Fixing Coal Pollution: Cleaning Our Air And Environment

Coal is a major source of air pollution, which has been linked to asthma, cancer, heart and lung ailments, neurological problems, acid rain, and global warming. In 2022, coal-fired power plants in the US emitted 197,286 tons of small airborne particles, as well as lead, cadmium, arsenic, carbon monoxide, and other toxic heavy metals. Coal mining and extraction techniques have also led to the release of pollutants, changed landscapes, and contaminated water sources. To combat these issues, the US has implemented laws and regulations, such as the Clean Air Act and the Clean Water Act, and developed technologies to reduce emissions and capture pollutants. However, the true costs of coal are often not fully recognized, and our continued reliance on coal for electricity has driven the climate system to a critical state.

Reduce coal consumption

Reducing coal consumption is key to mitigating the harmful effects of coal on the environment and human health. Coal consumption has historically been linked to middle-income countries, with a strong relationship between development level and coal consumption. However, as incomes rise, a shift towards less polluting fuels, such as oil, natural gas, and renewable energy, becomes more feasible.

One effective strategy to reduce coal consumption is to implement stricter environmental policies and carbon taxes. For instance, the United Kingdom's carbon pricing scheme successfully reduced its coal dependence by 12.4 percentage points from 2013 to 2018. Similarly, government subsidies in Spain, favoring renewable electricity generation, contributed to a decline in coal usage between 2005 and 2010. These examples demonstrate how policy interventions can incentivize the adoption of cleaner energy sources and reduce coal consumption.

Another approach is to improve the efficiency of coal-fired power plants and industrial processes that rely on coal. The coal industry has made advancements in cleaning coal post-mining, and some consumers have transitioned to low-sulfur coal. Additionally, power plants have employed flue gas desulfurization equipment (scrubbers) to reduce sulfur emissions and remove particulates and heavy metals from smoke. These technologies not only reduce the amount of harmful pollutants released into the atmosphere but also enhance the energy efficiency of coal, reducing the amount needed to produce the same amount of energy.

Furthermore, reusing and recycling waste produced from burning coal can help mitigate the environmental impact of coal consumption. Waste products captured by scrubbers can be utilized to produce materials such as cement and synthetic gypsum for wallboard. Additionally, land previously used for coal mining can be reclaimed and repurposed for airports, landfills, or recreational spaces like golf courses.

While reducing coal consumption is a gradual process, taking several decades in some cases, it is crucial to address the environmental and health consequences associated with coal. By implementing a combination of policy measures, technological advancements, and waste reduction strategies, we can collectively work towards lowering coal consumption and mitigating its harmful impacts.

Implement CMM abatement technologies

Coal mine methane (CMM) is a significant source of methane emissions, and abating these emissions is crucial for reducing the coal industry's environmental impact. CMM abatement technologies are already being implemented at various sites worldwide, but they are not yet standard industry practice. This is due to several challenges, such as a lack of potential users of power or natural gas, economic barriers, and legal and regulatory issues surrounding methane ownership.

However, it is estimated that over half of global CMM emissions can be avoided using existing technologies. The implementation of these technologies varies depending on the characteristics of the mine, including methane concentrations, emission volumes, and the scale of operations. For example, underground mines have a higher abatement potential than surface mines due to the more concentrated and contained nature of CMM in these settings.

One effective method to reduce CMM emissions is through degasification systems, such as degasification wells and drainage boreholes, which capture methane from coal deposits. These systems are particularly useful for underground mines but can also be applied to surface mines. The captured CMM can be utilised for generating heat and electricity or sold to industrial customers. If utilisation is not feasible, flaring or other combustion technologies can be employed to mitigate methane's impact as a greenhouse gas.

Another critical abatement measure is targeting methane emissions from ventilation systems, which is estimated to reduce global CMM emissions by almost 30%. This approach requires strong policy action and economic incentives to overcome the marginal potential for energy recovery. Integrating CMM into emissions trading schemes could be a viable strategy for methane mitigation. Additionally, in underground mines, the recovered methane from ventilation systems can be used for coal drying or to generate heat for mine facilities.

To summarise, implementing CMM abatement technologies is a crucial step in mitigating the environmental impact of the coal industry, particularly in reducing methane emissions. While challenges exist, the potential for reducing global CMM emissions using existing technologies is significant, and the captured methane can even be utilised for energy generation. By addressing these challenges and prioritising abatement measures, the coal industry can play a more sustainable role in meeting energy demands while minimising its ecological footprint.

Improve coal cleaning processes

Improving coal cleaning processes can play a crucial role in reducing air pollution stemming from coal. Coal cleaning, or coal beneficiation, involves the removal of minerals and other impurities from coal prior to its combustion. This process can be achieved through physical and chemical means, enhancing the quality of coal and mitigating its environmental impact.

