General wastewater.txt

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General wastewater.txt
2012-09-22 22:18:26
DNR general wastewater

General Wastewater study guide.
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  1. Manhole
    structure that provides access to sewer system. usually round opening an iron lid
  2. wet well
    a collection area for wastewater. wastewater is then pumped from wet wells. are commonly found in list stations or at the head works of wastewater treatment plant
  3. microorganism
    and living organism too small to be seen with the naked eye but visible under microscope such as bacteria viruses fungi and protozoa
  4. sidestream
    A flow generated within the plant, that is then recycled back through the plant
  5. influent
    wastewater entering a treatment plant raw sewage
  6. effluent
    treated wastewater discharge from sewer plant into enviroment
  7. BOD biochemical oxygen demand
    A test that measures the organic strength of a sample by measuring the amount of oxygen consumed
  8. TSS total suspended solids
    a test that measures the total amount of solid suspended in a sample
  9. pH
    a measure of acidity and alkalinity of a sample on a scale of 0 to 14 acidic to alkaline ph 7 is neutral
  10. DO dissolved oxygen
    a measure of the amount of oxygen dissolved in water
  11. gpm gallons per minute
    a common measurements of wastewater flow expressed as a number of gallons following each minute
  12. gpd gallons per day
    a common measurements of waste water flow express as a number of gallons following each day
  13. MGD
    measurements of waste water flow in the treatment plant expressed as millions of gallons of wastewater flowing each day
  14. mg/L milligrams per liter
    the concentration of substance in a liquid expressed as a weight in milligrams per liter of volume milligrams per liter is the same as parts per million 1mg/L=1 ppm
  15. composite sample
    a sample prepared by combining a number of grab samples typically over 24 hour.
  16. grab samples
    a single sample taken at a particular time and place is representative of current conditions
  17. Weir
    A weir is a level control structure used to provide uniform flow
  18. Flume
    • a restriction in the open channel used to measure flow
  19. septage
    A high strength waste pumped out of septic tanks sometimes disposed at WWTPs
  20. HRT hydraulic retention time
    the period Of time that wastewater remains in the tank this term is also known as the detension time
  21. l/l inflow infiltration
    • any unwanted clearwater that leads into collection system generally it consist of groundwater rain water or snow melts
  22. sanitary sewer or collection system
    An under ground pipe system used to convey wastewater treatment plant
  23. storm sewer
    an underground pipe system that collect rain water from street and conveys it to place other than the waste water treatment plant
  24. combined sewer
    • pipe conveyance that carries both wastewater in storm water in a single pipe. during dry weather conditions- discharges to the waste water treatment plant. during wet weather condition discharge is directly to a water body. now's the extra wet weather volume is stored and took me returned to the
    • wastewater treatment plant
  25. lift station
    an underground chamber with pumps that is used to elevate wastewater to a higher grade. Lift stations are located within a collection system
  26. aerobic (oxic) [02]
    a condition in which 3 inches of blood oxygen is available in aqueous environment
  27. anaerobic ( septic) [0]
    a condition in which free dissolved in combined oxygen is unavailable and aqueous environment
  28. treatment process
    means a physical biological or chemical action that is applied to waste water to remove or reduce pollutants
  29. aeration basin
    a tank in which wastewater is a rated to achieve biological treatments
  30. screenings
    the material in wastewater that is removed on screens at the head works of the treatment plant such as sticks stones plastics and personal hygiene products
  31. Grit
    the fine abrasive particles removed from wastewater such is sand an egg shells
  32. Headworks
    the beginning or head of a treatment plant where influence flow is measured & sampled and where preliminary treatment occurs
  33. Tertiary Treatment
    a treatment process that uses physical chemical biological processes to remove suspended solids and nutrients in wastewater
  34. secondary treatment
    treatment process that uses biological processes utilizing bacteria to remove pollutants
  35. primary treatment
    a treatment process that usually consist of clarification by solid/liquid separation that removes a substantial amount a suspended and floating matter
  36. Preliminary treatment
    treatment process consisting of screening and grit removal before the waste water flows into other treatment processes
