Midterm Flashcards
(166 cards)
1
Q
What is Environmental Engineering?
A
Study of environmental solutions
2
Q
What is the environment?
A
The aggregate of surrounding things, conditions or influences, especially affecting the existence or development of someone or something.
(1) <strong>Circumstances and conditions</strong> that surround (and affect) an organism or a group of organisms
OR
(2) <strong>Social and Cultural conditions </strong> that affect an individual or community.
3
Q
What is the “physical” environment?
A
- Air, Water, Lands, Oceans, Rivers and Forests
- Buildings, Highways, and modern infrastructure of the urban settings (in increasing extent)
4
Q
What does the State of the Physical Environment Affect?
A
State of Physical environment affects the viability
of all living things on the planet: People, Flora and
Fauna
5
Q
What are the Criteria Air Pollutants?
A
1- Ambient Air Pollution
2- Indoor Air Pollution
3- Occupational (industrial Hygiene) Air Pollution
4- Personal Exposure
6
Q
What is Ambient Air Pollution? What is the classification?
A
Ambient Air Pollution
• In the outdoor environment
• Involves a complex array of sources and pollutants, meteorological transport of the pollutants to a receptor, and a wide range of social, economic, and health effects.
7
Q
What is Indoor Air Pollution? What is the classification?
A
Indoor Air Pollution
• Radon gas exposure and passive cigarette smoke, mole, etc.
• Many Canadian jurisdictions do not have specific legislation for indoor air quality issues.
• ONLY “general duty clause” applies:
• Employer must provide a safe and healthy workplace employer’s duty to maintain the indoor air quality.
• Government of Canada has prepared a number of publications on air quality.
• In the United States, the Occupational Safety and Health Administration (OSHA) has compiled information on Indoor Air Quality.
• Building codes in Canada and the U.S. generally refer to the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) Standard 62.1‐2010 ‐ Ventilation for Acceptable Indoor Air Quality (or previous versions), or other acceptable standards.
• ASHARAE 62.1‐2010 (http://arco‐hvac.ir/wp‐content/uploads/2016/04/ASHRAE‐62_1‐2010.pdf)
8
Q
Describe the category: Occupational (Industrial Hygiene) Air Pollution.
A
- Occupational (Industrial Hygiene) Air Pollution
• Exposure to a large range of pollutants (particles, mists, acid vapors, and organic and inorganic gases) in the workplace.
9
Q
Describe the category: Personal Exposure.
A
- Personal Exposure
• This final category refers to exposure to dust, fumes, gases, or mists to which an individual exposes oneself. Examples include cigarette/cigar smoking, sniffing of glue, and many other practices which can cause damage to the human body.
• Exposure to dust, fumes, gases, or mists to which an individual exposes oneself.
• E.g. cigarette/cigar smoking, sniffing of glue, and many other practices which can cause damage to the human body.
10
Q
What are the 2 big Air Pollution Incidents?
A
Donora Smog of 1948
Great Smog of 1952 (which killed 4,000 Londoners)
11
Q
What is Photochemical Smog?
A
The product of chemical reactions triggered by sunlight (photochemical reactions). These chemicals are comprised of NOx and hydrocarbons which make up ground-level ozone.
12
Q
What is Bad Ozone?
A
Ground-Level Ozone, known as bad ozone, is an extreme oxidant which is very reactive. It is known to cause many health problems because it attacks lung tissue, reduces lung function and sensitizes it. It is made up of NOx and VOC’s (volatile organic compounds) which are mainly hydrocarbons.
13
Q
What do HAPs stand for? What are they?
A
HAP’s (Hazardous air pollutants) aka Air toxics.
HAP’s are present in much smaller quantities than air pollutants. The list is at 189 and increasing with new research. Industries must abide by the legislation accorded for each of them. To control industries cannot produce for more than 10 tons per year or a combined limit of 25 tons per year of these toxics.
Examples;
Benzene (in gasoline)
perchloroethylene (PCE) (solvent in dry cleaning facilities)
methylene chloride (solvent and paint stripper)
dioxin, asbestos, toluene
heavy metals: Cd, Hg, Cr and Pb compounds.
14
Q
What is TRI?
A
Annual Toxic Release inventory that reports annual mass emissions of toxic substances from specific facilities
15
Q
What is Acid Rain?
A
Acid disposition refers to the fallout of particles or any time of precipitation (rain, fog, hail) that is more acidic than normal (greater than 5-5.5 pH)
16
Q
What does Surface waters include?
A
lakes, streams and rivers that subsequently flows into the oceans.
17
Q
Oceans cover how much %?
A
70%
18
Q
What does the groundwater refer to?
A
groundwater refers to underground water sources. These sources are made from water percolating through the earth’s surface.
19
Q
Name some major water contaminants.
A
1- Pathogens 2- Organic Waste 3- Nutrients 4- Toxic Organic Chemicals 5- Toxic Metals 6- Sediments and suspended solids 7- Acidity 8- Salts 9- Heat
20
Q
What are point sources vs Non-point sources?
A
Point sources: discharge points such as the outfall pipe from a factory or wastewater treatment plant.
Non-point sources: runoff from agriculture lands, erosion from mining and construction activities and fall outs r dispositions from the atmosphere.
21
Q
What are Pathogens? How do they affect water quality?
