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45-442: There is currently research being done in firing fossil fuel power plants with an oxygen-enriched gas mix instead of air. Almost all of the nitrogen is removed from input air, yielding a stream that is approximately 95% oxygen. Firing with pure oxygen would result in too high a flame temperature, so the mixture is diluted by mixing with recycled flue gas , or staged combustion . The recycled flue gas can also be used to carry fuel into

90-417: A fireplace , oven , furnace , boiler or steam generator . Quite often, the flue gas refers to the combustion exhaust gas produced at power plants . Its composition depends on what is being burned, but it will usually consist of mostly nitrogen (typically more than two-thirds) derived from the combustion of air, carbon dioxide (CO 2 ), and water vapor as well as excess oxygen (also derived from

135-416: A checkerboard pattern to capture heat as flue gas exits the furnace. When the flue duct is thoroughly heated, air flow is reversed and the flue duct becomes the air inlet, releasing its heat into the incoming air, and allowing for higher furnace temperatures than can be attained with air-fuel only. Two sets of regenerative flue ducts allowed for the air flow to be reversed at regular intervals, and thus maintain

180-587: A high concentration of CO 2 , it makes it easier to purify and store the CO 2 rather than releasing it to the atmosphere. Many fossil fuels, such as coal and oil shale , produce ash as a result of combustion. This ash also needs to be disposed of, which may impact the environment. So far studies indicate that, in general, oxyfuel combustion does not significantly affect the composition of ash produced. Measurements have shown similar mineral and heavy metal concentrations regardless of whether an air or oxyfuel environment

225-479: A high temperature in the incoming air. By allowing new furnaces to be built without the expense of regenerators, and especially with the added benefit of nitrogen oxide reduction, which allows glass plants to meet emission restrictions, oxy-fuel is cost effective without the need to reduce CO 2 emissions. Oxy-fuel combustion also reduces CO 2 release at the glass plant location, although this may be offset by CO 2 production due to electric power generation which

270-710: A means of greenhouse gas remediation , and have begun to be implemented in a limited way commercially (e.g. the Sleipner West field in the North Sea , operating since 1996). There are a number of proven technologies for removing pollutants emitted from power plants that are now available. There is also much ongoing research into technologies that will remove even more air pollutants. Most fossil fuels are combusted with ambient air (as differentiated from combustion with pure oxygen ). Since ambient air contains about 79 volume percent gaseous nitrogen (N 2 ), which

315-499: A regional, national or international level by government organizations. The largest international agency, set up in 1972, is the United Nations Environment Programme . The International Union for Conservation of Nature brings together 83 states, 108 government agencies, 766 Non-governmental organizations and 81 international organizations and about 10,000 experts, scientists from countries around

360-406: A traditional air-fired plant. The main problem has been separating oxygen from the air. This process requires much energy, nearly 15% of production by a coal-fired power station can be consumed for this process. However, a new technology which is not yet practical called chemical looping combustion can be used to reduce this cost. In chemical looping combustion, the oxygen required to burn the coal

405-407: Is a tool of environmental management forming a part of project approval and decision-making. Environmental assessments may be governed by rules of administrative procedure regarding public participation and documentation of decision making, and may be subject to judicial review. The environmental movement (sometimes referred to as the ecology movement) is a social movement that aims to protect

450-448: Is available to remove pollutants from flue gas at power plants. Combustion of fossil fuels is a common source of flue gas. They are usually combusted with ambient air, with the largest part of the flue gas from most fossil-fuel combustion being nitrogen , carbon dioxide , and water vapor . Flue gas is the gas exiting to the atmosphere via a flue , which is a pipe or channel for conveying exhaust gases from combustion , as from

495-526: Is common in various aspects of metal production. The glass industry has been converting to oxy-fuel since the early 1990s because glass furnaces require a temperature of approximately 1500 degrees C, which is not economically attainable at adiabatic flame temperatures for air-fuel combustion unless heat is regenerated between the flue stream and the incoming air stream. Developed in the mid-19th century, glass furnace regenerators are large and expensive high temperature brick ducts filled with brick arranged in

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540-457: Is currently available. This financial disparity raises questions about the global commitment to equitable climate action and underscores the need for a substantial increase in support and resources. The IPCC's analysis suggests that with adequate financial investment and international cooperation, it is possible to embark on a pathway towards resilience and sustainability that benefits all sections of society. Environmental impact assessment (EIA)

