log growth: |
A growth phase in which cell production is maximum. |
| Lysing: |
A disintegration or breakdown of cells which releases organic
matter. |
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| MacConkey Streak: |
Laboratory test for the presence of gram negative
bacteria. We use this test to detect contamination of Bacillus
products such as CF 1000, 1002, 4002 and som of the Enz-OdorŪ products. |
| Macronutrient: |
An element required in large proportion by plants and other life
forms for survival and growth. Macronutrients include Nitrogen (N),
Potassium (K), and Phosphorous (P). |
| Masking agent: |
Substance used to cover up or disguise unpleasant odors. Liquid
masking agents are dripped into wastewater, sprayed into the air, or
evaporated (using heat) with the unpleasant fumes or odors and then
discharged into the air by blowers to make an undesirable odor less
noticeable. |
| M: |
Microorganisms - small organisms which require a microscope to be
seen. M represents the SS in the mixed liquor and is part of the F/M
ratio. |
| MCRT: |
Mean Cell Retention Time - days. An expression of the average time
that a microorganism will spend in an activated sludge process. |
| Mechanical aeration: |
The use of machinery to mix air and water so that oxygen can be
absorbed into the water. Some examples are paddle wheels, mixers,
rotating brushes to agitate the surface of an aeration tank; pumps to
create fountains; and pumps to discharge water down a series of steps
forming falls or cascades. |
| Media: |
The material in the trickling filter on which slime accumulates and
organisms grow. As settled wastewater trickles over the media, organisms
in the slime remove certain types of wastes thereby partially treating
the wastewater. Also the material in a rotating biological contactor (RBC)
or in a gravity or pressure filter. |
| MEK: |
Methyl ethyl ketone. |
| Mercaptans: |
Compounds containing sulfur which have an extremely offensive
skunk-like odor. Also sometimes described as smelling like garlic or
onions. |
| Mesophilic bacteria: |
A group of bacteria that grow and thrive in a moderate temperature
range between 68 F (20 C) and 113 F (45 C). |
| Metabolism: |
All of the processes or chemical changes in an organism or a single
cell by which food is built up (anabolism) into living protoplasm and by
which protoplasm is broken down (catabolism) into simpler compounds with
the exchange of energy. |
| MGD: |
Million gallons daily - refers to the flow through a waste treatment
plant. |
| Mg/L: |
Milligrams per liter = ppm (parts per million) - expresses a measure
of the concentration by weight of a substance per unit volume. |
| Micron: |
A unit of length. One millionth of a meter or one thousandth of a
millimeter. One micron equals 0.00004 of an inch. |
| Micronutrient: |
An element required by plants and bacteria, in proportionately
smaller amounts, for survival and growth. Micronutrients include: Iron
(Fe), Managanese (MN), Zinc (Zn), Boron (B), and Molybdenum (Mo). |
| MIK: |
Methyl Isobutyl Ketone. |
| Miloginite: |
The name coined by a resident of Milwaukee, Wisconsin for "sewage
sludge", so he could scam people into buying sludge instead of paying to
dispose of it! When this ingredient is listed in a septic product, you
can be assured that the product is fraudulent! You don't use sludge to
get rid of sludge! |
| Molecule: |
The smallest division of a compound that still retains or exhibits
all the properties of the substance. |
| Monoculture: |
Aquaculture in which one species is grown. |
| Motile: |
Motile organisms exhibit or are capable of movement. |
| ML: |
Mixed Liquor - the combination of raw influent and returned
activated sludge.(no, not mixed drinks for human consumption) |
| MLSS: |
Mixed Liquor Suspended Solids - the volume of suspended solids (see
SS) in the mixed liquor (see ML) of an aeration tank. |
| MLVSS: |
Mixed Liquor Volatile Suspended Solids - the volume of organic
solids that can evaporate at relatively low temperatures (550 C) from
the mixed liquor of an aeration tank. This volatile portion is used as a
measure or indication of microorganisms present. Volatile substances can
also be partially removed by air stripping. |
| MPN index: |
Most Probable Number of coliform-group organisms per unit volume of
sample water. Expressed as a density or population of organisms per 100
mL of sample water |
| MSDS: |
Material Safety Data Sheet - a document that provides pertinent
information and a profile of a particular hazardous substance or
mixture. An MSDS is normally developed by the manufacturer or formulator
of the hazardous substance or mixture. The MSDS is required to be made
available to employees and operators whenever there is the likelihood of
the hazardous substance or mixture being introduced into the workplace.
