ENGR 202 Finals Review - Summary Sustainable Development and Environment PDF

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Chapter 1: Introduction to sustainable development and the role of engineers1 WHAT IS “THE ENVIRONMENT”?Environment​ refers to the physical environment that surrounds us.The environment includes: ● Air ● Water ● Land ● Oceans ● Rivers ● Forests ● Buildings ● Highways ● Modern infrastructure of the u...

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Chapter 1: Introduction to sustainable development and the role of engineers 1.2 WHAT IS “THE ENVIRONMENT”? Environment refers to the physical environment that surrounds us. The environment includes: ● Air ● Water ● Land ● Oceans ● Rivers ● Forests ● Buildings ● Highways ● Modern infrastructure of the urban setting The state of this physical environment directly and indirectly affects the viability of all living things on the planet. The welfare of these living things motivates the most environmental concerns. 1.3 FRAMING ENVIRONMENTAL ISSUES What motivates modern concerns about the environment is the expanding role that human activities play in accelerating environmental change. At the most basic level, human demands for food and shelter mean that some living things such as plants and animals will be killed or harvested for food, and some natural resources, such as trees, will be used to build structures and provide energy for shelter, cooking, and warmth. As human populations increase, more and more land is altered to provide settlements and to support activities such as agriculture, industrial processes, and transportation systems. As people become more affluent, their demand on the earth’s resources grows far beyond the basic needs for survival. In addition to altering the landscape, diverse human activities give rise to various types of waste emissions or residuals discarded to the environment. Modern examples include air pollutants from factories and automobiles, water contaminants from manufacturing processes, solid wastes from household and municipal activities, and pesticides used in agriculture.

Many of the wastes or pollutants discharged to the environment are subsequently transported and chemically or biologically transformed over time and distance. 1.3.1 Good Change or Bad? In general, our greatest concern is over environmental changes that may harm us or affect our welfare. Some environmental changes that are beneficial in the the short run may have adverse consequences later on. In preindustrial societies, the clear-cutting of forests to support agriculture was essential for providing food for a growing population. Over time, however, the continues depletion of forests often led to soil erosion, loss of soil nutrients, and a subsequent inability to sustain agricultural production. In today’s society, many air pollutants and water contaminants entering the environment as byproducts of modern technology are widely recognized sources of human illness and ecological damage. More subtle or indirect impacts, such as the effects of long-term global warming from anthropogenic emissions of carbon dioxide and other gases, are less clearly defined at the moment but raise new concerns about the longer-term effects of energy use and industrial activities. 1.3.2 Enter Public Policy In democratic societies, the political process is how decisions are made as to whether actual or potential changes in the environment are of sufficient concern to adopt policy measures  (e.g., laws and regulations) to prevent, alter, or reverse these changes. Some notion of the damages  or risks that will be avoided by taking action is one essential element of the decision-making process. Over time societies tend to address environmental problems in an order roughly equivalent to the relative risks they pose. Often this starts with basic health issues like water quality and sanitation, then broadens to include other issues of health and environmental quality. Environmental policies also are often based on concepts of fairness, or equity, such as the idea that all citizens have a right to breathe clean air. Because environmental policy often has significant economic implications, it is almost always influenced by private interests as well as the public interest.

At all stages in the policy development process, one important approach is to look for policies whose benefits clearly outweigh the cost of measures taken. Putting a dollar value on expected environmental and health benefits is especially difficult and controversial. A less controversial approach is to identify measures that are lowest in cost. The adoption of such measures often serve as an initial basis for policy actions. Environmental policies shape the development of technology in directions that reflect the goals and preferences of society. 1.4 THE ROLE OF ENGINEERING Engineers are primarily involved in problems related to technology development and deployment. Engineers also design and build all the manufacturing processes, industrial technology, and transportation infrastructure needed to extract, transport, and refine raw materials; fabricate products; and distribute the goods and services of modern societies worldwide. In order to predict the consequences of technology deployment, engineers along with scientists, also are in the study of how pollutants are transported and transformed in the environment. In the broadest sense, engineers are concerned with a wide range of activities that directly or indirectly contribute to environmental change. The way engineers design products and processes plays a big role in creating as well as solving environmental problems. Although engineers play a central role in formulating recommendations with respect to land use, the process of arriving at a final decision transcents engineering. Throughout this process, however, engineers are intimately involved in defining, collecting, and interpreting the data needed to assess the environmental implications of major land use decisions. 1.5 APPROACHES TO “GREEN” ENGINEERING 1.5.1 Sources of Environmental Impacts Materials Selection: Two key questions to keep in mind when selecting materials are “Can I use alternative materials that are environmentally preferable?” and “Can I use less material without compromising function or reliability?”