585-647: Is defined as any change or disturbance to the environment perceived to be deleterious or undesirable. The environmental degradation process amplifies the impact of environmental issues which leave lasting impacts on the environment. Environmental degradation is one of the ten threats officially cautioned by the High-level Panel on Threats, Challenges and Change of the United Nations . The United Nations International Strategy for Disaster Reduction defines environmental degradation as "the reduction of

630-443: Is essentially non-combustible, the largest part of the flue gas from most fossil-fuel combustion is uncombusted nitrogen. Carbon dioxide (CO 2 ), the next largest part of flue gas, can be as much as 10−25 volume percent or more of the flue gas. This is closely followed in volume by water vapor (H 2 O) created by the combustion of the hydrogen in the fuel with atmospheric oxygen. Much of the 'smoke' seen pouring from flue gas stacks

675-432: Is formed from nitric and nitrous oxide interacting with water - eliminating nitrogen from combustion reduces this factor altogether. Flue gas Flue gas is the gas exiting to the atmosphere via a flue , which is a pipe or channel for conveying exhaust gases , as from a fireplace, oven, furnace , boiler or steam generator . It often refers to the exhaust gas of combustion at power plants . Technology

720-425: Is higher). Environmental impacts Environmental issues are disruptions in the usual function of ecosystems . Further, these issues can be caused by humans ( human impact on the environment ) or they can be natural. These issues are considered serious when the ecosystem cannot recover in the present situation, and catastrophic if the ecosystem is projected to certainly collapse. Environmental protection

765-563: Is inequitably distributed. The movement began in the United States in the 1980s. It was heavily influenced by the American civil rights movement and focused on environmental racism within rich countries. The movement was later expanded to consider gender, international environmental injustice, and inequalities within marginalized groups. As the movement achieved some success in rich countries, environmental burdens were shifted to

810-501: Is necessary to produce oxygen for the combustion process. Oxy-fuel combustion may also be cost effective in the incineration of low BTU value hazardous waste fuels. It is often combined with staged combustion for nitrogen oxide reduction, since pure oxygen can stabilize combustion characteristics of a flame. There are pilot plants undergoing initial proof-of-concept testing to evaluate the technologies for scaling up to commercial plants, including One case study of oxy-fuel combustion

855-614: Is produced internally by oxidation and reduction reactions, as opposed to using more expensive methods of generating oxygen by separating it from air. At present in the absence of any need to reduce CO 2 emissions, oxy-fuel is not competitive. However, oxy-fuel is a viable alternative to removing CO 2 from the flue gas from a conventional air-fired fossil fuel plant. However, an oxygen concentrator might be able to help, as it simply removes nitrogen. In industries other than power generation, oxy-fuel combustion can be competitive due to higher sensible heat availability. Oxy-fuel combustion

900-471: Is reactive and can potentially affect the environment, for instance by increasing the alkalinity of the ash. Because oxyfuel combustion takes place in a CO 2 -rich atmosphere, decomposition is reduced and the ash generally contains less free lime. Flue gas desulfurization is usually employed to increase the pH of flue gases or their product when reacting with atmospheric moisture ( acid rain ). Besides sulfur and its oxides, another potential acid rain component

945-445: Is the assessment of the environmental consequences of a plan, policy, program, or actual projects prior to the decision to move forward with the proposed action. In this context, the term "environmental impact assessment" is usually used when applied to actual projects by individuals or companies and the term " strategic environmental assessment " (SEA) applies to policies, plans and programmes most often proposed by organs of state. It

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990-590: Is the attempted White Rose plant in North Yorkshire, United Kingdom. The planned project was an oxy-fuel power plant coupled with air separation to capture two million tons of carbon dioxide per year. The carbon dioxide would then be delivered by pipeline to be sequestered in a saline aquifer beneath the North Sea. However, in late 2015 and early 2016, following withdrawal of funding by the Drax Group and

1035-471: Is the practice of protecting the natural environment on the individual, organizational or governmental levels, for the benefit of both the environment and humans. Environmentalism is a social and environmental movement that addresses environmental issues through advocacy, legislation education, and activism. Environment destruction caused by humans is a global, ongoing problem. Water pollution also cause problems to marine life. Most scholars think that