Some manufacturers prepare MSDS for products that are NOT considered to
be hazardous to show that the product or substance is NOT hazardous. |
| Mutualism: |
Two species living together in a relationship in which both benefit
from the association. |
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| NH3N: |
Ammonia nitrogen. (The 3 should be subscripted, but I
have not figured out how to make this happen on the internet) |
| NPDES Permit: |
National Pollutant Discharge Elimination
System permit is the regulatory agency document issued by either
a federal or state agency which is designated to control all discharges
of pollutants from point sources into U.S. waterways. NPDES permits
regulate discharges into navigable waters from all point sources of
pollution, including industries, municipal wastewater treatment plants,
sanitary landfills, large agricultural feed lots and return irrigation
flows. |
| Nitrification: |
An aerobic process in which bacteria change the ammonia and organic
nitrogen in wastewater into oxidized nitrogen (usually nitrate). The
second-stage BOD is sometimes referred to as the "nitrification stage"
(first-stage BOD is called the "carbonaceous stage"). |
| Nitrifying bacteria: |
Bacteria that change the ammonia and organic nitrogen in wastewater
into oxidized nitrogen (usually nitrate). |
| Nitrogen fixation: |
Conversion of atmospheric nitrogen into organic nitrogen compounds
available to green plants; a process that can be carried out only by
certain strains of soil bacteria. |
| Nucleic acid: |
An organic acid consisting of joined nuceleotide complexes; the
principal tyes are deoxyribonucleic acid (DNA) and ribonucleic acid
(RNA). |
| Nutrients: |
Substances which are required to support living plants and
organisms. Major nutrients are carbon, hydrogen, oxygen, sulfur,
nitrogen and phosphorus. Nitrogen and phosphorus are difficult to remove
from wastewater by conventional treatment processes because they are
water soluble and tend to recycle. |
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| Obligate aerobe: |
Bacteria which require the presense of oxygen, such as
Pseudomonas flourescens. A few strains of this species are capable of
utilizing nitrate to allow anaerobic respiration. |
| Oil Retention Boom: |
A floating baffle used to contain and prevent the spread of floating
oil on a water surface. |
| Organic matter: |
All of the degradable organics. Living material containing carbon
compounds. Used as food by microorganisms. |
| Organic nitrogen: |
The nitrogen combined in organic molecules such as proteins, amines,
and amino acids. |
| ORP: |
Oxidation reduction potential - the degree of completion of a
chemical reaction by detecting the ratio of ions in the reduced form to
those in the oxidized form as a variation in electrical potential
measured by an ORP electrode assembly. |
| OSHA: |
The Williams-Steiger Occupational Safety and Health Act of 1970 (OSHA)
is a law designed to protect the health and safety of industrial workers
and treatment plant operators. It regulates the design, construction,
operation and maintenance of industrial plants and wastewater treatment
plants. The Act does not apply directly to municipalities, EXCEPT in
those states that have approved plans and have asserted jurisdiction
under Section 18 of the OSHA Act. Wastewater treatment plants have come
under stricter regulation in all phases of activity as a result of OSHA
standards, which also refers to the federal and state agencies which
administer OSHA. |
| Organic waste: |
Waste material which comes mainly from animal or plant sources.
