Emission control devices

Process vents and drains, including emission control devices, are often overlooked but are important elements in the safety of batch systems. Inadequate attention to these items can result in incompatible chemical mixtures within the... 

Catalytic afterburners are currently used primarily in industry for the control of solvents and organic vapor emissions from industrial ovens. They are used as emission control devices for gasoline-powered automobiles (see Chapter 31). 

The buyers of motor vehicles have been substantially positive concerning the need to have cleaner running vehicles. Although the required emission control devices and other mandated safety equipment have increased the cost of new motor vehicles, sales have not been significantly effected. The current environmental awareness and concern are evidence of the general population s new found knowledge and acceptance of both mobile and stationary source emission controls. 

Describe typical sources and types of air emissions resulting from steelmaking. What are some pollution prevention practices used in this industry What are some of the emission control devices used and for what purposes ... 

Residuals Produced Liquid injection incinerators produce ash which may require application of a post treatment technology prior to disposal. The byproducts from the emission control devices may also require further treatment prior to disposal. 

Provide vapor removal system to a scrubber or other emission control device. 

A recent trend is the development of park and ride areas for transit passengers to drive to transit. These facilities help make transit accessible to a wide geographic area. Because emissions control devices are ineffective when cold, the auto trip to the transit station may produce nearly as many pollutants as a direct trip to the final destination. Further, park and ride lots occupy a lot of space, making transit stations... 

One of the most significant Indices of air pollution potential Is provided by statistics on motor vehicle use. On a global scale the number of vehicles continues to rise although the rate of growth has slowed In North America and Europe as a whole, where vehicle densities are the highest In the world. Since 1979, the most rapid growth has occurred In Asia and South America where vehicle ownership has more than doubled (11). In the developing countries, as well as many others, these vehicles are not equipped with emission control devices. 

Pollutants and sludges extracted from CAA air emission control devices are subject to RCRA hazardous waste regulations if hazardous... 

Title V requires that all major sources (and certain minor sources) obtain an operating permit. Many pulp and paper mills are required to have a Title V permit, and may be required to submit information about emissions control devices and the general process at the facility in the permit application. Permits may limit pollutant emissions and impose monitoring record keeping and reporting requirements. 

In previous studies we found that improved emission-control devices (such as hot-side electrostatic precipitaters and wet-scrubber systems) now being installed on modern pulverized-coal-fired power plants modify the quantity, chemical composition, and distribution characteristics of fine aerosol emissions (12,13). Such modifications must be understood to adequately assess human health and environmental hazards, and to apportion the contributions of sources to urban pollutant inventories. 

Based on the above description of the coal combustion process several conclusions become apparent. First, the type and amount of ash accumulated during coal combustion greatly depends on the mineralogy of the coal being used, the combustion process, and the presence of emission control devices. Secondly, the chemical forms in which elements are found in ash are affected by coal combustion process variables such as combustion temperature and the mode of combustion (e.g., pulverized-coal fired, fluidized bed, cyclone, stoker). Lastly, the amount of CCPs accumulated by power plants is predominantly a consequence of the presence of emission control devices. The latter is supported by the fact that the total amount of CCPs produced in the US has increased significantly since the use of electrostatic precipitators became prevalent in the early 1970s (Simsiman et al. 1987). 

N02 diffusion from the catalyst in/on the filter wall back to the soot layer (so-called back diffusion ). 1-3 and 5 have been covered extensively (Bissett, 1984 Haralampous et al., 2004 Huynh et al., 2003 Konstandopoulos and Johnson, 1989 York et al., 2005, 2007), and are also covered in part elsewhere in this volume (Konstandopoulos et al., this volume). The application of a coated filter as a gaseous emissions control device has received far less attention and will be discussed now. 

As we proceed to the entire exhaust system scale we face the task of interfacing the DPF behavior to that of other emission control devices in the exhaust (e.g. diesel oxidation catalysts (DOC) and NOx reduction devices). An example of a coupled simulation of a DOC and a DPF in series is shown in Fig. 43. We observe how a hydrocarbon pulse injection upstream of the DOC raises the exhaust temperature and causes regeneration of the DPF. Such simulation tools are very useful for the development and optimization of postinjection strategies for DPF regeneration. 

While evaporators have tremendous potential for use in plating and surface finishing operations there is a concern over the environmental impact of air emissions from them (Foecke 1989). Emission control devices might be required for them in the future. 

Depending on the environmental conservation requirements, a deNOjng, deSOjng, and particulate emission control device can be included in the flue gas train. 

To meet emissions limits, the Modesto Project had to install state-of-the-art emission control devices. Detailed descriptions of all air pollution control equipment is contained in Section 3.3. 

Oxford experienced difficulties at first with several of their emission control devices. These difficulties have been overcome. Based on Oxford Energy s experiences, controlled emissions from their Modesto Energy Project compare extremely favorably to controlled emissions from electric utility plants powered by traditional fuels. Most emission rates (lbs/MMBtu) at Oxford are below those at other electric generating plants burning traditional fuels. 

The primary area of interest of this investigation was the effect of burning tires or TDF on the emissions from the process. Other areas of concerns were the emission control devices, changes to controls necessary to facilitate burning tires or TDF, and the economics of burning tires or TDF. 

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