1080-449: Is this water vapor, forming a cloud as it contacts cool air. A typical flue gas from the combustion of fossil fuels contains very small amounts of nitrogen oxides ( NO x ), sulfur dioxide (SO 2 ) and particulate matter . The nitrogen oxides are derived from the nitrogen in the ambient air, as well as from any nitrogen-containing compounds in the fossil fuel. The sulfur dioxide is derived from any sulfur -containing compounds in

1125-927: The Global South (as for example through extractivism or the global waste trade ). The movement for environmental justice has thus become more global, with some of its aims now being articulated by the United Nations . The movement overlaps with movements for Indigenous land rights and for the human right to a healthy environment . The goal of the environmental justice movement is to achieve agency for marginalized communities in making environmental decisions that affect their lives. The global environmental justice movement arises from local environmental conflicts in which environmental defenders frequently confront multi-national corporations in resource extraction or other industries. Local outcomes of these conflicts are increasingly influenced by trans-national environmental justice networks. The 2023 IPCC report highlighted

1170-625: The rights of indigenous people , the rights of peasants , or threats to communities whose livelihoods are dependent on the ocean. Outcomes of local conflicts are increasingly influenced by trans-national environmental justice networks that comprise the global environmental justice movement. Environmental justice is a social movement that addresses injustice that occurs when poor or marginalized communities are harmed by hazardous waste , resource extraction , and other land uses from which they do not benefit. The movement has generated hundreds of studies showing that exposure to environmental harm

1215-511: The sulfur dioxide produced by burning fossil fuels, particularly coal. Nitrogen oxides are treated either by modifications to the combustion process to prevent their formation, or by high temperature or catalytic reaction with ammonia or urea . In either case, the aim is to produce nitrogen gas, rather than nitrogen oxides. In the United States, there is a rapid deployment of technologies to remove mercury from flue gas—typically by absorption on sorbents or by capture in inert solids as part of

1260-574: The " triple planetary crises ": climate change, pollution, and biodiversity loss. 1800s: Martineau · Tocqueville  ·  Marx ·  Spencer · Le Bon · Ward · Pareto ·  Tönnies · Veblen ·  Simmel · Durkheim ·  Addams ·  Mead · Weber ·  Du Bois ·  Mannheim · Elias Human impact on the environment (or anthropogenic environmental impact) refers to changes to biophysical environments and to ecosystems , biodiversity , and natural resources caused directly or indirectly by humans . Modifying

1305-580: The U.K. government, construction was halted. The unforeseen loss of the funding from the UK government's CCS Commercialisation Programme, along with decreased subsidies for renewable energy, left the White Rose Plant with insufficient funds to continue development. One of the major environmental impacts of burning fossil fuels is the release of CO 2 , which contributes to climate change . Because oxyfuel combustion results in flue gas that already has

1350-406: The ambient atmosphere. The table below presents the total amounts of flue gas typically generated by the burning of fossil fuels such as natural gas , fuel oil and coal . The data were obtained by stoichiometric calculations. The total amount of wet flue gas generated by coal combustion is only 10 percent higher than the flue gas generated by natural-gas combustion (the ratio for dry flue gas

1395-498: The boiler and ensure adequate convective heat transfer to all boiler areas. Oxy-fuel combustion produces approximately 75% less flue gas than air fueled combustion and produces exhaust consisting primarily of CO 2 and H 2 O (see figure). The justification for using oxy-fuel is to produce a CO 2 rich flue gas ready for sequestration . Oxy-fuel combustion has significant advantages over traditional air-fired plants. Among these are: Economically speaking this method costs more than

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1440-892: The capacity of the environment to meet social and ecological objectives, and needs". Environmental conflicts, socio-environmental conflict or ecological distribution conflicts (EDCs) are social conflicts caused by environmental degradation or by unequal distribution of environmental resources . The Environmental Justice Atlas documented 3,100 environmental conflicts worldwide as of April 2020 and emphasised that many more conflicts remained undocumented. Parties involved in these conflicts include locally affected communities, states, companies and investors, and social or environmental movements; typically environmental defenders are protecting their homelands from resource extraction or hazardous waste disposal. Resource extraction and hazardous waste activities often create resource scarcities (such as by overfishing or deforestation ), pollute

1485-429: The combustion air). It further contains a small percentage of a number of pollutants, such as particulate matter (like soot ), carbon monoxide , nitrogen oxides , and sulfur oxides . At power plants, flue gas is often treated with a series of chemical processes and scrubbers , which remove pollutants. Electrostatic precipitators or fabric filters remove particulate matter and flue-gas desulfurization captures