Organic waste generally can be consumed by bacteria and other small
organisms. Inorganic wastes are chemical substances of mineral origin. |
| Organism: |
Any form of animal or plant life. |
| Oxidation: |
Combining elemental compounds with oxygen to form a new compound. A
part of the metabolic reaction. |
| Oxidizing bacteria: |
Any substance such as oxygen (O2) and chlorine (Cl2), that can
aaccept electrons. When oxygen or chlorine is added to wastewater,
organic substances are oxidized. These oxidized organic substances are
more stable and less likely to give off odors or to contain disease
bacteria. |
| Ozonation: |
The application of ozone to water, wastewater, or air, generally for
the purposes of disinfection or odor control. |
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| Parisitism: |
One organism living on or in another to obtain
nourishment, without provviding any benefit to the host organism. |
| Particulate: |
Free suspended solids. |
| Pathogenic organisms: |
Bacteria, viruses or cysts which cause disease (typhoid, cholera,
dysentery) in a host (such as a person). There are many types of
bacteria (non-pathogenic) which do NOT cause disease. Many beneficial
bacteria are found in wastewater treatment processes actively cleaning
up organic wastes. |
| PAH: |
Polycyclic Aromatic Hydrocarbons. (rarely used as abbreviation for
polyaluminum hydroxide) |
| PCB: |
Polychlorinated biphenyls. Aka polychloro-biphenyls. Difficult to
remediate chemical used in old-style transformers. Concentrated PCBs
used to be referred to as "1268". |
| Percolation: |
The movement or flow of water through soil or rocks |
| Peristaltic pump: |
A type of positive displacement pump |
| pH: |
pH is an expression of the intensity of the basic or acidic
condition of a liquid. Mathematically, pH is the logarithm (base 10) of
the reciprocal of the hydrogen ion concentration. The pH may range from
0 to 14, where 0 is most acidic, 14 most basic, and 7 is neutral.
Natural waters usually have a pH between 6.5 and 8.5. |
| Phenol: |
An organic compound that is an alcohol derivative of benzene. |
| Phototroph: |
A microorganism which gains energy from sunlight (radiant energy). |
| PIB: |
Product Information Bulletin. General information on a product. |
| Pin Floc: |
Excessive solids carryover. May occur from time to time as small
suspended sludge particles in the supernatant. There are two kinds: grey
-ashlike, inert, has low BOD - indicates old sludge; and brown, but a
portion neither settles nor rises, has high BOD - indicates young sludge |
| Predation: |
One species benefits at the expense of another. |
| ppm: |
Parts Per Million - the unit commonly used to designate the
concentration of a substance in a wastewater in terms of weight ie. one
pound per million pounds, etc. ppm is synonymous with the more commonly
used term mg/L (milligrams per liter). |
| Pollution: |
The impairment (reduction) of water quality by agriculture, domestic
or industrial wastes (including thermal and radioactive wastes) to such
a degree as to hinder any beneficial use of the water or render it
offensive to the senses of sight, taste, or smell or when sufficient
amounts of waste creates or poses a potential threat to human health or
the environment. |
| Polyculture: |
Fish farming in which 2 or more compatible or symbiotic species of
fish are grown together. Also known as Multiculture. |
| Polymer: |
A chemical formed by the union of many monomers (a molecule of low
molecular weight). Polymers are used with other chemical coagulants to
aid in binding small suspended particles to form larger chemical flocs
for easier removal from water. All polyelectrolytes are polymers, but
not all polymers are polyelectrolytes. |
| Potable water. |
Water that does not contain objectionable pollution, contamination,
minerals, or infective agents and is considered satisfactory for
drinking. |
| POWT: |
Publicly Owned Treatment Works, as opposed to an industrially owned
facility or pipe system. |
| Preliminary treatment: |
The removal of metal, rocks, rags, sand, eggshells, and similar
materials which may hinder the operation of a treatment plant.