A
Are disease-causing agents such as viruses, bacteria, protozoa, and parasitic worms. As we grow up chain organisms grow and are capable of carrying more diseases. Pathogens are usually very controlled in water supplies since they can cause life-threatening diseases. In many nonindustrial counties, this is a big problem
22
Q
What is Organic Waste? How do they affect water quality?
A
The main source of oxygen-depleting substances in surface water. Dissolved oxygen is the most important requirement for aquatics life to exist. Depletion exist naturally with water fluctuations
23
Q
What are BOD’s and COD’s?
A
BOD (Biological Oxygen Demand) is the demand for oxygen by bacteria.
COD (Chemical Oxygen Demand) is a greater oxygen demand on waters since some substances trigger chemical reactions.
Example: sewer ~300BOD, Pig manure factory ~100 000 BOD.
24
Q
How do Nutrients affect water quality?
A
Nitrogen and phosphorus needed to support vegetation and other life. These chemicals are widely used in fertilizers and detergents. When they reach surface
waters they become responsible for the over-enrichment of nutrients. (Eutrophication happens)
A eutrophic body of water supports an abundant growth of algae that can crowd out other forms of aquatic life. For drinking water, this can cause blue baby syndrome which restricts oxygen transport in the bloodstream of newborns.
25
What are Toxic Organic Chemicals? How do they affect water quality?
Built of Carbon and other atoms which make up living things. These toxics chemicals are extremely mutagenic. Can damage vital organs and are carcinogenic. Oil spills in waters are of great concern. Once they reach the coast they can cause 3 generations worth of disaster. (Highest product is gasoline and lower is asphalt). DDT and VOC’s part of toxic organic chemicals as well. Substances such as vinyl chloride in solvent are extremely harmful if in water. More present in groundwater since it is hard to evaporate.
26
What are Toxic Metals? How do they affect water quality?
Mercury, arsenic, lead => most toxic of the metals. Can damage vital organs and kill. Some metals are found naturally in waterways but human activities have altered the levels and distribution of toxic metals. Metal smelting and other industrial processes are main activities.
27
What are Sediments and suspended solids? How do they affect water quality?
suspended soil particles in water. Stops light from penetrating which in turn does not allow aquatic life to grow. They can also harm aquatic organisms by destroying natural habitats. Land erosions from mining has caused higher levels of siltation.
28
How does Acidity affect water quality?
Water acidity must usually be in normal range. Most change in normal acidity is due from industrial processes. A lot of organisms cannot survive under 5.5 pH.
29
How do salts affect water quality?
75% of our planet covered with water and most of it is unfit for human use because of high salt concentration. Compounds which produce positively charged ions in
solution. Measured in TDS. (TOTAL DISSOLVED SOLIDS). Sea water TDS is 60 x more than drinking water. The effect of salinity depends on water use since different organisms have different salt tolerances. Salinity is controlled depending on its use.
30
How does heat affect water quality?
High heat can damage just about anything. Thermal pollution is another way that human activity can affect the quality of water. Comes from electric power plants. Warm water holds less oxygen and much aquatic life are sensitive to temperature change.
31
What does MCL stand for?
Maximum contaminant level
32
What does Ignitability mean?
an ability to burn easily
33
What does Corrosivity mean?
Strong acids or bases or substances able to corrode metal
34
What does Reactivity mean?
An ability to react violently or cause explosions including reactions with water.
35
What does Toxicity mean?
an ability to threaten water supplies and health, determined by laboratory test of leachability
36
TCLP?
EPA developed it to check weather a substance meets the toxicity criteria.
It stands for Toxicity Characteristic Leaching Procedure
37
RCRA?
It stands for Resource Conservation and Recovery Act. Under it is where hazardous and non hazardous waste is defined and calls for control.
38
CERCLA?
It is the Superfund. (Comprehensive Environmental Response, compensation and liability act). It is Able to pay in order to decontaminate sites. 8.5 billions $
39
Non-Hazardous Waste
It is Trash and Garbage. Regulates by the municipality.
40
Landfills compared to incinerators:
U.S. and Canada uses them. Linear has become important because it can reach the ground. In Europe, Incinerators are used.
41
MSW?
Municipal Solid Waste Management
42
Radioactive waste:
Comes from Military and Civilian Use of Energy. 1954 Atomic Energy Act but in 1970 taken over by NRC (Department of Energy and Nuclear regulatory commission). Responsible for radioactive waste. State authorities only responsible for low-level waste
43
High-Level Waste:
Spent fuel in nuclear reactors and reprocessed spent fuels to make plutonium and uranium. It requires permanent isolation for the human environment. Classes are alpha
(cm penetration), beta (meters) and gamma (km). Yucca Mountain site was supposed to be final spot, but Obama killed this off due to transportation concerns. It remains stored at power plants and government facilities.