  37. treatment unit
    individual structure or equipment within a sewage or wastewater treatment facility that is a treatment process
  38. clarifier
    a circular a rectangular tank use to remove floatable and several solids in wastewater
  39. disinfection
    a process used to destroy most pathogens in the effluent to a safe level. disinfection does not destroy all microorganisms
  40. biosolids
    the nutrient rich organic byproduct of a municipal wastewater treatment plant that is used as fertilizer
  41. process control
    the tools and methods used to optimize treatment plant operation
  42. return activated sludge (RAS)
    this settled activated sludge (biomass) that is collected in a secondary clarifier and returned to the secondary treatment process to mix with incoming wastewater. this returned a concentrated population of microorganisms back into the aeration basin
  43. waste activated sludge (WAS)
    the activated sludge ( excessive biomass or cell mass) removed from the secondary treatment process. For most treatment plants, this will be a portion of the return activated sludge flow stream
  44. confined space
    a space that is large enough for operator to enter & preform assigned work it has limited or restricted means for entry and exit and not designed for continuous occupancy
  45. pathogens
    infectious microorganisms in wastewater that pose a health risk
  46. wisconsin pollutant discharge elimination system (WPDES)
    a wisconsin pollution discharge in the nation system permit is issued to wastewater facility owners which contains effluent and biosolids/sludge limitations, conditions and reporting requirements
  47. early historical methods of dealing with waste water
    Waste was basically deposited on land surfaces, gutters ditches. produced illnesses, diseases,odor, unsightly ness. Rain was counted on to wash away. Then pits where used and then waste water & storm water added but problem still remained of making safe for environment.
  48. 2 reasons for treating wastewater
    • 1. protect human health by destroying pathogens
    • 2 to protect the environment by removing pollutants
  49. sources of wastewater in a community
    • wastewater from household industrial and commercial services
    • clearwater etc. rain snow on ground water from inflow infiltration
  50. define common sources of inflow/infiltration
    • defined as unwanted Clearwater getting into the collection system
    • classified by how fast it gets into collection system and determined by weather and ground conditions
  51. clear water sources
    • roof leaders connected to sanitary sewer,
    • storm sanitary crossovers,
    • low lying man holes,
    • uncapped lateral connections,
    • Sump pumps & foundation drains,
    • Cracks in sanitary sewer,
    • Manhole cracks & defects,
    • Cracks leaks on building sewer
  52. Effects of inflow/infiltration
    • Can increase capacity flow causing surcharging, basement backups, sewer overflows.
    • High flow entering treatment plant can lead to waste water pumping and treatment problems.
  53. components of a sanitary sewer collection system
    • private building lateral swer
    • mainline to work
    • forced Main
    • lift pump station
    • inverted siphon
    • manhole
  54. O&M
    operation and maintenance
  55. O&M primary activities
    • cleaning
    • Root removal,
    • Televising,
    • Flow monitoring,
    • Smoke testing,
    • Manhole inspection,
    • Lift station maintenance,
    • Manhole rehabilitation
    • Mainline rehabitation,
    • private sewer inspections,
    • private sewer inflow/ infiltration removal,
    • Fat, oil, & grease control program
  56. characteristics of influent domestic waste water
    • sewage is 99 percent
    • Gray in color
    • earthy musty odor
  57. typical influent wastewater concentrations
    • BOD 250 mg/l
    • TSS 300 mg/l
    • Total nitrogen 40 mg/l
    • Ammonia 25 mg/l
    • Total phosphorous 9 mg/l
    • Fats, oil, grease (FOG) 100 mg/l
    • pH 6.5-8.0 mg/l
  58. disinfection process purpose
    treat wastewater to kill and thus reduce the discharge of water borne pathogens are organisms that cause illness
  59. why do you disinfect wastewater
    protect public health as related to surface drinking water supplies and recreational use of downstream areas
  60. how is disinfection achieved
    • chlorination tanks or
    • ultraviolet radiation units
  61. seasonal disinfection
    provides just infection during the month recreational activities are using downstream serious
  62. define pond and lagoon the systems
    • Earthen basins with liners to prevent leakage,
    • Classified as secondary biological treatment,
    • Typically used for BOD & TSS removal when limits are 30mg/l,
    • Flow often goes though more than 1 pond in series,
    • Size provides long detention time for bacteria to break down the wastes,
    • Mostly used in sm communities when land is available.