Physical coal cleaning typically employs gravimetric processes, often in conjunction with froth flotation. By leveraging the density differences between coal and its impurities, these techniques effectively separate and eliminate unwanted components, such as minerals and non-combustible materials. Froth flotation, for instance, utilizes the difference in surface properties between coal and impurities, allowing coal particles to attach to air bubbles and float to the surface, leaving the impurities behind.

Chemical coal cleaning, on the other hand, involves the use of chemical reagents to separate coal from its associated minerals and impurities. This process can include chemical reactions, flotation, or a combination of both. The specific chemical reagents and processes employed depend on the characteristics of the coal and the impurities present.

To further enhance the effectiveness of coal cleaning, advanced technologies such as coal washing and carbon capture and storage (CCS) can be utilized. Coal washing involves removing soil and rock impurities from coal before it enters the factory, reducing the presence of non-coal bearing materials. CCS, meanwhile, captures carbon emissions from burning coal and stores them in underground pockets of porous rock. While CCS is effective in capturing carbon dioxide, it does not address other harmful pollutants emitted during coal combustion, such as mercury and nitrogen oxide.

In addition to these techniques, the utilization of integrated gasification combined cycle (IGCC) technology in coal-fired power plants can significantly reduce pollution. IGCC employs a combustion turbine to generate electricity and routes excess heat to a traditional steam turbine for additional power generation. This dual-cycle process increases efficiency and reduces the environmental footprint of coal combustion.

By implementing these improved coal cleaning processes and technologies, we can substantially mitigate the air pollution associated with coal. These measures not only enhance the quality of coal but also help reduce the release of harmful pollutants, protecting both human health and the environment.

Reuse and recycle waste from coal burning

Reusing and recycling waste produced from burning coal can help to reduce the environmental effects of coal production and consumption. Land that was previously used for coal mining can be reclaimed and repurposed for airports, landfills, and golf courses.

One of the largest types of industrial waste generated in the United States is coal ash, which includes by-products such as fly ash, bottom ash, boiler slag, and flue gas desulfurization material. In 2014, nearly 130 million tons of coal ash were generated, and coal combustion waste (CCW) continues to accumulate at a rate of about 131 million tons per year in the United States alone.

CCW can be recycled and put to "beneficial use," according to state definitions. For example, about 6.7 million tons of CCW are used to fill abandoned mines to neutralize acidic liquids that can drain into nearby waters. Additionally, 10.6 million tons are used for structural fills and embankments. However, critics argue that these applications are closer to unregulated dumping than recycling, as they are exempt from safeguards required for disposed waste, such as using liners to prevent leaching of toxic metals into ground and surface waters.

Recycling CCW can provide environmental, economic, and product benefits. It can reduce greenhouse gas emissions, decrease the need for landfill disposal, and reduce the use of other materials. Economic benefits include reduced coal ash disposal costs, increased revenue from coal ash sales, and savings from using coal ash instead of more expensive materials. Product benefits include improved strength, durability, and workability of materials. For instance, concrete containing more than 50% fly ash resists the cracking and corrosion associated with seawater.

Waste products captured by scrubbers (flue gas desulfurization equipment) can be used to produce cement and synthetic gypsum for wallboard. Additionally, some mines capture, use, or sell coalbed methane, which is released during mining operations and must be vented out of mines for safety reasons.

Switch to clean energy sources

Switching to clean energy sources is crucial to address coal and air pollution problems. Fossil fuels like coal are the largest contributors to global climate change, accounting for over 75% of greenhouse gas emissions and 90% of carbon dioxide emissions. The burning of coal releases harmful pollutants, including particulate matter, heavy metals, and toxic gases, causing respiratory illnesses, heart ailments, and neurological problems.

Clean energy sources, such as wind, solar, and geothermal power, emit little to no greenhouse gases or pollutants. Wind energy, generated through wind turbines, is one of the cleanest sources as it doesn't directly affect air pollution emissions and doesn't require water for cooling. Solar power is another clean and safe alternative, although its costs are expected to remain high in the near term due to elevated commodity and freight prices.

The benefits of investing in these clean energy sources are significant when considering both air quality and climate change mitigation. By 2030, renewable energy sources could provide 65% of the world's electricity supply, massively reducing carbon emissions and improving air quality. This transition to clean energy is expected to create over 30 million jobs by 2030 and will require substantial investment, estimated at $4.5 trillion annually until 2030, to achieve net-zero emissions by 2050.

To facilitate the switch to clean energy sources, governments and industries must address economic, legal, and regulatory challenges. Additionally, ensuring a just transition that prioritizes the needs and rights of people is essential to guarantee that no one is left behind during this critical shift towards a sustainable future.

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