Manufacturing Processes: Refers to the methods that engineers devise to turn raw materials into finished materials and products. In most cases, every step along this chain releases waste materials to the environment in the form of air pollutants, water pollutants, and solid wastes. Energy Use: This source of environmental impacts is perhaps the most pervasive and most important of any that engineers deal with. Energy use emcompasses everything from the heating and cooling of homes and buildings, to the electricity that runs modern computers and appliances, to the gasoline and other fuels that power our transportation system.The manufacturing processes discussed earlier all require energy to perform their tasks. Any engineering improvement that reduces the energy required for a particular service will be beneficial for the environment. 1.5.2 A Life Cycle Perspective An environmental life cycle assessment (LCA) p  rovides the “big picture” of how engineering decisions in any particular area affect the environment. Stages of a product life cycle: material extraction, material processing, manufacturing, use, waste management. Environmental awareness has made it clear that all stages of a product’s life cycle must be considered in finding ways to reduce environmental impacts. Life cycle assessments are thus an important tool in implementing the concepts of green design, pollution prevention, and waste minimization that are becoming fundamental paradigms of good engineering practice. 1.5.3 Industrial Ecology and Sustainable Development Industrial ecology is the means by which humanity can deliberately and rationally approach and maintain a desirable carrying capacity, given continued economic, cultural, and technological evolution. The concept requires that an industrial system be viewed not in isolation from its surrounding systems, but in concert with them. It is a systems view in which one seeks to optimize the total materials cycle from virgin material, to finished material, to component, to product, to obsolete product, and to ultimate disposal. Factors to be optimized include resources, energy, and capital. Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs. The application of industrial ecology principles offers a means by which sustainable development can be approached and maintained. In more practical terms, industrial ecology is based on the concept that natural systems tend to recirculate and reuse materials, thus eliminating or minimizing the production of wastes and the use of energy. Industrial ecology should include: 1. Circulating and reusing material flows within the system 2. Reducing the amount of materials used in products to achieve a particular function

3. Protecting living organisms by minimizing or eliminating the flow of harmful substances 4. Minimizing the use of energy and the flow of waste heat back to the environment. 1.6 BASIC ENGINEERING PRINCIPLES 1.6.1 Conservation of Mass The law of mass conservation states that mass can be neither created nor destroyed. Rate of creation of mass = 0 (Total mass flow in) = (Total mass flow out) + (Change in mass stored) (Total mass flow rate in) = (Total mass flow rate out) + (Rate of mass storage) Mass = density x volume (m = pV) 1.6.2 Conservation of Energy (Total energy flow in) = (Total energy flow out) + (Change in energy stored) 1.6.3 The Use of Mathematical Models Engineering analysis relies heavily on the use of mathematical models to make predictions about environmental impacts and to find solutions to environmental problems.

Chapter 2: Overview of environmental issues 2.2 Environmental Concerns Human health effects of greatest concern are those that can produce severe illness or death, as from drinking contaminated water. At the other end of the spectrum are less severe effects, like the reduced lung capacity of shortness of breath that can occur from exposure to high levels of ozone or carbon monoxide from auto exhaust. In general, human health effects can be classified as acute, chronic, or carcinogenic. Acute effects occur when exposure to an environmental pollutant causes an immediate response in the human body. Long-term exposure to certain pollutants can result in chronic health effects; for example, exposure to high levels of particulate air pollution can lead to chronic respiratory ailments and exacerbate the symptoms of asthma. Finally, some pollutants, called carcinogens, initiate changes in cells that can lead to uncontrolled cell growth and division, known as cancer. Other types of environmental concerns can be classified as those related to human welfare. This category spans a broad range of impacts, including the effects of pollutants on plants, animals, and materials; aesthetic qualities like good visibility free from air pollution; recreational opportunities such as lakes and rivers clean enough to allow safe swimming; and effects on human activity on ecosystems, biodiversity, and natural resources. In recent years, the term sustainable development  has emerged as a popular way of expressing concern about the long-term viability of activities that degrade the environment in order to satisfy the immediate needs of economic development but may impair the future well-being of generations to come. 2.3 Atmospheric Emissions 2.3.1 Criteria Air Pollutants Clean Air Act of 1970: replaced the patchwork of different state and local regulations with a set of uniform national air quality standards that were to protect human health “with a reasonable margin of safety.”