  63. stabilization pond system
    • large non,aerated and normally less than 10 feet deep.
    • algea growingin ponds provides most of oxygen to bacteria to remove pollutants.
    • solids settle to bottom of pond and are further stabilize by bacteria.
  64. aerated lagoon system
    • normally more then 10 feet deep.
    • aeration provided by diffusers or surface aerators.
    • aeration improves removal efficiency.
    • followed by non aerated lagoon to allow settling a suspended solids before discharge
  65. types of waste water pumps
    • centrifugal
    • submersible
    • positive displacement piston pump rotary lobe pump
    • peristaltic pump
    • progressive cavity pump
    • air lift pump
    • diaphragm pump
    • trash pump
    • multi turn valves (gate, globe, diaphragm, pinch)
    • quarter turn valve ( needle, plug, ball, butterfly)
    • self actuated valve ( check, relief)
  66. Types of values
    • multi turn valves (gate, globe, diaphragm, pinch)
    • quarter turn valve ( needle, plug, ball, butterfly)
    • self actuated valve ( check, relief)
  67. centrifugal pump
    • Pump with impeller that rotates in a casting to pump a large volume of liquid through a pipe.
    • Most commonly used wastewater pump.
    • Used mostly for raw wastewater.
    • Lift stations, recirculation flows,
    • for return activated sludge,
    • waste activated sludge
    • and final effluent pump Inc
  68. parts of centrifugal pump
    • flow in
    • casing
    • vane
    • Shaft
    • Packing
    • Stuffing box
    • Impeller
    • Discharge nozzle
    • flow out
  69. submersible pump
    • the pump and motor combination are submerged in the liquid being pumped.
    • they are a type of centrifugal pump often used for lift stations and wet wells
  70. parts of a submersible pump
    • flow in,
    • impeller,
    • upper and lower shaft seals,
    • lower bearing
    • rotary assembly,
    • stator,
    • Upper bearing,
    • power cable,
    • Volute,
    • Flow out
  71. positive displacement piston pump
    • operate using a piston in a reciprocating motion to pump fluids.
    • Similar to piston in automotive engine.
    • commonly used for pumping sludges
  72. parts of positive displacement piston pump
    • suction,
    • suction check valve,
    • stuffing box,
    • packing,
    • connection rod,
    • eccentric,
    • oiler,
    • Plunger,
    • Packing gland,
    • Sample value,y
    • discharge check ball chamber yoke,
    • air chamber,
    • discharge
  73. rotary lobe pump uses
    Both sewage and sludge
  74. positive displacement piston pump uses
    Commonly used for pumping sludge
  75. submersible pump uses
    often used for lift stations and wet wells
  76. Centrifugal pump uses
    Mostly commonly used for raw sewage
  77. Rotary lobe pump
    • Used to pump sewage & sludge.
    • They are self priming, value les, partitive displacement pumps.
    • 2 synchronized rotors rotating against each other create chambers between the lobes & pump casting.
    • At the suction side ther open chamber fills with the sewage or sludge then is displaced in the direction of the volume flow into the discharge side.
    • When not operating the rotors align and form a seal.
  78. Peristaltic pump
    A small positive displacement pump commonly used for sampling and chemical addition.
  79. Peristaltic pump uses
    commonly used for sampling and chemical addition.
  80. Peristaltic pump parts
    • Tubing clamps,
    • Housing
    • Roller
    • Tubing
  81. Progressive cavity pump
    • A fixed flow rate that turns a corkscrew shaped rotor inside a flexible tiber stator to transfer sludges.