44
Transuranic Waste (TRU):
Result of weapons production, principally the fabrication of plutonium weapons components, chemical separation of plutonium and recycling of plutonium from production scraps, residues or retired weapons. Since it has long half - life like high - level waste it can remain radioactive for hundreds of years. The U.S. department of Energy (DOE) currently manages this waste
45
Low-Level Waste:
LLW is anything not classified as the others. 80 comes from civilians and 20 from military. Examples are cloths like gloves and glasses used by nuclear power plant workers or bottles and test tubes in medical research. LLW has class A B and C (A being least dangerous because least radioactive and shortest-lived material). State governments are responsible of low level waste. Approved method to put in drums and await treatment of disposal
46
Uranium Mill Tailings
Largest volume of radioactive waste is sand-like residue that comes from processing uranium ore. 2000kg must be processed for 1kg of enriched uranium for nuclear reactors. Residues are from refining uranium ore (milling) is called mill tailings
47
Renewable and Non-renewable resources
Renewable have capacity to be replenished whereas non-renewable exist only in limited, finite, amounts.
48
Land Use and Impact
Ecosystem refers to any biological community that functions as a cohesive unit within the physical environment
49
Framework for Environmental Issues:
https://i.imgur.com/VFY5N5n_d.jpg?maxwidth=640&shape=thumb&fidelity=medium
50
Give examples of Waste emissions or residuals discarded to the environment
Waste emissions or residuals discarded to Environment
• Air pollutants (combustion of fossil fuel( e.g. automobile,
factory, power plant)
• Water contaminants (pulp manufacturing, etc.)
• Solid Wastes (municipal)
• Pesticides
51
What is Photochemical Smog?
The product of chemical reactions triggered by sunlight (photochemical reactions). These chemicals are comprised of NOx and hydrocarbons which make up ground-level ozone.
52
What is Ozone?
Ground-Level Ozone, know as bad ozone, is an extreme oxidant which is very reactive. It is known to cause many health problems because it attacks lung tissue, reduces lung function and sensitizes it. It is made up of NOx and VOC’s (volatile organic compounds) which are mainly hydrocarbons.
53
Describe the History of Metallurgy
Started with Stone Age going back 8000 years ago. Only forming of metals with their natural form. Then came smelting (around 4000 B.C where adding tin to copper (1:2) to produce bronze. In early Babylonia, Iron was valued 8 times more than silver and in Egypt copper more valuable than gold for a certain time.
- Carburizing( giving Iron more strength by heating in the presence of carbon, such as coal.
- Quenching( making the heat reduce quickly.
- In Asia was really beginning of Iron Age, yet china still used bronze for a time. With the rise of the Greek empire, metal production greatly increased. Isolation of mercury was done by them.
- Roman empire followed by manufacturing iron and steel for tools, weapons and farming. Gold and silver started to be used in monetary form. Also use of lead was everywhere in for water pipes and tanks as well as food storage containers.
- The 1970s was a big step: A different way of smelting. Instead of using charcoal to use coke. This lead to an industrial revolution. Everything now made was with Iron.
- 1840( about 40 metals knows.
- 1990’s( 70 metals.
-Trace metals: Metals found in low concentrations.
54
What is Carburizing?
giving Iron more strength by heating in the presence of carbon, such as coal.
55
What is Quenching?
making the heat reduce quickly
56
What are trace metals?
Metals found in low concentration
57
Describe the distribution of trace metals in the environment.
Distribution of trace metals in the environment: Human activities have increased the amount of trace metals in our environment. Mining and metal smelters are the main cause of this. Methods have been developed to calculate human exposure to lead and other toxic metals.
58
Describe some exposure pathways
Inhalation of air, ingestion of water, ingestion of food and ingestion of dust
59
How do you calculate the absorption in a medium?
Ai=Ci Ui Fi; i= air, water, food, dust; C= Concentration of the trace metal in i;
U=uptake rate of i, F=fraction of trace metal absorbed by the bloodstream
60
What are the Traces of Metals in the Air?
(Size distribution depends on how they were formed
(From fuel combustion for example)
- Nuclei mode=0.02-0.05 um
- Accumulation mode=0.2-0.5 um
- coarse particle mode=10um
(Nasopharyngeal and tracheobronchial region is usually not related with absorption in bloodstream since it is upper respiratory system. Anything bellow which reaches pulmonary is usually absorbed in bloodstream. (EPA for lead in air=0.3).
61
What are the Categories that can contribute to metals in drinking water?
- runoff from agriculture lands containing fertilizers
- metals from industries that reach water through effluent streams
- contaminated rain and construction activities
- In some of the distribution systems in urban areas lead is used which adds significant amount of lead in drinking water
62
What is the EPA for lead in water (Environmental Protection Agency)
(EPA for lead in water=0.5).
63
What types of Trace metals get into food?
Trace Metals in food: Metal containing dust can leach metal into their contents, soldered cans, improperly applied glazes used on ceramic storage containers or plates may contain metals, especially lead.
64
What do we classify as dust and soil?
Dust and Soil: settled airborne particles. Microscopic pieces of human skin and hair, tiny insects, bits of fabric. Soil considered outdoors and is natural + contamination from human activity. High levels of metals can be found in these mediums. Leaded paint of big concern.
65
What is the Total Dose of Absorbed Metal mean?
Amount of metal absorbed instead of rate of absorption of certain metal.
66
What does the Total Doses in a population mean?
Total Doses in a population: Each person is exposed to different amounts of trace metals. Therefore for a population, we measure the concentration of a metal in human tissue, such as bloodstream in PbB (blood lead concentration). PDF in figure 10.9 comes from table 10.1 calculation.
67
What are Dose responses?
