Wastewater Treatment Engineering Environ Engineering Course Sequence Thermo

Wastewater Treatment Engineering

Environ. Engineering Course Sequence Thermo CE 3501 Fluids CE 4506 Regs, P 2, 3 CE 4504 Air Quality CE 4620 Open Channel Flow GE 3850 Geohydrol. P-Chem CE 3502 CE 3620 Water Resources CE 4501 Env. Chem ce 4505 Surf. Water CE 4508, 4507, 4509 Drinking & Waste. Water CE 4630 Hydraulic structures BL 4451 Limnology CE 5508: Biogeochem. , CE 5504: Surf. Water Qual. Modeling FW 4220 Wetlands

Historical Background Public Health Investigation of an outbreak of cholera in London in 1854 provided one of the first links between sewage disposal, drinking water supply and waterborne disease. Environmental Protection A 1920 s, study of the East and Fox Rivers in Green Bay was commissioned because workers in downtown could not open windows in summer due to the stench. Environmental problems plague this system to this day.

Nature of Wastewater What’s in wastewater? > human feces and urine > food from sinks > soaps and other cleaning agents > runoff from streets and lawns > industrial discharges

Nature of Wastewater … and water … lots of it! > Urinal - 1 gallon per flush – 0. 4 gal/flush > Toilet - 4 gallons per flush – 2 gal/flush > Shower - 20 gallons per use > Overall - 55 gal/person/day

Nature of Wastewater So what’s the problem?

Levels of Treatment

Regulatory Basis Clean Water Act of 1972 (since amended) • Technology-based standards (2°) • Water quality-based standards • Fishable-swimmable • NPDES (permitting system) • TMDLs (maximum daily loads)

Scope of Application On-Site Rural - Municipal Urban - Municipal Industrial

Portage Lake Wastewater Treatment Plant RAS 2° Clarifier 1° Clarifier Flow Equalization Fe added Aeration Tank 1° Clarifier 2° Clarifier RAS Grit Chamber UV Disinfection WAS Recycle Bar Screens 2 nd Stage Anaerobic Digester Supernatant Lift Station Land Application Sludge Storage Filter Press Polymer Added 1 st Stage Anaerobic Digester 1°S

Wastewater Treatment (Preliminary) Bar Racks and Screens Bar racks and screens remove large solids which could clog pumps and pipes in the wastewater treatment plant. Solids are collected and sent to a landfill.

Wastewater Treatment (Primary) Settling Tank Settling tanks remove the large solids which remain suspended in the wastewater and about 50% of the oxygen-demanding substances. The solids are sent on for further treatment (sludge digestion) and ultimate disposal.

Wastewater Treatment (Secondary) Activated Sludge In the activated sludge process, bacteria and other microorganisms are used to remove small solids and oxygen-demanding substances present in the wastewater. Outflow from this tank undergoes settling and the excess sludge is sent on for further treatment (sludge digestion) and ultimate disposal.

Wastewater Treatment (Tertiary) Tertiary treatment refers to any of a variety of biological, chemical, and/or physical methods used to reduce levels of specific pollutants in a wastewater stream. Among these are levels of solids and oxygen-demanding materials, toxic metals and organic chemicals, and algal nutrients such as nitrogen and phosphorus. All wastewater treatment plants (>2 MGD) discharging to the Great Lake are required to remove phosphorus. This is often accomplished through chemical precipitation as described below. Phosphorus removal by precipitation … Ferric chloride, Fe(Cl)3 producing Fe. PO 4 and Fe(OH)3 Alum, Al 2(SO 4)3· 18 H 2 O producing Al. PO 4 and Al(OH)3

Wastewater Treatment (Tertiary) Carbon adsorption is an incredibly effective means of removing organic chemicals from wastewater … chemicals which would otherwise pass through the plant and enter the environment. This technology is also applied in drinking water treatment, both municipally and with consumer-installed devices.

Wastewater Treatment (Disinfection) Ultraviolet Light Disinfection is the most important step in wastewater treatment because it removes pathogens and thus protects receiving waters used for contact recreation and as a drinking water supply. Chlorine is the most commonly used disinfectant. Because of adverse effects on the environment, chlorine is being replaced by other methods such as ozonation and ultraviolet light (the method used a our plant in Houghton.

Wastewater Treatment (Sludge) Incineration A variety of means are available for ultimate disposal of sewage sludge. Landfilling and incineration are the most common. Here, the sludge is introduced to the top of a multiple-hearth furnace. The sludge dries and ultimately ignites as it moves down the surface toward the fire. The product is ash (landfilled) and stack gases which are collected for further treatment.

Wastewater Treatment (Effluent)

• • Coursework CE 4507 - Wastewater Collection & Water Distribution CE 4508 – Water & Wastewater Treatment and Design CE 4509 – Environmental Process Simulation CE 5501 - Environmental Process Engineering CE 5502 - Biological Waste Treatment Processes CE 5503 – Physical-Chemical Treatment Processes CE 5507 - Sorption and Biological Processes Students have the option of building a ‘concentration’ in water and wastewater treatment as part of the B. S. in Environmental Engineering at Michigan Tech.

Employment • • Government (MDEQ, City of Detroit) Industry (GM, Kodak) Consulting (CH 2 M-Hill, Montgomery-Watson) Graduate Study & Research (U. S. EPA, MTU) Check out the web pages of these organizations for professional opportunities.

Study Question Where does the wastewater from your home go? What kind of treatment system is utilized? Reading Assignment Take a wastewater treatment plant tour (“Go With the Flow”) courtesy of the Water Environment Federation. http: //www. wef. org/publicinfo/#