Preliminary treatment is accomplished by using equipment such as racks,
bar screens, comminutors, and grit removal systems. |
| Pretreatment facility: |
Industrial wastewater treatment plant consisting of one or more
treatment devices designed to remove sufficient pollutants from
wastewaters to allow an industry to comply with effluent limits
established by the US EPA General and Categorical Pretreatment
Regulations or locally derived prohibited discharge requirements and
local effluent limits. Compliance with effluent limits allows for a
legal discharge to a POTW. |
| Primary treatment: |
A wastewater treatment process that takes place in a rectangular or
circular tank and allows those substances in wastewater that readily
settle or float to be separated from the water being treated. |
| Procaryotic organism: |
Microorganisms which do NOT have an organized nucleus surrounded by
a nuclear membrane. Bacteria and blue-green algae fit in this category. |
| Protozoa: |
A group of motile microscopic animals (usually single-celled and
aerobic) that sometimes cluster into colonies and often consume bacteria
as an energy source. |
| Psychrophilic bacteria: |
Bacteria whose optimum temperature range is between 0 and 20 C (32
to 68 C). |
| Putrefaction: |
Biological decomposition of organic matter with the production of
ill-smelling products associated with anaerobic conditions. |
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| Rack: |
Evenly spaced parallel metal bars or rods located in the
influent channel to remove rags, rocks, and cans from wastewater. |
| RAS: |
Return activated sludge - settled activated sludge that is collected
in the secondary clarifier and returned to the aeration basin to mix
with incoming raw settled wastewater. |
| RASVSS: |
Return Activated Sludge Volatile Suspended Solids. |
| RBC: |
Rotating biological contactor - an attached culture wastewater
treatment system |
| Reagent: |
A pure chemical substance that is used to make new products or is
used in chemical tests to measure, detect, or examine other substances. |
| Recycle: |
The use of water or wastewater within (internally) a facility before
it is discharged to a treatment system. |
| REDOX: |
Biological reductions/oxidations. These reactions usually require
enzymes to mediate the electron transfer. The sediment in the bottom of
a lake, sludge in a sewerage works or septic tank will have a very low
redox potential and will likely be devoid of any oxygen. This sludge or
waste water will have a very high concentration of reductive anaerobic
bacteria, indeed the bulk of the organic matter may in fact be bacteria.
As the concentration of oxygen increases the oxidation potential of the
water will increase. A low redox potential or small amount of oxygen is
toxic to anaerobic bacteria, therefore as the concentration of oxygen
and redox potential increases the bacterial population changes from
reductive anaerobic bacteria to oxidative aerobic bacteria. Measurement
of REDOX potential is also referred to as ORP. |
| Reducing agent: |
Any substance, such as the base metal (iron) or the sulfide ion that
will readily donate (give up) electrons. The opposite of an oxidizing
agent. |
| Refractory materials: |
Material difficult to remove entirely from wastewater such as
nutrients, color, taste, and odor-producing substances and some toxic
materials. |
| Respiration: |
The energy producing process of breathing, by which an organism
supplies its cells with oxygen and relieves itself of carbon dioxide. A
type of heterotrophic metabolism that uses oxygen in which 38 moles of
ATP are derived from the oxidation of 1 mole of glucose, yielding
380,000 cal. (An additional 308,000 cal is lost as heat.) |
| Rhizosphere: |
Soil surrounding plant roots. |
| R/O unit: |
Reverse Osmosis Unit for water purification in small aquariums and
miniature yard-ponds, utilizes a membrane under pressure to filter
dissolved solids and pollutants from the water. Two different filter
membranes can be used: the CTA (cellulose triacetate) membrane is less
expensive, but only works with chlorinated water and removes 50-70% of
nitrates, and the TFC membrane, which is more expensive, removes 95% of
nitrates, but is ruined by chlorine. R/O wastes water and a system that
cleans 100 gallons a day will cost from $400 to $600 with membrane
replacement adding to the cost. A unit that handles 140 gallons a day
will cost above $700.00. |
| RR: |
Respiration rate - the weight of oxygen utilized by the total weight
of MLSS in a given time. |
| Runoff: |
Water running down slopes rather than sinking in (again,result of
poor humus content) Ex. erosion due to deforestation |
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| Saprophytic: |
Bacteria that breakdown bodies of dead plants and
animals (non-living organic material), returning organic materials to
the food chain. Saprophytic bacteria are usually non-pathogenic, too.
|
| SAR: |
Sodium Adsorption Ratio - this ratio expresses the relative activity
of sodium ions in the exchange reactions with the soil. |
| SCFM: |
Cubic feet of air per minute at standard conditions of temperature,
pressure and humidity (0 , 14.7 psi and 50% relative humidity). |
| Secondary Treatment: |
A wastewater treatment process used to convert dissolved or
suspended materials into a form more readily separated from the water
being treated. Usually the process follows primary treatment by
sedimentation. The process commonly is a type of biological treatment
process followed by secondary clarifiers that allow the solids to settle
out from the water being treated. |
| Sedimentation: |
The process of subsidence and deposition of suspended matter from a
wastewater by gravity. |
| Seeding: |
Introduction of microorganisms into a biological oxidation unit to
minimize the time required to build a biological sludge. Also referred
to as inoculation with cultured organisms. |
| Seine net: |
A net designed to collect aquatic organisms inhabiting natural
waters from the shoreline to 3' depths is called a seine net. Most often
a plankton seine. |
| Septic: |
A condition produced by anaerobic bacteria. If severe, the
wastewater turns black, gives off foul odors, contains little or no
dissolved oxygen and creates a high oxygen demand. |
| Septicity: |
Septicity is the condition in which organic matter decomposes to
form foul-smelling products associated with the absence of free oxygen.