Response to a Dose: Dose-response relationships are important in setting regulations for toxic pollutants such as trace metals. They are also important for estimating various types of health risks. The maximum level exists called the threshold level, where there are no effects.
68
What does NAAQS stand for?
National Air Quality Standard
69
What does MACT stand for?
Maximum Achievable Control Technology
70
What is the NAAQS requirement?
(NAAQS) National Air Quality Standard. Regulates this and requires all regions of the United States to demonstrate that airborne lead concentrations will not exceed the standards.
71
What is the MACT requirement?
(MACT) Maximum Achievable Control Technology adopted in 1990. Industries that emit hazardous air pollutants are required to show that they are using MACT to reduce emissions. Also, industries are thinking about changing processes by using green design and industrial ecology for their products.
72
What are greenhouse gases? name some examples:
Carbon Dioxide (CO2) ( Biggest Cause of GHG effect, Comes from Fossil F Combustion
Methane (CH4) ( Decomposing landfill, animal digestive tracts, gas production and coal
Nitrous Oxide (N2O) ( Nitrogen-containing Chemical fertilizers
CFC-11, 12, 113 ( Halocarbons, Refrigeration systems and aerosol cans, Banned
HCFC-22( Perhalogens, industrial applications, increased after the ban of CFC’s
73
What is the GHG effect?
Atmospheric absorption of outgoing IR radiation from the earth. The energy absorbed will reradiate back to earth by greenhouse gas molecules. Warms earth beyond equilibrium of -19 degrees Celsius.
Presently, GHG’s responsible for a warming of 34 degrees Celsius. This is, therefore, a natural occurrence to have in order for life to exist as it is now on earth.
The problem is that GHG’s are increasing which subsequently is increasing the temperature of the earth. This is the environmental concern we face and what needs to be done is a stabilization of greenhouse gasses.
74
What is the difference between climate and weather?
Climate is more stable than weather. It varies over longer period. (Average of 30 years needed usually to calculate average climate of a region.) Radiative heat exchanges govern climate temperature.
75
How do you calculate Heat Flux?
Q(dot)max = sigma(A)(T)^4
q(dot) = Heat Flux=Qmax/A (W/m2)
sigma = (5.67 x 10^-8) W m^-2 K^-4
https://i.imgur.com/oZw2t1p_d.jpg?maxwidth=640&shape=thumb&fidelity=large
76
Black Body Radiation:
Sun= 5800K ( So=solar input, 342 W/m2 average
Earth( Te4 = Temperature of earth W/m2
These bodies will emit EMW with lambda = C/V
and lambda(max) = 2898/T
77
Simple Earth Energy Balance is equal to:
```
Outgoing radiation (W/m2)
q(dot)earth = sigma(Te)^4
```
https://imgur.com/QlUkRZV
78
Photon Energy (E) is equal to:
E = hv , Energy (J) ,Planck's constant (6.6260x10^-34) (h) * photon frequency (v)
79
Wavelength is equal to:
Wavelength = c/v , speed of light 3x10^8 m/s (c), v is the photon frequency
80
Energy (with wavelength substituted) is equal to:
E = hc/v , h is plank's constant 6.6260x10^-34, c is the speed of light in a vacuum 3 x 10^8 m/s , v is the photon frequency.
81
What is the Emissive power of a black body?
E(dot)subscript(lambda) = C1/(wavelength^5(e^(C2/(wavelength*Temperature)) -1))
E(dot)lambda = rate of energy emitted by a black body per unit area and wavelength (W/m^2-micrometres)
https://imgur.com/h9QECAl
82
Describe the Troposphere:
Average Height = 10km
contains 80% of the mass of all atmospheric gasses
N2, O2 and trace gasses (water vapour, argon and CO2)
83
Describe the Stratosphere:
The atmospheric region above the troposphere
Oxygen O2 and Ozone O3 which absorb incoming UV radiation.
Protects the earth's surface from damaging high-energy radiation UV-C (0.20 - 0.28 micrometres) and UV-B (0.28 - 0.32 micrometres).
84
Describe Outgoing waves Outgoing Waves:
Infrared (0.4 and 0.7 micrometres)
| Captured by CO2 and H2O water vapour
85
What are Solar Energy waves?
- So which comes as UV waves. (7um and 3um)
| - Absorbed by O2 and O3.
86
What is radioactive forcing?
- Any change in the average net radiation (delta qdot) at the tropopause is delta F.
- It is used because any change in Radiative balance will force climate system to readjust in order to restore equilibrium.
87
How is radioactive forcing produced?
1. By changing solar input radiation ( Increase would mean positive forcing (warm)
2. Changing Albedo ( melting of ice sheets would mean positive Radiative forcing because less radiation would be reflected back to space.
3. Addition of aerosols (suspension of fine particles less than 10um in dia, most important are ones from the combustion of biomass and fossil fuels) in the atmosphere.
( tend to reflect incoming solar radiation, negative feedback (cold)
-Figure 12.9 & 12.10
88
What does the Equivalent CO2 mean? (in terms of Total Radiative Forcing)
- Quantifying the combined effects of multiple atmospheric constituents.
- Total Radiative Forcing from multiple greenhouse gasses can be expressed as an equivalent CO2 that would produce an overall forcing.
89
What is the Sensitivity Factor?