Particulate Matter (PM) refers to a mixture of small solid or liquid particles suspended in air. Some particulates can be seen as dust, smoke, or haze, while the smallest can be identified only with an electron microscope. Technology-related particulate emissions are given off by fuel combustion (such as ash or soot particles from coal and oil burning) and by most industrial and manufacturing processes. The health effects associated with particulate air pollution include respiratory and cardiovascular disease, damage to lung tissue, and (potentially) carcinogenesis and premature death. Particles may take on additional potency by serving as carriers that absorb other pollutants on particle surfaces. The size of particulate matter strongly affects the scope and severity of its impacts. Particles smaller than 10 microns (or 10 micrometers) - referred to as PM10 - are fine enough to penetrate deeply into the lungs, releasing pollutants on moist lung surfaces. In addition to health effects, particulate matter can reduce visibility, cause soiling or damage to materials, and pose a nuisance in the form of dust. Sulfur Dioxide (SO2) is emitted primarily from the combustion of coal and oil, which contain sulfur as an impurity. Exposure to high concentrations of SO2 can lead to respiratory illnesses, alterations in the lung’s defenses, and aggravation of existing cardiovascular or chronic lung disease. SO2 emissions from power plants and other sources also can undergo chemical reactions in the atmosphere to form gaseous sulfates and sulfate particles that eventually fall as acidic precipitation. Carbon Monoxide (CO) is a colorless, odorless gas that is produced when fossil fuels or other carbon-containing materials are not completely combusted. When inhaled, carbon monoxide is absorbed by blood hemoglobin, which normally carries oxygen to the body. Exposure to elevated levels of CO in the atmosphere can produce a spectrum of adverse health effects such as shortness of breath and dizziness as the body’s oxygen delivery system is choked off. Nitrogen Dioxide (NO2) is a reddish-brown gas that is toxic in very high concentrations. At the lower concentrations typical of polluted urban air, NO2 can irritate the respiratory system and produce respiratory illnesses such as bronchitis. NO2 is primarily a result of fuel combustion. NO2 is in the family of compounds called nitrogen oxides, which contain nitric oxide (NO). At high temperatures found in modern combustion processes, NO is formed from the nitrogen and oxygen found in air and fuel. When the NO is released to the atmosphere, it gradually oxidized to NO2. Although only NO2 is a criteria air pollutant, emission control requirements usually are specified on the basis of total nitrogen oxides, reported as equivalent NO2. The air pollutant ozone found at ground level be thought of as “bad” ozone, in contrast to the protective layer of “good” ozone found in the stratosphere high above the earth. Ground-level ozone causes health problems because it attacks lung tissue, reduces lung function, and sensitizes the lungs to other irritants. Strategies to reduce atmospheric ozone concentrations require reductions in NOx and hydrocarbon emissions.

Lead is a heavy metal that can cause neurological damage and adverse effects on organs such as the liver and kidneys. Once ingested via inhalation or other means, lead tends to bioaccumulate in blood, bone, and soft tissues, so that its effects are not easily reversible. The major sources of atmospheric lead in the United States now are lead smelting and manufacturing processes. 2.3.2 Air Toxics Air toxics are emitted in much smaller quantities that criteria air pollutants, but their effects can be severe, even in small doses. Carcinogenic substances like asbestos and benzene are of particular concern, as are heavy metals and other chemicals that may cause neurological, immunological, mutagenic, and other serious health effects. 2.3.3 Acid Deposition Acid deposition, commonly known as acid rain, refers to the fallout of acidic particles or any type of precipitation, such as rain, fog, mist, or snow, that is more acidic than normal. 2.3.4 Stratospheric Ozone Depletion A thin layer of ozone molecules in the stratosphere 10-40 km above the earth's surface absorbs high-energy solar radiation incident upon the planet. This is sufficient to prevent most of the intense radiation known as ultraviolet-B from reaching the earth’s surface, shere it would cause damaging effects by destroying protein and DNA molecules in biological tissue. 2.3.5 Greenhouse Gases Greenhouse gases trap heat in the atmosphere in much the same way that glass helps to trap solar energy in a greenhouse. Solar energy is radiated from the sun at short wavelengths and is partially absorbed by the earth’s surface. The warned surface in turn radiates energy back to space, but at much longer wavelengths. 2.4 Water Pollution 2.4.1 Sources and Uses of Water Surface waters, which include all the lakes, streams, and rivers that flow into the oceans is the most plentiful sources of water for human activities. These waters are depleted by evaporation and replenished by precipitation as part of the natural hydrological cycle, Groundwater refers to underground water sources. Groundwater water is released naturally through springs, or it can be pumped to the surface via human intervention.