If severe, the wastewater turns black, gives off foul-odors, contains
little or no dissolved oxygen and creates a heavy oxygen demand. |
| Septic Tank: |
Untreated liquid household wastes (sewage) will quickly clog your
absorption field if not properly treated. The septic tank is a holding
tank in which this treatment can take place. When sewage enters the
septic tank, the heavy solids settle to the bottom of the tank; the
lighter solids, fats and greases partially decompose and rise to the
surface and form a layer of scum. The solids that have settled to the
bottom are attacked by bacteria and form sludge. |
| Settleable solids: |
Those solids in suspension which will pass through a 2000 micron
sieve and settle in one hour under the influence of gravity. |
| Sewage: |
The used water and water-carried solids from homes that flow in
sewers to a wastewater treatment plant. The preferred term is
wastewater. |
| Shock load: |
The arrival at a plant of a waste which is toxic to organisms in
sufficient quantity or strength to cause operating problems. Possible
problems include odors and sloughing off of the growth or slime on a
trickling-filter media. Organic or hydraulic overloads also can cause a
shock load. |
| Sloughings: |
Trickling-filter slimes that have been washed off the filter media.
They are generally quite high in BOD and will lower effluent quality
unless removed. |
| Sludge: |
The settleable solids separated from liquids during processing; the
deposits of foreign materials on the bottoms of streams or other bodies
of water. |
| Sludge age: |
A measure of the length of time a particle of suspended solids has
been retained in the activated sludge process. |
| Slugs: |
Intermittent releases or discharges of industrial wastes. |
| Soluble: |
Matter or compounds capable of dissolving into a solution. |
| Soluble BOD: |
Soluble BOD is the BOD of water that has been filtered in the
standard suspended solids test. |
| Solution: |
A liquid mixture of dissolved substances, displaying no phase
separation. |
| Specific gravity: |
Weight of a particle, substance or chemical solution in relation to
an equal volume of water. |
| Spec. Sheet: |
Specification Sheet. Detailed information of a product including,
tests, color, odor, specific gravity, bacterial strains, other major
ingredients, etc. |
| SS: |
Suspended solids - Solids in suspension in water which can be
filtered out on a lab filter. |
| Stabilize: |
To convert to a form that resists change. Organic material is
stabilized by bacteria which convert the material to gases and other
relatively inert substances. Stabilized organic material generally will
not give off obnoxious odors. |
| Stasis: |
Stagnation or inactivity of the life processes within organisms. |
| Sterilization: |
The removal or destruction of all living microorganisms, including
pathogenic and other bacteria, vegetative forms and spores. |
| Storm sewer: |
A separate pipe, conduit or open channel (sewer) that carries runoff
from storms, surface drainage and street wash, but does not include
domestic and industrial wastes. Storm sewers are often the recipients of
hazardous or toxic substances due to the illegal dumping or hazardous
wastes or spills created by accidents involving vehicles and trains
transporting these substances. |
| STP test: |
Laboratory test for nitrifiers. For CF1100, 7110, 1200 & 1400 to be
within specifications, this test must show positive within 7 days. |
| STP: |
Standard Temperature (25 C) and Pressure (300 mm Mercury). |
| Substrate: |
The base on which an organism lives. The soil is the substrate of
most seed plants where rocks, soil, water, or other tissues are
substrates for other organisms. |
| Supernatant: |
Liquid removed from a tank once the solids have
settled.