- The change in surface temperature of the earth over change in Radiative forcing at top of troposphere. (page 499)
- Gamma is important since and results from data show that it goes from 0.55 to 0.65 C/ W-m-2. Therefore a positive feedback currently exists (warming effect).
90
What is the climate model?
- GCM (General Circulation Model) which accounts for the complex physical and chemical processes that govern the atmosphere. These models have the principles of conservation of mass, momentum exchange and energy conservation as a basis.
- A doubling of CO2 would mean an increase of 2.5 degrees. This is another measure of climate sensitivity that is used with GCM’s.
91
What are the Climate Change Predictions and Temperature change since preindustrial times:
- Figure 12.
- Equivalent CO2 has risen drastically since last century.
- Prediction is that temperature is increasing at higher rate.
92
Historical Observations about Green House Gasses:
- Measures have been made to deduce past climate trends going back millions of years.
- Vostok, Antarctica test station Analysis of core samples provides dramatic climate evidence over past 420 000 years.
- For most of the million years, Earth has always been much colder. Since last ice age
(10 000 years ago) earth Temp relatively stable, until now. CO2 and other gases is increasing inside Ice Cores samples.
93
What are the Greenhouse Gasses Lifetimes?
The longer the atmospheric lifetime of a substance, the more difficult the stabilization objective becomes. Water Vapour, for example, has a short lifetime; subsequently, aerosol particles have a short atmospheric lifetime as well. Yet CO2 can stay and accumulate for thousands of years.
94
Describe the Carbon Cycle
- CO2 is very stable and non-reacting chemical.
- Was balanced over thousands of years until human activity disrupted the system by extracting carbon from the earth’s crust (fossil Fuels) and injecting it in the atmosphere.
- From Bern model, of the Anthropogenic CO2 added to the, half will remain even if emissions were to completely cease. This is why the policy goal worldwide is to stabilize CO2 emissions. Diminishing is widely seen an unrealistic strategy which is not likely to occur in our lifetime.
https://imgur.com/a/QfICNfp
95
What does GWP stand for? What is it?
- Global warming potential is very powerful tool, since this is universally accepted.
- It shows how bad the situation is.
96
What is the framework of environmental issues?
https://imgur.com/a/9ilf0JK
97
What are the waste emissions or residuals discarded to the environment?
- Air pollutants (combustion of fossil fuel eg. Automobile, factory, power plants)
- Solid Wastes (municipal)
- pesticides
98
What are some physical, chemical and biological changes in time and distance? Give some examples
Example 1: Gaseous sulfuric acid becomes partially oxidized to Sulfate particles in the atmosphere -> Acid Rain damaging lakes and forest
Example 2: Oxygen depletion in rivers and streams due to organic waste discharged from factory and house
99
Describe some complex interactions between the environment change and human activities:
1- Clear-cutting for agriculture - > soil erosion, loss of soil nutrients, unsustainable agricultural production
2- Modern Technology -> air and water contaminants -> human illness & ecological damage.
3- Global warming and other emerging pollutants (e.g. nanoparticles, microplastics in drinking water, endocrine disruptors
100
How to weigh the tradeoff and make a decision?
- Political Process
* Adopting policy measures (law and regulations) to prevent, alter, or reverse the changes that are expected.
- Environmental Policy:
Significant economic implications -> influenced by private and public interests
101
Why is it important for engineers to understand the environmental issues?
Engineers are concerned with (and responsible for) a wide range of activities that directly or indirectly contribute to environmental change.
102
Give some examples of engineer's direct responsibility to environmental impacts:
Petrochemical refineries, paper mills, power plant,....... (Chemical
and mechanical engineers)
Water treatment plant,… (Civil engineers),…
Microchips,… (Electrical and computer engineers) ,..
Steel mills, aluminum smelters,… (Metallurgical engineers), …
Consumer products (batteries, toasters, light bulbs, automobiles,
103
What is green enginering? (EPA)
Design, commercialization, and use of processes and
products, which are feasible and economical while
minimizing:
1) generation of pollution at the source and
2) risk to human health and the environment.
Green engineering embraces the concept that decisions
to protect human health and the environment can have
the greatest impact and cost-effectiveness when applied
early to the design and development phase of a process
or product.
104
What are the principales of green engineering?
* Engineer processes and products holistically, use systems analysis, and integrate environmental impact assessment tools.
* Conserve and improve natural ecosystems while protecting human health and well‐being.
* Use “life‐cycle thinking” in all engineering activities.
* Ensure that all material and energy inputs and outputs are as inherently safe and good as possible.
* Minimize depletion of natural resources.
* Strive to prevent waste.
* Develop and apply engineering solutions, while knowing local
geography, aspirations, and cultures.
• Create engineering solutions beyond current or dominant technologies; improve, innovate, and invent (technologies) to achieve sustainability.
• Actively engage communities and stakeholders in development of engineering solutions.
105
What is the environmental LCA?
LCA = Life Cycle Assessment
LCA is a technique to assess the environmental aspects
and potential impacts associated with a product, process, or service, by:
* Compiling an inventory of relevant energy and material inputs and environmental releases;
* Evaluating the potential environmental impacts associated with identified inputs and releases;
* Interpreting the results to help you make a more informed decision.
106
What are some of the Basic Engineering Principles?