    • Offer long life & reliable service ass long as they don't run dry or with excessive grit
  82. Airlift pump uses
    Mostly used in small activated sludge plants to return and waste sludge from the system
  83. Airlift pumps
    • Mostly used in small activated sludge plants to return and waste sludge from the system.
    • Operate on principle of water/air displacement.
    • Prone to plugging, especially at low return rates.operators should closely monitor often to ensure sludge its being returned at all times.
  84. Airlift pump parts
    • Air supply
    • Liquid supply,
    • Air outlet,
    • Fluid intake,
    • Riser,
    • Pump outlet
  85. Diaphragm pump uses
    • Adding chemicals or polymers
    • Larger diaphragm pumps are used from pumping sludge
  86. Diaphragm pump
    • A type of positive displacement pump.
    • They differ from other positive displacement pumps is they are protected from material being pumped.
    • Adding chemicals or polymers large diaphragm pumps are used from pumping sludge
  87. Parts diaphragm pump
    • Pulsation chamber,
    • Inlet check value,
    • Inlet,
    • Pump diaphragm,
    • rocker arm spring,
    • Camshaft,
    • Outlet,
    • Outlet check value
    • Diaphragm spring,
    • Vent hole,
    • Oil seal,
    • Pull rod
  88. Trash pumps uses
    Used fire moving large volumes of wastewater quickly such as dewatering, bypassing, emptying treatment plants.
  89. Trash pump
    Usually gas or diesel operated positive displacement portable pump with a suction hose & a discharge hose. They are non clogging (can handle a 3-4 inch perfect without clogging. Used for moving large volumes of wastewater quickly such as dewatering, bypassing, emptying treatment plants.
  90. Trash pump parts
    • Pump casing,
    • Discharge,
    • Check value,
    • Shaft sleeve,
    • Housing.
    • Impellers and volutes
  91. What is a value?
    • Devices placed in piping systems to stop, regulate, divert, or change flow.
    • Proper procedure for opening & closing values must be ffollowed to prevent personal injury and reuben damage.
  92. Types of multi use values
    • Gate,
    • Globe,
    • Diaphragm,
    • Pinch
  93. Gate valve
    • Multi turn
    • General service valve
    • Mostly used for full flow or no flow application
    • Its closed using a gate or plate that slides the valve down to block the flow.
  94. Diaphragm valve
    • Multi turn
    • Often used for corrosive wastewater
    • Closed bry a flexible diaphragm that its attached to a compresser. The diaphragm is lowered by the valve stem onto a weir, sealings, and shutting off the flow.
  95. Pinch valve
    • Multi turn
    • Often used on sludge lines out wastewater with a high any of suspended solids.
    • Closed by a flexible member in a value that can be pinched close to shut off flow
  96. Quarter turn valve
    • Needle
    • Plug
    • Ball
    • Butterfly

  97. Needle valve
    • Quarter turn valve
    • used to regulate flow in small lines, such as air lines or fuel lines.
    • A rod with a cone shaped tip is taised and lowered relative to a seat, thus creating a certain size opening for which flow to pass.
  98. Plug valve
    • Quarter turn valve
    • used for on-off and some throttling application.
    • it is clsed by turning a cylindrical or tappered plug with a hole in the center.
    • When open to allow ful flowthe hole line up directly with the flow path.
    • a quarter turn in each direction blocks the flow.
  99. Ball valve
    • Quarter turn valve
    • used for on-off and some throttling applications
    • it operated simily to a plug value but uses a rotating ball with a hole in the center. 
    • when open to allow full flow, the hole lines up directly with the flow path
    • When closed the ball is rotated 90 degress to block flow
  100. Butterfly Valve
    • used for on-off and Good for throttling application.
    • Regulates flow by turing a circular disk or vane. 
    • When open to allow for full flow the vane is directly parallel to the flow. 
    • when closed the vane is perpendicular to block the flow
  101. List self-actuated valves
    • Check valve
    • relief valve
  102. Check Valve
    • Self-actuated
    • used to allow flow in one direction
    • it operates by flow in the desired direction opening the valve while flow backwards forces it closed.