Supernatant commonly refers to the liquid between the sludge on the
bottom and the scum on the surface of an anaerobic digester. This liquid
is usually returned to the influent wet well or to the primary
clarifier. |
| Surfactant: |
Surface-active agent. The active age nt in detergents that possesses
a high cleaning ability. Used in a spray solution to improve its
sticking and wetting properties when applied to plants, algae, or
petroleum. |
| Synthesis: |
Breaking down organic compounds and converting the degradation
products into new cell growth. An energy using process. |
| SV: |
Sludge volume - a settling test using a two liter settleometer to
measure sludge quality expressed in percent and related to time, ie. 80%
in five minutes or 30% in 30 minutes. Also used to determine the rate of
settling. |
| SVI: |
Sludge volume index - a settling test used to measure sludge
quality. |
| SVR: |
The volume of sludge blanket divided by the daily volume of sludge
pumped from the thickener. |
| SV30: |
The value obtained in a 30 minute settleometer test. |
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| Taxonomy: |
The classification, nomenclature, and laboratory
identification of organisms (Do not confuse with taxidermy - stuffing
dead animals) |
| TDS: |
Total Dissolved Solids is commonly estimated from the electrical
conductivity of the water. Pure water is a poor conductor of
electricity. Impurities dissolved in the water cause an increase in the
ability of the water to conduct electricity. Conductivity, usually
expressed in units of microsimens, formerly micromhos or in mg/l, thus
becomes an indirect measure of the level of impurities in the water. |
| TOC: |
Total organic carbon - a measure of the amount of organic carbon in
water. |
| TOD: |
Another method of measuring organic matter in wastewater involves
the oxidation of the sample to stable end products in a
platinum-catalyzed combustion chamber at 900 degrees C. Total oxygen
demand is determined by measuring the oxygen content of the inert
carrier gas, nitrogen. TOD measurements are becoming more popular
because of their quickness in determining what is entering the plant and
how the plant is responding. Analysis time is approximately 5 minutes.
The results obtained generally will be equivalent to those obtained
in the COD test. |
| Thermophilic bacteria: |
Hot temperature bacteria. a group of bacteria that grow and thrive
in temperatures above 113 F (45 C), such as Bacillus licheniformis.
The optimum temperature range for these bacteria in anaerobic
decomposition is 120 F (49 C) to 135 F (57 C). |
| Toxic: |
A substance which is poisonous to a living organism. |
| Toxicity: |
The relative degree of being poisonous or toxic. A condition which
may exist in wastes and will inhibit or destroy the growth or function
of certain organisms. |
| Transpiration: |
The process by which water vapor is released to the atmosphere by
living plants, a process similar to people sweating. |
| Trickling filter: |
An attached culture wastewater treatment system. A large tank
generally filled with rock or rings (see Bio-Tower). Wastewater is
sprayed over the top of the media, providing the opportunity for the
formation of slimes or biomass to remove wastes from the wastewater,
through revolving arms which have spray nozzles. Water is pumped from
the bottom of a trickle filter to a secondary clarifier. |
| TSS: |
Total suspended solids. |
| Turbidity: |
The amount of suspended matter in wastewater, obtained by measuring
its light scattering ability. |
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| Unicellular: |
Single celled organism, such as bacteria. |
| Upset: |
An upset digester does not decompose organic matter properly. The
digester is characterized by low gas production, high volatile
acid/alkalinity relationship, and poor liquid-solids separation. A
digester in an upset condition is sometimes called a "sour" or "stuck"
digester. |
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| Vector: |
An insect or other organism capable of transmitting
germs or other agents of disease. |
| Vegetative: |
Actually growing state. |
| Volatile: |
A volatile substance is one that is capable of being evaporated or
changed to a vapor at a relatively low temperature. Volatile substances
also can be partially removed by air stripping. |
| VS/L: |
Measure of volatile solids, usually expressed as g VS/L/day = grams
volatile solids per liter per day. |
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| WAS: |
Waste activated sludge, mg/L. The
excess growth of microorganisms which must be removed from the process
to keep the biological system in balance. |
| Wastewater: |
The used water and solids from a community that
flow to a treatment plant. Storm water, surface water, and groundwater
infiltration also may be included in the wastewater that enters a
wastewater treatment plant. The term "sewage" usually refers to
household wastes, but this word is being replaced by the term
"wastewater". |
| Weir: |
A wall or plate placed in an open channel and used
to measure the flow of water. |
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| Zoogleal film: |
A complex population of organisms that
form a "slime growth" on a trickling-filter media and break down the
organic matter in wastewater. |
| Zoogleal mass: |
Jelly-like masses of bacteria found in both the
trickling filter and activated sludge processes. |
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