Conservation of Mass:
Mass (m) = Density (p) x Volume (V)
https://imgur.com/POGlZAl
107
What are some environmental health effects?
Health Effect:
• Acute-immediate response in the human body
• (e.g., CO inhalation)
• Chronic - long term exposure to pollutants
• Exposure to high-level particulates –chronic repertory illness, asthma
• Carcinogenic
• The main concern these days
108
What is air pollution?
Air Pollution = “Presence in the outdoor/ or
indoor atmosphere of one of more contaminants
or combinations thereof in such quantities and of such duration as may be or may tend to be injurious to human, plant, or animal life, or property or which unreasonably interferes with the comfortable enjoyments of life or property or the conduct of business."
109
What are some known by-products of air-pollutants?
```
Carbon Monoxide (CO)
Sulfur oxides (SO2)
nitrogen oxides (N2O, NO, NO2)
fly ash and unburn hydrocarbons
```
110
What are the issues of air pollution and the high population areas?
Population growth, accelerating urbanization, high standard of living -> High concentration of air pollutants in localized areas.
111
What does PM stand for? What does it mean?
PM = Particulate Matter
The mixture of small solid or liquid particles suspended in air (Total suspended particulates (TSP))
eg: acids, (such as nitrates and sulfates), organic chemicals, metals, and soil or dust particles.
eg: Technology-related emissions: fuel consumption (ash, soot) and industrial and manufacturing process.
112
What does PM10 mean?
particles diameter < 10 micrometres
generally pass through the throat and nose and enter the lungs.
once inhaled, it may affect the heart and lungs and cause serious health effects.
113
What are the 2 EPA categories for particle pollution?
- Inhalable coarse particles (2.5 micro-meters < diameter < 10 micro-meters) eg: roadway dust and dusty industries
- fine particles (dia < 2.5 micrometres) eg: smoke, haze, forest fires, gases emitted from power plants, industries and automobiles react in the air.
114
What are the sources, effects of Sulfur Dioxide (SO2)?
Sources:
Primary emission sources: fossil fuel combustion at power plants (73%) and other industrial facilities (20%)
Smaller sources: industrial processes such as extracting metal from ore and burning of high sulfur containing fuels by locomotives, large ships and non-road equipment.
SO2 from a power plant and other sources can undergo chemical reactions in the atmosphere:
- forms gaseous sulfate and sulfate particles.
- falls as acid precipitation (ACID RAIN)
115
Describe Carbon Monoxide
- Orderless, colourless and toxic gas due to incomplete combustion
- Lower levels of exposure -> causes mild effects that are often mistaken for the flu (headaches, dizziness, disorientation, nausea and fatigue)
116
Describe Nitrogen dioxide (NO2)
• Reddish-brown gas
• Toxic in high conc.
• At low conc. irritate respiratory system and
produce respiratory illness (bronchitis).
• Children are susceptible to elevated NO2 level.
• N2 + O2 -> 2 NO (Heating in engine (2000◦
C)
• 2 NO + O2 -> 2 NO2 (Cooling in exhaust)
• 2NOx -> xO2 + N2 (Catalytic converter)
• Also causes other pollutants. NOx causes acid
deposition and formation of ground level O3
• SO2 and NOx chemically react in atm. and form
fine nitrate particles (PM 2.5)
117
Describe Lead (Pb)
Heavy metal found naturally in the environment as well as in manufactured products.
• Sources:
• Past:
• historically from fuels in automobiles (unleaded gasoline) and industrial sources.
• 98 % emissions reduction and 94% level in air reduction between 1980 and 1999
* Today:
* Highest level is usually found near lead smelters.
* Major emission sources to the air: ore and metals processing and piston-engine aircraft operating on leaded aviation gasoline.
• Exposure pathway:
• air, drinking water (lead pipe), lead-contaminated food, incidental ingestion of lead-contaminated soil
and dust, lead-based paint (older homes, built before 1978), toys.
• Distributes throughout the body in the blood and is accumulated in the bones.
Effects:
• Depending on the level of exposure, can adversely affect the nervous system, kidney function,
immune system, reproductive and developmental systems and the cardiovascular system.
• Infants and young children are especially sensitive to even low levels of lead, which may contribute to
behavioural problems, learning deficits and lowered IQ. (Children absolve 70%, adult 20%)
118
What are the causes and effects of ACID RAIN / ACID DEPOSITION?
ACID DEPOSITION (Acid rain)
• pH < 5.6 (natural rain)
Causes:
• Transformation of SO2 and NOx into dry or moist secondary pollutants such as sulphuric acid (H2SO4), ammonium nitrate (NH4NO3) and nitric acid (HNO3)
* Wet deposition is acid rain, the process by which acids with a pH normally below 5.6 are removed from the atmosphere in rain, snow, sleet or hail.
* Dry deposition takes place when particles such as fly ash, sulphates, nitrates, and gases (such as SO2 and NOx), are deposited on, or absorbed onto, surfaces. The gases can then be converted into acids when they contact water.
Effects
• Acidification of lakes and streams directly affect fish and other aquatic organisms
• pH affects the functioning of enzymes, hormones, and other proteins in all living organisms. -> killing sensitive species and preventing from reproducing
119
What are the Cause and effects of Stratospheric Ozone depletion?