Chief among human needs for water are municipal water supplies, which provide water for drinking, cooking, and other domestic activities. 2.4.2 Major Water Contaminants Pathogens are disease-causing agents such as bacteria, viruses, protozoa, and parasitic worms called helminths. These microorganisms are commonly found in the intestines of infected people or animals, and they are excreted in the feces that enter sewer systems or fall onto the ground. If ingested, the can cause human illnesses ranging from life-threatening diseases such as typhoid, cholera, diarrhea, and dysentery to minor gastrointestinal, respiratory and skin diseases. Organic Wastes are the main source of oxygen-depleting substances in surface waters. Nutrients used in fertilizers tend to bind and cling to clay and humus particles in soils and are therefore easily transported to surface water supplies through erosion and runoff.

Chapter 12: Global warming and greenhouse effect 12.1 Introduction Greenhouse structures traps some sunlight inside which cause the structure to heat up. The same applies to the earth. 12.1.1 Greenhouse Gas Emissions and Atmospheric Change 12.1.2 The Global Climate System 12.1.3 Chapter Overview 12.2 Fundamentals of the Greenhouse effect 12.2.1 The Nature of Radiative Energy 12.2.2 Solar Energy Reaching Earth 12.2.3 A simple Earth Energy Balance 12.2.4 Temperature and the Radiative Spectrum 12.2.5 The Earth’s Atmosphere 12.2.6 Radiative Properties of the Atmosphere 12.2.7 The Greenhouse Effect Defined 12.2.8 Earth Energy Balance Revisited 12.2.9 Actual Radiative Balance 12.3 Radiative forcing of climate change 12.3.1 Modes of Radiative Forcing 12.3.2 Net Forcing from Atmospheric Changes 12.3.3 Quantifying Radiative Forcing 12.3.4 Radiative Forcing versus Concentration 12.3.5 Radiative Forcing in the Industrial Age 12.3.6 Equivalent CO2 Concentration

12.4 Temperature changes from radiative forcing 12.4.1 Restoring the Earth’s Energy Balance 12.4.2 Evaluating the Climate Sensitivity Factor 12.4.3 Results from Observational Data 12.4.4 Results from Climate Models 12.4.5 Time Lags and Temperature Commitment 12.5 Climate change predictions 12.5.1 Temperature Change since Preindustrial Times 12.5.2 Global Warming in the 21st Century 12.6 Historical Temperature Changes 12.7 Stabilizing atmospheric concentrations 12.7.1 Atmospheric Lifetime of Greenhouse Gases 12.7.2 The Carbon Cycle 12.7.3 Stabilization Scenarios 12.8 CO2 Emissions and Energy use 12.8.1 Carbon Content of Fuels 12.8.2 Energy Contents of Fuels 12.8.3 Carbon Intensity of Fuels 12.8.4 Regional Sources of CO2 Emissions 12.9 Reducing greenhouse gas emissions 12.9.1 Factors Affecting CO2 Emissions Growth 12.9.2 Reducing Energy Intensity 12.9.3 Reducing Carbon Intensity 12.9.4 Reducing Non-CO2 Emissions 12.9.5 Evaluating Emission Reduction Strategies 12.10 Future outlook 12.10.1 The Kyoto Protocol 12.10.2 Beyond Kyoto 12.11 Conclusion

Chapter 7: Life Cycle Assessment 7.1 Introduction 7.2 Principles of Life Cycle Assessment Life Cycle assessment is to provide a framework so that decisions made today will be viewed many years from now as the “right” decisions on environmental impacts. LCA provide the framework taking environmental effects into decision-making process. 7.2.1 Making Decisions about Product Design

7.2.2 Steps in a ...