1530-404: The disproportionate effects of climate change on vulnerable populations. The report's findings make it clear that every increment of global warming exacerbates challenges such as extreme heatwaves, heavy rainfall, and other weather extremes, which in turn amplify risks for human health and ecosystems. With nearly half of the world's population residing in regions highly susceptible to climate change,

1575-578: The environment to fit the needs of society (as in the built environment ) is causing severe effects including global warming , environmental degradation (such as ocean acidification ), mass extinction and biodiversity loss , ecological crisis , and ecological collapse . Some human activities that cause damage (either directly or indirectly) to the environment on a global scale include population growth , neoliberal economic policies and rapid economic growth , overconsumption , overexploitation , pollution , and deforestation . Some of

1620-506: The environment, and degrade the living space for humans and nature, resulting in conflict. A particular case of environmental conflicts are forestry conflicts, or forest conflicts which "are broadly viewed as struggles of varying intensity between interest groups, over values and issues related to forest policy and the use of forest resources". In the last decades, a growing number of these have been identified globally. Frequently environmental conflicts focus on environmental justice issues,

1665-422: The flue-gas desulfurization product. Such scrubbing can lead to meaningful recovery of sulfur for further industrial use. Technologies based on regenerative capture by amines for the removal of CO 2 from flue gas have been deployed to provide high purity CO 2 gas to the food industry, and for enhanced oil recovery . They are now under active research as a method for CO 2 capture for long-term storage as

1710-410: The fuels. The particulate matter is composed of very small particles of solid materials and very small liquid droplets which give flue gases their smoky appearance. The steam generators in large power plants and the process furnaces in large refineries , petrochemical and chemical plants , and incinerators burn considerable amounts of fossil fuels and therefore emit large amounts of flue gas to

1755-477: The natural world from harmful environmental practices in order to create sustainable living . Environmentalists advocate the just and sustainable management of resources and stewardship of the environment through changes in public policy and individual behavior. In its recognition of humanity as a participant in (not an enemy of) ecosystems , the movement is centered on ecology , health , as well as human rights . Environmental issues are addressed at

1800-416: The problems, including global warming and biodiversity loss, have been proposed as representing catastrophic risks to the survival of the human species. Environmental degradation is the deterioration of the environment through depletion of resources such as quality of air , water and soil ; the destruction of ecosystems ; habitat destruction ; the extinction of wildlife ; and pollution . It

1845-512: The project peak global world population of between 9-10 billion people, could live sustainably within the earth's ecosystems if human society worked to live sustainably within planetary boundaries . The bulk of environmental impacts are caused by excessive consumption of industrial goods by the world's wealthiest populations. The UN Environmental Program, in its "Making Peace With Nature" Report in 2021, found addressing key planetary crises, like pollution, climate change and biodiversity loss,

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1890-548: The urgency for global actions that are both rapid and sustained is underscored. The importance of integrating diverse knowledge systems, including scientific, Indigenous, and local knowledge, into climate action is highlighted as a means to foster inclusive solutions that address the complexities of climate impacts across different communities. In addition, the report points out the critical gap in adaptation finance, noting that developing countries require significantly more resources to effectively adapt to climate challenges than what

1935-531: The world. International non-governmental organizations include Greenpeace , Friends of the Earth and World Wide Fund for Nature . Governments enact environmental policy and enforce environmental law and this is done to differing degrees around the world. There are an increasing number of films being produced on environmental issues, especially on climate change and global warming . Al Gore's 2006 film An Inconvenient Truth gained commercial success and

1980-608: Was achievable if parties work to address the Sustainable Development Goals . Major current environmental issues may include climate change , pollution , environmental degradation , and resource depletion . The conservation movement lobbies for protection of endangered species and protection of any ecologically valuable natural areas, genetically modified foods and global warming . The UN system has adopted international frameworks for environmental issues in three key issues, which has been encoded as

2025-477: Was used. However, one notable exception is that oxyfuel ashes often have lower concentrations of calcium oxide or calcium hydroxide (free lime). Free lime forms when carbonate minerals in fuels like coal and oil shale decompose at the high temperatures occurring during combustion ( calcination ). Calcination is an equilibrium reaction and a higher partial pressure of CO 2 shifts the equilibrium in favor of CaCO 3 and MgCO 3 respectively. Free lime

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