Effects of ozone layer depletion:
• Skin cancer, cataracts, blindness
• Reduced immune function
• Harm algae and phytoplankton
Ozone‐Depleting Substances (ODS):
• CFCs (chlorofluorocarbons) (or known as Freon (DuPont))
• Manmade chemicals
• Nonreactive, nonflammable, nontoxic -> suitable for refrigeration, air conditioning, manufacturing foam, cleaning electronics, propelling the contents of aerosol cans.
• Began production in 1940 -> rapid grow in use
• Ozone depletion process:
• ODS remain in the atmosphere from 20 to 120 years or more -> Find way to stratosphere (may take decades)
120
What does ODS stand for?
Ozone‐Depleting Substances
121
What are Greenhouse gases (GHGs)?
Mainly H20 and CO2
• Trap heat in atmosphere (Ch. 12)
• Shortwave length radiation from Sun (UV)
• Partially absorbed by earth’s surface
• Warmed earth’s surface radiates back to space at longer wavelength (infrared).
• Balance determines temp. of earth.
122
What are the 6 signs of global warming discussed in the slides?
1. Global temperature rise
2. Warming Oceans
3. Shrinking ice sheets, Glacial retreat
4. Sea level rise
5. Extreme events (heat wave, droughts, heavier
storms, floods, increased hurricane strength and
frequency, increased winter storms, etc.)
6. Ocean acidification
123
What are the effects of Pb on the body?
learning and behavior disorder, motor coordination problem
| Attack kidney, reproductive system, hematopoietic system
124
What are the effects of Ni, Cr on the body?
Respiratory cancer, skin disease
125
What are the effects of Cd on the body?
Kidney function problem
126
What are the effects of Hg on the body?
Nervous system and brain damage
127
Name the 4 pathways routes to human exposure.
Air, Water, Food, Soil and Dust
128
How do you calculate the Mass of trace metal absorbed by the body/time
```
Ai = CiUiFi
i = media
Ci = concentration of trace metal in medium i[M/L^3]
Ui = Uptake rate of media [M^3/T]
Fi = fraction of trace metal absorbed by bloodstream
```
129
What are trace metals in air? Their form and diameters
Forms of gases or particles:
mercury in vapour phase, airborne metals as solid particles
Aerodynamic diameter (um): dA
• diameter of a sphere of 1 μm and density 1g/cm3 with the same
settling velocity as the particle of interest.
• The aerodynamic diameter standardizes for:
Shape: Sphere
• Density:
The density of a water droplet
1000 kg/m3 = 1 g/cm3 = 1 g/ml
* d < 0.1 μm: behaves like molecules (random motion)
* 1 μm < d < 20 μm : follow motion of the gas stream (low inertial motion)
* D > 20 μm: considerable settling velocity and tend to settle to the ground in a short duration
130
What is the trimodal distribution?
The distribution of particle mass in the atmosphere.
131
What are the 3 categories for particle diameter in the trimodal distribution
```
Nuclei mode (0.02-0.05 um)
Accumulation mode (0.2-0.5 um)
Coarse particle mode (10 um or even larger)
```
132
Solve this problem: child Cair= 1 μg Pb/m3 , Uair= 10 m^3air/day -> Mass absorbed by body/day Aair= ?
= 1 μg Pb/m3 x 10 m3air/day x 0.3 = 3μg Pb/day
133
How do you calculate the deposition of a particle? (dp)
range: r1 to r2 in um
logdP = (log(r1)+log(r2))/2
dp = 10^log(dp)
134
What are the sources of trace metals in the water?
- Runoff from agriculture lands containing fertilizers and pesticides -> metal to drinking water supply
- Effluent streams containing metals from industry
- Disrupted earth crust by construction activities may release trace metals.
135
what is fraction of trace metal entering the body via inhalation that is eventually absorbed into the bloodstream for lead? (fair)
fair of lead is 0.3
136
What is the trace of lead that enters the bloodstream through water?
fwater = 0.5 for Pb
137
what are the trace of lead that enters the bloodstream through food?
its equal to fwater (0.5)
138
What is the lead absorbed by the child (https://imgur.com/a/z7GDo0j)
Calculations: https://imgur.com/a/dAhwoa1
139
What is the total dose equal to? (formula)
Total Dose (Dtotal) = Atotal x t = intergral from 0 ->t of(Atotal(t) dt)
https://imgur.com/a/p1Wl4ZC
140
calculate the total dose of the child in air.
| use C = 1ug/m^3 , t = 10m^3/day f = 0.3
Dair= A x t = C U f = 1 μg /m^3
* 10m^3/day * [2 * 365]day/year * 0.3
= 2190 μg lead
141
Airborne conc. of lead Co =1 μg/m^3 at t = 0.
| Then, linear decrease to 0.8 μg/m^3 over 2 yr period
[Cair(t)= Co(1 ‐ 0.1 t), t = yrs].
(TAKE INTEGRAL OF Aair dt = integral((Cair)(Uair)(Fair)) dt
= (Cao)(Uair)(Fair) * integral of(1-0.1t)dt evaluated from 0 to t which is 2 in our case)
= (Co) (Uair) (fair) (t-0.1t^2)/2 |(evaluated from 0 to 2)
= 1 μg/m3 * 10m3/day *(365 days/yr) * 0.3(2‐0.2)
=1970 μg lead
https://imgur.com/a/OSirad1
142
How do you calculate the dose in a population?
