Category: Industrial Pollution Sources Its Characterization, Estimation and Treatment
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Nuclear Waste Management
Of particular concern in nuclear waste management are two long‐lived fission products, Tc‐99 (half‐life 220 000 years) and I‐129 (half‐life 15.7 million years), which dominate spent fuel radioactivity after a few thousand years. The most troublesome transuranic elements in spent fuel are Np‐237 (half‐life two million years) and Pu‐239 (half‐life 24 000 years) (Nuclear Decommissioning Authority 2014). Nuclear waste requires sophisticated treatment…
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Coal
Coal contains a small amount of radioactive uranium, barium, thorium, and potassium but, in the case of pure coal, this is significantly less than the average concentration of those elements in the Earth’s crust. The surrounding strata, if shale or mudstone, often contain slightly more than average and this may also be reflected in the…
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Incineration, Destruction, and WtE
Hazardous waste may be “destroyed.” For example, by incinerating it at a high temperature, flammable wastes can sometimes be burned as energy sources. For example, many cement kilns burn hazardous wastes like used oils or solvents. Today, incineration treatments not only reduce the amount of hazardous waste but also generate energy from the gases released in…
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Hazardous Waste
Hazardous waste is waste that poses substantial or potential threats to public health or the environment (see Table C2 (“a”, “b”, “c”, “d”)). In the United States, the treatment, storage, and disposal of hazardous waste are regulated under the RCRA. Hazardous wastes are defined under RCRA in the Title 40 CFR 261 where they are…
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Wastes in the United States
As a nation, Americans officially generate more waste than any other nation in the world, with more than 12 billion T of industrial waste are generated annually in the United States. And the United States’s “waste stream” comes from manufacturing, retailing, and commercial trade in the US economy. This is equivalent to more than 40 T of waste…
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Material Balances and Energy Balances
Material balances, also called mass balances and energy balances, are applications of conservation of mass and energy to the analysis of physical systems. Process and equipment selections and sizing require a complete knowledge of all material and energy flow to and from each unit. By accounting for material and/or energy entering and leaving a system,…
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Gas Flowrate Conversion from SCFM to ACFM
EXAMPLE 3.12 For a boiler, 200 lb‐mol/h of air at STP will be required for complete combustion of methane. What is the actual flow rate per minute at stack condition at 800 °F at 1 atm. SOLUTION Corrections for Percent O2 Corrections for percent O2 are often needed for referencing combustion source emissions. For boilers, comparisons are made at…
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Flow at Standard Temperature and Pressure
Flow at standard temperature and pressure (STP) can be determined provided actual temperature and pressure of the flow are known. Using EPA’s standard conditions 20 °C (68 °F), flow at STP becomes: (3.17) where Pm is the measured pressure in psi and Tm is the measured temperature in °R (°R = 460 + °F).
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Gas Flow Measurement
A fixed number of moles of gas at a certain temperature and pressure occupies a certain volume. If the pressure and temperature of this fixed number of moles of gas are changed, then the new volume can be easily calculated. Equation (3.5) can be written as follows: (3.14) Since n is constant in this case, applying Eq. (3.14) to the two…
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Other Applications of the Ideal Gas Law
As mentioned in Section 3.10, the ideal gas law is extremely important to air pollution engineers. Compliance with federal and state laws requires not only proper environmental engineering design and operation of pollution abatement equipment but also careful analysis and accurate measurements of specified pollutants and environmental quality parameters. In the design process and in other…