Utilities, pollution source

Another type of utility that is a serious air pollution source is the one that handles the wastes of modem society. An overloaded, poorly designed... 

The most widespread and persistent urban pollution problem is ozone. The causes of this and the lesser problem of CO and PMjq pollution in our urban areas are largely due to the diversity and number of urban air pollution sources. One component of urban smog, hydrocarbons, comes from automobile emissions, petroleum refineries, chemical plants, dry cleaners, gasoline stations, house painting, and printing shops. Another key component, nitrogen oxides, comes from the combustion of fuel for transportation, utilities, and industries. 

Ocean prevents eutrophication. Much more water flows into the Mediterranean Sea than is required to replace evaporation from it. The excess, high salinity water exits Gibraltar below the water flowing in af fhe surface. Nufrients that enter the Mediterranean Sea from pollution sources are utilized by marine phytoplankton that sinks and exits with the outflow. Another example is that estuaries often have lower salinity or even freshwater at the surface with a denser saline layer at the bottom. An estuarine circulation occurs with nutrients being trapped in the saline bottom water. 

The minimisation of gas emissions as CO2, SO2, NO, and other acid gases is a key topic in sustainable process design. This problem can be handled only by a systematic approach of all the pollution sources generated by energy integration, namely the utility system, heat recovery and cogeneration, as well as by process modifications. 

Even though society has moved toward centralized industries and utilities, we still have many personal sources of air pollution for which we alone can answer—(1) automobiles, (2) home furnaces, (3) home fireplaces and stoves, (4) backyard barbecue grills, and (5) open burning of refuse and leaves. Figure 6-4 illustrates the personal emissions of a typical U.S. family. 

The energy release and air pollution emissions from personal sources in the United States are greater than those from industry and utilities combined. In any major city in the United States, the mass of pollutants emitted... 

Under low-dose conditions, forest ecosystems act as sinks for atmospheric pollutants and in some instances as sources. As indicated in Chapter 7, the atmosphere, lithosphere, and oceans are involved in cycling carbon, nitrogen, oxygen, sulfur, and other elements through each subsystem with different time scales. Under low-dose conditions, forest and other biomass systems have been utilizing chemical compounds present in the atmosphere and releasing others to the atmosphere for thousands of years. Industrialization has increased the concentrations of NO2, SO2, and CO2 in the "clean background" atmosphere, and certain types of interactions with forest systems can be defined. 

Gaussian techniques, discussed in Chapter 19, are reasonable for estimates of concentrations of nonreative pollutants within 20 km of point sources. It is preferable to utilize on-site wind fluctuation measurements to estimate the horizontal and vertical spreading of a pollutant plume released from a point source. 

For structures and equipment, the utility should be located where it cannot be affected by natural and climatic conditions. This includes (1) corrosive pollution that may be airborne, (2) prevalent winds, and (3) surface water currents from near or remote sources. 

Recycle refers to the utilization of a pollutant-laden stream (a source) in a process unit (a sink). Each sink has a number of constraints on the characteristics (e g, flowrate and composition) of feed that it can process. If a source satisfies these constraints it may be directly recycled to or reused in the sink. However, if the source violates these constraints segregation, mixing, and/or interception may be used to prepare the stream for recycle. 

As mentioned in Chapter One, recycle refers to the utilization of a pollutant-laden stream (a source) in a process unit (a sink). A source may be recycled to a sink... 

One feature of the new law is an SO, trading allowance program that encourages the use of market-based principles to reduce pollution. Utilities may trade allowances within their system and/or buy or sell allowances to and from other affected sources. For example, plants that emit SO, at a rate below 1.2 Ib/million Btu will be able to increase emissions by 20 percent between a baseline year and the year 2000. Also, bonus allowances will be distributed to accommodate growth by units in states with a statewide average below 0.8 Ib/million Btu. 

Biochemical tests are usually performed after pure cultures have been obtained. The standard indole, methyl red, Voges-Proskauer, citrate, and litmus milk tests may be used to show important physiological characteristics. To study the functional diversity of bacteria, the utilization of carbohydrates, amines, amides, carboxylic acids, amino acids, polymers, and other carbon and nitrogen sources can be tested.28 Dilution-based most-probable number (MPN) techniques with phospholipid fatty acids as biomarkers have been employed for studying different bacterial species in lakes.40 The patterns of antibiotic resistance in bacteria isolated from natural waters have been useful for identifying sources of water pollution.34... 

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