  103. Relief valve
    • self-actuating
    • used to  prevent excessive pressure
    • operates by releasing pressure if the safety limit is exceeded.
    • once the pressure drops to preset level the valve closes
  104. function of Blower in aeration equipment in a wastewater treatment plant
    provide the air that is pumped though diffusers
  105. discribe Mechanical aerators
    most comman utilize paddles or discs and spray or turbine mechanisms. By  aggitating the wastewater, air from enviroment is introduced.
  106. List aeration equipment in a wastewater treatment plant
    • Blowers- provide the air that is pumped though diffusers
    •      Centrifugal
    •      Positive displacement
    • Diffusers-
    •       fine bubble
    •       Course bubble
    • Mechanical aerators-most comman utilize paddles or discs and spray or turbine mechanisms. By  aggitating the wastewater, air from enviroment is introduced.
  107. List type of blowers in wastewater treatment plant
    • Centrifugal
    • Positive displacement
  108. Describe Centrifugal blower
    a blower consisting of an impeller fixed on a rotating shaft and enclosed in a casing having an inlet and discharge valve
  109. Discribe Positive Displacement Blower
    (PD) blower forces air to move by trapping a fixed amount, then displacing that trapped volume into the discharge pipe
  110. List type of Diffusers in a wastewater treatment plant
    • Fine bubble 
    • Course bubble
  111. Discribe Fine Bubble Diffuser
    • A device though which air is pumped and divided into very small bubbles that are used to introduce and dissolve oxygen into the liquid.
    • Fine bubble diffusers are normally disks or tubes that use membranes or ceramic materials to creat the bubbles and gentle mixing action
  112. Discribe Course Bubble Diffusers
    • A device though which is is pumped and divided into large bubbles that are transferred and dissolved into that liquid.
    • Course bubble diffusers normally discharge air at a high rate and are installled to induce a spriral or cross roll mixing pattern
  113. Describe the Types of Instrumentation and Controls
    • Process Probes and Analyzers
    • Supervisory Control and Data Acquisition (SCADA)
    • Programmable Logic Controller (PLC)
    • Flow Meters
    • Alarms
  114. Describe
    Process Probes and Analyzers
    Process probes, such as pH, total suspended solids (TSS),dissolved oxygen, turbidity, and temperature, are used thoughout the treatment plant. usually are wire to an analyzer that send data to a computer.
  115. Types of Process probes
    • pH,
    • total suspended solids (TSS),
    • dissolved oxygen,
    • turbidity,
    • temperature,
  116. Supervisory Control and Data Acquisition (SCADA)
    • SCADA is a computer program that is used soley for gathering the  plants operation data.
    • The program shows different parts of the plant and what is happening in real time.
    • An operator can see flows, dissolved oxygen levels,
    • blowers, pumps, tank levels, probe readings, and operatrional data. 
    • The data is stored within the program.
  117. example of info collected by SCADA
    flows, dissolved oxygen levels,blowers, pumps, tank levels, probe readings, and operatrional data.
  118. Programmable Logic Controller (PLC)
    • A PLC programmable electronis device that has inputs and outputs and is usually found in a control panel.
    • For example a PLC could turn a pump on and off, controlling the liquid level of a tank.
    • An operator would program the PLC with set points to dfine the levels that the pump turns on and off.
  119. example of flow meter measurements
    • influent,
    • effluent,
    • recycle streams,
    • sludge pumping,
    • septic stations,
    • lift stations,
    • chemical feed systems.
  120. Flow Meters
    • are used to measure the flow of liquids.
    • Some areas of measurement include: influent, effluent, recycle streams, sludge pumping, septic stations, fift stations, and chemical feed systems.
    • Usually wired to a SCADA system ath displays and stores flow data.
  121. Example of alarm warnings
    • high or low water level,
    • high or low dissolved oxygen level in the aeration process,
    • a malfunctioning pump,
    • a high temperature reading on a pump,
    • a problem at a lift station
    • or many other things.
  122. Alarms
    • Alarms notify operators of operation problems and emergencies.