PDF = Samples/ (total samples * interval)
ex: 5 people, PbB from 0 to 5 ug/dl, total sample = 500
PDF = 5/ ( 500 * 5 ) = 0.002 ug/ dl
143
What is the equation of the probability density function PDF
f(x) = 1/(std sqrt(2pi)) exp((-(x-u)^2)/2 std^2)
https://imgur.com/a/NJpcwcc
144
Determine the fraction of people with blood
lead concentration less than 22.5 μg/dl. P(X<22.5)
where the mean is 22.5 ug/dl
z = x- mean / std = 22.5 -22.5 /5.8 = 0
phi(z=0) *look up on table*
0.5 or 50%
145
Determine the fraction of people with blood lead
| conc. between 20 μg/dl and 30 μg/dl. (mean of x is 22.5)
x = 20 -> z = 20 -22.5 / 5.8 = -0.43
x = 30 -> z = 1.29
Therefore, P(20 < x < 30) = P(-0.43 < Z < 1.29)
= phi(z=1.29) - phi(z=0.43) = phi(Z=1.29) - (1 - phi(z=0.43))
= 0.9015 - (1 - 0.0664) = 0.57
https://imgur.com/a/8KZY1Af
146
Name the steps inbetween from greenhouse gas emissions to changes in global climate.
```
Greenhouse has emissions ->
increase in atm concentration ->
increase in radiative forcing ->
increase in average temperature ->
changes in global climate
```
147
What does IPCC stand for?
Intergovernmental Panel on Climate Change
148
What is the expected temperature rise relative to pre-industrial temperature?
4.1-4.8 degrees celcius
149
What are the concerns that the AR5 talks about?
- Sea level rise and flooding of low-lying regions
- Increased precipitation and severity of storm events
- Increase drought
- Increased spread of tropical diseases
- A range of tropical ecological effects as plants and animals attempt to cope with rapid changes.
150
How much has the earth surface temperature increased by since the late 19th century?
up to 0.9 degrees celcius
151
What are the 6 direct causes of climate change?
```
1- global temperature rise
2- warming oceans
3- shrinking ice sheets, glacial retreat
4- sea level rise
5- extreme events
6- ocean acidification
```
152
Name some extreme events that occur more frequently because of climate change.
- Heat waves
- Droughts
- Heavy Downpours
- FLoods
- Hurricanes
- Increased winter storm in eastern north amaerica
153
How does the Ocean acidification occur?
Increase in CO2 level -> decrease in Ocean's ph
| CO2 (aq) + H20 -> H2CO3 (carbonic acid) -> H+ and HCO3- (Bicarbonate ion)
154
Name 4 greenhouse gases other than CO2.
1- Methane (CH4)
2- Nitrous Oxide (N2O)
3- Halocarbons (CFCs),
HCFCs (Hydrochlorofluorocarbons), HFCs (hydrofluorocarbons)
4- perfluorocarbons (PFCs), sulfur hexafluoride (SF6)
155
What are the KEY green house gases?
```
• CO2: Fossil fuel use and land use
change (deforestation, land clearing,
etc.)
• CH4: Agricultural activities, waste
management, energy use, and
biomass burning all contribute to
CH4 emissions.
```
• N2O: Agricultural activities, such as fertilizer
use, are the primary source of N2O emissions.
Biomass burning also generates N2O.
```
Fluorinated gases (F-gases): Industrial processes, refrigeration,
and the use of a variety of consumer products contribute to emissions of F-gases, which include hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6).
```
156
What is the definition of heat?
• Heat: energy transferred by temperature difference
157
What is conduction?
Conduction: thermal energy transport an object by a series of collisions between adjacent atoms, molecules, or electrons.
• Heat -> Increase kinetic energy in molecule (increased rate and size of vibration) - > transfer to adjacent molecule
• Thermal conductivity
158
What is convection?
Convection: transfer of thermal energy due to the motion of the
substance that contains the thermal energy (in liquids and gases where
the molecules are free to migrate)
159
What is the formula for radiative energy?
𝑸̇𝒎= 𝝈𝑻^4
Where: 𝝈: Stefan-Boltzmann
constant (= 5.67 x 10-8 W ∙ m-2∙K-4);
160
What is heat flux? How is it calculated?
q = Qmax/A = 𝝈𝑻^4
161
Body surface temperature is 20 °C, Assume black body,
| heat flux and total heat flow rate if the surface area is 0.2 m2
T(K) = 20+273= 293K
𝒒̇ = 𝝈𝑻^𝟒 =5.67x 10-8 X 2934=418W/m^2
,
𝑸̇ = 𝒒̇A = 418W/m^2x 0.2m2= 83.6 W
162
What's the temperature of the sun?
5800K
163
What is the rate of energy absorbed by the sun?
So(1-a)
a is the albedo of the earth
So is the solar input
164
How do you calculate the Energy of a Photon?
```
E = hv
h = planck's constant
v = photon frequency
```
165
how do you calculate the wavelength?
```
wavelength = speed of light / photon frequency
w = c/v
```
166
What is the emissive power of a black body?
https://imgur.com/a/gXpyjIf