    • Alarms could be during the working day or programmed to notif operators after hours.
    • An alarm could be high or low water level, high or low dissolved oxygen level in the aeration process, a malfunctioning pump, a high temperature reading on a pump, a problem att a lift station or many other things.
  123. why is it important to have a WWTP preventative maintenance program?
    • A. minimze unanticipated breakdowns or erergency maintenance
    • B.maximize operational consistent preformance
    • C. long-term cost saving
    • D. prevent violations
    • E energy effiecienties
  124. Describe a preventative maintence system
    • 1. inventory and label all equipent
    • 2. use O&M anuals for preventative maintenance tasks & frequenties
    • 3. Establish a preventative maintenance record keeping for maintenance
    • 4. establish a followup system to ensure maintenance is preformed
    • 5. have a spare parts inventory
  125. how do you prevent grease & grit build-up in a lift station wetwells
    • control grease and grit at its source,having stringent pretreatment requirements in the sewer ordinance and through a grease control program.
    • Monitor commericial & industrial sources to ensure good maintenance is preformed on grease traps, oil separartors, and any solids removal system.
  126. why do we lubricate equipment
    • one of the most important  preventative maintenance tasks at a wastewater treatment plant.
    • THe O&M manual specifies the type of lubricants and the frequencies of lubricaiton for  each piece of equipment.
  127. list comman critical maintenance tasks
    • a. lubrication
    • b. amperage checks
    • c. packing if leaking
    • d. flushing water seals
    • e. check for clogging.
    • Follow the O&M manual for all specific maintenance tasks
  128. List comman critical maintenance tasks for Valves
    • a. exercise
    • b. check for clogs (check valve)
    • Follow the O&M manual for all specific maintenance tasks for valves
  129. lict comman critical maintenance tasks for  motors
    • a. grease
    • b. temperature check
    • c. amperage check
    • d. inspect for noise and vibration
    • Follow the O&M manual for all specific maintenance tasks
  130. List the informational content of an WWTP O&M manual.
    The WIS DNR requires the following topics 
    • a. general information
    • b staffing
    • c. record systems
    • d. laboratory
    • e. safety 
    • f. securtiy & emergencies
    • g. Utilities & electrical systems
    • h. appendices
    • i. process description, operation and control (liquids & solids)
    • j. sludge management
    • k. maintenance
    • l. recommended reference materials ( manuals, books, codes)
  131. what is the purpose of biosolids/sludge thickening?
    to further concentrate and thicken solids settled & wasted from treatment palant propesses.
  132. what is the range mg/l for suspended solids
    solids form primary and secondary anc range form 1,000 to 10,000 mg/l
  133. thicken sludge range in mg/l
    • 10,000 to 30,000 mg/l 
    • allows for further handleing and processing
  134. what is the purpose of biosolids/sludge
    is to reduce the pathogens (fecal coliform) in the sludge and the attration of vectors (flies, mosquitos, vermin,birds, etc.) that attract diseases. 
  135. waht is sludge stabilization 
    treatment of biosolids/sludge
  136. What must happen before sludge can be landspread?
    must meat Wis DNR established pathogen control and vector attraction reduction critria list WPDES permit
  137. sludge treatment most commanly consists of ________
    aerobic or anaerobic digeters
  138. purpose of digesters
    digestors utilize bacteria in the treatment of the sludge
  139. explain aerobic digesters
    • utilizes microorganisms and oxygen to diget the remaining organic material in wasted sludge from the primary or secondary treatment process.
    • the detenion time is a aerobic is sufficiently ling to allow for mot oforganic material to be comsumed rulting in stablized sludge.
    • Similar to activated sludge except well digested, stabulized sludge in the tanks is thicker and darker
  140. explain anaerobic digester
    • utilizes microorgainisms without oxygen to gigeswt the remiaing orgain material in wasted sludge from the primary and secondary treatment process.
    • anaerobic digesters are heated and covered.
    • the o\process generats methane gas, that can be recovered and used as an energy source in the treatment plant.